Leg Length Discrepancy Running

posted on 29 Apr 2015 10:49 by juliana8decker1
Overview

Surgical options in leg length discrepancy treatment include procedures to lengthen the shorter leg, or shorten the longer leg. Your child's physician will choose the safest and most effective method based on the aforementioned factors. No matter the surgical procedure performed, physical therapy will be required after surgery in order to stretch muscles and help support the flexibility of the surrounding joints. Surgical shortening is safer than surgical lengthening and has fewer complications. Surgical procedures to shorten one leg include removing part of a bone, called a bone resection. They can also include epiphysiodesis or epiphyseal stapling, where the growth plate in a bone is tethered or stapled. This slows the rate of growth in the surgical leg.Leg Length Discrepancy

Causes

The causes of LLD are many, including a previous injury, bone infection, bone diseases (dysplasias), inflammation (arthritis) and neurologic conditions. Previously broken bones may cause LLD by healing in a shortened position, especially if the bone was broken in many pieces (comminuted) or if skin and muscle tissue around the bone were severely injured and exposed (open fracture). Broken bones in children sometimes grow faster for several years after healing, causing the injured bone to become longer. Also, a break in a child?s bone through a growth center (located near the ends of the bone) may cause slower growth, resulting in a shorter extremity. Bone infections that occur in children while they are growing may cause a significant LLD, especially during infancy. Bone diseases may cause LLD, as well; examples are neurofibromatosis, multiple hereditary exostoses and Ollier disease. Inflammation of joints during growth may cause unequal extremity length. One example is juvenile rheumatoid arthritis. Osteoarthritis, the joint degeneration that occurs in adults, very rarely causes a significant LLD.

Symptoms

Many people walk around with LLD?s of up to 2 cm. and not even know it. However, discrepancies above 2 cm. becomes more noticeable, and a slight limp is present. But even up to 3 cm. a small lift compensates very well, and many patients are quite happy with this arrangement. Beyond 3 cm. however, the limp is quite pronounced, and medical care is often sought at that point. Walking with a short leg gait is not only unsightly, but increases energy expenditure during ambulation. It could also put more stress on the long leg, and causes functional scoliosis. Where the discrepancy is more severe, walking becomes grotesque or virtually impossible.

Diagnosis

Leg length discrepancy may be diagnosed during infancy or later in childhood, depending on the cause. Conditions such as hemihypertrophy or hemiatrophy are often diagnosed following standard newborn or infant examinations by a pediatrician, or anatomical asymmetries may be noticed by a child's parents. For young children with hemihypertophy as the cause of their LLD, it is important that they receive an abdominal ultrasound of the kidneys to insure that Wilm's tumor, which can lead to hypertrophy in the leg on the same side, is not present. In older children, LLD is frequently first suspected due to the emergence of a progressive limp, warranting a referral to a pediatric orthopaedic surgeon. The standard workup for LLD is a thorough physical examination, including a series of measurements of the different portions of the lower extremities with the child in various positions, such as sitting and standing. The orthopaedic surgeon will observe the child while walking and performing other simple movements or tasks, such as stepping onto a block. In addition, a number of x-rays of the legs will be taken, so as to make a definitive diagnosis and to assist with identification of the possible etiology (cause) of LLD. Orthopaedic surgeons will compare x-rays of the two legs to the child's age, so as to assess his/her skeletal age and to obtain a baseline for the possibility of excessive growth rate as a cause. A growth chart, which compares leg length to skeletal age, is a simple but essential tool used over time to track the progress of the condition, both before and after treatment. Occasionally, a CT scan or MRI is required to further investigate suspected causes or to get more sophisticated radiological pictures of bone or soft tissue.

Non Surgical Treatment

The non-surgical intervention is mainly usedfor the functional and environmental types of leg length discrepancies. It is also applied to the mild category of limb length inequality. Non-surgical intervention consists of stretching the muscles of the lower extremity. This is individually different, whereby the M. Tensor Fascia latae, the adductors, the hamstring muscles, M. piriformis and M. Iliopsoas are stretched. In this non-surgical intervention belongs also the use of shoe lifts. These shoe lifts consists of either a shoe insert (up to 10-20mm of correction), or building up the sole of the shoe on the shorter leg (up to 30-60mm of correction). This lift therapy should be implemented gradually in small increments. Several studies have examined the treatment of low back pain patients with LLD with shoe lifts. Gofton obtained good results: the patients experienced major or complete pain relief that lasted upon follow-up ranging from 3 to 11 years. Helliwell also observed patients whereby 44% experienced complete pain relief, and 45% had moderate or substantial pain relief. Friberg found that 157 (of 211) patients with LBP, treated with shoe lifts, were symprom-free after a mean follow-up of 18 months.

Leg Length Discrepancy

Surgical Treatment

Shortening techniques can be used after skeletal maturity to achieve leg length equality. Shortening can be done in the proximal femur using a blade plate or hip screw, in the mid-diaphysis of the femur using a closed intramedullary (IM) technique, or in the tibia. Shortening is an accurate technique and involves a much shorter convalescence than lengthening techniques. Quadriceps weakness may occur with femoral shortenings, especially if a mid-diaphyseal shortening of greater than 10% is done. If the femoral shortening is done proximally, no significant weakness should result. Tibial shortening can be done, but there may be a residual bulkiness to the leg, and risks of nonunion and compartment syndrome are higher. If a tibial shortening is done, shortening over an IM nail and prophylactic compartment release are recommended. We limit the use of shortenings to 4 to 5 cm leg length inequality in patients who are skeletally mature.