55SProceedings of the NASS 22nd Annual Meeting / The Spine Journal 7 (2007) 1S–163S

PURPOSE: To examine the effectiveness of bilateral C4-5 foraminotomies

performed at time of open-door laminoplasty in preventing postoperative

C5 palsy and to determine if factors could be identified in case of failure.

STUDY DESIGN/SETTING: Retrospective

PATIENT SAMPLE: Patients who had bilateral C4-5 foraminotomy and

open-door laminoplasty performed by a single surgeon were enrolled.

OUTCOME MEASURES: Development of postoperative C5 palsy.

METHODS: Medical records were reviewed by independent surgeons un-

involved in the care of the patients with attention to patient clinical param-

eters, radiological findings and operative reports. Fischer’s Exact test and

General linear Model analyses were used to identify potential risk factors

for any C5 palsy development.

RESULTS: A total of 70 patients underwent bilateral C4-5 foraminoto-

mies and open-door laminoplasty. Average patient age at operation was

56(30-86)years. 54 male & 16 female were included. 87% of patients

presented with myelopathy and 13% with multilevel radiculopathies.

76% had spondylotic pathologies and 21% had OPLL. Mean duration

of preoperative symptom and Nurick score were 7619 months &

2.3(0-5) grades respectively. Radiographically, 81% had C4-5 foraminal

stenosis, 59% had MRI cord signal change at some level in the cervical

cord and 30% had flattening of spinal cord at C4-5. 70% had a 5 levels

laminoplasty & 21% had 4 levels. Bilateral C4-6 foraminotomies were

performed in 66% of patients. Mean operative time and blood lost were

168(90-270) minutes & 188(75-900)ml. 54% patients had laminoplasty

hinge placed on the left side and 46% had it on the right. 4(5.7%) pa-

tients developed unilateral postoperative C5 palsy which did not occur

immediate but within 1-2 weeks of surgery. 3 C5 palsies resolved and

1 had mild residual deltoid weakness at 4.5 years postop. Only the dura-

tion of preoperative myelopathic symptoms was a risk factor for C5

palsy. (P!0.0001) The median preoperative symptom duration for pa-

tients that had a C5 palsy was 36 months. MRI cord signal change

and cord flattening approached but did not achieve significance as risk

factors for C5 palsy. Age, gender, diabetes, cigarette smoking, diagnosis,

pathologies, Nurick grade, hinge location, and multilevel foraminotomies

were not statistically significant.

CONCLUSIONS: Bilateral C4-5 foraminotomy performed at time of

laminoplasty does not eliminate the development of postoperative C5

palsy. While it might reduce the incidence of C5 palsy when compared

to the historical cohorts of laminoplasty patients without foraminotomy,

without a direct comparison with the same surgeon using the same tech-

nique, it is not possible to know. Duration of preoperative symptoms ap-

peared to be a statistical significant risk factor for C5 palsy development.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2007.07.133

113. Same Segment Disease after Cervical Spine Surgery

James Lawrence1, Andrew White, MD2, Alan Hilibrand, MD3; 1Yale

University, New Haven, CT, USA; 2Thomas Jefferson University, New

Haven, CT, USA; 3Thomas Jefferson University, Philadelphia, PA, USA

BACKGROUND CONTEXT: Adjacent segment disease following cervi-

cal arthrodesis has been a motivating factor for the development of cervical

arthroplasty. We define ‘‘same segment disease,’’ as the constellation of

symptoms often associated with radiographic and physical findings that

may develop at the same level of a prior cervical spine procedure. Pseu-

darthrosis, graft and hardware complications, or malalignment can occur

following decompression, arthrodesis, and arthroplasty procedures. The

fate of the ‘‘same segment’’ has not been categorically assessed and com-

pared among different surgical approaches and procedures.

PURPOSE: To introduce the concept of postoperative same segment

disease and categorize/compare its manifestations following different com-

mon cervical spine procedures.

