Carpometacarpal dislocation of the thumb associated with fracture of the trapezium

Abstract

Carpometacarpal dislocation (CMC) of the thumb associated with fracture of trapezium is an extremely rare injury, with only 12 cases that sustained similar injuries reported in the literature. In this article, another patient with this rare injury was reported, and all previously published cases were extensively reviewed. The presented case and all previously published cases had a longitudinally oriented trapezium fracture, which is naturally unstable and almost always associated with dislocation of the CMC joint. In contrast to previous descriptions, we believe that CMC joint dislocation and trapezium fracture are not two distinct pathologies that occur simultaneously by chance but share cause and consequence.

Fig. 1

Volar (a) and dorsal (b) appearance at presentation

Fig. 2

Anteroposterior (a) and oblique (b) radiographs. White arrow trapezium fracture

Fig. 3

Postreduction radiograph of the carpometacarpal (CMC) joint showing adequate reduction and a congruent joint

Fig. 4

Final hand radiographs 6 months after injury

Fig. 5

Classification of trapezium fractures by Walker et al. [16]. Black lines show the fracture