Leg Length Discrepancy

Leg length discrepancy is when a child has one leg that is shorter than the other leg. This difference can range from very small and unnoticeable to several inches.  Mild leg length discrepancy is common and does not require any treatment. Larger differences may require treatment to help improve quality of life.

Causes

A common cause is a previous fracture that doesn’t heal correctly, including: 

• Bone heals in a shortened position
• Injuries to the muscles and tendons surrounding the broken bone
• Fracture involved the growth plate of the bone
• Bone grows faster after it heals

Less common causes include:

• Previous bone infection (especially if it occurs during infancy)
• Inflammatory joint diseases (such as from Juvenile Arthritis)
• Bone diseases (i.e., neurofibromatosis, multiple hereditary exostoses, Ollie’s disease)
• Dysplasia

Sometimes the cause is unknown. When the cause is unknown, it is called hemihypertrophy (if one leg is abnormally long) or hemiatrophy (if one leg is abnormally short). 

Signs & Symptoms

Although Leg Length Discrepancy is usually present at birth, the difference is usually too small to be seen. It’s only when a child grows, that the discrepancy becomes more noticeable. 

Over time, large, uncorrected discrepancies might cause:

• Back, hip or knee problems
• Uneven walking

However, mild discrepancies do not cause back or hip or knee problems, and usually do not affect the way a child walks.

Diagnosis

A discrepancy of the legs can be measured during a physical exam. Measuring the level of the hips, wooden blocks of known sizes may be used under the shorter leg to bring the hip higher. Radiographs may also be taken to measure the length of each bone. Your child will need to be followed in intervals by the physician to evaluate any changes in the difference of lengths.

Treatment

Non-Surgical

If your child’s leg length discrepancy will be less than two centimeters at the end of growth, your doctor may prescribe a shoe insert (also called an orthotic). If your child has some difficulties with walking, running or experiences back pain, shoe inserts may help, too.

Prosthetics are another non-surgical treatment for children with large limb length deficiencies who would not be a candidate for surgery.

Surgical

Medium and large limb length discrepancies might require surgery.  If our doctors and surgeons believe surgery is the best option for your child, we may recommend

• Leg lengthening surgery
• Leg shortening surgery

See more information

Congenital Limb Disorders

Orthopedic Rehabilitation