Gluteal muscle contracture (GMC) is a clinical syndrome caused by degeneration and contracture of the gluteal muscle and its fascial fibers, resulting in functional limitation of the hip joint and its characteristic gait and signs. Since the report of Valderrama1 in 1970, there have been many reports at home and abroad, but the etiology and classification are not yet clear. Typical clinical manifestations of GMC include: external “eight” gait, inability to squat with knees in frog squatting position, limited running and jumping, positive circle sign and cross-legged test, etc. GMC is a group of clinical syndromes caused by a variety of causes and mainly manifested by hip joint dysfunction. The classification of GMC according to the cause and the degree of lesion can help to better understand and guide the treatment of GMC. 1. Injectable GMC has been widely reported in the domestic and international literature. It is mostly seen in countries and regions where there is a habit of intramuscular hip injection. Domestic regional surveys have shown that the prevalence of GMC in children ranges from 1% to 2.49%, with benzyl alcohol as the penicillin solvent being the most dangerous causative factor. Some studies have shown that the younger the age of initiation of intramuscular injection, the higher the chance of incidence. The immune function and anatomical characteristics of infants and children may be closely related to the occurrence of GMC. It is especially noteworthy that the incidence of GMC is very high in patients with combined sciatic nerve injuries, and therefore nerve release and contracture band release procedures should be performed simultaneously and as early as possible. The majority of patients with injectable GMC can be treated well with partial excisional release of the contracture band. In most cases, it is not necessary to expose the sciatic nerve, but in extensive lesions, especially in combination with small external rotators or hip capsule contractures, it is advisable to expose the sciatic nerve first to prevent damage to the nerve. In patients with a plate-like contracture of the gluteal muscle and estimated difficulties in release surgery, an iliac crest dissection and peeling of the external iliac plate can be performed to lower the starting point of the gluteal muscle. The advantage is that it can obtain good surgical results and prevent accidental injury to the sciatic nerve and complication of hip extension weakness after extensive release of the contracture band. 2. The cause of idiopathic GMC is unknown. There is no history of intramuscular injection, no history of trauma, no history of other muscle contractures and no family history of the disease. The age of onset varies, but it may occur after 3 years of age or during adolescence. The symptoms gradually worsen after the onset of the disease, and the lesions are mostly symmetrical and bilateral, with milder lesions, mostly located in the external and inferior gluteus maximus muscle migrating to the iliotibial bundle, with lamellar contracture. Surgical removal of the lamellar contracture can achieve satisfactory results. 3.GMC complicating after congenital hip dislocation mostly occurs in children who are older, have high position of femoral head dislocation, after open repositioning and pelvic osteotomy, and the incidence is 0.4%. Due to the wide range of surgery, heavy tissue damage and susceptibility to fibrous degeneration, the high dislocation of the femoral head is located in the primary acetabulum, as well as the rotation and lengthening of the pelvic osteotomy, the suture of the iliac crest periosteum under tension makes the gluteal muscle relatively lengthened and the muscle tension is significantly increased; in addition, the long-term postoperative external booth plaster braking may aggravate the muscle tension and ischemic state and fibrous degeneration occurs. Secondly, tight hip capsule suture may also cause abduction contracture deformity. Some scholars believe that the symptoms of GMC were neglected in some patients before surgery and became obvious after pelvic lengthening. Preventive measures include adequate preoperative traction, not to close the hip capsule too tightly during surgery, and not to close the iliac crest periosteum in situ if the tension is too high. Since the formation of this type of GMC is mainly related to postoperative hypertonicity and fibrous scarring of the gluteal muscles, we believe that iliac crest dissection and gluteal muscle starting point subluxation surgery is more suitable for this type of patients. 4. Gluteal fascial interval syndrome is rare. It occurs mostly unilaterally. The former is often overlooked due to the presence of systemic complications and delays in diagnosis; the latter can be prevented from causing this complication if it is accompanied by severe pain and timely incision and decompression. The pathological mechanism is the same as that of the extremity fascial interval syndrome, which ultimately results in ischemic necrotic contracture of the gluteal muscle within the interval. However, because the sciatic nerve does not pass directly through the gluteal fascia interval, there are no or mild symptoms of nerve injury. The occurrence of GMC can be avoided by timely incision and decompression to save the still viable muscle tissue, and after surgery, the affected hip should be placed in an inward flexion position and functional exercise should be performed early. GMC symptoms should be released by elective surgery. 5. Infectious GMC usually has a history of hip soft tissue infection. Skin scars formed by drainage or abscess sinus tracts can be seen in the hip and infected area. Deep, widespread infection of the soft tissues of the buttocks may spread to the thigh causing quadriceps contracture. The fibrous scar tissue formed by gluteal fascia and broad fascia infection and muscle necrosis is extensive and tough in a plate-like contracture. Prompt management of gluteal infection, prevention of infection spread and early functional exercise after infection control can help prevent the development of GMC. Contracture release surgery needs to be performed more than 3 months after infection is completely controlled, and if combined with quadriceps contracture should be treated together. 6. Local manifestations of multiple myofascial contractures. The contracture symptoms appear slowly and gradually increase, and GMC symptoms appear when the lesion invades the gluteus fascia. Surgical treatment only improves the local function of the joint and has no effect on the natural progression of the disease, with a high disability rate. There are reports in the literature that some GMCs have a genetic predisposition and may have a family history. It is thought that they may be congenital diseases inherited in different ways under the effect of certain environmental factors. 7. The most common soft tissue tumor of the buttocks in children is ligament-like tumor. Most of the tumors are painless or painless and are easily overlooked. Because the tumor invades the gluteal muscle and its fascia causing dysfunction, it is often seen due to the clinical manifestations of GMC. Therefore, children with unilateral GMC should be on high alert. The main differentiating point is a full hip without sharp hip sign and a mass that infiltrates the gluteal muscle and fascia. Early diagnosis and wide and complete resection of the tumor and its involved tissues including some surrounding healthy tissues is the key to successful surgery. 8.Intertrochanteric fracture of the femur with a 25° posterior tilt of the femoral neck is a deformed connection that causes a cool resemblance to the performance of a gluteus maximus contracture. The two knees cannot come together when squatting, and the affected hip is abducted at least 30° to squat. When the anterior femoral neck tilt is corrected to 10° by osteotomy, the symptoms and signs of GMC disappear. Traditional open release surgery is gradually being eliminated due to large surgical incisions, trauma, relatively slow recovery, relatively high incidence of postoperative complications such as subcutaneous blood and fluid accumulation, and unsightly appearance of the hip. Instead, minimally invasive surgery has been developed in recent years, which can be divided into small incision or arthroscopic release surgery, and is applicable to the majority of GMC patients, especially arthroscopic release using radiofrequency equipment, with less intraoperative bleeding and a significantly lower postoperative complication rate than traditional open surgery. Only a few patients with severe GMC still require open surgery.