Use of botulinum toxin type A in the management of neonatal brachial plexus palsy

Abstract

Objective: To evaluate functional outcomes and the impact on surgical interventions after the use of botulinum neurotoxin type A (BoNT-A) for muscle imbalance, cocontractions, or contractures with neonatal brachial plexus palsy.

Design: A retrospective cohort study.

Setting: A brachial plexus center in a tertiary children's hospital.

Participants: Fifty-nine patients with neonatal brachial plexus palsy (75 injection procedures, 91 muscles and/or muscle groups) received BoNT-A injections (mean age at injection, 36.2 months; range, 6-123 months; 31 boys; 30 right-sided injuries, 28 left-sided injuries, 1 bilateral injury).

Methods: Data collected retrospectively from medical records, from procedure notes and clinic visits before BoNT-A use, at ≤6 months follow-up (BoNT-A active [BA]) and at ≥7 months follow-up (BoNT-A not active [BNA]) included demographics, injection indication, side, and site(s), previous surgical history, occupational therapy and/or physical therapy plan, and outcome measurements.

Main outcome measurements: Outcomes assessed before and after injections included active and passive range of motion, Mallet and Toronto scores, parent comments about arm function, preinjection surgical considerations, and postinjection surgical history.

Results: Injection procedures included 51 to shoulder internal rotators, 15 triceps, 15 pronator teres, 9 biceps, and 1 flexor carpi ulnaris. Active and passive shoulder external rotation (SER) range of motion improved after shoulder internal rotator injections (P = .0003 and P = .002, respectively), as did Mallet scores with BA; the latter were sustained with BNA. Surgical intervention was averted, modified, or deferred after BoNT-A in 45% (n = 20) under surgical consideration before BoNT-A. Active elbow flexion improved in 67% (P = .005), sustained BNA (P = .004) after triceps injections; 2 of 7 patients averted surgery. Active supination improved with BA (P = .002), with gains sustained BNA (P = .016). Passive elbow extension improved after biceps injections by an average 17° (P = .004) BA, although not sustained BNA.

Conclusions: BoNT-A is an effective adjunct to therapy and surgery in managing muscle imbalance, cocontractions, and contractures in neonatal brachial plexus palsy. Use of BoNT-A can result in averting, modifying, or deferring surgical interventions in a number of affected children.