The term hip describes the joint between the femur bone in the thigh and pelvis. The top of the femur is called the head and represents the “ball” of the ball and socket hip joint. The “socket” is called the acetabulum, which holds the femoral head. The femoral head rotates in the acetabulum to allow walking and leg positioning. The acetabulum and femoral head are covered in cartilage, which provides for an extremely low friction joint.
When a tremendous force is applied through the femur, it can drive the femoral head into the acetabulum causing a fracture of the acetabulum. These injuries usually result from car accidents or falls from great heights. With acetabulum fractures, the smooth cartilage surface is broken and often uneven. If left alone, this will make for an uneven surface for the femoral head to rotate against causing destruction of the joint and severe arthritis.
Other complications from fractures of the acetabulum are severe internal bleeding, damage to internal organs and nerve injury. When the acetabulum is broken, the sharp bone edges can cut large vessels in the pelvis requiring specialized treatment on arrival to the hospital. The bowel and bladder can also be injured by these same sharp bone edges. Nerve injury is not uncommon with acetabulum fractures. Patients can lose bowel and bladder function, sexual function and muscle function controlling the leg and foot.
Traditional treatment of these injuries involved bed rest and traction applied to the injured leg. This can prevent any further displacement of the fractured bone but does not reposition the bone in the appropriate position. Successful treatment of acetabulum fractures depends on restoring the smooth surface of the hip joint. This is best accomplished with reconstructive surgery.
