Review of Leg Length Changes After Hip Replacement

Medical errors are a fact of life. Doctors do everything they can to reduce errors whenever possible. In the world of orthopedics leg length discrepancy after total hip replacement (THR) is one of the more common types of error. Dr. Clark and his associates from the University of Iowa Hospitals report on this problem.

Patients who are unhappy with the results of their THR often have a leg length discrepancy. This is an unexpected and uncomfortable result. Sometimes there is pain involved because of nerve damage. Problems can occur with walking and balance. Severe neurologic symptoms are possible.

What can be done to prevent this from happening? Dr. Clark advises orthopedic surgeons to do three things. First assess the patient for leg differences carefully before surgery. Ask the patient if the legs feel equal. Do they use a shoe lift? Ask about the history of any conditions that can have an effect on leg length.

Second, check for muscle tightness and measure for length differences. These two steps must be done before and during the operation. Ways to accurately measure leg length are described. X-rays should be examined for any sign of leg length differences. This baseline will be used during and after the operation for comparison. Assess for spine curvature called scoliosis.

Third, the surgeon must warn the patient that equal leg length is not guaranteed after a THR. Tissue scarring and muscle shortening can make the leg shorter. If the longer leg is being operated on, adding the various parts of the hip implant can make it even longer.

Finally the authors discuss ways the surgeon can treat a leg length difference. Time is the first treatment. Soft tissue relaxation and changes can occur during the first six months after THR. In other words the problem may go away on its own. A shoe lift works for some. Others benefit from physical therapy. In the future improved implants, operative technique, and technology will likely do away with this problem altogether.