Overview
Small or mild length leg discrepancies (LLD), i.e., below 3.0 cm, have been considered as enough to cause orthopaedic changes such as lumbar pain, stress fractures and osteoarthritis on lower limbs (LLLL) joints. In addition to the classification by its magnitude, discrepancies can also be categorized according to etiology, being structural when a difference is noted between bone structures' length or functional as a result of mechanical changes on the lower limb, and are found in 65% - 70% of the healthy population.
Causes
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.
Symptoms
Faulty feet and ankle structure profoundly affect leg length and pelvic positioning. The most common asymmetrical foot position is the pronated foot. Sensory receptors embedded on the bottom of the foot alert the brain to the slightest weight shift. Since the brain is always trying to maintain pelvic balance, when presented with a long left leg, it attempts to adapt to the altered weight shift by dropping the left medial arch (shortening the long leg) and supinating the right arch to lengthen the short leg.1 Left unchecked, excessive foot pronation will internally rotate the left lower extremity, causing excessive strain to the lateral meniscus and medial collateral knee ligaments. Conversely, excessive supination tends to externally rotate the leg and thigh, creating opposite knee, hip and pelvic distortions.
Diagnosis
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
Treatment for an LLD depends on the amount of difference and the cause, if known. The doctor will discuss treatment options carefully with you and your child before any decisions are made. It is important to note that treatment is planned with the child?s final height and leg lengths in mind, not the current leg lengths. Treatment is generally not needed if the child?s final LLD is predicted to be 2 centimeters or less at full height. However, the child should return to an orthopaedic doctor by age 10 for re-evaluation. Treatment is often recommended for LLDs predicted to be more than 2 centimeters at full height. If treatment is done, it usually doesn?t begin until the child starts walking. Possible treatment options include, A ?lift? in one shoe to level the child?s hips. This is often the only treatment needed for small discrepancies.
leg length discrepancy exercises
Surgical Treatment
Surgery to shorten the longer leg. This is less involved than lengthening the shorter leg. Shortening may be done in one of two ways. Closing the growth plate of the long leg 2-3 years before growth ends (around age 11-13), letting the short leg catch up. This procedure is called an epiphysiodesis. Taking some bone from the longer leg once growth is complete to even out leg lengths. Surgery to lengthen the shorter leg. This surgery is more involved than surgery to shorten a leg. During this surgery, cuts are made in the leg bone. An external metal frame and bar are attached to the leg bone. This frame and bar slowly pull on the leg bone, lengthening it. The frame and bar must be worn constantly for months to years. When the frame and bar are removed, a leg cast is required for several months. This surgery requires careful and continued follow-up with the surgeon to be sure that healing is going well.
Small or mild length leg discrepancies (LLD), i.e., below 3.0 cm, have been considered as enough to cause orthopaedic changes such as lumbar pain, stress fractures and osteoarthritis on lower limbs (LLLL) joints. In addition to the classification by its magnitude, discrepancies can also be categorized according to etiology, being structural when a difference is noted between bone structures' length or functional as a result of mechanical changes on the lower limb, and are found in 65% - 70% of the healthy population.
Causes
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.
Symptoms
Faulty feet and ankle structure profoundly affect leg length and pelvic positioning. The most common asymmetrical foot position is the pronated foot. Sensory receptors embedded on the bottom of the foot alert the brain to the slightest weight shift. Since the brain is always trying to maintain pelvic balance, when presented with a long left leg, it attempts to adapt to the altered weight shift by dropping the left medial arch (shortening the long leg) and supinating the right arch to lengthen the short leg.1 Left unchecked, excessive foot pronation will internally rotate the left lower extremity, causing excessive strain to the lateral meniscus and medial collateral knee ligaments. Conversely, excessive supination tends to externally rotate the leg and thigh, creating opposite knee, hip and pelvic distortions.
Diagnosis
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
Treatment for an LLD depends on the amount of difference and the cause, if known. The doctor will discuss treatment options carefully with you and your child before any decisions are made. It is important to note that treatment is planned with the child?s final height and leg lengths in mind, not the current leg lengths. Treatment is generally not needed if the child?s final LLD is predicted to be 2 centimeters or less at full height. However, the child should return to an orthopaedic doctor by age 10 for re-evaluation. Treatment is often recommended for LLDs predicted to be more than 2 centimeters at full height. If treatment is done, it usually doesn?t begin until the child starts walking. Possible treatment options include, A ?lift? in one shoe to level the child?s hips. This is often the only treatment needed for small discrepancies.
leg length discrepancy exercises
Surgical Treatment
Surgery to shorten the longer leg. This is less involved than lengthening the shorter leg. Shortening may be done in one of two ways. Closing the growth plate of the long leg 2-3 years before growth ends (around age 11-13), letting the short leg catch up. This procedure is called an epiphysiodesis. Taking some bone from the longer leg once growth is complete to even out leg lengths. Surgery to lengthen the shorter leg. This surgery is more involved than surgery to shorten a leg. During this surgery, cuts are made in the leg bone. An external metal frame and bar are attached to the leg bone. This frame and bar slowly pull on the leg bone, lengthening it. The frame and bar must be worn constantly for months to years. When the frame and bar are removed, a leg cast is required for several months. This surgery requires careful and continued follow-up with the surgeon to be sure that healing is going well.