ABSTRACT
In cerebral paralysis the outstanding feature is that of inability to carry out movements with one or more bodily segments. In addition to this primary inability, in those cases in which the paralysis has existed for long periods of time it will be noted that certain muscles are tightly contracted. The limb of which these muscles are a part is not held in a natural position, but it is rigid and flexed. The muscular rigidity and the flexion just mentioned, which together are called contracture, begin in some instances within a few days after the destruction of the cerebral cells or connections. The early appearance of rigidity is usually in the cases where there has been a destruction of the cerebral cortex. In other instances the contracture may not develop for weeks. The contracted state which develops late is most frequently associated with subcortical lesions of the motor, or pyramidal, tract in some part of its course from the internal capsule downwards. In the long standing cases, in addition to the paralysis and contracture there may be shrinkage of the muscles. When this atrophy is investigated it is found to be dissimilar to that produced by lesions of the lower neuron (as in poliomyelitis), in that the muscles do not completely waste 168away, and in that its physiological reactions, especially noted in connection with electrical stimulation, remain normal. Examination of the muscle cells under the microscope in cases of cerebral paralysis shows that they have retained their normal appearance, and that they cannot he differentiated from the cells of unparalyzed muscles.
