Hip bone is easily located through the skin. The iliac crest shows clear marks of the attachment of the three abdominal wall muscles. The ischium forms the lower and back part of the hip bone and is located below the ilium and behind the pubis. The ischium is the strongest of the three regions that form the hip bone. It is divisible into three portions: the body, the superior ramus, and the inferior ramus. The body forms approximately one-third of the acetabulum. The ischium forms a large swelling, the tuberosity of the ischium, also referred to colloquially as the "sit bone". When
Sciatic nerve also innervates muscles. In particular: Pain caused by a compression or irritation of the sciatic nerve by a problem in the lower back is called sciatica. Common causes of sciatica include the following lower back and hip conditions: spinal disc herniation, degenerative disc disease, lumbar spinal stenosis, spondylolisthesis, and piriformis syndrome. Other acute causes of sciatica include coughing, muscular hypertension, and sneezing. Sciatic nerve injury occurs between 0.5% and 2.0% of the time during a hip replacement. Sciatic nerve palsy is a complication of total hip arthroplasty with an incidence of 0.2% to 2.8% of the time, or with an