Scaphoid pain but no fracture8/31/2023 CT also is useful in assessing bone union 8. CT is useful for staging scaphoid fractures if surgery is considered and when fractures of the carpus are extensive or complex. CT may be insensitive to trabecular injury 5. Reported sensitivities, specificities and negative predictive values for CT have been reported CT to be 89-90%, 85-100%, and 97-98% respectively. CTĬT may be used for diagnosis when plain films are normal because it is readily available and quick 12. Fractures may be associated with overlying heterogenous collections which do not deform with compression by the transducer, representing hematomas 19. Ultrasonography may be used as an adjunctive imaging modality in the detection of acute scaphoid fractures. Sonographic windows commonly obtained include longitudinal and transverse views at the radial border of the wrist, volar wrist just medial to the thenar eminence, and dorsal wrist adjacent to lister's tubercle 18.įocal interruption of the thin echogenic cortex serves as direct sonographic evidence of fracture. With time the proximal part undergoes osteonecrosis, becomes increasingly sclerotic and can "implode" and fragment with secondary osteoarthritic changes 9. This can be on account of the rest of the wrist undergoing demineralization due to immobilization, whereas the proximal portion being bereft of blood supply retains its calcium. If osteonecrosis develops the first sign will be slight sclerosis. Scaphoid fat pad sign: obliteration or lateral displacement of a straight/convex lucent line on the lateral aspect of the scaphoid 11Īssociated scapholunate ligament disruption ( Terry Thomas sign) which can be accentuated with a clenched fist view Soft tissue swelling and lateral displacement of the adjacent fat pads Visualization of the fracture +/- displacement It should, however, be noted that the initial radiograph can miss from 5-20% of fractures in the acute setting 1. It is positionally different from the wrist series. Herbert and Fisher classification of scaphoid fracturesĪ dedicated plain radiographic series investigating the scaphoid exists, consisting of four projections of the scaphoid bone. Mayo classification of scaphoid fractures shot putters or gymnasts) 8.įractures can occur essentially anywhere along the scaphoid, but distribution is not even 16:ĭistal pole (or so-called scaphoid tubercle): 20% Occasionally stress fractures are also encountered although these are less common, and only usually seen in athletes (e.g. The usual mechanism is falling on an outstretched hand, applying an axial load to an extended and pronated wrist in ulnar deviation 7. The scaphoid shift test and axial loading of the thumb may also elicit pain. Pain may be elicited by palpation at the scaphoid tubercle (volar/radial), in the anatomic snuffbox, and just distal to Lister's tubercle. Circumduction of the wrist is often painful 20. The dorsum of the wrist may be edematous. Patients will typically present with pain around the dorsal wrist and/or the anatomical snuffbox after a fall on an outstretched hand. Older patients falling in a similar manner are more likely to sustain a distal radial fracture (usually a Colles fracture). Although they occur essentially at any age, adolescents and young adults are most commonly affected 1. Scaphoid fractures account for 70-80% of all carpal bone fractures 1.
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