Deformities
Although neurosurgery can result in greatly improved arm function, a child with brachial plexus palsy may be left with deformities - the most obvious being a short arm - and other effects of residual muscle weakness. A short arm is a function of the severity of injury. In children with severe injury and persistent severe weakness, the affected arm may be up to 4 inches shorter than the other arm. The child should use the affected arm as much as possible in daily activities to minimize the problem.
Specific deformities can be categorized as follows:
Shoulder
limited adduction
internal rotation
contractures
humeral head deformities
shoulder joint deformities
Elbow
flexion contractures
extension contractures
limited active supination
dislocation of radial head
Hand and Wrist
paralytic deformities
Surgery
At birth, the bones, muscles, tendons and ligaments of the shoulder and arm are relatively normal in their shape, location and relationship to each other, since they are only secondarily affected by the brachial plexus injury. As the child gets older, however, abnormal changes can develop in the shoulder, elbow and wrist joints. To minimize these changes and the resulting stiffness, it is crucial that the child begin daily exercises emphasizing joint motion as soon as the diagnosis is made.
After maximal recovery from the brachial plexus palsy, residual orthopaedic problems may prevent optimal function of the arm and hand. At this time, a detailed evaluation by a pediatric orthopaedic surgeon may be of benefit. Such an evaluation can identify surgical interventions-releasing muscles, transferring tendons, rotating bones or fusing joints-which may increase the function of the arm. Since each child with brachial plexus palsy has a unique combination of muscle weakness, joint stiffness and bony deformity, the precise surgical approach will vary for each individual.
In general, younger patients have fewer bony deformities of the shoulder and arm, and early surgery utilizing muscle releases and tendon transfers can be helpful in optimizing function and preventing future problems. Depending on the particular problem of each child, these procedures may be performed separately or in combination.
At the shoulder, the latissimus dorsi, teres major, teres minor, infraspinatus, pectoralis major, subscapularis, supraspinatus and serratus anterior muscles can be released or transferred to optimize range of motion and strength. A frequently performed surgical procedure is called "Sever-L'Episcopo," which involves muscle releases, tendon lengthenings and tendon transfers at the shoulder.
In older children, the abnormalities in bones and muscles become more pronounced, which means that different surgical procedures, such as rotational osteotomies of the arm bone and fusion of the shoulder joint, are required. The osteotomy of the arm bone (humerus) creates a more functional relationship between the elbow and the hand. The shoulder joint fusion is the technique of choice for treating a painful, unstable shoulder with poor deltoid muscle function. This procedure is almost always performed after the bones have fully matured, which is at approximately 14 years of age in girls and 16 years in boys. In addition, tendon transfers and muscle releases at the elbow, forearm, wrist and hand are sometimes recommended.
