Drug injection injury, especially penicillin injection, is the most common cause of sciatic nerve injury, also known as medical sciatic nerve injury, preferably in children, the cause of the injury and the injection site improper direct injury or too large a dose of drugs to stimulate the sciatic nerve; sharp instrument injuries, acetabular fracture, pelvic fracture, and dislocation of the hip joint, especially the posterior dislocation is also a common cause of sciatic nerve injury. 1.Movement: If the injury site is in the sciatic foramen magnum or above the sciatic tuberosity, the posterior femoral muscle group, the anterior, posterior and posterior calf muscle groups and the foot muscles are all paralyzed. If the injury is in the middle and lower part of the femur, because the popliteus muscle branch has been largely issued, only the muscles below the knee are all paralyzed. If the branch is injured, the muscles in the innervation area of the common peroneal nerve and tibial nerve are paralyzed. Sensation: Except for the saphenous nerve innervation area at the medial side of the calf and the inner ankle, the sensation in the area below the knee is lost. 3.Nutrition: There are often severe nutritional changes, and the soles of the feet often have deeper ulcers. History of trauma or injections, paralysis of muscles below the thigh or below the knee; paralysis of muscles in the innervated area of nerve branches. Partial sensory loss in areas below the calf. Electromyography confirms the diagnosis. Treatment Gluteal sciatic nerve injury is one of the most difficult and least efficacious of peripheral nerve injuries. The injury to its segments is closely related to local anatomy. Treatment should be positive, according to the injury, take the appropriate treatment. Drug injection injury should strive for early nerve release surgery, saline repeated rinsing, postoperative hyperbaric oxygen therapy, can effectively promote the regeneration and repair of damaged sciatic nerve, the younger the patient, the earlier the surgery, the better the effect; such as cutting injury and other sharp force injury, should be a one-phase repair, the epiphyseal to the end of the anastomosis, postoperative fixation in the position of hip flexion for 6-8 weeks; such as for the hip dislocation or pelvic fracture caused by the sciatic nerve injury If the injury is caused by hip dislocation or pelvic fracture, the sciatic nerve should be reset and decompressed in the early stage, decompression should be relieved, and the decision of whether or not to explore the nerve should be made according to the recovery situation after observing for 1~3 months; if it is caused by firearm injury, only debridement should be done in the early stage, and then exploration and repair should be performed after the wound is healed for 3~4 weeks. Late functional reconstruction of the foot and ankle can improve limb function. Repair of the nerve is of greater significance in promoting sensory and nutritional recovery and can prevent and treat trophic ulcers. The sciatic nerve is revealed as follows. 1.The exposure of the sciatic nerve in the buttock and upper femur is done in the prone position. (1) Incision: from the posterior superior iliac spine outside the lower 4~5cm diagonally downward and outward, through the femur about 2cm medial roughness in an arc inward to the distal midpoint of the gluteal crease, and then along the posterior femoral median downward incision to the required length. (2) Exposure of the sciatic nerve: incise the gluteal fascia, separate the gluteus maximus muscle up to the greater trochanter of the femur, and then incise the femoral fascia longitudinally to the gluteal crease. Cut off the tendinous fibers of the gluteus maximus muscle attached to the iliotibial bundle and the femur, and turn up the gluteus maximus muscle together with its neurovascularity to reveal the sciatic nerve and the pudendal muscle. If necessary, the pyriformis muscle should be cut to reveal the sciatic nerve in the deep surface of the pyriformis muscle. Part of the sacrum or ilium can be removed with bone biting forceps to reveal the sciatic nerve out of the pelvis. 2.The femoral sciatic nerve is revealed in the prone position. (1) Incision. The incision is made along the posterior midline of the femur, the length of which depends on the need. It may extend from the popliteal fossa to the gluteal crease. (2) Incise the deep fascia along the incision, taking care to protect the posterior femoral cutaneous nerve. (3) Separate along the biceps femoris and semitendinosus and retract to the sides, continuing to the depth. (4) Retract the biceps femoris muscle laterally and the semitendinosus and semimembranosus muscles medially to separate the fat around the nerve and expose the sciatic nerve. When separating the nerve, care should be taken to protect the muscle branch. Prognosis If the injury is partial, the postoperative recovery is acceptable; if the injury is complete, the prognosis is very poor.