Epiphysiodesis is a surgical option designed to slow down the growth of the long leg over a period of months to years. It is only used in growing children. The operation involves a general anaesthetic. Small incisions are made around the knee near the growth plates of the thigh bone and the shin bone. The growth plates are prevented from growing by the use of small screws and plates (?8 - plates?). The screws are buried beneath the skin and are not visible. Stitches are buried beneath the skin and do not need to be removed. The child is normally in hospital for 2-3 days. The child can weight bear immediately and return back to normal activity within a few weeks. Long term follow up is required to monitor the effects of the surgery. The timing of the surgery is based on the amount of growth predicted for the child. Therefore, this procedure can under- and over-correct the difference in leg length. Occasionally the screws have to be removed to allow growth to continue. This procedure can be used on one half of the growth plate to correct deformity in a limb e.g. knock-knees or bow legs. This is known as hemiepiphysiodesis.
There are many causes of leg length discrepancy. Some include, A broken leg bone may lead to a leg length discrepancy if it heals in a shortened position. This is more likely if the bone was broken in many pieces. It also is more likely if skin and muscle tissue around the bone were severely injured and exposed, as in an open fracture. Broken bones in children sometimes grow faster for several years after healing, causing the injured bone to become longer. A break in a child's bone through the growth center near the end of the bone may cause slower growth, resulting in a shorter leg. Bone infections that occur in children while they are growing may cause a significant leg length discrepancy. This is especially true if the infection happens in infancy. Inflammation of joints during growth may cause unequal leg length. One example is juvenile arthritis. Bone diseases may cause leg length discrepancy, as well. Examples are, Neurofibromatosis, Multiple hereditary exostoses, Ollier disease. Other causes include inflammation (arthritis) and neurologic conditions. Sometimes the cause of leg length discrepancy is unknown, particularly in cases involving underdevelopment of the inner or outer side of the leg, or partial overgrowth of one side of the body. These conditions are usually present at birth, but the leg length difference may be too small to be detected. As the child grows, the leg length discrepancy increases and becomes more noticeable. In underdevelopment, one of the two bones between the knee and the ankle is abnormally short. There also may be related foot or knee problems. Hemihypertrophy (one side too big) or hemiatrophy (one side too small) are rare leg length discrepancy conditions. In these conditions, the arm and leg on one side of the body are either longer or shorter than the arm and leg on the other side of the body. There may also be a difference between the two sides of the face. Sometimes no cause can be found. This is known as an "idiopathic" difference.
If your child has one leg that is longer than the other, you may notice that he or she bends one leg. Stands on the toes of the shorter leg. Limps. The shorter leg has to be pushed upward, leading to an exaggerated up and down motion during walking. Tires easily. It takes more energy to walk with a discrepancy.
A qualified musculoskeletal expert will first take a medical history and conduct a physical exam. Other tests may include X-rays, MRI, or CT scan to diagnose the root cause.
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.
how do you measure leg length discrepancy?
Surgeries for LLD are designed to do one of three general things ? shorten the long leg, stop or slow the growth of the longer or more rapidly growing leg, or lengthen the short leg. Stopping the growth of the longer leg is the most commonly utilized of the three approaches and involves an operation known as an epiphysiodesis , in which the growth plate of either the lower femur or upper tibia is visualized in the operating room using fluoroscopy (a type of real-time radiographic imaging) and ablated , which involves drilling into the region several times, such that the tissue is no longer capable of bone growth. Because the epiphyseal growth capabilities cannot be restored following the surgery, proper timing is crucial. Usually the operation is planned for the last 2 to 3 years of growth and has excellent results, with children leaving the hospital within a few days with good mobility. However, it is only appropriate for LLD of under 5cm.