Is there a relationship between muscle-tendon properties and a variety of functional tasks in children with spastic cerebral palsy?

Christian Schranz; Annika Kruse; Markus Tilp; Martin Svehlik

doi:10.1016/j.gaitpost.2021.01.009

Is there a relationship between muscle-tendon properties and a variety of functional tasks in children with spastic cerebral palsy?

Gait Posture. 2021 Mar:85:14-19. doi: 10.1016/j.gaitpost.2021.01.009. Epub 2021 Jan 14.

Authors

Christian Schranz¹, Annika Kruse², Markus Tilp³, Martin Svehlik⁴

Affiliations

¹ College of Health Professions, Medical University of South Carolina, 77 President St, Charleston, SC, USA.
² Institute of Human Movement Science, Sport and Health, Department of Biomechanics, Training and Movement Science, University of Graz, Mozartgasse 14, Graz, A-8010, Austria. Electronic address: annika.kruse@uni-graz.at.
³ Institute of Human Movement Science, Sport and Health, Department of Biomechanics, Training and Movement Science, University of Graz, Mozartgasse 14, Graz, A-8010, Austria.
⁴ Department of Orthopaedics and Trauma, Medical University of Graz, Auenbruggerplatz 5, Graz, A-8036, Austria.

PMID: 33487525
DOI: 10.1016/j.gaitpost.2021.01.009

Abstract

Background: Cerebral palsy (CP) is the most common motor and movement disability in childhood. The mechano-morphological alterations of the spastic muscle itself as well as the functional limitations in CP are well documented. However, the relationship between muscle tendon properties and functional tests in CP remains unknown.

Research question: The aim of this study was to explore the relationship between spastic muscle mechano-morphological properties and functional performance in children with CP.

Methods: This study included retrospective data from 22 children with spastic cerebral palsy with a mean age of 12.8 years (19 GMFCS I/3 GMFC II, 15 male/7 female, 8 unilateral involved/14 bilateral). Mechano-morphological properties of gastrocnemius (GM) and Achilles tendon (AT) were correlated with a variety of functional measures, maximal isometric strength, the Muscle Power Sprint test (MPST), 6-minute walk test (6MWT) and 3D-gait analysis using the Pearson Coefficient.

Results: Muscle-tendon properties were normalized to remove anthropometric dimensions because of strong associations with anthropometric data. Higher isometric muscle strength was related to longer normalized GM fascicle lengths (r = 0.67, p < 0.01). The distance reached in the 6MWT positively correlated with normalized GM fascicle lengths (r = 0.61, p < 0.01). Higher AT stiffness was associated with faster performance in the MPST (r = 0.77, p < 0.01). Finally, there was an association between ankle power and both longer normalized AT length and shorter muscle belly (r = 0.60 and r = 0.54, p < 0.01).

Significance: The findings of this study give more insight into the function specific adaptations of a spastic muscle-tendon unit. While walking, assessed through the 6MWT, was related to normalized gastrocnemius fascicle length, sprint performance was associated with an increased AT stiffness. These results provide a better understanding of the relationship between functional tasks and spastic muscle-tendon properties, which offers potential for improved and targeted interventions in CP.

Trial registration: ClinicalTrials.gov NCT02319122.

Keywords: Cerebral palsy; Functional fitness; Muscle alteration; Spasticity; Walking.

MeSH terms

Achilles Tendon / physiopathology
Ankle Joint / physiopathology
Anthropometry
Cerebral Palsy / pathology
Cerebral Palsy / physiopathology*
Child
Female
Gait Analysis
Humans
Male
Muscle Spasticity / pathology
Muscle Spasticity / physiopathology
Muscle, Skeletal / pathology
Muscle, Skeletal / physiopathology*
Retrospective Studies
Task Performance and Analysis
Tendons / physiopathology*
Walk Test
Walking / physiology

Associated data

ClinicalTrials.gov/NCT02319122