Research ArticleMorphometric Analysis of Lateral Masses of Axis Vertebrae inNorth Indians

Monika Lalit1 Sanjay Piplani2 J S Kullar3 and Anupama Mahajan1

1 Department of Anatomy Sri Guru Ram Das Institute of Medical Science and Research Vallah Amritasr 143001 Punjab India2Department of Pathology Sri Guru Ram Das Institute of Medical Science and Research Vallah Amritasr 143001 Punjab India3 Department of Anatomy Government Medical College Amritsar Punjab India

Correspondence should be addressed to Monika Lalit monikalalityahoocom

Received 28 May 2014 Accepted 30 July 2014 Published 24 August 2014

Academic Editor Udo Schumacher

Copyright copy 2014 Monika Lalit et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Background and ObjectiveThe lateral masses of axis have good cancellous bone quality beneath the articular surface of facets thatmake this area a good site for the insertion of an internal fixation deviceMethods 60 dry axis vertebrae were obtained for anatomicevaluation focused on pedicle superior and inferior articular facets and foramen transversarium Based upon linear and angularparameters the mean range and standard deviation were calculated Results The mean length width and height of the pediclewere 2161 plusmn 237mm 882 plusmn 243mm and 563 plusmn 206mmThe mean pedicle superior angle and median angle were 233 and 322degrees The mean superior articular facet length width and external and internal height were 1634 plusmn 156mm 1435 plusmn 175mm898 plusmn 136mm and 423 plusmn 081mm Depth of vertebral artery was 472 plusmn 083mm Mean inferior articular facet length and widthwere 1113 plusmn 143mm and 789 plusmn 130mm The mean foramen transversarium length and width were 511 plusmn 091mm and 506 plusmn123mm ConclusionsThe study may provide information for the surgeons to determine the safe site of entry and trajectory for thescrew implantation and also to avoid injuries to vital structures while operating around axis

1 Introduction

Axis the second cervical vertebra forms a pivot on whichthe atlas rotates carrying the head to allow greater range ofmotion at the atlantoaxial joints [1 2] The lateral masses ofaxis have good cancellous bone quality beneath the articularsurface of facets that makes this area a good site for insertionof an internal fixation device [3]

The elements of pedicle and pedicle axis are critical to thestructural anatomy of axis vertebra which are important tonormal function and also for cases of pathology or fractureswhen surgical intervention is required [4 5] The superiorarticular facets (SAF) of axis differ from other vertebralfacets which make this region more prone to vertebral arteryinjury during screw fixation [6] In axis vertebrae the SAFlies in proximity to the body and medial aspect of the axisof the pedicle whereas SAF of other vertebrae are lying inproximity to the junction of pedicle and lamina and also thevertebral artery foramen is lying partially or completely in theundersurface of axis while in other vertebrae the vertebral

artery foramen is located entirely in relation to foramentransversarium [7 8] This unusual location of vertebralartery foramen makes the vertebral artery more prone toinjury during screw fixation [9]

The present study may also assist with placement ofscrews into pedicle or lateral mass For this reason theposterior point of projection of the pedicle axis has beendefined in terms of reference points visible in a postsurgicalapproach to the cervical spine and the two angles representthe safe bounds for transpedicular screw fixationplacement[4 10] Thus if there is any variation in the lateral mass ofaxis or associated anomalous vertebral artery it may lead tothinning of lateral mass and pedicle would prevent adequatefixation of transpedicular screw and vertebral artery will alsobe at risk [2]

Therefore the present study was designed to know thedimensions of lateral masses of axis that are important toanalyze their relationship with the vertebral artery and alsoto determine the ideal drill angle for accurate placementof a screw in the area resulting from fracture or partial

Hindawi Publishing CorporationAnatomy Research InternationalVolume 2014 Article ID 425868 9 pageshttpdxdoiorg1011552014425868

2 Anatomy Research International

E

F

e fE998400

F998400

(a)

IJ

K

L

(b)

i

jk

ll

(c)

Figure 1 (a) Superior view of axis showing pedicle length (PL = EF) pedicle height (PH = E1015840F1015840) and pedicle width (PW = ef) (b) Lateralview of axis showing superior articular facet length (SAFL = IJ) and width (SAFW = KL) (c) Anterior view of axis showing inferior articularfacet length (IAFL = ij) and width (IAFW = kl)

S

T

(a)

s

t

(b)

Figure 2 (a) Anterior view of axis showing superior articular facet external height (ST = SAFHE) (b) Superior view of axis showing superiorarticular facet internal height (SAFHI = st)

sublaxation [4] Thus it would be essential for the cliniciansand surgeons to have a proper orientation of the anatomydimensions and special features of this unique vertebra

2 Material and Methods

The study was conducted on 60 dry axis vertebrae obtained inthe Department of Anatomy Government Medical CollegeAmritsar The measured parameters included dimensionsregarding lateral masses of axis vertebrae focused on pediclesuperior articular facet inferior articular facet foramentransversarium and pedicle angles Fifteen parameters weremeasured and all the measurements were made using avernier caliper accurate to 01mmThe angles were measuredby using an iron wire scale and a protractor Based uponlinear and angular parameters the mean range and standarddeviation were calculated The statistical analysis of themeasurements of right and left sides was also done (Table 1and Figures 1 2 3 4 and 5)

Tomeasure the angles first point of pedicle axis projectionwould be definedwhichwas determined by drawing two linesparallel to the axis one on superior surface of the pedicle

and the other on medial side of the pedicle These two linesintersected on the posterior aspect of the lateral mass

3 Results

Themeasurements of all parts of lateral mass of axis vertebraeincluding the angles showed uniformity and there was nosignificant statistical difference observed in the mean dimen-sions of the parameters measured The pediclelength widthand height were 2161 plusmn 237mm 882 plusmn 243mm and 563 plusmn206mm respectively Length and width of superior articularfacet were 1634 plusmn 156mm and 1435 plusmn 175mm Externaland internal height were 898 plusmn 136mm and 423 plusmn 081mmThus 472plusmn 083mm is depth of vertebral artery calculated asthe difference between external and internal height Lengthand width of inferior articular facet were 1113 plusmn 143mmand 789 plusmn 130mm The foramen transversarium lengthwidth and depth were found to be 511 plusmn 091mm 506 plusmn123mm and 409 plusmn 074mm respectively Pedicle superiorangle was 233 degrees and pedicle median angle was 322degrees (Table 2)

