[Basic study of cementless hip prosthesis design--analysis of the proximal femur in Japanese patients with osteoarthritis of the hip].

By CT scan, the author analyzed morphologically the proximal medullary canal of the femur in 52 cases of osteoarthritis of the hip. The purpose is to determine the stem shape of an artificial hip joint suitable for Japanese patients. The results were as follows: 1) The femoral head diameter indicated positive correlation with the height, the femoral length, the femoral shaft transverse diameter, and the medullary canal diameter. The proportionality of the femur was found in Japanese patients with osteoarthritis. 2) The femoral head offset indicated no correlation with any results obtained by various measurement. 3) The medullary canal diameter of the diaphysial portion as well as the ratio of the medullary canal to the femur increased with age. 4) The taper angle*, 3.8 degree on the average was positively correlated only with the medullary canal diameter. *"Taper angle" indicates the degree of tapering of the medullary canal.