Rupture of the radial collateral ligament of the index metacarpophalangeal joint: diagnosis and surgical treatment.

Purpose: To report the diagnosis and results of 12 surgically treated cases of isolated radial collateral ligament (RCL) tears of the index finger (IF) metacarpophalangeal (MCP) joint.

Methods: Between 1996 and 2002, there were 12 patients who were diagnosed with a tear of the index RCL based on clinical evaluation, had surgical treatment, and were followed up for a minimum of 23 months. All 12 patients sustained complete, full-thickness tears. Three patients chose immediate surgical treatment, and 9 patients failed an initial trial of conservative treatment. Surgical repair was performed because of pain, swelling, tenderness, and instability, and a suture anchor was used in all repairs. Intraoperative findings correlated with preoperative magnetic resonance imaging regarding to the site of the tear and the presence of associated injuries. Range of motion, grip strength, and lateral pinch strength were recorded. Patients were questioned regarding satisfaction with their treatment and with their ability to return to work and/or sporting activities.

Results: The RCL was avulsed more commonly from the metacarpal (7 patients) than from the proximal phalanx (5 patients). There were no midsubstance tears. All patients reported resolution of pain, ability to return to activities of daily living or sporting activities, and satisfaction with treatment. The mean IF MCP joint arc of motion was 80 degrees , with a mean extension and flexion of 0 degrees and 80 degrees , respectively. There was no extensor lag and no laxity to stress in any of the repaired ligaments. The mean grip strength expressed as a percentage of the injured/noninjured side was 111%. The mean lateral pinch expressed as a percentage of the injured/noninjured side was 112%.

Conclusions: On the basis of this study, IF RCL ruptures can be treated successfully with surgical repair.