BACKGROUND: Disorders of the thumb metacarpophalangeal (MCP) joint can lead to significant loss of function and pain. Thumb MCP arthrodesis following traumatic injuries is inadequately described and recent studies have questioned the outcome of this treatment.

PURPOSE: The purpose of this study was to report outcome and disability following thumb MCP joint arthrodesis in the treatment of chronic instability after traumatic injuries.

METHODS: A retrospective review of 26 patients operated on with MCP joint arthrodesis, median follow-up 42 months (8-104months). Subjective outcome was assessed using the disabilities of the Arm, Shoulder, and Hand-questionnaire (DASH). In addition, patient satisfaction, pain, stiffness, and impairment of activities of daily living were assessed on a Visual Analogue Scale (VAS) followed by a question stating whether they would undergo the same procedure again.

RESULTS: Two patients (7.7%) needed re-operation due to nonunion. Four patients (15.4%) needed hardware removal. Median DASH-score was 18 (25-75% range 6-47), with lower DASH scores being better. Scores were significantly worse in gender and age matched individuals (p<0.05). Median VAS for pain was 3.7 (range 0-8). More than 50% of patients reported mild, moderate or severe pain, but all patients reported that they were willing to undergo the same procedure again.

CONCLUSION: Our data suggest, that patients with post-traumatic thumb injuries managed with thumb MCP joint arthrodesis perform worse than gender and age matched individuals. Many lived with pain, but all reported that they were willing to undergo the same procedure again. We suggest that the disability scale by the National Board of Industrial Injuries should be reconsidered for patients operated on with thumb MCP arthrodesis.