Abduction Power of Hip after Chiari Pelvic Osteotomy with Femoral Osteotomies using Cybex

A Chiari pelvic osteotomy was performed in 376 hip joints, and a Chiari with femoral osteotomies was performed in 148 hip joints in our hospital.The abduction power of the hip was measured by Cybex and was analyzed using computer simulation.The results were as follows.1) The abduction power of the hip was decreased temporally after the operation, but gradually increased to the preoperative level in 6 to 9 months.2) In the valgus group, the abduction power was increased in the early period, but in the varus group, there continued a decreased period of abduction power in the long term.3) The isometric torque curve of hip abduction in the healthy young male was decresed with hip abduction.4) The vector direction of the abductor muscles was changed medially with hip abduction by simulation.