Objective:To explore the pathogenesy and therapeutic methods of gluteal muscles and fascia contracture associated with both lower limbs pseudodiscrepancy.Method:From March 1980 to October 2003,73 patients of gluteal muscles and fasica contracture associated with both lower limbs pseudodiscrepancy were analyzed retrospectively.There were 42 males and 31 females,with the average age 12 years old(4~22 years).Unequal leg lenglth was less than 2 cm in 39 cases,between 2 cm to 4 cm in 31 cases,more than 4 cm in 3 cases.The contracture band of gluteus maximus muscles was cut off and released.So did the contracture band of gluteal fascia and tensor fascia lata.A “Z”-shaped lengthening was performed when there was the contracture of gluteus medius muscles and gluteus minimus muscles.The patients had to lie on the bed with flexing of hip joint for 3 days,and then did functional exercises on the ground.Result:All cases were followed up for an average of 39 months.In 70 cases,pseudodiscrepancy was completely corrected in 15~45 days postoperatively,and there was no recurrence.The other 3 cases,who were elder ages,remained 1 cm pseudodiscrepancy in appearance.Conclusion:Pelvic obliquity caused by different seversity of contracture of gluteus medius(minimus)muscles leads to unequal leg length in both side or in one side.The desease can be cured through a “Z”-shaped lengthening operation to gluteus medius(minimus)muscles and suitable functional exercises.