Introduction

The severity of neonatal brachial plexus palsy (NBPP) ranges from mild nerve stretch injuries with rapid recovery to nerve root avulsions with minimal recovery. However, a significant number of NBPP patients do not regain full arm function, so the principles of rehabilitation remain constant: maintain range of motion at all upper extremity joints, encourage strengthening as much as possible, prevent compensatory movement patterns, and, most importantly, promote normal development of function.

Initial evaluation and intervention

Babies with NBPP are typically characterized by arm weakness in the immediate neonatal period due to trauma to the fetal brachial plexus at some point prior to completion of delivery. Initial evaluation for NBPP should take place as soon as possible after delivery when the infant is medically stable. History should include details about the mother’s pregnancy, labor and delivery with particular attention to maternal diabetes or gestational diabetes, hypertension, method of delivery, difficulties during labor and delivery, and Apgar scores. Details of the infant’s neonatal course should also be noted, including respiratory status and feeding ability.

Physical examination of the infant should include the following: general inspection, weight, length, head circumference and growth percentiles, examination of both legs including hips, examination of both arms, observation of respiratory pattern and movement of the chest, observation for any signs of pain at rest or while the infant is being examined. Particular attention should be paid to examining the eyes for Horner’s sign (ptosis, meiosis, and anhydrosis; Figure 12.1), and to the resting position of the neck in the supine and prone resting positions for torticollis and during active and passive movement. Is neck strength normal for the patient’s age? In addition, examination of the affected arm should include observation in the resting position for classic postures of NBPP (eg, Waiter’s tip; Figure 12.2), testing passive and active ranges of motion, recording lengths and circumferences of all segments of the upper extremity, and estimation of motor power of the arm and hand.

Figure 12.1 Horner’s sign.

Figure 12.2 “Waiter’s tip” posture (left arm).

Is the child normal aside from the affected arm, or are there other problems such as abnormal tone in the trunk or other extremities, poor head control for age, weak suck or uncoordinated suck and swallow?

At the end of the examination, the following questions should be answered and recorded (Table 12.1):

Table 12.1 Examination record for patients with neonatal brachial plexus palsy

Figure 12.3 Plagiocephaly.

If the initial evaluation is performed in an older infant or child, gross and fine motor function and language skills should be observed to determine if further detailed testing is warranted.

Initial rehabilitation management

Following the initial evaluation, a treatment plan should be made that specifies both short- and long-term goals. Even if the infant may require nerve repair/reconstruction, occupational and/or physical therapy should be initiated to optimize outcomes of surgical intervention. The infant who develops early contractures will not recover function as well as the child who has no contractures. The therapist must formulate treatment planning strategies by considering the upper extremity with regard to the motor power of each muscle, potential safety precautions, functional recovery, and the long-term psychosocial effects of NBPP. Proximal stability or core strength is crucial and underlies good distal mobility as well as fine motor and gross motor coordination. It is absolutely essential for the therapist to understand the anatomy of the brachial plexus and the extent of stretch to the nerves in order to develop appropriate short- and long-terms goals of the treatment plan. Therapy evaluation and treatment can and should begin as early as day-1 of life, particularly in cases where the infant is medically stable.

A common presentation for the infant with NBPP (primarily affecting the upper trunk) is a weak or limp arm positioned in an internal rotation with the shoulder adducted, elbow extended, forearm pronated, and fingers and wrist flexed (Figure 12.2). As the nerves of the brachial plexus regenerate, motor function recovers. The course of recovery for an infant with an upper trunk (Erb’s) palsy includes slight shoulder flexion (often derived from the pectoralis muscle), enough to flex the shoulder to allow gravity to seemingly flex the elbow. Gradually, the infant learns to extend the wrist (Steindler effect) or flex the fingers to aid and/or augment elbow flexion (Figure 12.4). The focus of therapy with infants at this point is to facilitate shoulder flexion, particularly by abduction with external rotation at the shoulder, and elbow flexion against gravity. The timing for nerve repair/reconstruction varies within the surgical community, ranging from 3 months to 9 months of age. Most practitioners agree that recovery of shoulder flexion and abduction followed by elbow flexion against gravity beginning by <3 months of age obviates the need for surgical intervention. If clinical, electrodiagnostic, and radiographic data are consistent with nerve root avulsion injury, nerve repair/reconstruction may be recommended as early as 3 months of age.