Anatomy Research International 3

Table 1 The measured parameters

S number Parameters of lateral mass of axis vertebrae (pedicle SAF IAF FT and angles)

1 Pedicle length (PL) Length was measured from anterior most point of the pedicle axis to theposterior point of pedicle axis projection EF = PL (Figure 1(a))

2 Pedicle width (PW) It was taken from internal surface of pedicle to its external surface at thelevel of transverse foramen ef = PW (Figure 1(a))

3 Pedicle height (PH) It was measured from its superior surface to inferior surface with in theforamen transversarium E1015840F1015840 = PH (Figure 1(a))

4-5 Superior articular facet length(SAFL) and width (SAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of superior facet (IJ = SAFL) (KL = SAFW) (Figure 1(b))

6 External height (SAFHE)It was taken from upper midpoint on the superior articular surface to thelower midpoint on the inferior surface ST = SAFHE (Figure 2(a))

7 Internal height (SAFHI)It was taken from midpoint of articular surface to the nearest point on theinferior surface st = SAFHI (Figure 2(b))

8 Depth of vertebral artery It was taken as the difference between external and internal height

9-10 Inferior articular facet length(IAFL) and width (IAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of Inferior facet (ij = IAFL) (kl = IAFW) (Figure 1(c))

11ndash13Foramen transversarium length(FTL) width (FTW) and depth(FTD)

It is the maximum anteroposterior transverse and superoinferior diameter(MN = FTL) (mn = FTW) (OP = FTD) (Figures 3(a) and 3(b))

14 Pedicle superior angle (PSA) It was measured as the angle between the pedicle axis and a line drawnperpendicular to the body of the axis read as PSA (Figure 4)

15 Pedicle median angle (PMA)It was measured as the angle between the pedicle axis and line passingthrough the midline of the vertebral body and the spinous process and readas PMA (Figure 5)

M

Nm n

(a)

O

P

(b)

Figure 3 (a) Superior view of axis showing foramen transversarium length (FTL = MN) and width (FTW = mn) (b) Superior view of axisshowing foramen transversarium depth (FTD = OP)

4 Discussion

Detailed knowledge of pedicle would be essential iftranspedicular screw placement is desired to stabilize afracture line through 119862

2pedicle [4 14 15] Pedicle angles

represent the safe bounds for transpedicular screw fixationA glance at Table 3 elucidates that in the present study

the parameters of pedicle length pedicle width and pedicleheight of right and left sideswere compared andno significantstatistical difference was observed in the mean dimension

of the parameters studied on the two sides of the vertebraeNone of the earlier authors have compared the parametersof both the sides in the available accessible literature andthe difference of mean of pedicle length (PL) was (119875 =0872) width (PW) was (119875 = 0895) and height (PH) was(119875 = 0886) respectively which was found to be statisticallyinsignificant

The values of superior articular facet external height(SAFHE) reported in the present study stood equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9] and

4 Anatomy Research International

Table 2 Results of measured parameters of lateral mass of axis vertebra

S number Parameters (mm) Mean SD Range 119875 value1 Pedicle length (PL) 2161 237 1600ndash2515 08722 Pedicle width (PW) 882 206 360ndash1250 08953 Pedicle height (PH) 563 243 220ndash1395 08864 Superior articular facet length (SAFL) 1634 156 1390ndash2070 01415 Superior articular facet width (SAFW) 1435 175 1140ndash1770 06616 Superior articular facet external height (SAFHe) 898 136 58ndash1205 04887 Superior articular facet internal height (SAFHi) 423 081 240ndash660 06208 Depth of vertebral artery 472 083 240ndash605 02339 Inferior articular facet length (IAFL) 1113 143 880ndash1450 027410 Inferior articular facet width (IAFW) 789 130 670ndash1020 068111 Foramen transversarium length (FTL) 511 091 275ndash650 048212 Foramen transversarium width (FTW) 506 123 325ndash800 066213 Foramen transversarium depth (FTD) 409 074 270ndash530 064514 Pedicle superior angle (PSA) 2332 262 1900ndash2900 037815 Pedicle median angle (PMA) 3223 165 2900ndash3600 0211

PSA

(a)

PSA

PH

DVA

(b)

Figure 4 Showing superior angle of pedicle axis projection marked as PSA

the values of right and left sides were also calculated and thedifference between mean dimensions of external height ofboth the sides was observed to be statistically insignificant(119875 = 0488) whereas the superior articular facet internalheight (SAFHI) in the present study stand equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9]and the difference between the mean dimensions of internalheight of right and left sides was also found to be statisticallyinsignificant (119875 = 0620) It is also interpreted in Table 3that the findings of depth of vertebral artery in the presentstudy stands equivalent toMadawi et al (1997) [2] and Guptaand Goel (2000) [9] and are statistically not significant (119875 =0233)

A glance at Table 3 also showed that in the present studythe difference of mean of foramen transversarium length(FTL) was (119875 = 0482) width (FTW) was (119875 = 0662) anddepth was (FTD) (119875 = 0645) respectively which was foundto be statistically insignificant and also these parametersshowed nomajor differencewhen comparedwith theworkersreported in the literature The pedicle superior angle (PSA)in the present study was slightly less as compared with work

done by Madawi et al (1997) [2] and more to Xu et al (1995)[4] No significant statistical difference was observed in themean dimension of the angles studied on the two sides ofthe vertebrae (119875 = 0378) whereas the pedicle median angle(PMA) was in accordance to the work done by Xu et al (1995)[4] and Madawi et al (1997) [2] No significant statisticaldifference was observed in the mean dimension of the anglesstudied on the two sides of the vertebrae (119875 = 0211)

