Leg Length Discrepancy Triggering Hip Pain

posted on 26 Apr 2015 23:55 by gallowayskwxfblcmz
Overview

Have you noticed that your pants always fit a little weird or that you are always leaning to one leg when standing for awhile? If so, one of your legs may be longer than the other. This is known as a leg length discrepancy. There are two main reasons for a leg length discrepancy. One reason is that one of your leg bones (tibia or femur) is longer on one side. This is referred to as a true leg length discrepancy because the actual length of your bones is different. A second reason is that your pelvic bone may be rotated on one side making it appear that one leg is longer than the other. This is referred to as an apparent leg length discrepancy because the actual length of your leg bones is not different. In order to figure out if you have a true or apparent leg length discrepancy, your doctor may take an x-ray to measure the length of your leg bones or a simple measurement from your belly button to your ankle can help determine the reason. Over time, the leg length difference can cause stress on your low back, hips and knees, which may cause pain or discomfort.Leg Length Discrepancy

Causes

There are many causes of leg length discrepancy. Structural inequality is due to interference of normal bone growth of the lower extremity, which can occur from trauma or infection in a child. Functional inequality has many causes, including Poliomyelitis or other paralytic deformities can retard bone growth in children. Contracture of the Iliotibial band. Scoliosis or curvature of the spine. Fixed pelvic obliquity. Abduction or flexion contraction of the hip. Flexion contractures or other deformities of the knee. Foot deformities.

Symptoms

Back pain along with pain in the foot, knee, leg and hip on one side of the body are the main complaints. There may also be limping or head bop down on the short side or uneven arm swinging. The knee bend, hip or shoulder may be down on one side, and there may be uneven wear to the soles of shoes (usually more on the longer side).

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

In some circumstances, the physician will recommend a non-surgical form of treatment. Non-surgical treatments include orthotics and prosthetics. Orthotics are a special type of lift placed in or on a shoe that can be used in the treatment of leg length discrepancies between two and six centimeters. In pediatric patients who have large discrepancies and are not good candidates for other treatment forms, prosthetics can be helpful.

Leg Length Discrepancy

Surgical Treatment

Large leg length inequalities can be treated by staged lengthenings or by simultaneous ipsilateral femoral and tibial lengthenings. Additionally, lengthenings can be combined with appropriately timed epiphysiodesis in an effort to produce leg length equality. Staged lengthenings are often used for congenital deficiencies such as fibular hemimelia, in which 15 cm or more may be needed to produce leg length equality. We typically plan for the final lengthening to be completed by age 13 or 14 years, and allow at least 3 years between lengthenings. Lengthening of both the tibia and femur simultaneously requires aggressive therapy and treatment of soft tissue contractures. Curran et al[57] reported the need for surgical release of soft tissue contractures in 3 of 8 patients treated with simultaneous ipsilateral femoral and tibial lengthenings. Lengthening over an IM nail can be done in an effort to decrease the amount of time the fixator needs to be worn and to prevent angular malalignment. This technique requires that the patient be skeletally mature and it carries a higher risk of osteomyelitis (up to 15%). Additionally, if premature consolidation occurs, a repeat corticotomy is more difficult.