Figure 12.4 Using wrist extension to facilitate elbow flexion in right arm (Steindler effect).

The most important goal of therapy for NBPP patients is maintenance of soft tissue and joint flexibility. Passive range-of-motion exercises are critical and must be taught to the parents/caregivers to be performed routinely at home.¹ These exercises can be performed safely and effectively to gently stretch the relevant muscles and joint structures to avoid development of contractures (resulting from excessive contraction of the functioning muscles that are not counterbalanced by the paretic muscles).

Children with NBPP risk developing skeletal deformities of the trunk and affected extremity due to poor bone growth associated with weakness of certain muscles, unopposed activities of other muscles, or muscle imbalance (Figure 12.5).² Poor bone growth is a direct result of decreased weight-bearing coupled with lack of muscle tension upon areas of the bone that contribute to bone growth.

Figure 12.5 Musculoskeletal deformities (right arms).

Infants

Motor training should begin as early as possible. The purpose of motor training is to stimulate activity in denervated muscles, to enable muscles to be activated as soon as nerve regeneration has taken place, to prevent or minimize soft tissue contractures, and to minimize ineffective substitution movements. Motor training should continue for as long as recovery is still occurring.

In the newborn period, the initial evaluation should ascertain the presence of clavicle or humeral fractures, respiratory problems, or other difficulties. In one study, 1 in 11 newborns with a clavicle fracture also had NBPP.³ In addition to evaluation of arm function, assessment should also be made of oral motor skills and feeding, head control, and head positioning. In an unpublished study, 43% of children under 6 months of age with NBPP also had torticollis.⁴ Feeding difficulties may be due to birth asphyxia, facial nerve injury, or breathing problems, including phrenic nerve injury.⁵

In healthy newborns with brachial plexus palsy, it is important to educate the parents on passive range-of-motion exercises for all muscle groups. These exercises should be performed at every diaper change. Additionally, parents should be educated regarding the need for “tummy time” at each diaper change to promote symmetrical head rotation and positioning. Torticollis is an abnormal head posture including ipsilateral tilt, contralateral rotation and translation,⁶ and it is the third most common pediatric orthopedic diagnosis in childhood.⁷ Persistent torticollis may lead to plagiocephaly and facial asymmetry; deformational plagiocephaly can be appreciated as early at 6 weeks of age with a preexisting diagnosis of torticollis.⁸ The major cause of deformational plagiocephaly is limited head mobility in early infancy secondary to cervical imbalance.⁹ For infants with torticollis, parents should be encouraged to vary the position of the infant’s head during play, feeding, and sleeping. Use of positioning wedges may be helpful. Home programs using neck stretches to address tightness of the sternocleidomastoid muscle may be required for some infants and should be taught to families by appropriately trained therapists.

In some instances, a newborn will require a hand/elbow splint prior to discharge from the hospital. The indications for a hand splint are tightness of the finger joints and/or significant atrophy of the thenar eminence. If Horner’s sign is present, significant atrophy of the thenar eminence is usually present and indicates the need for a resting hand splint. The preferable position for a resting hand splint would be the intrinsic plus position (Figure 12.6). In the intrinsic plus position, the metacarpophalangeal joints are flexed at 60–70 degrees, the interphalangeal joints are fully extended, and the thumb is in partial abduction and flexion or opposed to the extended interphalangeal joint of the index finger. The wrist is held in extension at 10 degrees less than maximal.

Figure 12.6 Preferred “intrinsic plus” position for resting hand splint.

An elbow flexion splint may be indicated if there is subluxation. Extreme hyperextension of the elbow reflects absent biceps muscle activity in the context of intact triceps muscle activity, causing muscle imbalance. Passive range-of-motion exercises for elbow flexion should be performed with careful attention to position of the forearm in supination or pronation (whichever position prevents subluxation from occurring).

A newborn should not demonstrate pain during range-of-motion exercises. If pain is present, re-evaluation for skeletal injury should be undertaken. Sequelae include sensory alterations associated with motor weakness. Sensory changes can include absence of or impaired sensation in all or part of the extremity, based upon which nerves were involved during the initial stretch. With altered sensation, hyperesthesia and allodynia is expressed in the newborn with “fussiness.” Desensitization can relieve the symptoms and can be achieved by the use of firm touch versus light touch, the use of infant massage, a variety of texture inputs from fabrics, or vibratory input from infant toys.

When a clavicle or humerus fracture is present, the arm should be immobilized using a sling with the shoulder adducted and internally rotated and elbow flexed at 90 degrees so that the arm rests upon the infant’s chest for 3–6 weeks. The newborn should be lifted by scooping the newborn under the buttocks with one hand and under the head with the other versus lifting the infant under the axillae. Teaching a family to dress the involved extremity first and undress it last may also prove beneficial in reducing unnecessary movement of the involved extremity during the healing phase of the fractured area(s).

The NBPP therapy session begins with passive range-of-motion exercises. Once the infant’s muscles are stretched and prepared for activity, elicitation of active range-of-motion exercises can be encouraged by stroking, tapping, or vibrating the muscle belly. Vibration can be used to elicit triceps or elbow extension, deltoids or shoulder flexors/abductors, or finger/wrist extensors. Elicitation can occur in gravity-eliminated positions, progressing to antigravity positions, and ultimately in weight-bearing positions developmentally appropriate for the patient. Vibration/stroking can be used to elicit biceps contraction or elbow flexion to achieve movement patterns of hand to face or mouth, elbow extension such as batting at toys overhead, and wrist extension patterns to facilitate reaching for toys. The therapy sessions should include interventions that facilitate the patient’s current level of generalized development. The impact of the weak arm upon developmental milestones should be a major focus of every therapy session.

Infants with NBPP learn quickly to adapt to their development with a unilateral bias. Progression toward symmetrical development begins with learning to roll prone to supine and back to both right and left sides. A similar approach can be applied when the child moves from supine to sitting position. Once a child has learned to transition into sitting, progression to 4-point positioning is appropriate. The strength and coordination required to sustain and/or reach from the point position is a precursor to crawling. Some infants master the “commando crawl” while others will not learn to crawl and will progress directly from sitting to walking. Therapy techniques to facilitate crawling include the use of elbow supports/splints, weight-bearing hand and/or wrist splints, shoulder support splinting or taping techniques, or use of positioning techniques⁹ combined with vibration or, in some situations, neuromuscular electrical stimulation. Protective reactions in the affected extremity are often delayed or weak, yet they must be a focus of therapy. A small therapy ball can be used to develop forward protective reactions in prone and sitting positions.

With the increasing popularity of the “back to sleep” campaign, prone activities and neck rotation skills must be encouraged to promote maximal function of the recovering muscles and to prevent plagiocephaly. Tightness or contractures in the sternocleidomastoid muscle can inhibit arm movement. Release of contracture of the sternocleidomastoid muscle through stretching techniques, use of inhibitory or facilitative Kinesio-taping (KMS, LLC, Albuquerque, NM), and dynamic weight-shifting activities can maximize development of proximal stability within the trunk and shoulder area. Flexibility throughout the neck and trunk is imperative for optimal shoulder range of motion.

Symmetrical movement patterns facilitate motor planning and proper development. A motor pattern program should be initiated to avoid the inadvertent establishment of compensatory motor patterns. Neglect of the involved extremity can occur, so the affected arm should be brought into the child’s visual field as much as possible. Encourage the child to explore the involved hand at midline with the other hand and, if appropriate, encourage mouthing of the involved hand. Precautions should be taken as some children may bite the affected hand. Toys such as play mats, overhead play gyms, wrist rattles, toys that make noise or vibrate, and light-weight rattles with small diameter handles may be used at home to encourage bilateral integration.