It is hard to get good information about long term complications of brachial plexus injuries. Many physicians and therapists do not want to be pessimistic when describing your child’s injury and how it will affect him or her in the future. And sadly, many doctors treating these injuries are simply unaware of the long term complications, in part because they are pediatric specialists who have never followed these children into adulthood and old age. Nevertheless, it is not merely important, but vital for you to understand the possible consequences “down the line”—many years or even decades after your child is born—even with the best possible outcome from treatment. Knowledge won’t prevent those consequences, but knowledge will allow you to prepare both you and your child for them, and help to reduce their impact to the greatest extent possible.
Some of the long term complications your child might experience are listed in the gold links to the left. This is not intended to be a list of every possibility, but just to give you an idea of the most common potential complications.
“Innervation” is one of those expensive words. Here it means to supply nerves, not just for movement and sensation, but also for normal growth and functioning of the affected muscles and bones. Any permanent brachial plexus injury decreases the body’s ability to supply nerves so that the affected areas (chest, upper back, shoulder, arm, elbow, forearm, wrist and hand) can function normally. While nerve grafting surgery has been useful in some cases it can never completely restore the nerve supply to the areas affected by the injury.
The strength and stamina of any region of the body is directly affected by how well the area is supplied with nerves. The lower the supply, the lower your strength and stamina. Lower nerve supply means there is a reduction in the actual number of functioning muscular units, and the muscular bundles that do remain literally shrink in size and strength. Fewer, smaller, weaker nerves means less strength and stamina. You should be aware, though, that there is a misconception in some circles that this problem can be “cured” by aggressive therapy and/or exercise. Appropriate exercise and therapy can unquestionably increase the “strength” and function of the muscle bundles that are still there and still functioning, but nothing can reverse the impact that lost nerve supply has on muscle tissue.
Impaired nerve supply has a profound impact on the normal movement of muscle groups. In order for your child’s arm to function properly, there has to be a balance in the muscle strength surrounding, and in the forces exerted across, the joints at the shoulder, elbow, wrist and fingers. A brachial plexus injury alters the balance of forces, and causes abnormal movement and function of joints. The net effect can be limitations in range of motion, dexterity and even in the formation and structure of the joint itself. In addition, years of abnormal movement cause abnormal “wear patterns” that greatly increase the risk of osteoarthritis in the joints, especially the shoulder.
Muscle Atrophy is the “shrinkage” of muscle tissue caused by a decreased or absent nerve supply and by a lack of muscle movement. The size or mass of the muscle tissue is visibly smaller than the same muscle group on the opposite side of the body. The extent of muscle atrophy correlates with the degree of loss of nerve supply (innervation). Exercise can increase muscle mass in some circumstances but only if there is sufficient nerve supply and surviving muscles cells after the injury. Range of motion exercises are very important.
Bone growth is stimulated by the forces applied to the bone. If a bone is subjected to increased force, it grows to accommodate the stress put on it. On the other hand, if abnormally low forces are applied, the bone fails to develop the strength and size it would otherwise acquire. Children with brachial plexus injuries who have reduced muscle mass also have reduced forces applied to growing bones, resulting in smaller and weaker bones. This fact is often clearly demonstrated by measuring the humerus, which is the large bone in the arm.
Proper joint function depends upon normal movement around the joint and a balance in the strength of the muscles that act upon the joint. Joint dysfunction can and does occur in the absence of a structurally deformed joint. The shoulder joint is the one most often significantly affected by a brachial plexus injury, but the elbow, wrist and finger joints can also be significantly impaired. Click here for a description of a major complication called glenohumeral dysplasia.
Osteoarthritis is a condition that occurs due to abnormal wear of joints. One of the greatest long term complications of a brachial plexus injury is the development of severe osteoarthritis, especially in the shoulder joint. The pain associated with this condition can result a reduced work life expectancy as workers are forced to limit activities or discontinue employment early due to the condition. In some severe cases joint replacement later in life may be necessary.
Muscular atrophy and impaired bone growth result in significant discrepancies in limb length and size that become much more visible as children grow into adulthood. This creates a noticeable deformity, the extent of which is related to the degree of nerve damage. This can be detected in younger children by measuring the length and circumference of the affected and unaffected arms and forearms.