A glance at Table 4 in the present study the length ofsuperior articular facet (SAFL) in North Indian populationshowed very slight difference when compared with the studyof Francis (1955) [13] Xu et al (1995) [4] and Gupta andGoel (2000) [9] The difference between the mean of lengthof right and left superior articular facet of axis was foundto be statistically insignificant (119875 = 0141) and width ofSAF (SAFW) in North Indian population showed very slightdifference when compared with the study of Francis (1955)[13] Xu et al (1995) [4] and Gupta and Goel (2000) [9] Thedifference between mean of width of right and left superiorarticular facet of axis was found to be statistically insignificant(119875 = 0661)

Anatomy Research International 5

Table3Com

paris

onof

results

repo

rted

inthep

resent

study

andserie

sreportedin

theliterature

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PL2161plusmn

237

1600ndash

2515

Male(30)

256plusmn18

23ndash31

Female(20)

255plusmn14

23ndash29

287plusmn22

22ndash36

mdash166

mdash

PW882plusmn206

360ndash1250

Male(30)

77plusmn14

5ndash10

Female(20)

9plusmn11

4ndash10

79plusmn15

47ndash124

79 48ndash145

91mdash

PH563plusmn243

220ndash1395

Male(30)

86plusmn12

6ndash12

Female(20)

79plusmn14

6ndash10

78plusmn13

34ndash

122

77 45ndash12

79mdash

SAFH

E

Rt 887plusmn16

355ndash1390

Lt 90

8plusmn15

156ndash

1330

Mean 898plusmn13

658ndash1205

mdash86plusmn14

53ndash123

84

55ndash115

mdashmdash

SAFH

i

Rt 427plusmn088

270ndash6

50

Lt 4

21plusmn086

220ndash710

Mean 423plusmn081

240

ndash660

mdash44plusmn18

08ndash90

462

15ndash85

mdashmdash

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

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2 Anatomy Research International

E

F

e fE998400

F998400

(a)

IJ

K

L

(b)

i

jk

ll

(c)

Figure 1 (a) Superior view of axis showing pedicle length (PL = EF) pedicle height (PH = E1015840F1015840) and pedicle width (PW = ef) (b) Lateralview of axis showing superior articular facet length (SAFL = IJ) and width (SAFW = KL) (c) Anterior view of axis showing inferior articularfacet length (IAFL = ij) and width (IAFW = kl)

S

T

(a)

s

t

(b)

Figure 2 (a) Anterior view of axis showing superior articular facet external height (ST = SAFHE) (b) Superior view of axis showing superiorarticular facet internal height (SAFHI = st)

sublaxation [4] Thus it would be essential for the cliniciansand surgeons to have a proper orientation of the anatomydimensions and special features of this unique vertebra

2 Material and Methods

The study was conducted on 60 dry axis vertebrae obtained inthe Department of Anatomy Government Medical CollegeAmritsar The measured parameters included dimensionsregarding lateral masses of axis vertebrae focused on pediclesuperior articular facet inferior articular facet foramentransversarium and pedicle angles Fifteen parameters weremeasured and all the measurements were made using avernier caliper accurate to 01mmThe angles were measuredby using an iron wire scale and a protractor Based uponlinear and angular parameters the mean range and standarddeviation were calculated The statistical analysis of themeasurements of right and left sides was also done (Table 1and Figures 1 2 3 4 and 5)

Tomeasure the angles first point of pedicle axis projectionwould be definedwhichwas determined by drawing two linesparallel to the axis one on superior surface of the pedicle

and the other on medial side of the pedicle These two linesintersected on the posterior aspect of the lateral mass

3 Results

Themeasurements of all parts of lateral mass of axis vertebraeincluding the angles showed uniformity and there was nosignificant statistical difference observed in the mean dimen-sions of the parameters measured The pediclelength widthand height were 2161 plusmn 237mm 882 plusmn 243mm and 563 plusmn206mm respectively Length and width of superior articularfacet were 1634 plusmn 156mm and 1435 plusmn 175mm Externaland internal height were 898 plusmn 136mm and 423 plusmn 081mmThus 472plusmn 083mm is depth of vertebral artery calculated asthe difference between external and internal height Lengthand width of inferior articular facet were 1113 plusmn 143mmand 789 plusmn 130mm The foramen transversarium lengthwidth and depth were found to be 511 plusmn 091mm 506 plusmn123mm and 409 plusmn 074mm respectively Pedicle superiorangle was 233 degrees and pedicle median angle was 322degrees (Table 2)

Anatomy Research International 3

Table 1 The measured parameters

S number Parameters of lateral mass of axis vertebrae (pedicle SAF IAF FT and angles)

1 Pedicle length (PL) Length was measured from anterior most point of the pedicle axis to theposterior point of pedicle axis projection EF = PL (Figure 1(a))

2 Pedicle width (PW) It was taken from internal surface of pedicle to its external surface at thelevel of transverse foramen ef = PW (Figure 1(a))

3 Pedicle height (PH) It was measured from its superior surface to inferior surface with in theforamen transversarium E1015840F1015840 = PH (Figure 1(a))

4-5 Superior articular facet length(SAFL) and width (SAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of superior facet (IJ = SAFL) (KL = SAFW) (Figure 1(b))

6 External height (SAFHE)It was taken from upper midpoint on the superior articular surface to thelower midpoint on the inferior surface ST = SAFHE (Figure 2(a))

7 Internal height (SAFHI)It was taken from midpoint of articular surface to the nearest point on theinferior surface st = SAFHI (Figure 2(b))

8 Depth of vertebral artery It was taken as the difference between external and internal height

9-10 Inferior articular facet length(IAFL) and width (IAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of Inferior facet (ij = IAFL) (kl = IAFW) (Figure 1(c))

11ndash13Foramen transversarium length(FTL) width (FTW) and depth(FTD)

It is the maximum anteroposterior transverse and superoinferior diameter(MN = FTL) (mn = FTW) (OP = FTD) (Figures 3(a) and 3(b))

