the Effect of Minimally Invasive Technique Assisted by Magnetic Resonance Neurography

The goal of this clinical trial is to to compare the therapeutic effect of minimally invasive surgery guided by magnetic resonance neurography(MRN) compared with non-magnetic resonance assisted minimally invasive surgery in patients with moderate to severe gluteal muscle contracture(GMC). The main question it aims to answer are: magnetic resonance neurography can better help optimize the surgical path of minimally invasive surgery in the treatment of gluteal muscle contracture.

Participants will underwent preoperative magnetic resonance examination according to different groups, and then the experimental group designed individualized surgical approach and MRN-assisted minimally invasive release according to the imaging findings. In the control group, preoperative magnetic resonance examination was only used to assist in the diagnosis and evaluation of gluteal muscle contracture, and the magnetic resonance results were not used to assist in the design of surgical approach. In the control group, non-MRN-assisted minimally invasive release was performed. The researchers will compare the intraoperative surgery-related indicators and postoperative hip function scores and complications of patients in different groups to see if magnetic resonance-assisted surgery has a better postoperative effect.

According to the different surgical intervention methods, the cases finally included in the study were divided into minimally invasive surgery group and MRN-guided minimally invasive surgery group according to the randomization method. It is expected that the number of cases finally included in the study in both groups will be 22 cases.

Firstly, the age and sex of the two groups of patients included in the study were recorded respectively, and the moderate and severe classification was carried out according to the Zhao \&#39;s classification system. The experimental group and the control group were examined by pelvic X-ray, magnetic resonance and ultrasound before operation. After improving the relevant preoperative examination and excluding surgical contraindications, the intervention measures of the experimental group were to analyze the relationship between the shape of the contracture zone, the distance between the sciatic nerve and the contracture zone, and the external rotation angle according to the preoperative MRN manifestations of the patients, and to design the individualized surgical approach according to the imaging manifestations. MRN-assisted minimally invasive release ; in the control group, preoperative magnetic resonance imaging was only used to assist in the diagnosis and evaluation of gluteal muscle contracture, and the results of magnetic resonance imaging were not used to assist in the design of surgical approach. In the control group, non-MRN-assisted minimally invasive release was performed. For patients, they all underwent magnetic resonance imaging before surgery, and all underwent minimally invasive surgery. However, the design process of the specific surgical approach is not clear, so it is a single-blind design for patients. All the operations were completed by two senior doctors of our research group. The data of postoperative follow-up were recorded, and the conclusion was drawn by statistical analysis.

Intraoperative research indicators include : incision length, operation duration, intraoperative blood loss, first time to get out of bed, pain score, etc.

Postoperative follow-up study indicators included : subjective and objective functional rating scales ( hip flexion and adduction activity, leg squat, cross-leg test, Ober sign, pain in activity, claudication in walking ), patient appearance satisfaction, complications ( wound infection, fat liquefaction, neurovascular injury, incision hematoma formation, etc. ).

Eligibility Criteria:
Inclusion Criteria：

（1). Meet the clinical and imaging diagnostic criteria of GMC ; (2).According to Zhao \&#39;s classification system, patients with moderate to severe GMC diagnosed by medical history, symptoms and physical examination ; (3).Conservative treatment is ineffective for at least 6 months, and daily life is significantly affected ; (4).willing to be hospitalized and receive minimally invasive surgery ; (5). Can cooperate to complete the follow-up ; (6).Patients or immediate family members signed informed consent ; (7). Age 18-65 years old

Exclusion Criteria:

1. . There is clinical or imaging evidence that there is or may be spinal or lower extremity neurological disease ;
2. . There is evidence of hip dysplasia or subluxation ;
3. .after evaluation of intolerance to surgical anesthesia ;
4. .coagulant dysfunction ;
5. . unable to complete the follow-up for various reasons ;
6. . Patients can not complete the scale assessment for other reasons