Download - Fractures and dislocations of the carpus
![Page 1: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/1.jpg)
Fractures and dislocations of the
carpusBy Gatobu
6A
![Page 2: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/2.jpg)
Scope
• Introduction• Anatomy• Imaging of carpal bones• Lunate fractures/lunate dislocation• Perilunate dislocation
![Page 3: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/3.jpg)
Introduction
• Carpus is a complex unit of bony articulations that transfers the forces of the hand to the supporting forearm and upper extremity• Allows wide range of motion in 2 planes• Carpal bones are 8 in number arranged in 2 rows• Main motions
• Extension• Flexion• Radial and ulnar deviation
• The primary axis of motion resides within the head of carpitate.
![Page 4: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/4.jpg)
General, surgical and applied anatomy• Bones and joints• Composed of 8 bones in 2 rows• The 8 bones are influenced by
• Shape of distal radius• The distal ulnar• Triangular fibrocartilage complex
![Page 5: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/5.jpg)
Anatomy of the Wrist
• Carpal bones tightly linked by capsular and interosseous ligaments.• Capsular (extrinsic) ligaments originate from the radius and insert
onto the carpus.• Interosseous (intrinsic) ligaments traverse the carpal bones.• The lunate is the key to carpal stability.
![Page 6: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/6.jpg)
Extrinsic ligaments
Extrinsic ligaments link the carpal bones to the radius, ulna, and metacarpals.
![Page 7: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/7.jpg)
Intrinsic ligaments
The intra-articular intrinsic ligaments connect adjacent carpal bones.
![Page 8: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/8.jpg)
Lunate
• Connected to both scaphoid and triquetrum by strong interosseous ligaments.
• Injury to the scapholunate or lunotriquetral ligaments leads to asynchronous motion of the lunate and leads to dissociative carpal instability.
![Page 9: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/9.jpg)
Intercarpal Ligaments
•Injury to these ligaments leads to abnormal motion between the two rows, and non-dissociative wrist instability patterns.
![Page 10: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/10.jpg)
Neurovascular anatomy
Circulation of the wrist is obtained through the radial, ulnar, and anterior interosseous arteries and the deep palmar arch
![Page 11: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/11.jpg)
Neurovascular anatomy
• The scaphoid, capitate, and about 20% of all lunates are supplied by a single vessel and thus are at risk for avascular necrosis.• The trapezium, triquetrum, pisiform, and 80% of lunates receive
nutrient arteries through two nonarticular surfaces and have consistent intraosseous anastomoses. AVN is therefore rare.• The trapezoid and hamate lack an intraosseous anastomosis and,
after fracture, can have avascular fragments.
![Page 12: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/12.jpg)
Mechanism of injury
• Most common is an axial compression force applied with the wrist in hyperextension
• Most common injury is a fall on the outstretched hand• Other mechanisms• Palmer flexion,twisting injuries
![Page 13: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/13.jpg)
Mechanism of injury
• High energy forces• Results in carpal bone fractures or ligamentous disruption of both extrinsic
and extrinsic ligaments and perilunate dislocation
• Low energy forces results in minor injuries such as sprains
![Page 14: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/14.jpg)
Imaging
• Plain radiographs: multiple views necessary:• Anteroposterior• Lateral • Oblique• Clenched-fist AP• Radial and ulnar deviation
![Page 15: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/15.jpg)
Imaging
Gilula's lines. A. AP views show three smooth Gilula arcs in a normal wrist. These arcs outline proximal and distal surfaces of the proximal carpal row and the proximal cortical margins of capitate and hamate. B. Arc I is broken, which indicates an abnormal lunotriquetral joint due to a perilunate dislocation. .
![Page 16: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/16.jpg)
Imaging
• Standard scaphoid views detect most carpal injuries• PA x-ray with wrist neutral and in ulnar deviation• elongates scaphoid to better visualize
• MRI scans are useful in detecting occult fractures, AVN of the carpal bones, and ligamentous injuries.• Perilunate dislocations are easily missed if the continuity of Gilula's
line is not assessed.
