Reduced Cross-Sectional Muscle Growth Six Months after Botulinum Toxin Type-A Injection in Children with Spastic Cerebral Palsy

• Published in: Toxins Vol. 14; no. 2; p. 139
• Main Authors: De Beukelaer, Nathalie, Weide, Guido, Huyghe, Ester, Vandekerckhove, Ines, Hanssen, Britta, Peeters, Nicky, Uytterhoeven, Julie, Deschrevel, Jorieke, Maes, Karen, Corvelyn, Marlies, Costamagna, Domiziana, Gayan-Ramirez, Ghislaine, Van Campenhout, Anja, Desloovere, Kaat
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14.02.2022; MDPI
• Subjects: 3D freehand ultrasound; Age; botulinum neurotoxin type-A; Botulinum toxin; Botulinum Toxins, Type A - therapeutic use; Cerebral palsy; Cerebral Palsy - drug therapy; Child; Child, Preschool; Children; Female; Humans; Injection; Injections, Intramuscular; Male; Microscopic analysis; Morphology; muscle growth rate; Muscle Spasticity - drug therapy; Muscle, Skeletal - drug effects; Muscle, Skeletal - growth & development; Muscles; Neuromuscular Agents - therapeutic use; Neurotoxins; Paralysis; Physical therapy; spastic cerebral palsy; Spasticity; Toxins; Treatment Outcome; muscle growth rate; spastic cerebral palsy; 3D freehand ultrasound; botulinum neurotoxin type-A
• ISSN: 2072-6651; 2072-6651
• DOI: 10.3390/toxins14020139

Botulinum Neurotoxin type-A (BoNT-A) injections are widely used as first-line spasticity treatment in spastic cerebral palsy (SCP). Despite improved clinical outcomes, concerns regarding harmful effects on muscle morphology have been raised. Yet, the risk of initiating BoNT-A to reduce muscle growth remains unclear. This study investigated medial gastrocnemius (MG) morphological muscle growth in children with SCP ( = 26, median age of 5.2 years (3.5)), assessed by 3D-freehand ultrasound prior to and six months post-BoNT-A injections. Post-BoNT-A MG muscle growth of BoNT-A naive children ( = 11) was compared to (a) muscle growth of children who remained BoNT-A naive after six months ( = 11) and (b) post-BoNT-A follow-up data of children with a history of BoNT-A treatment ( = 15). Six months after initiating BoNT-A injection, 17% decrease in mid-belly cross-sectional area normalized to skeletal growth and 5% increase in echo-intensity were illustrated. These muscle outcomes were only significantly altered when compared with children who remained BoNT-A naive (+4% and -3%, respectively, < 0.01). Muscle length growth persevered over time. This study showed reduced cross-sectional growth post-BoNT-A treatment suggesting that re-injections should be postponed at least beyond six months. Future research should extend follow-up periods investigating muscle recovery in the long-term and should include microscopic analysis.