Associations between muscle morphology and spasticity in children with spastic cerebral palsy

• Published in: European journal of paediatric neurology 2023-05, Vol.44, p.1-8
• Main Authors: Peeters, Nicky, Hanssen, Britta, Bar-On, Lynn, De Groote, Friedl, De Beukelaer, Nathalie, Coremans, Marjan, Van den Broeck, Christine, Dan, Bernard, Van Campenhout, Anja, Desloovere, Kaat
• Format: Article
• Language: English
• Subjects: Cerebral palsy; Cerebral Palsy - complications; Cerebral Palsy - diagnostic imaging; Child; Children; Humans; Muscle morphology; Muscle Spasticity - complications; Muscle Spasticity - etiology; Muscle, Skeletal - diagnostic imaging; Spasticity; Ultrasonography; Ultrasound
• ISSN: 1090-3798; 1532-2130
• DOI: 10.1016/j.ejpn.2023.01.007

Due to the heterogeneous clinical presentation of spastic cerebral palsy (SCP), which makes spasticity treatment challenging, more insight into the complex interaction between spasticity and altered muscle morphology is warranted. We studied associations between spasticity and muscle morphology and compared muscle morphology between commonly observed spasticity patterns (i.e. different muscle activation patterns during passive stretches). Spasticity and muscle morphology of the medial gastrocnemius (MG) and semitendinosus (ST) were defined in 74 children with SCP (median age 8 years 2 months, GMFCS I/II/III: 31/25/18, bilateral/unilateral: 46/27). Using an instrumented assessment, spasticity was quantified as the difference in muscle activation recorded during passive stretches at low and high velocities and was classified in mixed length-/velocity-dependent or pure velocity-dependent activation patterns. Three-dimensional freehand ultrasound was used to assess muscle morphology (volume and length) and echogenicity intensity (as a proxy for muscle quality). Spearman correlations and Mann-Whitney-U tests defined associations and group differences, respectively. A moderate negative association (r = −0.624, p