Indications and effects of botulinum toxin A for obstetric brachial plexus injury: a systematic literature review

Abstract

AIM To give an overview of indications for the use of botulinum toxin A (BoNT-A) treatment for children with obstetric brachial plexus injury (OBPI), and to present the best available evidence of the effectiveness of this treatment.METHOD Searches were performed in Cinahl, Cochrane Library, Embase, PubMed, and Web of Science, using the keywords 'botulinum' and 'plexus', to identify articles reporting on the use of BoNT-A as a treatment for children with OBPI. Studies found through the references of related articles were also selected.RESULTS Ten full-text papers and six congress abstracts were included, involving 343 children.Four groups of indications could be identified: internal rotation ⁄ adduction contracture of the shoulder, limited active elbow flexion, limited active elbow extension, and pronation contracture of the lower arm. Overall, positive results were reported for all except the indication for limited active elbow extension. However, only one study was comparative in nature; all others were classified as having a low level of evidence. There was a large variation in outcome measures.INTERPRETATION To provide better evidence for the already partly promising results of BoNT-A treatment for children with OBPI, multicentre randomized controlled trials are needed.Obstetric brachial plexus injury (OBPI) is commonly caused by traction during delivery. A recent study on its incidence showed a decrease over time in hospitals in the USA from 1.7 per 1000 live births in 1997 to 1.3 per 1000 in 2003. 1 A higher, and somewhat increasing, incidence has been found in various European studies, ranging from 3 per 1000 in Norway 2 and 3.3 per 1000 in Sweden 3 to 4.6 per 1000 live births in a Dutch university hospital. 4 Explanations for these different trends are probably related to the percentage of Caesarean sections performed, the incidence of infants with a high birthweight, the multiple-birth rates, the rates of preterm labour induction, and different systems for reporting OBPI. Conservative management starts during the first weeks of life, the main aim of the treatment being to prevent contractures and joint deformities. At an older age, the aim of exercise therapy is to improve bimanual, school, and daily self-care activities. The decision to perform neurosurgical repair of the brachial plexus depends on the severity of the plexus injury. Avulsion is a clear indication for early neurosurgical reconstruction. 5 In the case of a rupture, microsurgical repair is performed when the infant is between 3 and 9 months of age. The time range is a consequence of non-conforming supporting evidence for the predictive value of the antigravity function of the biceps brachii muscle. Complete recovery rates vary from 66% to 92%, 4,6-10 depending on the criteria used to define complete recovery.Children with delayed complete neurological recovery and those with incomplete neurological recovery, sustaining muscle denervation, and, therefore, muscle imbalance and cocontraction, are at high risk of problems such as contractures,...

External Rotation Predicts Outcomes After Closed Glenohumeral Joint Reduction With Botulinum Toxin Type A in Brachial Plexus Birth Palsy

“…With regards to children with BPBP and nonspastic contractures, BTX-A has been shown to enhance the ability of muscle to passively stretch 30 and magnify active motion through inhibition of imbalanced antagonistic muscles. 31,32 Some authors believe BTX-A has the additional ability to alter cortical patterning. 33,34 This may explain why some series demonstrate functional improvements beyond the established 3 to 4 months of therapeutic efficacy of BTX-A.…”

Strategies for the Abnormal Co-Contraction of Internal Rotators of the Shoulder in Children with Obstetrical Brachial Plexus Palsy

“…The most commonly injected muscle in previous reports was the pectoralis major, and in varying combination with the latissimus dorsi, teres major, and subscapularis. The active range of shoulder abduction/external rotation increased after BTX-A treatment in most of the studies [3] . We applied BTX-A treatment for abnormal co-contraction of the latissimus dorsi/teres major complex and subscapularis confirmed by the surface EMG.…”

“…Although most patients with OBPP recover spontaneously in the first 2 months, up to 35% are left with varying degrees of shoulder weakness, contracture, or joint deformity [2] . Even after neuro-reconstructive surgery, children with incomplete recovery often have abnormal motor performance [3] . The upper trunk of the brachial plexus (C5 and C6) is most commonly affected in OBPP [3,4] .…”

“…Even after neuro-reconstructive surgery, children with incomplete recovery often have abnormal motor performance [3] . The upper trunk of the brachial plexus (C5 and C6) is most commonly affected in OBPP [3,4] . Paresis of the deltoid, supraspinatus, infraspinatus, and teres minor, which are innervated by the upper trunk, results in poor performance of the shoulder abduction/external rotation.…”

“…Recently, an increasing number of reports on the treatment of botulinum neurotoxin A (BTX-A) for OBPP have been published [3] . BTX-A is a reversible neurotoxin.…”