1. The various methods of powering orthoses are described. 2. The details of control systems are given. 3. The applications of these systems are described.
1. Pathological changes occurred in the manubrio-sternal joint in 72 per cent of a series of sixty-one cases of ankylosing spondylitis. 2. In all the twenty-one patients over the age of thirty-five years the joint was undergoing a process of fusion that was found in only seven of sixty healthy persons in the same age group. 3. In the age groups twenty-five to forty-four, thirty-five out of forty-three patients with ankylosing spondylitis showed abnormality that was noted in but three of the forty healthy controls. 4. The changes in the manubrio-sternal joint are similar to those which occur in the sacro-iliac joint. 5. The accessibility of the manubrio-sternal joint makes it a convenient source of pathological material for the further histological study of the disease.
