Metacarpal Extension Osteotomy for Mild Thumb Carpometacarpal Arthritis: Retrospective Long-Term Outcomes

Abstract

Purpose:We report clinical and radiologic outcomes after metacarpal extension osteotomy for mild osteoarthritis of the thumb carpometacarpal joint. Materials and Methods: From 1999 to 2008, 11 patients were diagnosed with mild thumb carpometacarpal arthritis (Eaton stage I, II), and extension osteotomies were performed. Of these, seven patients with at least 6 years follow-up were analyzed retrospectively. Male to female ratio was 2:5, and mean age at time of surgery was 38.9 years old. Symptom onset period was a mean of 11.2 months. Two patients were I, and five patients were II in Eaton stage. Preoperative visual analogue scale (VAS) and disabilities of the arm, shoulder and hand scale (DASH) scores were 3.7 points (3-4 points), and 40.1 points (32-51 points). Radial abduction was 38. . Grip strengths and pinch powers, compared with the normal contralateral side were 82% (64%-90%) and 72% (40%-100%), respectively. Results: The mean follow-up period was 8.5 years, and all patients except one maintained their occupational activity during the followup period. Final VAS and DASH scores were 0.7 points (0-2 points) and 11.7 points (8-16 points), respectively, and were statistically significant. Volar abduction, grip strengths, and pinch power were improved to 45 o (40 o -50 o ), 92.3% (73%-117%), and 94.4% (75%-117%) with statistical significances. In five patients, Eaton stages did not change, and two patients advanced to the next stage (stage I to II in one patient, stage II to III in one patient). Conclusion: Among the various treatment options for mild thumb carpometacarpal arthritis, metacarpal extension osteotomy may be considered as an effective treatment.