Arthroscopic findings in the initial stages of hip osteoarthritis.

Standard radiographic projections have poor diagnostic ability in detecting early degenerative changes of the hip. Comparison of arthroscopic and radiographic findings is the best method to assess the accuracy of conventional radiography. This study reviewed the records and radiographs of 234 hip arthroscopies. One hundred eighty-six of the patients had normal preoperative radiographs; of these, 60 (32.2%) had evidence of osteoarthritis at arthroscopy. The extent and location of the chondral damage were studied, and both of these parameters were correlated to the radiographic appearance of osteoarthritis. Hips with normal radiographs but arthroscopic osteoarthritis were found to have less damage compared with the radiographically osteoarthritic hip. Hips with normal radiographs also were more likely to have only one side (60%) of the joint damaged, either the acetabulum or femoral head. Conversely, when osteoarthritis was evident radiographically, both sides of the joint were usually involved (75.7%). These patients are often young (average age: 36 years), and women are more likely to be affected than men (71% versus 29%).