Arthroscopic Wafer Procedure Versus Ulnar Shortening Osteotomy as a Surgical Treatment for Idiopathic Ulnar Impaction Syndrome

Abstract

PURPOSE: To compare clinical and radiologic outcomes and complication rates of the arthroscopic wafer procedure (AWP) and ulnar shortening osteotomy (USO) for idiopathic ulnar impaction syndrome (UIS). METHODS: From May 2009 to June 2014, 42 patients who were aged 45 years or older with idiopathic UIS underwent either the AWP or USO under the following identical surgical indications: (1) less than 4 mm of positive ulnar variance, (2) Palmer classification 2C or 2D lesion of the triangular fibrocartilage complex, (3) stable distal radioulnar joint (DRUJ) and/or lunotriquetral joint, and (4) no evidence of osteoarthritis of the DRUJ or ulnocarpal joint. The patient assignment was not randomized. Were used a visual analog scale for ulnar wrist pain; grip strength; range of motion; the Mayo Wrist Score (MWS); and the Disabilities of the Arm, Shoulder and Hand (DASH) score at 3, 6, 12, and 24 months after surgery to compare clinical outcomes. Ulnar variance, cystic changes of the lunate and triquetrum, and DRUJ arthritis on radiographs and operation-related complications were compared. RESULTS: This study evaluated 19 patients after the AWP and 23 patients after USO. At 3 months, the AWP produced significantly better outcomes than USO regarding grip strength (79.6% +/- 14.3% vs 62.7% +/- 12.6%, P < .001), MWS (81.8 +/- 7.9 points vs 71.3 +/- 14.2 points, P = .005), and DASH score (19.4 +/- 8.4 vs 31.5 +/- 14.0, P = .001); clinical outcomes were similar at 6, 12, and 24 months. The complication rates were 34.8% for USO and 10.5% for the AWP; complications included DRUJ arthritis (n = 4), implant irritation (n = 6), and refracture after implant removal (n = 2) in the USO group and secondary surgery (n = 1) and tendinopathy (n = 1) in the AWP group. CONCLUSIONS: The AWP and USO for idiopathic UIS with subtle positive ulnar variance achieved similar clinical and radiologic outcomes at 2 years after surgery. However, compared with USO, the AWP showed lower complication rates and better grip strength, MWS values, and DASH scores at 3 months after surgery. LEVEL OF EVIDENCE: Level III, comparative trial.