![Page 17: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/17.jpg)
General Principles of Treatment
• Carefully evaluate x-rays for subtle fractures and/or evidence of carpal instability.
• Reduce and immobilize scaphoid fractures or perilunate injuries pending definitive treatment.
• Diagnose and appropriately treat ligament and bony injuries.
![Page 18: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/18.jpg)
Lunate fractures
• Rare• <1% of all carpal fractures• Isolated fractures of lunate often missed
![Page 19: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/19.jpg)
Lunate anatomy
• Sits like a keystone in the proximal row• Well protected in concavity of the lunate fossa of the radius• Vascular supply-proximal carpal arcade dorsally,palmarly• 7-26% of lunates have single volar or dorsal blood supply
![Page 20: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/20.jpg)
Mechanism of injury
• Hyperextension injury• Others:• repetitive stresses of the wrist• Strenuous push • Avulsion of the dorsal pole( S-L tension)
![Page 21: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/21.jpg)
Classification of lunate fractures
• Acute fractures are classified in 5 groups:• Frontal fracture of palmer pole• Osteochondral fractures of the proximal articular surface• Frontal fracture of the dorsal pole • Transverse fracture of the body• Trans articular fracture of the body
![Page 22: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/22.jpg)
Imaging
• Plain radiographs• Technetium 99m bone scan• CT scan• Arthroscopic exam
![Page 23: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/23.jpg)
Lunate fractures
• MRI
![Page 24: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/24.jpg)
Management of lunate fractures
• Undisplaced-cast immobilization for 4wks• ORIF• Displaced fractures• Associated carpal instability• Non-union
![Page 25: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/25.jpg)
Perilunate dislocation
• Triquetral and scaphoid malrotation• Result of a fall on an outstretched, hyperextended hand• Relatively rare • Occurs when the lunate maintains normal position with respect to
the distal radius while all other carpal bones are dislocated posteriorly
![Page 26: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/26.jpg)
Perilunate dislocation
• Very commonly associated with a scaphoid waist fracture • Sometimes ulnar styloid as well
• Lunate appears triangular in shape on PA view• Lunate rotates forward slightly on lateral view• In lateral view, all other carpal bones are dislocated posterior with
respect to lunate
![Page 27: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/27.jpg)
Perilunate dislocation
![Page 28: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/28.jpg)
Perilunate dislocation
• Represents 2nd of the 4 stages of ligamentous injury around lunate bone resulting from forced hyperextension• They are referred to as lesser arc injuries• The 4 stages of injury are:• Scapholunate dissociation(stage I)• Perilunate dislocation(II)• Midcarpal dislocation(III)• Lunate dislocation(IV)
• With increasing hyperextension perilunate dislocation may become a lunate dislocation
![Page 29: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/29.jpg)
Mechanism of Injury
• Load applied to hand forcing the wrist into extension and ulnar deviation• Severe ligament injury necessary to tear the distal row
from the lunate to produce perilunate dislocation
![Page 30: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/30.jpg)
Physical Exam
• Dorsal displacement of the carpus may be seen• Significant swelling common• Evaluate for compartment syndrome
• If lunate is dislocated, median nerve symptoms may be present
![Page 31: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/31.jpg)
Imaging
![Page 32: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/32.jpg)
Imaging
• Note lack of “colinearity” among the radius, lunate, and capitate on the lateral x-ray.
![Page 33: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/33.jpg)
Imaging
• Note loss of normal carpal “arcs” and abnormal widening of the scapholunate interval.
• Look for associated fractures “trans-scaphoid” injuries
![Page 34: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/34.jpg)
X-ray usually Obvious
![Page 35: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/35.jpg)
X-ray may be subtle
![Page 36: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/36.jpg)
Initial Treatment
• Closed reduction is performed with adequate sedation.
• Early surgical reconstruction if swelling allows.
• Immediate surgery needed if there are signs of median nerve compromise.
