Metacarpophalangeal Joint Hyperextension and the Treatment of Thumb Basilar Joint Arthritis

Abstract

HUMB BASILAR OR carpometacarpal arthritis is a common and often debilitating condition seen in more than half of women aged over 71 years. 1 It manifests as pain localized to the base of the thumb, as well as global hand dysfunction including weak grip and pinch, and inability to grasp large objects. 2 Eaton and Glickel 3 described the radiographic severity of basilar joint arthritis, and these stages are often used to dictate treatment. Several interventions have been described, including volar ligament reconstruction, trapeziometacarpal arthrodesis, trapeziectomy alone, trapeziectomy with ligament reconstruction, and arthroplasty. 4– 9 Despite this, comparatively little has been described about how to manage the accompanying hyperextension deformity of the metacarpophalangeal (MCP) joint that often exists. Failure to recognize and treat this deformity may lead to suboptimal results. 2 Patients with basilar joint arthritis develop radial adduction and flexion of the first metacarpal with narrowing of the first webspace. The anterior oblique (or volar beak) ligament becomes increasingly attenuated with subsequent dorsoradial subluxation of the metacarpal on the trapezium. 2,10 This leads to a relative