Thumb by metacarpal extension osteotomy: rationale and efficacy for Eaton Stage I disease

This article describes the rationale and results of a "biomechanical" strategy to restore trapeziometacarpal (TM) stability when symptomatic Eaton Stage I disease exists. Though the author has performed TM arthroscopy, synovectomy, and capsular shrinkage for such cases in 10 patients, the author has been dissatisfied with the outcomes, particularly pain relief. The author currently relies exclusively on extension osteotomy as treatment for this subset of patients. Thumb metacarpal extension osteotomy remains an effective treatment alternative for the hypermobile TM joint consistent with Eaton Stage I disease. This procedure alters forces, shifts load away from the volar compartment, and further engages the dorsoradial ligament. Clinical outcomes are favorable, and no bridges are burned should arthritic changes develop in the future.