Overview
Leg length discrepancy (LLD) affects about 70% of the general population, and can be either structural - when the difference occurs in bone structures - or functional, because of mechanical changes at the lower limbs. The discrepancy can be also classified by its magnitude into mild, intermediate, or severe. Mild LLD has been particularly associated with stress fracture, low back pain and osteoarthritis, and when the discrepancy occurs in subjects whose mechanical loads are increased by their professional, daily or recreational activities, these orthopaedic changes may appear early and severely. The aim of this study was to analyze and compare ground reaction force (GRF) during gait in runners with and without mild LLD. Results showed that subjects with mild LLD of 0.5 to 2.0 cm presented higher values of minimum vertical GRF (0.57 ? 0.07 BW) at the shorter limb compared to the longer limb (0.56 ? 0.08 BW) Therefore, subjects with mild LLD adopt compensatory mechanisms that cause additional overloads to the musculoskeletal system in order to promote a symmetrical gait pattern as showed by the values of absolute symmetric index of vertical and horizontal GRF variables.
Causes
A patient?s legs may be different lengths for a number of reasons, including a broken leg bone may heal in a shorter position, particularly if the injury was severe. In children, broken bones may grow faster for a few years after they heal, resulting in one longer leg. If the break was near the growth center, slower growth may ensue. Children, especially infants, who have a bone infection during a growth spurt may have a greater discrepancy. Inflammation of joints, such as juvenile arthritis during growth, may cause unequal leg length. Compensation for spinal or pelvic scoliosis. Bone diseases such as Ollier disease, neurofibromatosis, or multiple hereditary exostoses. Congenital differences.
Symptoms
The symptoms of limb deformity can range from a mild difference in the appearance of a leg or arm to major loss of function of the use of an extremity. For instance, you may notice that your child has a significant limp. If there is deformity in the extremity, the patient may develop arthritis as he or she gets older, especially if the lower extremities are involved. Patients often present due to the appearance of the extremity (it looks different from the other side).
Diagnosis
The evaluation of leg length discrepancy typically involves sequential x-rays to measure the exact discrepancy, while following its progression. In addition, an x-ray of the wrist allows us to more carefully age your child. Skeletal age and chronological age do not necessarily equal each other and frequently a child's bone age will be significantly different than his or her stated age. Your child's physician can establish a treatment plan once all the facts are known: the bone age, the exact amount of discrepancy, and the cause, if it can be identified.
Non Surgical Treatment
The way in which we would treat a LLD would depend on whether we have an anatomical or functional difference. To determine which one is causing the LLD you will need to get your legs measured. This is the easiest way to determine if it is anatomical or functional. With a functional LLD we must first determine the cause and treat the cause. Should the cause be one that is not correctable then we may need to treat the LLD as if it were an anatomical or may have to treat the opposite leg to improve one's gait. As for the anatomical LLD, we may start off with a heel lift only in the shoe and follow up to see if we will need to put the lift full sole on the bottom of the shoe. This is determined by the affects that a heel lift in one shoe may have on that knee. Should the LLD be more than 1/4 inch we usually recommend starting between 1/8 inch to 1/4 inch less than the actual amount and let the body adjust to the change and then raise up to the measured amount later.
Surgical Treatment
The type of surgery depends on the type of problem. Outpatient procedures may be used to alter the growth of the limb. This is often done through small incisions. If an outpatient procedure is done, your child can continue with most regular activities. Other times, surgery may be very involved and require the use of an external device that is attached to the limb with pins and wires. This device may be left on for months to correct the deformity or lengthen the leg. If this type of surgery is required, your child will be making weekly visits to Cincinnati Children's.
Leg length discrepancy (LLD) affects about 70% of the general population, and can be either structural - when the difference occurs in bone structures - or functional, because of mechanical changes at the lower limbs. The discrepancy can be also classified by its magnitude into mild, intermediate, or severe. Mild LLD has been particularly associated with stress fracture, low back pain and osteoarthritis, and when the discrepancy occurs in subjects whose mechanical loads are increased by their professional, daily or recreational activities, these orthopaedic changes may appear early and severely. The aim of this study was to analyze and compare ground reaction force (GRF) during gait in runners with and without mild LLD. Results showed that subjects with mild LLD of 0.5 to 2.0 cm presented higher values of minimum vertical GRF (0.57 ? 0.07 BW) at the shorter limb compared to the longer limb (0.56 ? 0.08 BW) Therefore, subjects with mild LLD adopt compensatory mechanisms that cause additional overloads to the musculoskeletal system in order to promote a symmetrical gait pattern as showed by the values of absolute symmetric index of vertical and horizontal GRF variables.
Causes
A patient?s legs may be different lengths for a number of reasons, including a broken leg bone may heal in a shorter position, particularly if the injury was severe. In children, broken bones may grow faster for a few years after they heal, resulting in one longer leg. If the break was near the growth center, slower growth may ensue. Children, especially infants, who have a bone infection during a growth spurt may have a greater discrepancy. Inflammation of joints, such as juvenile arthritis during growth, may cause unequal leg length. Compensation for spinal or pelvic scoliosis. Bone diseases such as Ollier disease, neurofibromatosis, or multiple hereditary exostoses. Congenital differences.
Symptoms
The symptoms of limb deformity can range from a mild difference in the appearance of a leg or arm to major loss of function of the use of an extremity. For instance, you may notice that your child has a significant limp. If there is deformity in the extremity, the patient may develop arthritis as he or she gets older, especially if the lower extremities are involved. Patients often present due to the appearance of the extremity (it looks different from the other side).
Diagnosis
The evaluation of leg length discrepancy typically involves sequential x-rays to measure the exact discrepancy, while following its progression. In addition, an x-ray of the wrist allows us to more carefully age your child. Skeletal age and chronological age do not necessarily equal each other and frequently a child's bone age will be significantly different than his or her stated age. Your child's physician can establish a treatment plan once all the facts are known: the bone age, the exact amount of discrepancy, and the cause, if it can be identified.
Non Surgical Treatment
The way in which we would treat a LLD would depend on whether we have an anatomical or functional difference. To determine which one is causing the LLD you will need to get your legs measured. This is the easiest way to determine if it is anatomical or functional. With a functional LLD we must first determine the cause and treat the cause. Should the cause be one that is not correctable then we may need to treat the LLD as if it were an anatomical or may have to treat the opposite leg to improve one's gait. As for the anatomical LLD, we may start off with a heel lift only in the shoe and follow up to see if we will need to put the lift full sole on the bottom of the shoe. This is determined by the affects that a heel lift in one shoe may have on that knee. Should the LLD be more than 1/4 inch we usually recommend starting between 1/8 inch to 1/4 inch less than the actual amount and let the body adjust to the change and then raise up to the measured amount later.
Surgical Treatment
The type of surgery depends on the type of problem. Outpatient procedures may be used to alter the growth of the limb. This is often done through small incisions. If an outpatient procedure is done, your child can continue with most regular activities. Other times, surgery may be very involved and require the use of an external device that is attached to the limb with pins and wires. This device may be left on for months to correct the deformity or lengthen the leg. If this type of surgery is required, your child will be making weekly visits to Cincinnati Children's.