Treatment Options for Limb Length Discrepancy

Frequently asked question - Limb Lengthening


When my daughter’s walking pattern changed, our pediatrician mentioned she may have leg length discrepancy. What are the treatment options for this?


Leg length discrepancy (LLD)—an unequal length in one’s legs—is a common condition seen by pediatric orthopedic specialists. We determine whether treatment is necessary by location of discrepancy, the predicted growth difference at skeletal maturity, and in your case, the goals of your daughter and your family.


LLD can be caused from a congenital condition (present at birth), or can develop over time from growth-plate (areas of growing tissue in children and adolescents) injuries and/or infections of the bone and joints. LLD can also develop as a consequence of cancer treatment.


LLD is evaluated and diagnosed by careful physical examination. We take an X-ray of both legs from hips to ankles to calculate the difference in each bone and to evaluate the health and presence of growth plates. Since an adolescent’s growth plates develop at different rates, we sometimes take an X-ray of the patient’s hand to determine the amount of growth remaining.


Based on the predicted leg-length difference at skeletal maturity, recommended treatments may include shoe lifts, surgery to shorten the longer leg, surgery to lengthen the shorter leg or a combination of the above.


Shortening of the longer leg is generally best for LLD between 0.5 and two inches. This can be achieved either through closure of open growth plates at an age predicted to equalize leg lengths, or closed femoral shortening if the growth plates are closed. Both procedures allow for early weight bearing and return to activities.


Lengthening of the shorter leg is generally reserved for LLD over two inches. This lengthening can be achieved by moving segments of bone slowly apart (1 mm per day) by an external fixator or a magnetically-driven internal rod. This internal distraction rod is new technology, and is typically reserved for use in femurs in children older than age 11 and in tibias over age 14. Postoperative rehabilitation for both types of procedures can be strenuous, with frequent physical therapy visits and limitation of activity over a period of six months.


We strive to educate patients and families on the treatment options and predicted challenges in order to develop a treatment plan that meets each patient’s goals and expectations. Have your daughter evaluated by a pediatric orthopedic specialist. If she has LLD, ask your physician about all treatment options available for her particular condition.


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Dr. Miller’s Office Locations

St. Louis Children's Hospital

4S60, Suite 1B

One Children's Place

St Louis, MO 63110

St. Louis Children's Specialty Care Center

13001 N Outer Forty Rd., Suite 1C

Town and Country, MO 63017

Appointments available at 7am on Tuesdays, and some Saturday appointments available from 7:30am-12pm. For specifics, please call (314) 514-3500.

Shriners Hospital for Children

4400 Clayton Ave.

St Louis, MO 63110


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