A number of individuals have benefitted from joint replacement surgery. Generally, either a knee or hip joint that has been damaged via degenerative osteoarthritis, or less commonly infection or trauma, is replaced using modern innovative surgical techniques, and specialised joint prostheses.
Complications with joint replacement procedures can include blood clots, infection, loosening, and or dislocation of the joint. A lesser known long term complication is the development of a Leg Length Discrepancy. This occurs when one leg remains either shorter or longer following surgery, which becomes apparent in posture when standing. Your surgeon will make every effort to maintain the leg length that you had before surgery, but there is no guarantee, due to the intricate positioning of the joint prosthetic.
When a leg length discrepancy exists, it is easily observed by the trained eye. Podiatrists trained in this area, review you both standing and lying flat, and are able to identify if a difference exists, and whether it is necessary to treat the difference.
Common symptoms accompanying a leg length difference include:
- Lower back pain when standing for any length of time (functional scoliosis)
- Hip pain
- Scuffing of one foot or tripping regularly
- Bending one knee when standing, to find comfort
- Soreness in the arch or ankle.
If both hips are replaced, can you add height to my body?
Yes, it is possible to increase the leg length on one side, and increase it by the same amount on the other side. But, any gain in height, is about an inch or less. The limiting factor includes the muscles, tendons, and nerves, which have only so much stretch, before there is injury or damage.
Will my leg be longer or shorter after hip replacement surgery?
During hip replacement, the arthritic ball is removed and replaced with a new ball. Since the artificial ball comes in different neck lengths, the surgeon is able to adjust muscle tension, leg length, and ball-socket stability during the hip replacement. These adjustments reflect complex decision-making and trade-offs during surgery. Rarely, because of anatomic constraints, or other patient-specific reasons, slight leg lengthening may occur. If this is totally unacceptable, you should not consider hip replacement surgery. In the overwhelming majority of cases, there is no change in leg length after hip replacement. In most cases where the patient feels a change in leg lengths, that perception will disappear over several months, as the muscle and tissues stretch.
Can leg length be changed during hip replacement surgery?
Yes, if a patient had a leg that was shortened from injuries after a motor vehicle accident, who now needs a new hip. In such cases, it is possible to restore the original leg length during surgery. The decision-making is complex, requires professional judgement, and is specific to each situation. Likewise, if the patient has too long a leg before surgery, it is possible to shorten it during hip replacement, using specific surgical techniques that keep muscle tension within safe limits. Again, the exact steps taken, and the decision making, are specific to each patient.
My leg ended up too long after a hip replacement, can anything be done?
In most cases, with exercise, stretching, and healing over 6 to 12 months, the perception of a leg length difference will disappear on its own. During this time, to avoid a limp and facilitate walking, a shoe lift from the Orthotist, or heel raise from the Podiatrist can help. The reason for waiting, is that the majority of leg length discrepancy after hip replacement, is not a true difference in skeletal lengths. Rather, the discrepancy is from pelvic tilt, tight muscles, altered biomechanics, and even spinal arthritis that can lead to a curvature in the back. With muscles stretching, exercises, and time, such discrepancy will likely resolve in a few months.
If leg length discrepancy is permanent, additional surgery may be an option. Steps must be taken to avoid improper muscle tensioning, and to reduce the risk of creating hip instability and a limp.
How can we know if my leg is truly longer after a hip replacement?
Special X-ray studies can help determine if the perceived difference in leg lengths is really in the bone, or arising from some other source, such as a tilted pelvis, a curvature in the back, or tight muscles. These X-rays involve imaging the entire length of both legs with a measuring ruler, that leaves no doubt about the actual length of each leg, from the top of the pelvis to the ankle. Alternatively, a podiatrist can do the measuring tape technique, measuring the distance between the anterior superior iliac spine, and the medial malleolus.
In situations where the length is below 1 inch, it requires a recommendation of a lift to the shoe, or a heel raise/ wedge. A heel wedge of the same size with the shoe, is attached inside the shoe, to lift the length of the shorter leg, to become equal length with the longer leg. Alternatively, a sole lift orthotic is used to equalise the lengths, if the difference happens to be more than 2 cms. The lift will be made to extend below the shoe. In this case, an extra heel is added to the sole of the particular shoe, after it has been shaped, to be similar to the other shoe. Both shoes will now look exactly the same, except for the extra sole added to the shorter leg. These mechanisms are designed to help the person walk, run, and relieve pains that may be experienced at the lower back. They feel comfortable and well supported.
Your feet mirror your general health . . . cherish them!