Osteoarthrosis and late growth.

To examine the hypothesis that late growth of bone may occur, pelvic radiographs taken during 1990 to 1992 of patients born between 1901 and 1972 were studied. All radiographs were taken using the same equipment with constant exposure techniques. Films showing osteoarthrosis (obviously decreased joint space) or hip fracture were discarded. The remaining films of 116 women and 100 men divided into 3 age groups (18-39 years old, 40-59 years old, and > 60 years old) were measured. With a millimeter ruler and a circle template, the center and 5 radii of each femoral head, the width of the acetabulum, and the pelvic diameters, the femoral neck, and the height of the superior joint space were determined. Most of the measurements increased significantly with age, including those of the femoral head, the acetabulum, the femoral neck in women, and the pelvic diameters. The increase in superior joint space (the combined heights of the cartilage of the femoral head and acetabulum) with age was not significant, but in men between 50 and 70 years old there were cartilage measurements that were higher than in other age groups, and in women > 80 years of age there were significantly more single high values. The results are discussed against the background that growth of bone and of cartilage can hypothetically cause injuries of the cartilage.