Purpose: Radial collateral ligament (RCL) injuries of the thumb metacarpophalangeal (MCP) joint are much less common than ulnar collateral ligament injuries. Cast or splint immobilization is recommended for treating grade I and grade II tears; however, there is no consensus for treating grade III (complete) tears of the RCL. The purpose of this study was to assess the results of repair of acute grade III tears of the RCL and evaluate the efficacy of late reconstruction for chronic instability.
Methods: From 1986 to 2001 there were 26 patients (16 in the repair group, 10 in the reconstruction group) who were reviewed retrospectively and examined clinically after either repair or reconstruction of the RCL of the thumb. The repair group had surgery at a mean of 2.5 weeks after injury and was evaluated at a mean follow-up time of 4.6 years. The reconstruction group had surgery at a mean of 6.8 months after injury and was evaluated at a mean follow-up time of 5.0 years.
Results: At an average follow-up of 59 months, there were no statistically significant differences in MCP or interphalangeal joint motion, grip or pinch strength, or MCP joint stability between the 2 groups. Based on a newly developed grading system there were 12 excellent and 3 good results in the repair group and 8 excellent and 2 good results in the reconstruction group. Overall satisfaction was excellent for both groups.
Conclusions: We recommend the repair of acute grade III RCL injuries and reconstruction of chronic grade III RCL tears of the thumb MCP joint to prevent the development of a painful unstable thumb and possibly to prevent the development of MCP joint arthritis.
Type of study/level of evidence: Therapeutic, Level IV.