Many children have one leg that is marginally longer than the other. In most cases, the difference is present at birth but may be too slight to be detected. More significant leg length differences (more than 2 cm) often become obvious as your child grows and begins to crawl and walk. We don?t always know what causes these discrepancies. A significant discrepancy can lead to more serious problems including arthritis and difficulty walking. However, with appropriate treatment, most children with this condition can participate in regular activities. Treatment options include heel lifts and, in more severe cases, surgery to either lengthen or shorten a leg.
Leg discrepancy can develop from a medical issue in any portion of the femur or tibia. One leg may lengthen, but leg shortening is much more common. Factors that can cause leg length discrepancy include inherited growth deficiencies. Infections. A bone infection can cause delayed growth in the affected limb. Injury. If your child breaks a leg, it may be shorter once it heals. This is most likely to happen if the fracture or break was complicated, an open fracture, or an injury that affected the growth plate near the end of the bone. Alternatively, a break can cause bones to grow faster after healing, making a leg longer. Tumors. Legg-Calve-Perthes disease. This is a condition that affects the ball (femoral head) of the hip joint. The femoral head may be friable and damage easily, sometimes leading to shortening of the thigh bone. Hemihypertrophy. In children with this condition, one side of the body grows more quickly than the other. Vascular malformations. These are abnormal clusters of veins and arteries that can form close to the bone and stimulate growth. Juvenile arthritis. Inflammation from arthritis can stimulate growth in the affected leg and cause discrepancy.
The effects of a short leg depend upon the individual and the extent of discrepancy. The most common manifestation if a lateral deviation of the lumbar spine toward the short side with compensatory curves up the spine that can extend into the neck and even impacts the TMJ. Studies have shown that anterior and posterior curve abnormalities also can result.
The doctor carefully examines the child. He or she checks to be sure the legs are actually different lengths. This is because problems with the hip (such as a loose joint) or back (scoliosis) can make the child appear to have one shorter leg, even though the legs are the same length. An X-ray of the child?s legs is taken. During the X-ray, a long ruler is put in the image so an accurate measurement of each leg bone can be taken. If an underlying cause of the discrepancy is suspected, tests are done to rule it out.
Non Surgical Treatment
The non-surgical intervention is mainly usedfor the functional and environmental types of leg length discrepancies. It is also applied to the mild category of limb length inequality. Non-surgical intervention consists of stretching the muscles of the lower extremity. This is individually different, whereby the M. Tensor Fascia latae, the adductors, the hamstring muscles, M. piriformis and M. Iliopsoas are stretched. In this non-surgical intervention belongs also the use of shoe lifts. These shoe lifts consists of either a shoe insert (up to 10-20mm of correction), or building up the sole of the shoe on the shorter leg (up to 30-60mm of correction). This lift therapy should be implemented gradually in small increments. Several studies have examined the treatment of low back pain patients with LLD with shoe lifts. Gofton obtained good results: the patients experienced major or complete pain relief that lasted upon follow-up ranging from 3 to 11 years. Helliwell also observed patients whereby 44% experienced complete pain relief, and 45% had moderate or substantial pain relief. Friberg found that 157 (of 211) patients with LBP, treated with shoe lifts, were symprom-free after a mean follow-up of 18 months.
In growing children, legs can be made equal or nearly equal in length with a relatively simple surgical procedure. This procedure slows down the growth of the longer leg at one or two growth sites. Your physician can tell you how much equalization can be gained by this procedure. The procedure is performed under X-ray control through very small incisions in the knee area. This procedure will not cause an immediate correction in length. Instead, the limb length discrepancy will gradually decrease as the opposite extremity continues to grow and "catch up." Timing of the procedure is critical. The goal is to reach equal leg length by the time growth normally ends. This is usually in the mid-to-late teenage years. Disadvantages of this option include the possibility of slight over-correction or under-correction of the limb length discrepancy. In addition, the patient's adult height will be less than if the shorter leg had been lengthened. Correction of significant limb length discrepancy by this method may make a patient's body look slightly disproportionate because of the shorter leg. In some cases the longer leg can be shortened, but a major shortening may weaken the muscles of the leg. In the thighbone (femur), a maximum of 3 inches can be shortened. In the shinbone, a maximum of 2 inches can be shortened.