Scaphoid Fractures. Mohammed Alasmari. Orthopaedic Surgery Demonstrator Majmaah University

Transcription

1 Scaphoid Fractures Mohammed Alasmari Orthopaedic Surgery Demonstrator Majmaah University 1

2 2 Scaphoid Fractures Introduction Anatomy History Clinical examination Radiographic evaluation Classification Treatment Complications

3 Introduction 3 constitute % of all carpal bone fractures. Second only to the distal radius among fractures of the upper extremity. have an obviously different demographic profile. Unlike distal radius fractures, scaphoid fractures are common among young men.

4 Anatomy An irregular shaped bone,more resembling a twisted peanut than the boat. Scaphoid represents floor of the anatomic snuff box Has five articulating surfaces: radius, capitate, lunate trapezium and trapezoid. 4

5 5 Anatomy Articular cartilage covers 80 %. it articulates with the trapezium and trapezoid in a gliding motion, The articulation with the trapezium forms a base for independent movement of the thumb

6 6 Ant.

7 7 Post.

8 Anatomy Blood Supply 8 Major blood supply comes from the scaphoid branches of the radial artery entering the dorsal ridge at or just distal to waist area and supplying % of the bone including the entire proximal pole - in a retrograde fashion Second group of vessels, arise from palmar & superficial palmar branches of radial artery & enter the distal tubercle, it perfuses distal % of bone, including tuberosity

9 9 Blood Supply There are no anastomoses between the dorsal and palmar vessels Vessels enter thru dorsal ridge in 79 %, distal to waist in 14 %, & proximal to waist in 7 % Fractures across scaphoid may destroy blood supply to its proximal part

10 Gelberman RH, Menon J: The vascularity of the scaphoid bone. J Hand Surg [Am] 1980;5: ) 10

11 11 Mechanism of injury Two different mechanisms 1. Compression injury. 2. Hyperextension bending injury.

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13 13 Diagnosis A strong index of suspicion is the key to early diagnosis The diagnosis should be based on : History Clinical examination Radiographic evaluation

14 14 History Occurs after a fall on an outstretched hand. 90% of the patients recalling that. Usually happens in young adult men Wrist pain and Swelling could be minimal in first 24 hours.

15 15 Clinical Examination Tenderness in the anatomic snuff box. Tenderness to palpation over scaphoid tubercle. Tenderness with axial compression. Tenderness as patient supinates forearm against resistance. Radial & ulnar deviation results in pain on radial side of wrist. Forced dorsiflexion usually elicits significant tenderness.

16 16 Clinical Examination There is usually pain at extremes of motion. Limitation of wrist motion but not dramatically. Any ISOLATED test is inaccurate and inadequate

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18 18 Radiographic Evaluation The best method for determining the presence of a fracture. recommended views: 1. AP and lateral 2. scaphoid view 30 degree wrist extension, 20 degree ulnar deviation pronation view

19 19 Scaphoid view :30 degree wrist extension, 20 degree ulnar deviation

20 20 Radiographic Evaluation Importantly if no fracture is seen it is essential to recommend repeat x-rays in 7-10 days 1. If these repeated films are negative also, then MRI (or bone scan if MRI is unavailable) should be recommended if clinical suspicion persists.

21 21 MRI most sensitive method to diagnose of occult fractures within 24 hours allows immediate identification of ligamentous injuries in addition to assessiing of AVN

22 22 Bone scan Bone scan effective to diagnose occult fractures at 72 hours specificity of 98%, and sensitivity of 100%

23 23 CT less effective than bone scan and MRI to diagnose occult fracture can be used to evaluate location of fracture, size of fragments, extent of collapse, and progression of nonunion or union after surgery

24 Classifications of scaphoid fx 24 A. Location of the fracture : 5 different fracture sites : Proximal third ( proximal pole ).. 25% Middle third ( waist ) most common 65% Distal third..10% Distal articular surface ( osteochondral fx )

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26 26 Classifications of scaphoid fx B. Direction of the fracture : Horizontal Oblique, Transverse, and Vertical Oblique.

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28 28 Classifications of scaphoid fx C. Time since injury : Acute fracture - less than 3 weeks old Delayed union - 4 to 6 months old Nonunion 6 months old - more than

29 Herbert classification of scaphoid fractures. 29

30 30 Prognosis Negative prognostic factors are : ü late diagnosis ü proximal location ü displacement ü angulation ü obliquity of the fracture line ü ü smoking carpal instability

31 31 Treatment Is determined by: Location Degree of displacement Fresh vs old fracture

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33 33 Nonoperative thumb spica cast immobilization indicated. duration of casting depends on location of fracture: distal-waist for 3 months. mid-waist for 4 months. proximal third for 5 months. outcomes scaphoid fractures with <1mm displacement have union rate of 90%

34 34 Operative Unstable fractures Stable fractures Displacement > 1 mm 15 Humpback deformity. Radiolunate angle > 15 (DISI) Intrascaphoid angle of > 35 associated with perilunate dislocation. comminuted fractures. unstable vertical or oblique fractures. to allow decreased time to union,faster return to work/sport, similar total costs compared to casting.

35 35 Complication Nonunions AVN especially of the proximal pole, 13% to 50% of such patients regardless of treatment. Arthritis

36 Thank you 36