14 Pedicle superior angle (PSA) It was measured as the angle between the pedicle axis and a line drawnperpendicular to the body of the axis read as PSA (Figure 4)

15 Pedicle median angle (PMA)It was measured as the angle between the pedicle axis and line passingthrough the midline of the vertebral body and the spinous process and readas PMA (Figure 5)

M

Nm n

(a)

O

P

(b)

Figure 3 (a) Superior view of axis showing foramen transversarium length (FTL = MN) and width (FTW = mn) (b) Superior view of axisshowing foramen transversarium depth (FTD = OP)

4 Discussion

Detailed knowledge of pedicle would be essential iftranspedicular screw placement is desired to stabilize afracture line through 119862

2pedicle [4 14 15] Pedicle angles

represent the safe bounds for transpedicular screw fixationA glance at Table 3 elucidates that in the present study

the parameters of pedicle length pedicle width and pedicleheight of right and left sideswere compared andno significantstatistical difference was observed in the mean dimension

of the parameters studied on the two sides of the vertebraeNone of the earlier authors have compared the parametersof both the sides in the available accessible literature andthe difference of mean of pedicle length (PL) was (119875 =0872) width (PW) was (119875 = 0895) and height (PH) was(119875 = 0886) respectively which was found to be statisticallyinsignificant

The values of superior articular facet external height(SAFHE) reported in the present study stood equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9] and

4 Anatomy Research International

Table 2 Results of measured parameters of lateral mass of axis vertebra

S number Parameters (mm) Mean SD Range 119875 value1 Pedicle length (PL) 2161 237 1600ndash2515 08722 Pedicle width (PW) 882 206 360ndash1250 08953 Pedicle height (PH) 563 243 220ndash1395 08864 Superior articular facet length (SAFL) 1634 156 1390ndash2070 01415 Superior articular facet width (SAFW) 1435 175 1140ndash1770 06616 Superior articular facet external height (SAFHe) 898 136 58ndash1205 04887 Superior articular facet internal height (SAFHi) 423 081 240ndash660 06208 Depth of vertebral artery 472 083 240ndash605 02339 Inferior articular facet length (IAFL) 1113 143 880ndash1450 027410 Inferior articular facet width (IAFW) 789 130 670ndash1020 068111 Foramen transversarium length (FTL) 511 091 275ndash650 048212 Foramen transversarium width (FTW) 506 123 325ndash800 066213 Foramen transversarium depth (FTD) 409 074 270ndash530 064514 Pedicle superior angle (PSA) 2332 262 1900ndash2900 037815 Pedicle median angle (PMA) 3223 165 2900ndash3600 0211

PSA

(a)

PSA

PH

DVA

(b)

Figure 4 Showing superior angle of pedicle axis projection marked as PSA

the values of right and left sides were also calculated and thedifference between mean dimensions of external height ofboth the sides was observed to be statistically insignificant(119875 = 0488) whereas the superior articular facet internalheight (SAFHI) in the present study stand equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9]and the difference between the mean dimensions of internalheight of right and left sides was also found to be statisticallyinsignificant (119875 = 0620) It is also interpreted in Table 3that the findings of depth of vertebral artery in the presentstudy stands equivalent toMadawi et al (1997) [2] and Guptaand Goel (2000) [9] and are statistically not significant (119875 =0233)

A glance at Table 3 also showed that in the present studythe difference of mean of foramen transversarium length(FTL) was (119875 = 0482) width (FTW) was (119875 = 0662) anddepth was (FTD) (119875 = 0645) respectively which was foundto be statistically insignificant and also these parametersshowed nomajor differencewhen comparedwith theworkersreported in the literature The pedicle superior angle (PSA)in the present study was slightly less as compared with work

done by Madawi et al (1997) [2] and more to Xu et al (1995)[4] No significant statistical difference was observed in themean dimension of the angles studied on the two sides ofthe vertebrae (119875 = 0378) whereas the pedicle median angle(PMA) was in accordance to the work done by Xu et al (1995)[4] and Madawi et al (1997) [2] No significant statisticaldifference was observed in the mean dimension of the anglesstudied on the two sides of the vertebrae (119875 = 0211)

A glance at Table 4 in the present study the length ofsuperior articular facet (SAFL) in North Indian populationshowed very slight difference when compared with the studyof Francis (1955) [13] Xu et al (1995) [4] and Gupta andGoel (2000) [9] The difference between the mean of lengthof right and left superior articular facet of axis was foundto be statistically insignificant (119875 = 0141) and width ofSAF (SAFW) in North Indian population showed very slightdifference when compared with the study of Francis (1955)[13] Xu et al (1995) [4] and Gupta and Goel (2000) [9] Thedifference between mean of width of right and left superiorarticular facet of axis was found to be statistically insignificant(119875 = 0661)

Anatomy Research International 5

Table3Com

paris

onof

results

repo

rted

inthep

resent

study

andserie

sreportedin

theliterature

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PL2161plusmn

237

1600ndash

2515

Male(30)

256plusmn18

23ndash31

Female(20)

255plusmn14

23ndash29

287plusmn22

22ndash36

mdash166

mdash

PW882plusmn206

360ndash1250

Male(30)

77plusmn14

5ndash10

Female(20)

9plusmn11

4ndash10

79plusmn15

47ndash124

79 48ndash145

91mdash

PH563plusmn243

220ndash1395

Male(30)

86plusmn12

6ndash12

Female(20)

79plusmn14

6ndash10

78plusmn13

34ndash

122

77 45ndash12

79mdash

SAFH

E

Rt 887plusmn16

355ndash1390

Lt 90

8plusmn15

156ndash

1330

Mean 898plusmn13

658ndash1205

mdash86plusmn14

53ndash123

84

55ndash115

mdashmdash

SAFH

i

Rt 427plusmn088

270ndash6

50

Lt 4

21plusmn086

220ndash710

Mean 423plusmn081

240

ndash660

mdash44plusmn18

08ndash90

462

15ndash85

mdashmdash

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

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Volume 2014

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Molecular Biology International

