It will be much easier if you understand the problems and the thinking behind the treatment, so this introduction is written to help supplement and reinforce the advice and information given to you at the hospital. Skeletal muscles allow us to move, to stand, and by co-ordinated work, to perform the variety of movements necessary for all the challenges of daily living. Each muscle in the body is composed of a number of muscle fibres. There are different types of muscle fibres and the number and proportion of each type in any muscle depends on what sort of work that the muscle normally does. Muscles are attached to bones through specially adapted parts of the muscle, called tendons.
Muscles acting over joints are ually evenly balanced.
The rate at which this happens, and therefore the rate at which weakness occurs, varies somewhat between children with the same condition. It is important to realise that some muscles are affected earlier than others, and this upsets the normal balance of strength between the muscle groups. When muscles become weak or are not used, they lose their extensibility and so do all the associated ligaments and tendons. This means that the joint becomes stiff and tight, usually more in one direction than the other, resulting in a contracture or fixed position of the joint, which in turn leads to a deformity. If the joint can no longer move normally, the muscle cannot work normally and becomes weaker from disuse.