Prospective outcomes of stage III thumb carpometacarpal arthritis treated with arthroscopic hemitrapeziectomy and thermal capsular modification without interposition.

PURPOSE: To prospectively evaluate the subjective and objective results of Eaton stage III thumb carpometacarpal arthritis treated with arthroscopic hemitrapeziectomy and thermal capsular modification without interposition.
METHODS: Twenty-three patients with Eaton stage III thumb carpometacarpal arthritis had arthroscopic hemitrapeziectomy without interposition and were evaluated with regard to grip and pinch strength, digital and wrist motion, Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, analog pain scores, and radiographic findings before surgery, 3 months after surgery, and at a minimum of 4 years after surgery.
RESULTS: At 3 months after surgery, average DASH score improved from 61 to 10, and pain scores decreased from 8.3 to 1.5. Grip and key pinch strength improved 6.8 kg and 1.9 kg, respectively, and wrist and digital motion were unchanged. Proximal migration of the first metacarpal averaged 3 mm, and translation decreased from 30% to 10%. Nineteen of 23 patients were pleased with their overall outcomes. After 3 months, DASH scores, grip and pinch strengths, motion, patient satisfaction, and radiographic subsidence and translation remained unchanged for a minimum of 4 years.
CONCLUSIONS: Arthroscopic hemitrapeziectomy and thermal capsular modification offers patients with Eaton stage III arthritis a minimally invasive alternative that can provide increased function and decreased pain by 3 months after surgery. These results appear to last for a minimum of 4 years and are comparable to those reported for open techniques involving complete trapeziectomy. Substance interposition does not appear to be necessary.