My legs are not the same length, what now?

A common question I receive in the clinic from scoliosis clients is “my one leg is shorter than the other, should I get a shoe lift?” 

This seems like a logical solution, right? Simply add a shoe lift to even out the legs and all will be good.  Well maybe, maybe not!

As with most aspects with scoliosis the answer is more complicated.  There are several factors that contribute to the scoliosis, and leg length discrepancy could be one of these contributing factors, but we need to look at the entire picture before making a decision on how to treat the difference in leg lengths.

Much research has been done on leg bones of individuals with Adolescent Idiopathic Scoliosis (AIS).  It is clear that there frequently is asymmetry in the right and left leg with AIS.  However, the reason for the imbalance of the right and left leg is unclear and the correct treatment approach is even less clear.  Treatment options range from simply ignoring the differences, adding a shoe lift or other orthotic, to surgery.  To begin making the decision we need to see what kind of leg imbalance we have and where it is coming from.

Structural Leg Length Discrepancy (LLD)

Before adding a heel lift or orthotic to any shoe, we must first determine if there is a true leg length discrepancy, or if the body is simply fooling us.  A true leg length discrepancy is referred to as a structural discrepancy, where the treatment would be an orthotic, heel lift, or surgery.  This could be due to the following factors:

  • Congenital – The patient was born with tibia or femur bones that did not grow as long on one leg as the other.
  • Traumatic – This is important particularly during childhood, when the trauma is to the “growth plate” of one of the leg bones. This particular type of trauma will cause a slower rate of growth of the length of the bone as the child ages.
  • Degenerative – As arthritis erodes cartilage, it reduces the joint space between the hip or knee.
  • Neoplasm – Cancerous erosion or destruction of bone not only will have an impact on its strength, but also can shorten the long bone as a result of the damage.
Functional Leg Length Discrepancy

A functional leg length discrepancy is when there is an asymmetry or imbalance in the the body such as:

  • Pelvic shift
  • Joint capsular adhesion
  • Tight muscles or ligaments
  • Scoliosis
  • Trunk instability
  • Muscle mass asymmetry
  • Foot pronation or supination
  • Other muscle imbalances
The research shows that ⅔ of the population has a functional shorter right leg.  There are many theories as to why this is.
Measuring for LLD 

A physical therapist can measure for LLD  with a tape measure from the anterior superior iliac spine (a bony landmark on the front of the hip) to the medial malleolus (the inner ankle bone) of the same leg.  The measurement of the two (2) legs can be compared.  While using a tape measure is an easy, safe, and noninvasive means of assessing LLD, studies have shown  it is less reliable when compared to radiographic techniques such as x-ray or CT scan.  In order to confirm a structural difference between the right and left leg it is necessary to to have an x-ray.

Once a client has a confirmed LLD the clinicians can begin considering treatment options however there are still factors to consider.  Under 1.5 cm we traditionally do not use a shoe lift or other orthotic to even out the legs.

Take age into consideration

Traditionally with a minor LLD we will not add any lift or orthotic to a child that is still growing.  If you add a lift or orthotic it could even out  the weight bearing through both feet, seems good right?  Wrong!  A child might naturally even out their limb lengths with normal growth.  The shorter leg will automatically get more weight bearing, and therefore more stimulation to grow.   You want the extra weight on the shorter limb to stimulate the extra growth on that side, the shoe lift might in fact stop the body from self correcting.   

On the other hand, the LLD might be causing an increase in the scoliosis curve and rotation.  Before adding the lift to help scoliosis it is important to get two (2) standing x-rays.  One image without the lift, and the second with the shoe lift to determine how the spine compensates for and adjusts.  In addition do an Adams forward bend test with and without the shoe lift to see if the rib hump increases or decreases with the show lift

In some cases with certain scoliosis curve patterns a shoe lift can exacerbate and increase the scoliotic curve.  For example, if you add a heel lift to the right side it might facilitate the right hip to hike and increase the concavity of the lumbar curve or the convexity of the right thoracic curve.  

In conclusion, if you have one leg longer than the other there is no simple treatment solution. However, with scoliosis and an imbalance of legs lengths it is always a good idea to follow up with a schroth certified physical therapist, such as Scoliosis PT Jax.  A PT will work on postural alignment, stretching, strengthening, and breath work to ensure the best outcome for your scoliosis. 

Contact Donne՛ Ordile PT Schroth Certified at Scoliosis PT Jax
(904) 372-3161

References :

Burwell RG, Auija RK, Freeman BJ et Al found Patterns of extra-spinal left-right skeletal asymmetries and proximo distal disproportion in adolescent girls with lower spine scoliosis: ilio-femoral length asymmetry & bilateral tibial/foot length disproportions.  Stud Health inform. 2006: 123:101-105

Donatelli R. The biomechanics of the Foot and Ankle. F A Davis Co., 2006


Cole A, Burwell RG, Jacobs KJ:  Hip rotation, knee rotation and femoral anteversion in healthy subjects and in children with adolescent idiopathic scoliosis: relation of hip rotation to lateral spinal curves. Cin Ant 1990, 3:65

Erik Dalton, PhD, Short Leg Sundrome, Massage Magazine (2007)

Functional scoliosis caused by leg length discrepancy, Jan W. Raczkowski, Barara

Leg Length Inequality, J Manipulative Physiol Ther 1992 Nov-Dec: 15(9(;576-90)

True or apparent leg length discrepancy: which is a better predictor of short-term functional outcomes after total hip arthroplasty? J Geriatr Phys Ther. 2013 Oct-Dec;36(4):169-74 

For more information on scoliosis or leg length discrepancy set up a free discovery visit with Scoliosis PT Jax. Call (904) 372-3161 or leave a message on our contact page and we will get in touch ASAP!