Overview
Neuromuscular. Muscle imbalance causing different pull on pelvis (anterior superior Ilium or posterior inferior ilium). Muscle tightness/shortness especially piriformis (which lead to an external rotation of the femur thus shortening of the leg) and QL (raising ipsilateral iliac crest). Genu recurvatum, valgus, varus. Asymmetrical fallen arches or over pronation. Polio, Cerebral palsy. Trauma. Fracture. Injury epiphyseal plate. Iatrogenic (such as hip or knee surgery). Idiopathic. Hip disorder (such Legg-Perthes-Calve? or Slipped capital femoral epiphysis). Advanced degenerative changes. Causes Some limb-length differences are caused by actual anatomic differences from one side to the other (referred to as structural causes). The femur is longer (or shorter) or the cartilage between the femur and tibia is thicker (or thinner) on one side. There could be actual deformities in one femur or hip joint contributing to leg length differences from side to side. Even a small structural difference can amount to significant changes in the anatomy of the limb. A past history of leg fracture, developmental hip dysplasia, slipped capital femoral epiphysis (SCFE), short neck of the femur, or coxa vara can also lead to placement of the femoral head in the hip socket that is offset. The end-result can be a limb-length difference and early degenerative arthritis of the hip. Symptoms 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. Diagnosis The most accurate method to identify leg (limb) length inequality (discrepancy) is through radiography. It?s also the best way to differentiate an anatomical from a functional limb length inequality. Radiography, A single exposure of the standing subject, imaging the entire lower extremity. Limitations are an inherent inaccuracy in patients with hip or knee flexion contracture and the technique is subject to a magnification error. Computed Tomography (CT-scan), It has no greater accuracy compared to the standard radiography. The increased cost for CT-scan may not be justified, unless a contracture of the knee or hip has been identified or radiation exposure must be minimized. However, radiography has to be performed by a specialist, takes more time and is costly. It should only be used when accuracy is critical. Therefore two general clinical methods were developed for assessing LLI. Direct methods involve measuring limb length with a tape measure between 2 defined points, in stand. Two common points are the anterior iliac spine and the medial malleolus or the anterior inferior iliac spine and lateral malleolus. Be careful, however, because there is a great deal of criticism and debate surrounds the accuracy of tape measure methods. If you choose for this method, keep following topics and possible errors in mind. Always use the mean of at least 2 or 3 measures. If possible, compare measures between 2 or more clinicians. Iliac asymmetries may mask or accentuate a limb length inequality. Unilateral deviations in the long axis of the lower limb (eg. Genu varum,?) may mask or accentuate a limb length inequality. Asymmetrical position of the umbilicus. Joint contractures. Indirect methods. Palpation of bony landmarks, most commonly the iliac crests or anterior iliac spines, in stand. These methods consist in detecting if bony landmarks are at (horizontal) level or if limb length inequality is present. Palpation and visual estimation of the iliac crest (or SIAS) in combination with the use of blocks or book pages of known thickness under the shorter limb to adjust the level of the iliac crests (or SIAS) appears to be the best (most accurate and precise) clinical method to asses limb inequality. You should keep in mind that asymmetric pelvic rotations in planes other than the frontal plane may be associated with limb length inequality. A review of the literature suggest, therefore, that the greater trochanter major and as many pelvic landmarks should be palpated and compared (left trochanter with right trochanter) when the block correction method is used. Non Surgical Treatment A properly made foot orthotic can go a long way in substituting additional millimeters or centimeter on the deficient side. Additional full length inserts are added to the shorter side bringing the runner closer to symmetrical. Heel lifts do not work in runners because when you run you may land on your heel but the rest of the time you are on your forefoot then your toes pushing off. The right custom-made, biomechanical orthotic can address the underlying cause of your pain. Abnormal joint position, overpronation or foot rigidity can be addressed and the biomechanics normalized. San Diego Running Institute orthotics are custom molded to your foot and are designed with your specific body weight, leg length discrepancy, and activity in mind. The restoration of correct mechanical function takes the abnormal stress from the uneven side and allows the body to heal naturally. how to increase height naturally after 18 Surgical Treatment Lengthening is usually done by corticotomy and gradual distraction. This technique can result in lengthenings of 25% or more, but typically lengthening of 15%, or about 6 cm, is recommended. The limits of lengthening depend on patient tolerance, bony consolidation, maintenance of range of motion, and stability of the joints above and below the lengthened limb. Numerous fixation devices are available, such as the ring fixator with fine wires, monolateral fixator with half pins, or a hybrid frame. The choice of fixation device depends on the desired goal. A monolateral device is easier to apply and better tolerated by the patient. The disadvantages of monolateral fixation devices include the limitation of the degree of angular correction that can concurrently be obtained; the cantilever effect on the pins, which may result in angular deformity, especially when lengthening the femur in large patients; and the difficulty in making adjustments without placing new pins. Monolateral fixators appear to have a similar success rate as circular fixators, especially with more modest lengthenings (20%). Comments are closed.
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