Is the preoperative radiograph useful in predicting the outcome of a totalhip replacement?

The preoperative radiographs of 1015 patients undergoing 1163 total hip rep lacements for osteoarthritis were evaluated to determine if a relationship exists between the extent of osteoarthritis and the clinical results of a t otal hip replacement. Preoperative radiographs were graded with respect to the degree of cartilage space loss, direction of cartilage space loss (femo ral head migration), and severity of osteophyte formation. Followup average d 32.1 months (range, 6-93 months). Greater degrees of cartilage space loss correlated with lower hip scores preoperatively but were unrelated to preo perative pain. These patients had statistically less pain at 6 months and 1 year. Patients with superior cartilage space loss before surgery also had statistically less pain at 6 months. However, at 3 years and beyond, pain w as independent of degree of preoperative cartilage space loss, osteophyte f ormation, or femoral head migration. In addition, hip scores at any followu p were independent of the degree of osteoarthritis observed on the preopera tive radiograph. These findings provide statistical support to the concept that greater degrees of joint space loss correlate with better relief of pa in and less severe joint space loss correlates with less relief of pain wit hin the first year after total hip replacement. At 3 years and beyond, hip and pain scores were independent of the degree of preoperative osteoarthrit is.