Carpometacarpal Dislocation of the Thumb Associated with Fracture of the Trapezium

Abstract

Dislocation of the first carpometacarpal joint combined with a vertical intra-articular fracture of the trapezium is a rare injury. A case is described treated by open reduction of the trapezial fracture and reconstruction of the first intermetacarpal ligament using a slip of abductor pollicis longus tendon.

First Carpal-Metacarpal Joint Dislocation and Trapezial Fracture Treated With External Fixation in an Adolescent

“…Their patient was treated with open reduction, K-wire of the trapezial fracture, and Brunelli type Abd PL ligament reconstruction and showed stability at the 6-month follow-up. 2 Ours is the first description of external fixation to treat an acute first CMC dislocation. We achieved good reduction of the joint and trapezial fracture using closed methods that were well maintained and confirmed under fluoroscopy.…”

“…We believe this is the third case described of a trapezial fracture in combination with a first CMC dislocation. 2,8 Furthermore, this is the first case of a basilar joint dislocation treated by an external fixator with excellent clinical outcome and joint stability.…”

“…2,3 This intrinsic joint stability makes dislocation of the basilar joint a rare injury with fewer than 40 cases described. 4 -7 The mechanism of injury is thought to be from an axial load on a flexed thumb metacarpal that drives the metacarpal base dorsally over the trapezium, possibly resulting in its fracture.…”

“…4 -7 The mechanism of injury is thought to be from an axial load on a flexed thumb metacarpal that drives the metacarpal base dorsally over the trapezium, possibly resulting in its fracture. 2,8 Moreover, the dorsal ligament supporting the joint is thin and unable to resist this dorsal load accounting for the consistently dorsal direction of dislocation. Others have noted that, in addition to the dorsal ligament disruption, the volar ligament may be stripped subperisoteally from the base of the metacarpal.…”

Total carpometacarpal joint dislocation combined with trapezium fracture, trapezoid dislocation and hamate fracture

“…Concomitant injuries of the trapezium with fracture of the base of the 1st metacarpal or with CMC joint dislocations are hardly ever described -usually in a form of a single case report. Trapezium fractures have been reported in combination with CMC 1 dislocation [3][4][5][6][7], fracture of the base of the 1st metacarpal bone [8][9][10] or multiple CMC joint dislocations [2,11,12]. A specific injury combining all these elements together, along with fracture of the hamate and dislocation of the trapezoid has not been described previously in the literature.…”