To determine the significance of Magnetic Resornance Arthrography (MRA) and arthroscopy for diagnosis and treatment of acetabular labral tears as a cause of chronic hip pain.

Thirty-seven hips with clinical suspicion of labral lesions were examined with MRA between Mar. 1995 and Mar. 1998. Among them, twenty-two patients underwent the diagnostic and operative arthroscopy. Another fifteen patients were observed closely without management.

The mean age was 43 years (18-68 years) and male was twenty-five (68%) . Most common causes was degenerative (10 cases, 27%) and idiopathic (10 cases, 27%) . In MRA, stage IIA (partial tear by Czerny classification) were most common findings (twenty-one portion, 47%) . Including double tears in several patients, most common labral tear was located in the anterosuperior portion ( twenty-three cases, 51%) . Comparing arthroscopic finding, the accuracy of MRA for diagnosis of labral tear was 86.4%. Arthroscopically, we modified the morphological classification of labral tear to radial fibrillated (10 portions) , radial fibrillated + peripheral longitudinal (3) , peripheral longitudinal (4) , complete detachment (5) . All patients except three (86.4%) were improved by the arthroscopic partial labrectomy. In conservative patients, only three (20%) were spontaneously improved.

MRA, and subsequent arthroscopic management appears to be a promising modality for detection and treatment of labral tear in patients with chronic hip pain.