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.

Trapezium Fracture Associated with Thumb Carpometacarpal Joint Dislocation: A Report of Three Cases and Literature Review

“…Ramoutar et al [ 3 ] indicated a direct dorsoradial impaction or indirect axial loading as mechanisms for the injury, which is consistent with case 1 in the current study. Kose et al [ 4 ] reported either axial loading on a flexed thumb or commissural shearing forces acting on the first web space as the mechanism of injury, most likely consistent with the mechanism of the injury for cases 2 and 3 in the current study.…”

The Uncommon Trapezium Fracture: A Case Series

“…In most cases, a trapezium fracture also accompanies other injuries such as Rolando's fracture, Bennett's fracture dislocation, scaphoid fracture, and usually dislocation of the first CMC joint. 4,8 The trapezium articulates with four bones: the first metacarpal distally, the scaphoid proximally, and with the trapezoid and second metacarpal medially (►Fig. 6).…”

“…20 There are two main injury mechanisms for thumb CMC dislocations and trapezium fractures. 4,5 The mechanism of injury usually involves either indirect axial overload or direct dorsoradial impaction. 3 An indirect axial overload caused by a fall on the out-stretched hand, resulting in hyperextension and radial deviation of the hand, where the trapezium gets compressed between the base of the first metacarpal and the radial styloid, resulting in a shear fracture through the radial side of the body of the trapezium.…”

“…Isolated trapezium fractures are rare and account for only 1 to 5%of all carpal fractures but is still the third most common carpal fracture. [1][2][3][4][5][6] Twenty percent of these fractures are isolated (with a vertical sagittal split). 7 Often, the fracture also accompanies other injuries such as Rolando's or Bennett's fracture dislocation, scaphoid fracture, and usually a dislocation of the first carpometacarpal (CMC) joint.…”

“…7 Often, the fracture also accompanies other injuries such as Rolando's or Bennett's fracture dislocation, scaphoid fracture, and usually a dislocation of the first carpometacarpal (CMC) joint. 4,8 The fracture of the trapezium can be classified according to the Walker's classification (►Fig. 1); type I: horizontal sagittal split, type IIa: medial distal avulsion, type IIb: medial proximal avulsion, type III: lateral distal avulsion, type IV: vertical sagittal split, type V: communitive.…”