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International Journal of

Microbiology

Anatomy Research International 3

Table 1 The measured parameters

S number Parameters of lateral mass of axis vertebrae (pedicle SAF IAF FT and angles)

1 Pedicle length (PL) Length was measured from anterior most point of the pedicle axis to theposterior point of pedicle axis projection EF = PL (Figure 1(a))

2 Pedicle width (PW) It was taken from internal surface of pedicle to its external surface at thelevel of transverse foramen ef = PW (Figure 1(a))

3 Pedicle height (PH) It was measured from its superior surface to inferior surface with in theforamen transversarium E1015840F1015840 = PH (Figure 1(a))

4-5 Superior articular facet length(SAFL) and width (SAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of superior facet (IJ = SAFL) (KL = SAFW) (Figure 1(b))

6 External height (SAFHE)It was taken from upper midpoint on the superior articular surface to thelower midpoint on the inferior surface ST = SAFHE (Figure 2(a))

7 Internal height (SAFHI)It was taken from midpoint of articular surface to the nearest point on theinferior surface st = SAFHI (Figure 2(b))

8 Depth of vertebral artery It was taken as the difference between external and internal height

9-10 Inferior articular facet length(IAFL) and width (IAFW)

It is the maximum anteroposterior and transverse diameter of articularsurface of Inferior facet (ij = IAFL) (kl = IAFW) (Figure 1(c))

11ndash13Foramen transversarium length(FTL) width (FTW) and depth(FTD)

It is the maximum anteroposterior transverse and superoinferior diameter(MN = FTL) (mn = FTW) (OP = FTD) (Figures 3(a) and 3(b))

14 Pedicle superior angle (PSA) It was measured as the angle between the pedicle axis and a line drawnperpendicular to the body of the axis read as PSA (Figure 4)

15 Pedicle median angle (PMA)It was measured as the angle between the pedicle axis and line passingthrough the midline of the vertebral body and the spinous process and readas PMA (Figure 5)

M

Nm n

(a)

O

P

(b)

Figure 3 (a) Superior view of axis showing foramen transversarium length (FTL = MN) and width (FTW = mn) (b) Superior view of axisshowing foramen transversarium depth (FTD = OP)

4 Discussion

Detailed knowledge of pedicle would be essential iftranspedicular screw placement is desired to stabilize afracture line through 119862

2pedicle [4 14 15] Pedicle angles

represent the safe bounds for transpedicular screw fixationA glance at Table 3 elucidates that in the present study

the parameters of pedicle length pedicle width and pedicleheight of right and left sideswere compared andno significantstatistical difference was observed in the mean dimension

of the parameters studied on the two sides of the vertebraeNone of the earlier authors have compared the parametersof both the sides in the available accessible literature andthe difference of mean of pedicle length (PL) was (119875 =0872) width (PW) was (119875 = 0895) and height (PH) was(119875 = 0886) respectively which was found to be statisticallyinsignificant

The values of superior articular facet external height(SAFHE) reported in the present study stood equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9] and

4 Anatomy Research International

Table 2 Results of measured parameters of lateral mass of axis vertebra

S number Parameters (mm) Mean SD Range 119875 value1 Pedicle length (PL) 2161 237 1600ndash2515 08722 Pedicle width (PW) 882 206 360ndash1250 08953 Pedicle height (PH) 563 243 220ndash1395 08864 Superior articular facet length (SAFL) 1634 156 1390ndash2070 01415 Superior articular facet width (SAFW) 1435 175 1140ndash1770 06616 Superior articular facet external height (SAFHe) 898 136 58ndash1205 04887 Superior articular facet internal height (SAFHi) 423 081 240ndash660 06208 Depth of vertebral artery 472 083 240ndash605 02339 Inferior articular facet length (IAFL) 1113 143 880ndash1450 027410 Inferior articular facet width (IAFW) 789 130 670ndash1020 068111 Foramen transversarium length (FTL) 511 091 275ndash650 048212 Foramen transversarium width (FTW) 506 123 325ndash800 066213 Foramen transversarium depth (FTD) 409 074 270ndash530 064514 Pedicle superior angle (PSA) 2332 262 1900ndash2900 037815 Pedicle median angle (PMA) 3223 165 2900ndash3600 0211

PSA

(a)

PSA

PH

DVA

(b)

Figure 4 Showing superior angle of pedicle axis projection marked as PSA

the values of right and left sides were also calculated and thedifference between mean dimensions of external height ofboth the sides was observed to be statistically insignificant(119875 = 0488) whereas the superior articular facet internalheight (SAFHI) in the present study stand equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9]and the difference between the mean dimensions of internalheight of right and left sides was also found to be statisticallyinsignificant (119875 = 0620) It is also interpreted in Table 3that the findings of depth of vertebral artery in the presentstudy stands equivalent toMadawi et al (1997) [2] and Guptaand Goel (2000) [9] and are statistically not significant (119875 =0233)

A glance at Table 3 also showed that in the present studythe difference of mean of foramen transversarium length(FTL) was (119875 = 0482) width (FTW) was (119875 = 0662) anddepth was (FTD) (119875 = 0645) respectively which was foundto be statistically insignificant and also these parametersshowed nomajor differencewhen comparedwith theworkersreported in the literature The pedicle superior angle (PSA)in the present study was slightly less as compared with work

done by Madawi et al (1997) [2] and more to Xu et al (1995)[4] No significant statistical difference was observed in themean dimension of the angles studied on the two sides ofthe vertebrae (119875 = 0378) whereas the pedicle median angle(PMA) was in accordance to the work done by Xu et al (1995)[4] and Madawi et al (1997) [2] No significant statisticaldifference was observed in the mean dimension of the anglesstudied on the two sides of the vertebrae (119875 = 0211)

A glance at Table 4 in the present study the length ofsuperior articular facet (SAFL) in North Indian populationshowed very slight difference when compared with the studyof Francis (1955) [13] Xu et al (1995) [4] and Gupta andGoel (2000) [9] The difference between the mean of lengthof right and left superior articular facet of axis was foundto be statistically insignificant (119875 = 0141) and width ofSAF (SAFW) in North Indian population showed very slightdifference when compared with the study of Francis (1955)[13] Xu et al (1995) [4] and Gupta and Goel (2000) [9] Thedifference between mean of width of right and left superiorarticular facet of axis was found to be statistically insignificant(119875 = 0661)

