Arthroscopy during ulnar shortening for idiopathic ulnar impaction syndrome

Arthroscopy during ulnar shortening osteotomy for ulnar impaction syndrome is subject to debate regarding its clinical usefulness. The purposes of this study were to analyze the arthroscopic findings in patients who underwent ulnar shortening osteotomy and to assess the role of arthroscopic evaluation during osteotomy. Medical records and arthroscopic findings of 50 consecutive patients who had been diagnosed with idiopathic ulnar impaction syndrome were retrospectively evaluated. Pathologic changes of the articular disk of the triangular fibrocartilage complex (TFCC), chondromalacia of the lunate and triquetrum, and tears of the lunotriquetral interosseous ligament (LTIL) were evaluated during arthroscopy. Palmer’s classification was used to classify the TFCC lesions. Perforation of the TFCC was observed in 20 patients, and central tears were observed in 10. Thirty-eight patients exhibited chondromalacia of the lunate, including 4 unstable cartilage flaps. Partial tears of the LTIL were detected in 24 patients, including 9 unstable flap tears. In 21 (42%) of 50 patients, arthroscopic findings were not appropriate to define the disease stage with Palmer’s original description. Eight wrists exhibited tears or perforations of the TFCC without evidence of chondromalacia. Seven patients had an LTIL tear without perforation of the TFCC. Lunotriquetral interosseous ligament tears without lunate chondromalacia were found in 7 patients. Arthroscopic debridement was performed in 23 patients based on the clinical judgment that the procedure would help alleviate symptoms postoperatively. Arthroscopy during ulnar shortening osteotomy addresses intra-articular pathologies and may be helpful for symptom improvement.