STUDY DESIGN/SETTING: A critical review of the existing peer-

reviewed literature on the outcomes of surgical treatment of cervical spine

disease.

PATIENT SAMPLE: Thirty-four clinical and biomechanical papers were

reviewed for data relevant to the consideration of same segment disease. 14

papers were analyzed concerning same segment disease relating to cervical

arthroplasty procedures, and 21 papers relating to same segment disease

following anterior cervical arthrodesis and other cervical decompressive

procedures were reviewed.

OUTCOME MEASURES: The incidence rates of same segment disease

symptoms and findings (hardware and graft complications, pseudarthrosis,

heterotopic ossification, malalignment, requirement of revision surgery)

were compared for each procedure, as culled from the best known series

in the published literature.

METHODS: The postoperative symptoms and findings that characterize

same segment disease were defined and quanitified for common cervical

procedures, including anterior cervical discectomy and fusion, posterior

cervical fusion, posterior cervical foraminotomy, micro-anterior cervical

discectomy without fusion, and intervertebral cervical disk arthroplasty.

RESULTS: Rates of same segment disease for ACDF, posterior cervical

fusion, posterior foraminotomy, and micro-ACD ranged from 5%–36%.

Symptomatic pseudarthrosis requiring revision after ACDF is relatively

uncommon, ranging from !5%–12% of cases. Hardware complications

following ACDF have been characterized in 22%–36% of cases. Graft ex-

trusion and malalignment have been described in up to 6% of cases follow-

ing anterior cervical fusions. Rates of same segment disease for cervical

arthroplasty procedures vary from 0%–7.3%. Although inflammatory

responses have been described in up to 36% of animals following cervical

arthroplasty, this has not been seen in human trials. Heterotopic ossifica-

tion, fusion around arthroplasty implants, and facet joint degeneration

following arthroplasty have not been well-characterized following cervical

arthroplasty.

CONCLUSIONS: ‘‘Same segment disease’’ (SSD) represents a novel

method of comparison among the various procedures advocated for the

treatment of cervical spondylosis and myo-radiculopathy. SSD rates for

cervical decompressive and arthrodesis procedures appear to be higher

than for cervical arthroplasty. The literature for arthroplasty procedures,

however, represents an incomplete assessment of these phenomena. As

newer cervical procedures become commonplace, an appreciation of same

segment disease and its clinical sequelae will become more critical to well

informed decision making.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2007.07.134

114. Epidemiological Study of Cervical Myelopathy in Community

Toru Yokoyama1, Atsushi Ono1, Takuya Numasawa1, Kanichiro Wada2,

Satoshi Toh3, Kazumasa Ueyama4; 1Hirosaki, Aomori, Japan; 2Hirosaki

University School of Medicine, Hirosaki, Aomori, Japan; 3Hirosaki

University, Hirosaki, Aomori, Japan; 4Hirosaki Memorial Hospital,

Hirosaki, Aomori, Japan

BACKGROUND CONTEXT: Cervical spondylotic myelopathy (CSM)

results from degenerative changes of occurring in the surrounding walls of

the spinal canal. A morbidity of CSM was thought to increase with aging.

However, there were few reports about morbidity of CSM in community.

PURPOSE: The purpose of this epidemiological study was to investigate

a morbidity of symptoms suspected of cervical myelopathy in community.

STUDY DESIGN/SETTING: A prospective cohort study.

PATIENT SAMPLE: Nine hundred and fifty-eight volunteers in a commu-

nity of a neighboring countryside named Iwaki-cho participated in medical

checkup. The volunteers with a history of spinal surgery, rheumatoid ar-

thritis and cerebral disease were excluded. Eight hundred and eighty-one

volunteers, 306 male and 575 female, were enrolled in this study. There

were 83 twenties and thirties, 123 forties, 216 fifties, 260 sixties and

199 seventies and eighties.

OUTCOME MEASURES: The rate of volunteers with suspected mye-

lopathy was evaluated in each generation.