Is Your Backache Caused by Your Leg Length?-2

Having legs of different length is recognised as a common cause of low back pain; but as I said the other day usually the body compensates for the difference. These compensations or adaptations place increased stress on various joints throughout the body and hence the pains.

Not surprisingly this condition affects growing children and they can show some funny signs when you examine them. For example one of the basic observations that we do is to look at the relative heights of the knees with the child lying flat on his/her back; a higher knee means a longer leg in the thigh(femur bone) segment.

Usually the bone on the inside of the ankle is also lower on the longer leg when you have the legs stretched out. Easy! there is a subjective dianosis based on clinical examination and suspicion. That’s fine until you see that it’s the other leg that is actually longer at the ankle!!! So what’s the message here? Be very careful about jumping to conclusions with any patient but especially with children.

This simple example shows why the definitive test is the X-ray called the scanogram, because the radiologist views and measures the lower limbs (yes both) from hips to toes. The first place to look is in the hip joints to assess the alignment of the hip joint which is made up of the head of the femur and a cavity in the side of each hip called the acetabulum.

As podiatrists we are able to prescribe the local treatment based on biomechanical and gait analysis. This is only part of the team approach I referred to though. In younger people regular re-asssessment is needed to see if any correction has occured and then the local foot therapy will change. In older people the foot therapy is usually permanent. This is the situation in many people who have had hip replacement surgery. Which reminds me of a story.

I have a patient who has been a very successful ballroom dancer for more than 50 years. When she required hip replacement surgery she did her research and was distressed to find out that she might end up with a shorter leg, like some of her friends. As a result she threatened her surgeon – who happens to be “the hip expert of Johannesburg” – that she wanted a guarantee that her legs would still be equal after the operation. Believe me when I tell you that she is still dancing!

Take care of your pair – see a podiatrist