Leg length discrepancy

How does a doctor know my child has a leg length discrepancy?

Diagnostic procedures include a complete medical history of the patient and a physical examination by an orthopedic surgeon. The doctor will use both of these tools to determine the underlying cause of the problem.

During the physical exam, your child's doctor will probably take two measurements of your child's legs with a tape measure.

• One measurement, to determine the "real" length of the leg will be taken from the middle of the hip down to the ankle.
• The other, the "apparent" length, will be taken from the naval area. The discrepancy determined by these two measurements might be different if the "apparent" length is affected by hip position, suggesting a functional discrepancy.

The doctor may also ask your child to stand with a block under the shorter leg to confirm the measurement estimate the amount of correction that feels best. The doctor will also want to confirm the measurement with the following diagnostic tests:

• X-rays - A diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film
• Computerized Tomography Scan (also called a CT or CAT scan) - A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called "slices"), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat and organs. CT scans are more detailed than general X-rays