While many people have slight differences in the length of one leg compared to the other, a significant difference between the two legs can cause problems. Leg length discrepancies can disturb the way a person walks, how his or her spine lines up and strain hip joints.Causes
A number of causes may lead to leg length discrepancy in children. Differences in leg length frequently follow fractures in the lower extremities in children due to over or under stimulation of the growth plates in the broken leg. Leg length discrepancy may also be caused by a congenital abnormality associated with a condition called hemihypertrophy. Or it may result from neuromuscular diseases such as polio and cerebral palsy. Many times, no cause can be identified. A small leg length discrepancy of a quarter of an inch or less is quite common in the general population and of no clinical significance. Larger leg length discrepancies become more significant. The long-term consequences of a short leg may include knee pain, back pain, and abnormal gait or limp.Symptoms
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.Diagnosis
The only way to decipher between anatomical and functional leg length inequalities (you can have both) is by a physical measurement and series of biomechanical tests. It is actually a simple process and gets to the true cause of some runner?s chronic foot, knee, hip and back pain. After the muscles are tested and the legs are measured it may be necessary to get a special X-ray that measures both of your thighs (Femurs) and legs (Tibias). The X-ray is read by a medical radiologist who provides a report of the actual difference down to the micrometer leaving zero room for error. Once the difference in leg length is known, the solution becomes clear.Non Surgical Treatment
After the leg length discrepancy has been identified it can be categorized in as structural or functional and appropriate remedial action can be instigated. This may involve heel lifters or orthotics being used to level up the difference. The treatment of LLD depends on the symptoms being experienced. Where are the femur tibia and fibula?
the body is naturally compensating for the LLD (and the patient is in no discomfort), further rectifying action may cause adverse effects to the biomechanical mechanism of the body causing further injury. In cases of functional asymmetry regular orthotics can be used to correct the geometry of the foot and ground contact. In structural asymmetry cases heel lifts may be used to compensate for the anatomic discrepancy.Surgical Treatment
Surgical lengthening of the shorter extremity (upper or lower) is another treatment option. The bone is lengthened by surgically applying an external fixator to the extremity in the operating room. 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 tension is created by the frame when it is "distracted" by the patient or family member who turns an affixed dial several times daily. The lengthening process begins approximately five to ten days after surgery. The bone may lengthen one millimeter per day, or approximately one inch per month. Lengthening may be slower in adults overall and in a bone that has been previously injured or undergone prior surgery. Bones in patients with potential blood vessel abnormalities (i.e., cigarette smokers) may also lengthen more slowly. The external fixator is worn until the bone is strong enough to support the patient safely, approximately three months per inch of lengthening. This may vary, however, due to factors such as age, health, smoking, participation in rehabilitation, etc. Risks of this procedure include infection at the site of wires and pins, stiffness of the adjacent joints and slight over or under correction of the bone?s length. Lengthening requires regular follow up visits to the physician?s office, meticulous hygiene of the pins and wires, diligent adjustment of the frame several times daily and rehabilitation as prescribed by your physician.