idiopathic contracture of gluteus maximus  a term proposed by gao is a rare condition . it present as typical complain of inability to squat with patient assuming a typical frog leg position . we report a case of idiopathic gluteal muscle contracture in adolescent female presenting with inability to squat , sit cross legged and painless awkward gait . no history of repeated intramuscular injections in the buttocks or signs suggestive of post - polio residual paralysis . our patient belonged to type iii according to gmc classification and underwent surgical release of fibrotic band of gluteal maximus muscle . patient had remarkable recovery with patient able to squat and sit cross - legged within 4 weeks of surgery . gluteal maximus contracture , though rare , present with characteristic clinical symptom and should not be missed . contractures of deltoid or quadriceps are well known , leading to the limitation of shoulder or knee joint movement . idiopathic contracture of gluteus maximus  a term proposed by gao is a rare condition   there are only four case reports from the indian subcontinent [ 2 - 5 ] . a 16-year old female presented to the orthopedics outpatient department with complain of inability to squat , sit cross - legged and painless awkward gait for about last six years . detailed birth history could only reveal that she was delivered through normal vaginal route at home and cried immediately after birth . she was normal at birth but when she started walking at the age of 15 months , there was a waddle . she had difficulty in walking and running since early childhood because of the need to abduct and externally rotate the limb in every step . on examination she had an abnormal gait with lower limb kept in the attitude of external rotation and abduction while taking each step . inspection showed a depressed groove over the skin of the buttock running along the course of the gluteus maximus muscle bilaterally , and no skin puckering was observed there was a typical restriction of movement , so that both hips could not be flexed or extended in the usual saggital plane ( between 30 to 90 ) with the hip in neutral position , adduction was limited and squatting was possible in typical frog leg position ( fig . both hips could be flexed in saggital plane but while attempting more flexion there was external rotation and abduction . however the hip joint could be flexed to 110 in wide abduction ( video 1 ) . hip rotations were full and free . according to gmc ( gluteal muscle contracture ) classification radiographic findings were within normal limit no iliac hyperdense line was seen and fibrosis of postero - inferior fibers of gluteal maximus was seen in mri . preoperative clinical photograph of patient showing typical  frog leg position  on attempted squatting there was no other associated abnormal contracture of deltoid or quadriceps . surgical release of bilateral contracture was planned in two separate identical operations for each side with a gap of one week to reduce the operative trauma . the procedures were done through postero - lateral approach with incision extending over the visible skin groove . the skin and subcutaneous tissues are reflected to expose gluteal aponeurosis at its attachment to iliotibial band . a dense fibrotic band extending from the gluteal fascia into the gluteus maximus muscle in the postero - inferior part of the muscle was found . the hip was progressively flexed in saggital plane intraoperatively to ascertain the effectiveness of release . the patient was hospitalised till stitch removal ( 11th post op day ) and graduated exercise was begun . there was remarkable recovery with patient able to squat and sit cross - legged within 4 weeks of surgery with hip flexion of 120 and hip adduction being 10 ( fig . 2 ) . there was no loss in gained movement till 12 months postoperatively after which the patient was lost to follow up . postoperative photo showing patient being able to squat after bilateral gluteal release deep groove seen on posteromedial aspect of gluteus maximus muscle idiopathic bilateral gluteal muscle contracture is a rare occurrence , though other muscle such as quadriceps and deltoid are involved more frequently . few ethinicities , especially chinese have a relatively high prevalence of gluteal maximus muscle contracture [ 7 , 8 ] . genetic or congenital and post natal , but still disease origin seems to be obscure . in all reported cases of gluteal muscle contracture repeated intramuscular injection is most widely documented . the inflammatory reaction incited by intramuscular injections of antibiotics may play an important role in the quadriceps contracture . though no such history could be elicited in our case , but it can not be ruled out . in our patient gluteus maximus contracture produces a backward pull on the three pronged attachment of iliotibial tract displacing its axis posteriorly in relation to femur . contracted gluteus maximus act as a checkrein decreasing the forward flexion of femur producing the characteristic deformity [ 7 , 10 ] . flexion at hip is grossly restricted in saggital plane and hip could only be flexed while keeping it in abduction and external rotation producing the frog leg position . classification of gluteal muscle contracture   previous studies on gluteal maximus contracture had patients in younger age group at the time of intervention [ 1 , 6 , 8 , 10 ] as compared to our patient ( table 3 ) . age was one important factor which influenced the final result , which suggested that either non operative method or surgery should be carried out as early as possible . but our patient being 16 years old showed remarkable result and was able to sit cross legged and squat within 4 weeks of surgery probably due to rigrous physiotherapy regimen . treatment guidelines have been delineated quite precisely by zhao cg et al . according to the severity of disease . the diagnosis of gmc mainly depends on anamnesis , and typical clinical manifestations ; x - ray and mri studies would not be requisite , but could always help eliminate other osteopathologic changes and make available additional information before surgery . passive stretching and manipulation is of no value in treating the deformity in severe / level iii gluteal muscle contracture . complete surgical release of the fibrotic band is only way to correct the deformity . in our case fibrotic band was along the postero - inferior aspect of gluteus maximus contracture , but gao had reported it to be located in anterior part of the muscle . we did open surgical release of gluteal contracture with on table assessment of release by flexing the hip in saggital plane . arthroscopic gluteal maximus muscle contracture release by radiofrequency energy has been tried recently with encouraging result . idiopathic bilateral gluteal maximus contracture is an uncommon entity , should be managed by operative release of the fibrotic band so as to obtain gratifying results . our patient , though presented late , showed excellent result which points that even late intervention can give good results and should be offered to the patient . it present as typical complain of inability to squat with patient assuming a typical frog leg position . a simple single stage procedure will be able to correct the deformity and will have great impact on patients life
introduction : bilateral gluteus muscle contracture is a rare entity .  idiopathic contracture of gluteus maximus  a term proposed by gao is a rare condition . 
 it present as typical complain of inability to squat with patient assuming a typical frog leg position.case report : we report a case of idiopathic gluteal muscle contracture in adolescent female presenting with inability to squat , sit cross legged and painless awkward gait . 
 the patient could not sit comfortably except in a high chair position . 
 no history of repeated intramuscular injections in the buttocks or signs suggestive of post - polio residual paralysis . 
 all her investigations were within normal limit . 
 our patient belonged to type iii according to gmc classification and underwent surgical release of fibrotic band of gluteal maximus muscle . 
 patient had remarkable recovery with patient able to squat and sit cross - legged within 4 weeks of surgery.conclusion:gluteal maximus contracture , though rare , present with characteristic clinical symptom and should not be missed . 
 our patient though presented late showed excellent result after surgical release .