Nerve Entrapment Syndromes : Multiple peripheral nerves may be entrapped around the hip and may mimic hip pain.
The lateral femoral cutaneous nerve (meralgia parastheticum) is usually entrapped with scar tissue from previous abdominal surgeries or tight clothing, obesity has also been described as a cause. A positive Tinel’s sign is usually found just infero-medial to the anterior superior iliac spine. Anaesthesia/paraesthesia of the anterolateral aspect of the thigh is commonly described by the patient.
The Sciatic nerve may be entrapped by the piriformis as it runs around the muscle. Unusual anatomic arrangement of the Sciatic nerve, which occurs in a significant percentage of the population may predispose patients to this condition. Pain usually radiates into the buttock and posterior thigh. A mass around the piriformis muscle may be palpable and pain is reproduced with internal rotation of the extended hip.
Ilioinguinal nerve entrapment may be caused by obesity, pregnancy or surgical scarring. Patients complain of pain radiating into the groin and perineum, there may be a positive Tinel’s sign close to the external inguinal ring and hyperextension of the hip may reproduce the pain.
Obturator nerve compression causes medial thigh pain and/or parasthesiae. Pelvic scarring or mass lesions on the usual causes. Pain may be exacerbated by external rotation and adduction in a standing position and there may be associated adductor muscle weakness.
Management of all of these conditions usually involves decompression of the affected nerve.