Anatomy Research International 5

Table3Com

paris

onof

results

repo

rted

inthep

resent

study

andserie

sreportedin

theliterature

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PL2161plusmn

237

1600ndash

2515

Male(30)

256plusmn18

23ndash31

Female(20)

255plusmn14

23ndash29

287plusmn22

22ndash36

mdash166

mdash

PW882plusmn206

360ndash1250

Male(30)

77plusmn14

5ndash10

Female(20)

9plusmn11

4ndash10

79plusmn15

47ndash124

79 48ndash145

91mdash

PH563plusmn243

220ndash1395

Male(30)

86plusmn12

6ndash12

Female(20)

79plusmn14

6ndash10

78plusmn13

34ndash

122

77 45ndash12

79mdash

SAFH

E

Rt 887plusmn16

355ndash1390

Lt 90

8plusmn15

156ndash

1330

Mean 898plusmn13

658ndash1205

mdash86plusmn14

53ndash123

84

55ndash115

mdashmdash

SAFH

i

Rt 427plusmn088

270ndash6

50

Lt 4

21plusmn086

220ndash710

Mean 423plusmn081

240

ndash660

mdash44plusmn18

08ndash90

462

15ndash85

mdashmdash

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

4 Anatomy Research International

Table 2 Results of measured parameters of lateral mass of axis vertebra

S number Parameters (mm) Mean SD Range 119875 value1 Pedicle length (PL) 2161 237 1600ndash2515 08722 Pedicle width (PW) 882 206 360ndash1250 08953 Pedicle height (PH) 563 243 220ndash1395 08864 Superior articular facet length (SAFL) 1634 156 1390ndash2070 01415 Superior articular facet width (SAFW) 1435 175 1140ndash1770 06616 Superior articular facet external height (SAFHe) 898 136 58ndash1205 04887 Superior articular facet internal height (SAFHi) 423 081 240ndash660 06208 Depth of vertebral artery 472 083 240ndash605 02339 Inferior articular facet length (IAFL) 1113 143 880ndash1450 027410 Inferior articular facet width (IAFW) 789 130 670ndash1020 068111 Foramen transversarium length (FTL) 511 091 275ndash650 048212 Foramen transversarium width (FTW) 506 123 325ndash800 066213 Foramen transversarium depth (FTD) 409 074 270ndash530 064514 Pedicle superior angle (PSA) 2332 262 1900ndash2900 037815 Pedicle median angle (PMA) 3223 165 2900ndash3600 0211

PSA

(a)

PSA

PH

DVA

(b)

Figure 4 Showing superior angle of pedicle axis projection marked as PSA

the values of right and left sides were also calculated and thedifference between mean dimensions of external height ofboth the sides was observed to be statistically insignificant(119875 = 0488) whereas the superior articular facet internalheight (SAFHI) in the present study stand equivalent toMadawi et al (1997) [2] and Gupta and Goel (2000) [9]and the difference between the mean dimensions of internalheight of right and left sides was also found to be statisticallyinsignificant (119875 = 0620) It is also interpreted in Table 3that the findings of depth of vertebral artery in the presentstudy stands equivalent toMadawi et al (1997) [2] and Guptaand Goel (2000) [9] and are statistically not significant (119875 =0233)

A glance at Table 3 also showed that in the present studythe difference of mean of foramen transversarium length(FTL) was (119875 = 0482) width (FTW) was (119875 = 0662) anddepth was (FTD) (119875 = 0645) respectively which was foundto be statistically insignificant and also these parametersshowed nomajor differencewhen comparedwith theworkersreported in the literature The pedicle superior angle (PSA)in the present study was slightly less as compared with work

done by Madawi et al (1997) [2] and more to Xu et al (1995)[4] No significant statistical difference was observed in themean dimension of the angles studied on the two sides ofthe vertebrae (119875 = 0378) whereas the pedicle median angle(PMA) was in accordance to the work done by Xu et al (1995)[4] and Madawi et al (1997) [2] No significant statisticaldifference was observed in the mean dimension of the anglesstudied on the two sides of the vertebrae (119875 = 0211)

A glance at Table 4 in the present study the length ofsuperior articular facet (SAFL) in North Indian populationshowed very slight difference when compared with the studyof Francis (1955) [13] Xu et al (1995) [4] and Gupta andGoel (2000) [9] The difference between the mean of lengthof right and left superior articular facet of axis was foundto be statistically insignificant (119875 = 0141) and width ofSAF (SAFW) in North Indian population showed very slightdifference when compared with the study of Francis (1955)[13] Xu et al (1995) [4] and Gupta and Goel (2000) [9] Thedifference between mean of width of right and left superiorarticular facet of axis was found to be statistically insignificant(119875 = 0661)

Anatomy Research International 5

Table3Com

paris

onof

results

repo

rted

inthep

resent

study

andserie

sreportedin

theliterature

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PL2161plusmn

237

1600ndash

2515

Male(30)

256plusmn18

23ndash31

Female(20)

255plusmn14

23ndash29

287plusmn22

22ndash36

mdash166

mdash

PW882plusmn206

360ndash1250

Male(30)

77plusmn14

5ndash10

Female(20)

9plusmn11

4ndash10

79plusmn15

47ndash124

79 48ndash145

91mdash

PH563plusmn243

220ndash1395

Male(30)

86plusmn12

6ndash12

Female(20)

79plusmn14

6ndash10

78plusmn13

34ndash

122

77 45ndash12

79mdash

SAFH

E

Rt 887plusmn16

355ndash1390

Lt 90

8plusmn15

156ndash

1330

Mean 898plusmn13

658ndash1205

mdash86plusmn14

53ndash123

84

55ndash115

mdashmdash

SAFH

i

Rt 427plusmn088

270ndash6

50

Lt 4

21plusmn086

220ndash710

Mean 423plusmn081

240

ndash660

mdash44plusmn18

08ndash90

462

15ndash85

mdashmdash

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

Anatomy Research International 5

Table3Com

paris

onof

results

repo

rted

inthep

resent

study

andserie

sreportedin

theliterature

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PL2161plusmn

237

1600ndash

2515

Male(30)

