Does proximal migration of the first metacarpal correlate with remaining pain after trapeziectomy?

Proximal migration of the thumb metacarpal has been suggested as a possible cause of remaining pain after trapeziectomy for trapeziometacarpal joint osteoarthritis. The aim of this study was to investigate if proximal migration after trapeziectomy is associated with a poorer long-term outcome in terms of pain and objective physical variables. We retrospectively examined 91 thumbs in 65 patients after a mean of 10 years following trapeziectomy with or without ligament reconstruction and tendon interposition. Proximal migration of the thumb metacarpal was measured on plain lateral radiographs of the thumb and correlated to visual analogue pain scale (VAS), thumb range of motion and strength. Most thumbs had a severe proximal migration of the first metacarpal, the mean scaphoid metacarpal distance was 2.7 mm. Most patients reported no or little pain, median VAS was 0 at rest and 1 after load. There were no differences in reported VAS pain at rest or after load between patients with severe (<2 mm scaphoid metacarpal joint space) or less severe (≥2 mm metacarpal joint space) proximal migration. Patients that reported more pain (VAS >2) did not exhibit more migration than patients reporting less or no pain. Thumbs with severe migration had weaker key pinch (3.4 vs. 4.6 kg, p = 0.008) and grip strength (15 vs. 21 kg p = 0.002). We conclude that proximal migration most likely does not cause residual or recurrent pain after trapeziectomy.