The effects of a brachial plexus injury may present themselves in a variety of ways. In addition to the asymmetry issues at the shoulder, scapula, and trunk, the child may have decreased function at the elbow, forearm, wrist and hand. There are different postures of the arm that a child with a brachial plexus injury may have. Two common distal postures are the "Waiter’s Tip" and the "Erb’s Engram."

This posture, usually seen during infancy, is the result of very weak or absent elbow flexors and extensors, as well as weak or absent wrist extensors, and finger flexor and extensors. Here, the arm is positioned in full extension, and the wrist is fully flexed. The baby does not have enough muscle strength to hold the elbow flexed, or the wrist up to grasp objects. The arm often looks like it is hanging, so these children are often susceptible to shoulder subluxations.

To provide shoulder support in order to encourage function down the arm, the shoulder and scapula can be therapeutically taped in position so that the arm is anchored safely in the joint. Distally, this weakness can cause the finger flexors to get tight as they may get overstretched from crossing over a tight wrist. To prevent tightness, it is a good idea to stretch the wrist while opening the fingers to prevent tightness.

Activities to encourage passive stretching of the wrist include weight-bearing activities by positioning the child’s palm flat on the floor. If the child cannot maintain the passive positioning unassisted, options include: a wrist cock-up splint to position the wrist up during the day for function, and a full functional hand splint for night to extend the wrist and position the fingers to prevent tightness.

 This posture manifests when the child has weak biceps (elbow flexor and prime supinator) and weak triceps (elbow extensors). If these muscles are weak, the child may tend to position the arm in elbow flexion with pronation, as there is not full muscle potential to fully bend or straighten the arm. If the child continues to carry the arm flexed, without the ability to fully flex or extend, weight-bearing also becomes less likely. Weight-bearing is most crucial for integrity and alignment at all of the joints of the arm. It is also vitally important for the sequence of normal development, and it is a necessary part of the rehabilitation process for overall strengthening, and providing sensory feedback into the arm. Because the engram is a result of weak muscles, the joint integrity is compromised.

The engram can make a child susceptible to contractures. To prevent contractures, the child should be positioned with the elbow extended and the forearm neutral to participate in weight-bearing. Activities to encourage weight-bearing include: wheelbarrow walking, animal imitations, playing Twister, and crawling over and under many obstacles.

If the child is unable to maintain extension of the elbow, an air cast may be beneficial. This is a long arm pillow tube that resembles an "arm swimmie". It gets wrapped around the arm, and inflated until the compressed air straightens the arm. To prevent contractures, the child may benefit from a night-time full elbow extension splint with the forearm positioned in full supination, and the thumb included to prevent torque pronation forces in the splint.

If there are significant contractures the child may benefit from drop-out serial casting, where the arm would be casted in the same position as the splint mentioned above. However, this would necessitate frequent cast changes and stretching twice weekly, with the hope of quickly and fully straightening the arm. There are also some nice splinting systems on the market that are adjustable, and less cumbersome than a cast. A dynamic splint such as Dynasplint will provide tension on the elbow to gradually straighten it. An Ultraflex brace is a customized dynamic splint that can provide dynamic tension to the elbow in extension, the forearm in supination, and even the wrist and fingers if necessary.

A weight-bearing splint is commonly used to position the wrist, hand, and elbow in full extension for crawling and weight-bearing activities. The Benik Corporation has cosmetically pleasing wrist cock-up splints that resemble roller blade gloves; they are cooler and comfortable. If the child is rejecting splint wear, this may be a better option. To encourage supination, a supinator strap can be placed on any wrist cock-up splint or functional splint to position the forearm in a more neutral posture for holding a lunch tray or throwing a basketball.

Your child’s therapist should be able to fabricate the splints or order the splints as deemed appropriate. If not, you may have to access a therapist at a local Pediatric Hospital.

There are also some non-traditional options to help your child. Other therapies which may be used (for children who meet the criteria of age, body size and weight) include NMES and TES. Neuromuscular Stimulation (NMES) will help with strengthening of the muscles. This is a muscle stimulator that is placed over the motor points of muscles that have intact nerves to elicit a visible muscle contraction for facilitating active movement. Threshold Electrical Stimulation (TES) provides electrical stimulation into the muscle at a very low sensory threshold. It is worn at night (while the child is sleeping), and its goal is to achieve muscle growth and bulk. In order to participate in any of these programs, it is crucial for the therapist to be trained in these specialized techniques for children.

There are also surgical options available that may improve active motion of the elbow and the wrist. Options should be discussed with a surgeon who specializes in brachial plexus injuries.

Regardless of the type of arm posturing, it is always essential to keep the arm as limber as possible with a good stretching routine, and encouragement to incorporate the arm in bi-manual activities as much as possible. Along with these techniques, consistent communication with a multi-disciplinary brachial plexus health-care team, (Neurologist, Surgeons, Therapists, and Social Worker) is advised to provide you with the most current treatment approaches for brachial plexus injuries.

 Deborah Humpl has been an Occupational Therapist for nine and a half years working in Pediatric Rehabilitation. She is currently working at the Children’s Hospital of Philadelphia in the Outpatient Department, and is a team member in the Brachial Plexus Clinic.