1980 年 29 巻 1 号 p. 99-103
The purpose of this work is to study the secondary changes in proximal end of femur following the experimental unstable hip joint. These unstable hip joints could be produced by immobilizing the knee joints of young rats in full extension. They were classified into 4 groups according to the immobilizing period. Group I: 1 week, Group II: 2 weeks, Group III: 3 weeks, Group IV: 4 weeks. Group I grew up to the normal hip joints. Group II and III gradually obtained the concentric hip joints but finally some deformities of femur remained. Those were as follows. 1. Small femoral head and short neck 2. Excessive femoral anteversion at 18 degrees 3. Neck—shaft angle showed Coxa Valga. Group IV progressed to complete dislocation and oftenly formed the secondary acetabulum and showed the severe deformity of frmoral head.