[Radiological changes in the femoral side after cementless total hip arthroplasty]

We investigated radiological and functional changes of the femurs with cementless total hip arthroplasty. Our particular attention was paid to the relationship between the thigh pain and the rate, period of its incidence and the progression of radiological changes. The cases studied consisted of 57 female patients with severe coxarthrosis who were implanted with a SUS316-L macroanchoring type of THP (JIAT). Clinical evaluations, radiographic findings in the femoral side, and osteometric observations were carried out periodically in the period before surgery until five years after surgery. The JOA criterion at the time of the final examination was average 91 points. However, we observed a high degree of bone change in the femur on the radiogram. Of 63 hips, there was 71% cortical bone atrophy, a 43% reduction of cortex thickness, 25% cortical bone hypertrophy, 94% endosteal bone bridging in the stem tip, a 64% linear sclerosis of the neighboring stem, and a 37% enlargement of the medullary cavity. Bone atrophy was manifested soon after surgery, and there was 34% recovery. Further, there was no connection between thigh pain and bone changes. We, therefore, concluded that such bone changes as atrophy would not immediately bring about adverse consequences.