• Delayed reconstruction if early intervention is not necessary.
![Page 37: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/37.jpg)
Technique of Closed Reduction
• Longitudinal traction for 5 -10 minutes• For dorsal perilunate injuries: apply dorsal directed pressure to the
lunate volarly while a reduction maneuver is applied to the hand and distal carpal row• Palmar flexion then reduces the capitate into the concavity of the
lunate.
![Page 38: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/38.jpg)
Closed Reduction and Pinning
• Poor results with closed reduction and pinning alone
• Very difficult to reduce adequately• wrist needs to be ulnarly deviated to correct
scaphoid flexion• radial deviation needed to close S-L gap
![Page 39: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/39.jpg)
ORIF with volar and dorsal approaches Procedure of Choice
![Page 40: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/40.jpg)
Dorsal Approach
Repair S-L ligament
![Page 41: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/41.jpg)
Volar Approach
![Page 42: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/42.jpg)
Reduce lunate first- may need to temporary pin to radius
![Page 43: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/43.jpg)
Pin Carpus: S-L, L-T and mid-carpal joints
![Page 44: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/44.jpg)
Trans-scaphoid Perilunate Injuries
• Require reduction and fixation of the fractured scaphoid.• Most of these injuries best treated • ORIF with volar and dorsal approaches • repair of injured structures.
• Open repair supplemented by pin and screw fixation.
![Page 45: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/45.jpg)
Fix scaphoid first: dorsal approach
![Page 46: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/46.jpg)
Pin L-T and Mid-carpal joints
![Page 47: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/47.jpg)
Make sure Radius-Lunate-
Capitate are colinear and S-L
angle restored
![Page 48: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/48.jpg)
Perilunate Injuries Conclusion• Perilunate fracture dislocations are high-energy
injuries• Must recognize different injury patterns• transcaphoid• pure ligamentous• trans radial-styloid
• Early open and anatomic fixation with volar and dorsal approaches provides the best chance at a reasonable functional result
![Page 49: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/49.jpg)
Perilunate dislocation conclusion
• Median nerve dysfunction- 16% of the patients• 16-25% of perilunate dislocations are missed initially
![Page 50: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/50.jpg)
Lunate dislocation
• Most severe of carpal instabilities
Most frequently dislocated carpal bone
• Most commonly associated with a trans-scaphoid fracture
• Involves all the intercarpal joints and disruption of most of the major carpal ligaments
• Produces volar dislocation and forward rotation of lunate Concave distal surface of lunate comes to face anteriorly
![Page 51: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/51.jpg)
Lunate dislocation
• Capitate drops into space vacated by lunate • Results in dislocation of other carpal bones
• Capitate and all other carpal bones lie posterior to lunate on lateral radiograph
• Triangular appearance of lunate on frontal projection (piece of pie sign)• Spilled tea cup sign (lateral view)
![Page 52: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/52.jpg)
Lunate dislocation
![Page 53: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/53.jpg)
Lunate dislocation
![Page 54: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/54.jpg)
Dislocated Lunate
s/s• tenderness•Swelling •ROM painful & limited•May compress median nerve
![Page 55: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/55.jpg)
Lunate dislocation
• Dislocation usually occurs in two steps – 1st the ligaments are torn and then the bone dislocates• + Murphy’s sign
Murphy’s Sign – pt makes a fist. • Indication – lunate dislocation
![Page 56: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/56.jpg)
Lunate dislocation-imaging
![Page 57: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/57.jpg)
comparison
![Page 58: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/58.jpg)
Other imaging modalities
• CT scan• MRI
![Page 59: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/59.jpg)
Treatment
• Closed reduction at A/E• ORIF
![Page 60: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/60.jpg)
Complications
• Wrist arthritis• Persistent pain• Joint instability• Recovery takes at least 6months
![Page 61: Fractures and dislocations of the carpus](https://reader036.vdocument.in/reader036/viewer/2022062500/5681502b550346895dbe1c3c/html5/thumbnails/61.jpg)
Thank you