Hip arthroscopy is a relative newcomer to the arthroscopic repertoire, yet even in its current infancy has shown the hip joint in a different light. One poorly understood area is the ligamentum teres, thought by many to do little more than carry a blood vessel in the developing hip. Ligamentum injuries have only rarely been described, though in recent years have been arthroscopically classified We present a large series of ligamentum teres abnormalities treated by hip arthroscopy. Of 925 consecutive hip arthroscopies, 68 patients (73 hips) had either a complete ligamentum tear (Type I), partial ligamentum tear (Type II), or a degenerate ligamentum (Type III). Only 4 patients had a correct diagnosis given prior to hip arthroscopy. Hyperadduction was the commonest cause of Type I tears, though not all tears had a traumatic aetiology. Complete tears have a shorter history and a higher chance of associated intra-articular damage. Partial tears typically have a long history of ill-defined hip pain. The degenerate ligamentum generally presents with the features of underlying osteoarthritis. At three-year review, Type I and II tears improved significantly following hip arthroscopy, Type III abnormalities less so. This paper thus presents the largest series of ligamentum tears to-date reported.
