Arthroscopic surgery for degenerative rupture of the ligamentum teres femoris.

We performed arthroscopic debridement for degenerative rupture of the ligamentum teres femoris in a patient and obtained good results. A 78-year-old woman suddenly developed intense load-bearing pain from the left lumbar to gluteal region, and giving way, without a definitive cause. At presentation, the range of motion of the left hip joint for external rotation was 0 degrees, showing restricted motion. When passive internal rotation was applied at 90 degrees of flexion, intense pain in the left gluteal region was induced. At the initial radiographic examination, there were no abnormal findings in the left hip joint. However, arthroscopic findings showed degeneration in the articular cartilage and labrum but no tear. In addition, degenerative rupture of the ligamentum teres femoris was observed and it was entrapped in the posterior joint space. Using a bipolar radiofrequency scalpel, the entrapped stump of the ligamentum teres was vaporized and excised. The restriction in external rotation of the hip joint observable even under anesthesia was resolved immediately after surgery. Two years after surgery, the patient had regained her preoperative walking ability with the aid of a T cane, and radiographic examination showed no coxarthrosis changes. This case indicates that coxalgia caused by degenerative rupture of the ligamentum teres femoris is also a good indication for arthroscopic debridement.