256plusmn18

23ndash31

Female(20)

255plusmn14

23ndash29

287plusmn22

22ndash36

mdash166

mdash

PW882plusmn206

360ndash1250

Male(30)

77plusmn14

5ndash10

Female(20)

9plusmn11

4ndash10

79plusmn15

47ndash124

79 48ndash145

91mdash

PH563plusmn243

220ndash1395

Male(30)

86plusmn12

6ndash12

Female(20)

79plusmn14

6ndash10

78plusmn13

34ndash

122

77 45ndash12

79mdash

SAFH

E

Rt 887plusmn16

355ndash1390

Lt 90

8plusmn15

156ndash

1330

Mean 898plusmn13

658ndash1205

mdash86plusmn14

53ndash123

84

55ndash115

mdashmdash

SAFH

i

Rt 427plusmn088

270ndash6

50

Lt 4

21plusmn086

220ndash710

Mean 423plusmn081

240

ndash660

mdash44plusmn18

08ndash90

462

15ndash85

mdashmdash

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

6 Anatomy Research International

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Depth

ofvertebral

artery

Rt 4

61plusmn10

9260ndash740

Lt 4

87plusmn095

220ndash6

60

Mean 472plusmn083

240

ndash605

mdash42plusmn16

10ndash94

436

20ndash

82

mdashmdash

FTL

Rt 503plusmn10

7300ndash700

Lt 518plusmn10

915

0ndash70

0Mean 511plusmn091

275ndash6

50

mdashmdash

mdashmdash

Rt 585plusmn13

939ndash

113

Lt 576plusmn071

40ndash

73

FTW

Rt 512plusmn13

2300ndash800

Lt 500plusmn15

3200ndash800

Mean 506plusmn12

3325ndash800

mdash56plusmn09

43ndash80

mdashmdash

Rt 477plusmn070

36ndash

62

Lt 4

99plusmn066

34ndash

60

FTD

Rt 413plusmn087

250ndash580

Lt 4

05plusmn089

240

ndash580

Mean 409plusmn074

270ndash530

mdash57plusmn10

39ndash

90mdash

mdashmdash

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

Anatomy Research International 7

Table3Con

tinued

Parameters

Lalit

etal(present

study)2

014

North

Indian

60

Xuetal1995[4]

Ohio50

Madaw

ietal1997

[2]

England50

Gup

taandGoel

2000

[9]

Maharashtria

n50

How

ington

etal2001

[11]

American

10

Taitz

etal1978[12]

Israel32

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

Mean(m

m)a

ndSD

range(mm)

PSA

Rt 23

40plusmn263

1900ndash

2900

Lt 23

23plusmn271

1900ndash

2900

Mean 2332plusmn262

1900ndash

2900

Male(30)

204plusmn40

14ndash30

Female(20)

200plusmn38

13ndash25

240plusmn42

13ndash34

mdashmdash

mdash

PMA

Rt 32

10plusmn19

52900ndash

3700

Lt 32

37plusmn15

22900ndash

3600

Mean 3223plusmn16

52900ndash

3600

Male(30)

333plusmn29

26ndash4

0Female(20)

327plusmn34

28ndash4

1

324plusmn40

24ndash4

3mdash

mdashmdash

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

8 Anatomy Research International

PMA

(a)

PMA

(b)

Figure 5 Showing median angle of pedicle axis marked as PMA

Table 4 Comparison of superior and inferior articular facets length and width of axis vertebrae

Worker andyear Population

SAFLmean (mm) and SDrange (mm)

SAFWmean (mm) and SDrange (mm)

IAFLmean (mm) and SDrange (mm)

IAFWmean (mm) and SDrange (mm)

Francis 1955[13]

White males 109

Rt188 plusmn 1615ndash23

Lt187 plusmn 1515ndash23

Rt167 plusmn 1614ndash22

Lt183 plusmn 1715ndash23

Rt110 plusmn 178ndash18

Lt113 plusmn 159ndash16

Rt119 plusmn 149ndash16

Lt121 plusmn 159ndash17

White females27

Rt180 plusmn 1814ndash20

Lt174 plusmn 1414ndash20

Rt151 plusmn 1313ndash18

Lt167 plusmn 1712ndash20

Rt116 plusmn 139ndash14

Lt111 plusmn 149ndash14

Rt107 plusmn 119ndash13

Lt114 plusmn 1210ndash15

Negro males 135

Rt190 plusmn 1316ndash22

Lt189 plusmn 1516ndash22

Rt177 plusmn 1415ndash21

Lt179 plusmn 1415ndash21

Rt120 plusmn 179ndash16

Lt114 plusmn 188ndash16

Rt113 plusmn 168ndash15

Lt118 plusmn 149ndash15

Negro females57

Rt176 plusmn 1315ndash20

Lt177 plusmn 1515ndash21

Rt157 plusmn 1114ndash18

Lt161 plusmn 1413ndash19

Rt112 plusmn 119ndash13

Lt110 plusmn 129ndash14

Rt107 plusmn 119ndash14

Lt111 plusmn 119ndash13

Xu et al 1995[4]

Ohio males 30 182 plusmn 1516ndash23

176 plusmn 1316ndash21 mdash mdash

Ohio females 20 171 plusmn 1115ndash19

169 plusmn 1314ndash19 mdash mdash

Gupta andGoel 2000 [9]