The shoulder blade (scapula) is a triangular shaped bone that connects the arm bone (humerus) to the collar bone (clavicle). The outer edge of the shoulder blade forms the “socket” part of the shoulder joint. It is held in place by a group of muscles that are stimulated by nerves arising in part from the brachial plexus. When the brachial plexus is injured some of the muscles holding the shoulder blade in its normal position are weak and small. This weakness allows the shoulder blade to kick up and out into a “winged position”. The socket in the ball and socket of the shoulder joint (the glenoid fossa) is then placed in a different position relative to the top of the arm bone than it should be in. One result of this “winging” is abnormal positioning and functioning of the shoulder joint. Some new surgical procedures are being attempted to restore the socket to a more normal position with the hope of improving shoulder function and reducing the severity of any future development of osteoarthritis.
This is a common and often overlooked serious long term effect of damage to the nerve supply to the shoulder area. The shoulder is a ball and socket joint. The ball in the joint is at the top of the arm bone (humerus) while the socket is in the shoulder blade (scapula). [See diagram below.] When a child is born at about forty weeks of gestation, the joint is not fully developed. The socket is flatter than it will be as the child grows and eventually develops into a cup shaped socket that will surround the ball at the top of the arm bone.
This is the glenohumeral joint. In order to stimulate appropriate growth of bone and cartilage in the area, there has to be normal nerve supply and normal movement of the bones in and near the shoulder joint. Glenohumeral dysplasia is simply abnormal development of this joint. This complication can result in a deformed joint that does not function as it should, and creates a high risk of shoulder dislocations.
Another complicating factor is a domino effect. Brachial plexus injury causes an imbalance in the strength of the various muscle groups that apply force to the shoulder and arm. The imbalance causes abnormal movement; abnormal movement causes abnormal wear patterns, and that in turn leads to the development of osteoarthritis in the joint. Physicians who have cared for patients with brachial plexus injuries into adulthood report that almost all of these patients will have significant osteoarthritis-related problems as they age.
Scoliosis is an abnormal curvature of the spine. A child who has neurological impairment from cerebral palsy, or more rarely from brachial plexus injuries, may also have an imbalance in muscular strength. This can cause abnormal forces being placed on the child’s spine during growth or development, leading to scoliosis. Severe scoliosis may require surgery.
Balance and coordination are complicated functions of your body. Brachial plexus injuries that impair sensation, proprioception, muscle movement, strength and biomechanics can have a significant and negative impact on your child’s balance and coordination.
Bimanual dexterity is the ability to coordinate the movement and function of both hands. Many jobs, from an assembly line worker in a Detroit automobile plant to a secretary who needs to type a hundred words a minute, require the simultaneous use of both hands in rapid, coordinated movements in order to perform the job quickly and efficiently. Any reduction in this dexterity can result in a comparable reduction in your child’s ability to find and keep a job. Occupational therapy is critical to maximizing your child’s dexterity. But please remember that the degree of success of the therapy is dependent not only on the location and severity of the brachial plexus injury, but how much effort you and your child invest in making the therapy successful.
You and your child will face many psychological challenges, and it is important to understand that your entire family will be affected. The combination of physical impairments and disabilities from a birth injury, with the unfortunately probable social effects of those injuries on your child’s relationships with other children, and perhaps adults, can and will affect your child’s development. Recognizing this early on will enable you to plan for and meet the challenges.
Infants and toddlers frequently do well from a psychological point of view because they aren’t yet capable of perceiving or understanding the differences between them and their peers. As they grow and gain an understanding of the fact they have limitations that their friends and other children do not, helping to create and maintain good self image and self esteem becomes very important to your child’s development. These challenges are likely to be especially difficult in the pre-teen and teen years. Collectively, we have found it is critical to find some activity at which your child can excel. Doing so will not cure all problems your child will have as he or she grows up, but it will certainly help.
The diaphragm is the large muscle that separates the chest from the abdomen. The nerve supply to the diaphragm comes from the phrenic nerve that arises from the 3rd, 4th and 5th cervical nerve roots. The phrenic nerve can also be damaged at the same time as the brachial plexus is stretched due to excessive force being applied by the doctor delivering the baby. Damage to phrenic nerve weakens the diaphragm which can result in decreased lung capacity and reduced endurance while exercising.
Horner Syndrome (also called Bernard-Horner syndrome and oculosympathetic palsy) generally refers to a drooping eyelid on the side affected by the brachial plexus injury. Other indications are a slight elevation of the lower lid, constricted pupil, a perceptible lag when the eye dilates. Sometimes there will be an impression that the eye is sunk in, or decreased sweating on the affected side of the face. A child with this condition may sometimes wind up with different colored eyes, because the unequal nerve stimulation interferes with the body’s process for coloring a growing child’s eyes.
This illustration provides an example of some of the physical effects of the Horner Syndrome as well as some of the physical effects of an Erb’s Palsy injury.