An isokinetic muscular study was performed on a group of 26 women with primary gonarthrosis before surgery, six months an one year after joint replacement. An evolutive and comparative study of both knees was carried out in order to verify whether the muscular balance was altered in parallel with weaker but retained function of the ischiotibial musculature with an enhanced ischiotibial/quadriceps relation. One year after arthroplasty, extensor strength was not improved, though it was more efficient as revealed by reduced muscular fatigue, while flexor strength and pathological muscular balance were maintained. The flexor/extensor relation was also enhanced in the control knee, making this an early indicator of joint deterioration.

An isokinetic muscular study was performed on a group of 26 women with primary gonarthrosis before surgery, six months an one year after joint replacement. An evolutive and comparative study of both knees was carried out in order to verify whether the muscular balance was altered in parallel with weaker but retained function of the ischiotibial musculature with an enhanced ischiotibial/quadriceps relation. One year after arthroplasty, extensor strength was not improved, though it was more efficient as revealed by reduced muscular fatigue, while flexor strength and pathological muscular balance were maintained. The flexor/extensor relation was also enhanced in the control knee, making this an early indicator of joint deterioration.