The type of surgery depends on the type of problem. Outpatient procedures may be used to alter the growth of the limb. This is often done through small incisions. If an outpatient procedure is done, your child can continue with most regular activities. Other times, surgery may be very involved and require the use of an external device that is attached to the limb with pins and wires. This device may be left on for months to correct the deformity or lengthen the leg. If this type of surgery is required, your child will be making weekly visits to Cincinnati Children's.
LLDs are very common. Sometimes the cause isn?t known. But the known causes of LLD in children include, injury or infection that slows growth of one leg bone. Injury to the growth plate (a soft part of a long bone that allows the bone to grow). Growth plate injury can slow bone growth in that leg. Fracture to a leg bone that causes overgrowth of the bone as it heals. A congenital (present at birth) problem (one whole side of the child?s body may be larger than the other side). Conditions that affect muscles and nerves, such as polio.
The effects vary from patient to patient, depending on the cause of the discrepancy and the magnitude of the difference. Differences of 3 1/2 to 4 percent of the total length of the lower extremity (4 cm or 1 2/3 inches in an average adult), including the thigh, lower leg and foot, may cause noticeable abnormalities while walking and require more effort to walk. Differences between the lengths of the upper extremities cause few problems unless the difference is so great that it becomes difficult to hold objects or perform chores with both hands. You and your physician can decide what is right for you after discussing the causes, treatment options and risks and benefits of limb lengthening, including no treatment at all. Although an LLD may be detected on a screening examination for curvature of the spine (scoliosis), LLD does not cause scoliosis. There is controversy about the effect of LLD on the spine. Some studies indicate that people with an LLD have a greater incidence of low back pain and an increased susceptibility to injuries, but other studies refute this relationship.
Asymmetry is a clue that a LLD is present. The center of gravity will shift to the short limb side and patients will try to compensate, displaying indications such as pelvic tilt, lumbar scoliosis, knee flexion, or unilateral foot pronation. Asking simple questions such as, "Do you favor one leg over the other?" or, "Do you find it uncomfortable to stand?" may also provide some valuable information. Performing a gait analysis will yield some clues as to how the patient compensates during ambulation. Using plantar pressure plates can indicate load pressure differences between the feet. It is helpful if the gait analysis can be video-recorded and played back in slow motion to catch the subtle aspects of movement.
Non Surgical Treatment
Whether or not treatment should be pursued depends on the amount of discrepancy. In general, no treatment (other than a heel life, if desired) should be considered for discrepancies under two centimeters. If the discrepancy measures between two and five centimeters, one might consider a procedure to equalize leg length. Usually, this would involve closure of the growth plate on the long side, thereby allowing the short side to catch up; shortening the long leg; or possibly lengthening the short leg.
The bone is lengthened by surgically applying an external fixation device to the leg. The external fixator, a scaffold-like frame, is connected to the bone with wires, pins, or both. A small crack is made in the bone and the frame creates tension when the patient or family member turns its dial. This is done several times each day. The lengthening process begins approximately five to 10 days after surgery. The bone may lengthen 1 millimeter per day, or approximately 1 inch per month. Lengthening may be slower in a bone that was previously injured. It may also be slower if the leg was operated on before. Bones in patients with potential blood vessel abnormalities, such as cigarette smokers, may also need to be lengthened more slowly. The external fixator is worn until the bone is strong enough to support the patient safely. This usually takes about three months for each inch. Factors such as age, health, smoking and participation in rehabilitation can affect the amount of time needed.