Introduction: Carpometacarpal (CMC) arthroplasty provides well-documented pain relief with preservation of thenar function. Nevertheless, a segment of the population undergoing this procedure will continue to have pain following surgery. The authors hypothesize that unrecognized midcarpal (capitolunate) arthritis is a major contributor to persistent pain after CMC arthroplasty. The prevalence of midcarpal arthritis in patients with basal joint arthritis is unknown. The goal of this study is to establish the radiographic prevalence of midcarpal arthritis in patients with CMC arthritis and/or STT (scaphotrapezotrapezoid) arthritis. Methods: Patients with basal joint arthritis were identified from a billing search using International Statistical Classification of Diseases and Related Health Problems (ICD)-9 code 716.94. Hand radiographs were retrospectively reviewed and graded using the Eaton classification and Sodha classification for CMC arthritis. STT arthritis and midcarpal arthritis were graded using the Sodha classification for arthritis. Results: In all, 896 x-rays were reviewed. The overall prevalence of STT arthritis in this population was 64%. The overall prevalence of midcarpal arthritis in this population was 23.5%. The prevalence of midcarpal arthritis in patients with radiologic evidence of CMC arthritis was 25.4%. The prevalence of severe midcarpal arthritis was 7%. Conclusions: The prevalence of midcarpal arthritis in patients with basal joint arthritis is 24%. The presence of 2 locations of arthritis may explain persistent hand and wrist pain in this population despite CMC arthroplasty. Clinically, this data will allow hand surgeons to better educate patients with basal joint and midcarpal arthritis regarding the possibility of incomplete pain relief following CMC arthroplasty.
