Overview
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.
Causes
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.
Symptoms
The most common symptom of all forms of LLD is chronic backache. In structural LLD the sufferer may also experience arthritis within the knee and hip are, flank pain, plantar fasciitis and metatarsalgia all on the side that is longer. Functional LLD sufferers will see similar conditions on the shorter side.
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
Treatment of leg length inequality involves many different approaches, such as orthotics, epiphysiodesis, shortening, and lengthening, which can be used alone or combined in an effort to achieve equalization of leg lengths. Leg length inequality of 2 cm or less is usually not a functional problem. Often, leg length can be equalized with a shoe lift, which usually corrects about two thirds of the leg length inequality. Up to 1 cm can be inserted in the shoe. For larger leg length inequalities, the shoe must be built up. This needs to be done for every shoe worn, thus limiting the type of shoe that the patient can wear. Leg length inequalities beyond 5 cm are difficult to treat with a shoe lift. The shoe looks unsightly, and often the patient complains of instability with such a large lift. A foot-in-foot prosthesis can be used for larger leg length inequalities. This is often done as a temporizing measure for young children with significant leg length inequalities. The prosthesis is bulky, and a fixed equinus contracture may result.
Surgical Treatment
Leg shortening is employed when LLD is severe and when a patient has already reached skeletal maturity. The actual surgery is called an osteotomy , which entails the removal of a small section of bone in the tibia (shinbone) and sometimes the fibula as well, resulting in the loss of around an inch in total height. Leg lengthening is a difficult third option that has traditionally had a high complication rate. Recently, results have improved somewhat with the emergence of a technique known as callotasis , in which only the outer portion of the bone (the cortex ) is cut, (i.e. a corticotomy ). This allows the bone to be more easily lengthened by an external fixation device that is attached to either side of the cut bone with pins through the skin. The ?ex-fix,' as it is sometimes called, is gradually adjusted by an orthopaedic surgeon, and healing can occur at the same time that the leg is being distracted , or lengthened over time. Unlike epiphysiodesis, leg lengthening procedures can be performed at almost any skeletal or chronological age.
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.
Causes
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.
Symptoms
The most common symptom of all forms of LLD is chronic backache. In structural LLD the sufferer may also experience arthritis within the knee and hip are, flank pain, plantar fasciitis and metatarsalgia all on the side that is longer. Functional LLD sufferers will see similar conditions on the shorter side.
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
Treatment of leg length inequality involves many different approaches, such as orthotics, epiphysiodesis, shortening, and lengthening, which can be used alone or combined in an effort to achieve equalization of leg lengths. Leg length inequality of 2 cm or less is usually not a functional problem. Often, leg length can be equalized with a shoe lift, which usually corrects about two thirds of the leg length inequality. Up to 1 cm can be inserted in the shoe. For larger leg length inequalities, the shoe must be built up. This needs to be done for every shoe worn, thus limiting the type of shoe that the patient can wear. Leg length inequalities beyond 5 cm are difficult to treat with a shoe lift. The shoe looks unsightly, and often the patient complains of instability with such a large lift. A foot-in-foot prosthesis can be used for larger leg length inequalities. This is often done as a temporizing measure for young children with significant leg length inequalities. The prosthesis is bulky, and a fixed equinus contracture may result.
Surgical Treatment
Leg shortening is employed when LLD is severe and when a patient has already reached skeletal maturity. The actual surgery is called an osteotomy , which entails the removal of a small section of bone in the tibia (shinbone) and sometimes the fibula as well, resulting in the loss of around an inch in total height. Leg lengthening is a difficult third option that has traditionally had a high complication rate. Recently, results have improved somewhat with the emergence of a technique known as callotasis , in which only the outer portion of the bone (the cortex ) is cut, (i.e. a corticotomy ). This allows the bone to be more easily lengthened by an external fixation device that is attached to either side of the cut bone with pins through the skin. The ?ex-fix,' as it is sometimes called, is gradually adjusted by an orthopaedic surgeon, and healing can occur at the same time that the leg is being distracted , or lengthened over time. Unlike epiphysiodesis, leg lengthening procedures can be performed at almost any skeletal or chronological age.
