PIP Fracture/Dislocation Treatment Technique: Use of a Hemi-Hamate Resurfacing Arthroplasty.

ABSTRACT

The nature of injury following a PIP fracture dislocation is determined by the direction of force transmission and the position of the joint at the time of impact. Dorsal dislocations with palmar lip fractures are the most frequently encountered and can be classified based on stability. The degree of stability is directly determined by the amount of middle phalangeal palmar lip involvement; the larger the palmar lip fracture, the more unstable the joint becomes. When there is persistent instability or greater than 30 degrees of flexion is required to maintain reduction, treatment must be aimed at reconstituting the cup shaped geometry and buttressing effect of the volar lip of the middle phalanx if stability is to be restored. The use of a hemi-hamate autograft to reconstruct the base of the middle phalanx is a new technique that restores joint congruity and stability while allowing for early motion. This operative technique replaces the damaged palmar lip of the middle phalanx with a size-matched portion of the hamate obtained from its distal dorsal articular surface between the 4th and 5th metacarpals. By restoring both articular congruity and osseous stability the advantage of this procedure is that it allows more immediate rehabilitation with a potential for earlier motion, less stiffness and possibly less post-traumatic arthritis.