A new radiographic evaluation of primary osteoarthritis.

Two thousand five hip radiographs, both AP and lateral, were evaluated for osteoarthritis. We excluded all cases of traumatic osteoarthritis, rheumatoid arthritis, avascular necrosis, and congenital deformities. This left 1578 hips in 1309 patients, which were sub-divided into three categories: medial osteoarthritis (405 hips, 20% of which were bilateral, 68% women, 32% men); superior lateral osteoarthritis (934 hips, 19% of which were bilateral, 49% men, 51% women); and global osteoarthritis (239 hips, 23% bilateral, 53% men, 47% women). These categories may have significance in operative technique and survival of acetabular cups after total hip arthroplasty.