Two findings:
(1) Bennett's fracture-dislocation.
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Although only a small fracture fragment is evident there is also involvement of the articular surface at the base of the 1st metacarpal (MC). The fracture is well shown on both radiographs.
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Involvement of the MC articular surface indicates that this is an unstable injury.
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Note the overlap between the thumb (1st) metacarpal and the trapezium. This represents a carpo-metacarpal joint (CMJ) dislocation.
Comment: even were there to be no obvious joint disruption at the carpo-metacarpal joint (CMJ) the extension of a fracture into the joint renders it unstable due to the precise position of the insertion, and pull, of the tendon of abductor pollicis longus. This important muscle insertion, and its effect when an intra-articular fracture is detected, is well illustrated . . .
See : Accident & Emergency Radiology : A Survival Guide (3rd edition) : Pages 164-165
(2) A bone fragment lies adjacent to the styloid process of the radius.
In this patient this is an additional finding. It might well represent an old injury . . . indeed, it appears well corticated. Its clinical significance will depend on clinical examination of the distal radius. If this precise site is clinically unremarkable, then this finding is simply incidental and unimportant.