Short Leg

What leg length discrepancy is

Small differences in leg length are common and often go unnoticed. A discrepancy becomes relevant when it is large enough to change how a person stands and walks, or when it places uneven demands on the hips, knees and spine. Surgeons separate two situations. A true, or structural, discrepancy means the bones themselves differ in length. A functional discrepancy means the bones are similar but the limb behaves as though it were shorter, for example because of a tilted pelvis, a stiff hip, or a knee that will not fully straighten.

The causes are varied. A difference may be present from birth, or develop during childhood if a growth plate is injured by fracture or infection and one bone stops growing at the same rate as its counterpart. In adults it commonly follows a fracture that healed shortened, bone lost after injury or infection, or previous surgery on the hip or knee. Working out which type is present is the first step in deciding whether anything needs to be done.

Symptoms that often bring people in

• A limp, or the feeling of dropping toward one side while walking
• Standing with one knee bent, or walking on the toes of the shorter side
• Aching in the lower back, hip or knee that developed without a specific injury
• Shoulders or hips that look uneven, or uneven wear on the soles of shoes
• In children, a difference that appears to be increasing
• A leg that has felt shorter since a fracture, hip surgery or bone infection

How a leg length difference is evaluated

Evaluation combines examination with measurement. The examination looks at how the pelvis sits when standing, alignment of the whole limb, range of motion at the hip, knee and ankle, and how the person walks. Placing measured blocks under the shorter side shows how much correction levels the pelvis and whether it feels comfortable. Imaging distinguishes true from functional shortening and measures each segment, often with standing full-length X-rays. In a growing child, the assessment also considers skeletal maturity and whether the difference is likely to increase.

Treatment options in general terms

Many leg length differences need no treatment beyond confirming the cause. When treatment is considered, non-surgical measures come first.

• Observation over time. In children, following the difference as growth continues may be all that is required.
• Shoe lifts and orthotics. A lift inside the shoe or added to the sole can even out standing posture and gait.
• Therapy for functional discrepancy. Where stiffness or pelvic position is responsible, work on flexibility, strength and gait may address the cause.

Surgery may be discussed when a difference is large, when symptoms persist that a lift cannot manage, or when it accompanies deformity or bone loss.

• Growth modulation. In a child still growing, a procedure that slows growth at a growth plate on the longer side may allow the limbs to even out over time.
• Shortening of the longer limb. In a skeletally mature patient, a segment of the longer bone may be removed and the bone stabilized at its new length.
• Limb lengthening. The shorter bone is divided and then gradually separated in very small daily increments, so new bone forms in the gap. This can be done with a circular external frame using the Ilizarov method, and may be combined with correction of angulation or rotation.

What to expect when you consult Dr. Wolfson

Dr. Wolfson trained in the Ilizarov method of limb lengthening, reconstruction and deformity correction, and treats leg length difference in children and adults. A consultation generally involves measuring the limbs rather than estimating, identifying whether the shortening is structural or functional, and discussing whether simple measures are likely to be enough. Related pages cover malunion and short stature.

This page provides general information about leg length discrepancy and is not medical advice. It is not a substitute for examination, imaging and diagnosis by a qualified physician. Every case is different and requires individual evaluation. If you have severe pain, an obvious deformity, loss of function, fever, or an injury from a significant accident, seek medical care promptly.

Contact Dr. Wolfson if you would like to setup an appointment. If you are a new patient, please book all in-person appointments with Dr. Wolfson via telephone.

If you live outside of the San Francisco Bay Area, you can request a complimentary phone consultation with Dr. Wolfson to assess your case. Please call or e-mail us to set up your complimentary consultation.

Call: (415) 221-4400

E-mail: [email protected]