Maharashtrian50

16513ndash205

15912ndash195

10597ndash15

9586ndash15

Lalit et al(PresentStudy) 2014

North Indians60

Rt1649 plusmn 1611390ndash2050

Lt1618 plusmn 1701350ndash2090

Mean634 plusmn 1561390ndash2070

Rt1439 plusmn 2011100ndash1820

Lt1431 plusmn 1621140ndash1730

Mean1435 plusmn 1751140ndash1770

Rt1126 plusmn 146870ndash1400

Lt1099 plusmn 168780ndash1500

Mean1113 plusmn 143880ndash1450

Rt783 plusmn 127580ndash1180

Lt794 plusmn 164480ndash1240

Mean789 plusmn 130670ndash1020

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

Anatomy Research International 9

Values of inferior articular facet length of axis (IAFL) inthe present study stood equivalent whereas inferior articularfacet width (IAFW) was found to be less when comparedwith work done by Francis (1955) [13] and Gupta and Goel(2000) [9] But the comparison of right and left sides wasnot specified by them No significant statistical difference wasobserved in themean dimension of the IAFL (119875 = 0274) andIAFW (119875 = 0681) studied on the two sides of the vertebrae

5 Conclusions

The study may provide information for the surgeons todetermine the safe site of entry and trajectory for the screwimplantation and also toavoid injuries to vital structureswhile operating around axis Dimensions of axis vertebralforamen transversarium are important and act as a usefulguide in the estimation of dilation of vertebral artery Thevertebral artery and the basilar artery contribute bloodsupply not only to the brain but to inner ear also and theircompression may lead to irritation of sympathetic plexusmanifested not only by neurological symptoms but also bylabyrinthine or hearing disturbancesThus dimensions of axisvertebral foramen transversarium are important and act as auseful guide in the estimation of dilation of vertebral artery[12 16 17] SAFof axis has a crucial relationshipwith vertebralartery that makes the vertebral artery more prone to injuryAsymmetry of articular processes in particular hypertrophyof articular processes might have caused torticollis withsevere constriction of cervical mobility [18] To determineaccurate placement of a screw in the area of any deformityresulting from fracture or partial sublaxation ideal drill anglefor transpedicular screw placement is required Thereforecareful anatomic reduction is essential [4 19]

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] M William R L M Newell and P Collin ldquoThe back cervicalvertebraerdquo in Grayrsquos Anatomy S Standring H Ellis J CHaely and A Williams Eds pp 742ndash746 Elsevier ChurchillLivingstone London UK 39th edition 2005

[2] A A Madawi G Solanki A T H Casey and H A CrockardldquoVariation of the groove in the axis vertebra for the vertebralarteryrdquo Journal of Bone and Joint Surgery B vol 79 no 5 pp820ndash823 1997

[3] M H Heggeness and B J Doherty ldquoThe trabecular anatomy ofthe axisrdquo Spine vol 18 no 14 pp 1945ndash1949 1993

[4] R Xu M C Nadaud N A Ebraheim and R A YeastingldquoMorphology of the second cervical vertebra and the posteriorprojection of the C

2pedicle axisrdquo Spine vol 20 no 3 pp 259ndash

263 1995[5] L Rogers ldquoSpine and spinal cordrdquo in Surgical Applied Anatomy

pp 505ndash513 Cassell and Company London UK 11th edition1947

[6] L M Overton and J W Grossman ldquoAnatomical variationsin the articulation between the second and third cervicalvertebraerdquo Journal of Bone and Joint Surgery vol 36 pp 155ndash161 1952

[7] C Taitz and B Arensburg ldquoVertebral artery tortuosity withconcomitant erosion of the foramen of the transverse processof the axis Possible clinical implicationsrdquo Acta Anatomica vol141 no 2 pp 104ndash108 1991

[8] B J Doherty and M H Heggeness ldquoThe quantitative anatomyof the atlasrdquo Spine vol 19 no 22 pp 2497ndash2500 1994

[9] S Gupta and A Goel ldquoQuantitative anatomy of the lateralmasses of the atlas and axis vertebraerdquo Neurology India vol 48no 2 pp 120ndash125 2000

[10] S T Dull R M Toselli E C Benzel and P R Cooper ldquoPreop-erative oblique axial computed tomographic imaging for C

1-C2

transarticular screw fixation Technical noterdquoNeurosurgery vol37 no 1 pp 150ndash152 1995

[11] J U Howington J J Kruse and D Awasthi ldquoSurgical anatomyof the C-2 pediclerdquo Journal of Neurosurgery vol 95 no 1 pp88ndash92 2001

[12] C Taitz H Nathan and B Arensburg ldquoAnatomical obser-vations of the foramina transversariardquo Journal of NeurologyNeurosurgery and Psychiatry vol 41 no 2 pp 170ndash176 1978

[13] C C Francis ldquoVariations in the articular facets of the cervicalvertebraerdquoThe Anatomical Record vol 122 no 4 pp 589ndash6021955

[14] R E Anderson and C N Shealy ldquoCervical pedicle erosionand rootlet compression caused by a tortuous vertebral arteryrdquoRadiology vol 96 no 3 pp 537ndash538 1970

[15] D F Cooper ldquoBone erosion of the cervical vertebrae secondaryto tortuosity of the vertebral artery case reportrdquo Journal ofNeurosurgery vol 53 no 1 pp 106ndash108 1980

[16] G I Wickbom and M R Williamson ldquoAnomalous foramentransversarium of C

2simulating erosion of bonerdquo Neuroradi-

ology vol 19 no 1 pp 43ndash45 1980[17] F Cacciola U Phalke and A Goel ldquoVertebral artery in rela-

tionship to C1-C2vertebrae an anatomical studyrdquo Neurology

vol 52 no 2 pp 178ndash184 2004[18] M Kawashima N Tanriover A L Rhoton A J Ulm and T

Matsushima ldquoExtreme lateral variants of the atlanto occipitaltransarticular approach to anterior extradural lesions of thecranio vertebral junctionmdashanatomic reportsrdquo Neurosurgeryvol 53 no 3 pp 662ndash675 2003

[19] M I Yusof L K Ming and M S Abdullah ldquoComputed tomo-graphic measurement of cervical pedicles for transpedicularfixation in a Malay populationrdquo Journal of Orthopaedic Surgeryvol 15 no 2 pp 187ndash190 2007

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 2014

Zoology

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology