Exploration for Injury to an Infant’s Brachial Plexus

Indications

• Obstetric brachial plexus palsy (OBPP) has a high percentage of injuries that achieve complete recovery spontaneously, yet this does not occur in roughly 30% of patients.

• Usually stretching injury of the brachial plexus components. Preganglionic avulsion injury is less common. Mixed injuries are fairly common.

• For OBPP, the typical lesion in infants is a neuroma- in-continuity, incomplete stretching that allows for some axon fibers to grow through and reach distal targets.

• Typical signs and symptoms are relevant to the roots and nerves involved in the injury.

• Upper brachial plexus injury, which usually involves C5-6 roots (a.k.a. C5-C6, upper trunk palsy, Duchenne-Erb syndrome) is characterized by lost or reduced shoulder abduction and elbow flexion, while hand function is preserved, and usually with significant inability to lift hand to mouth against gravity by 5 months of age. This type of injury has good spontaneous recovery.

• Lower-type obstetric brachial plexus palsy (aka C8-T1, lower trunk palsy, Dejerine-Klumpke syndrome) is rarely seen in OBPP. It also can be associated with Horner’s syndrome and is characterized by complete hand and wrist palsy.

• Complete obstetric brachial plexus palsy (C5-T1 palsy) paralyzes the shoulder, elbow, and hand. As in lower trunk palsy, sometimes Bernard-Horner syndrome is associated.

• Usually the natural course of OBPP will get to plateau in recovery after 9 months of age with significant residual motor deficit.