A cross-sectional design study will be carried out to explore the morphological muscle properties and alterations in muscle composition on a macroscopic level in children with spastic cerebral palsy (CP). Muscle composition will be assessed using quantitative Magnetic Resonance Imaging (qMRI) and shear wave elastography (SWE), while macroscopic muscle size properties will be evaluated through 'Three-dimensional freehand ultrasound (3DfUS).
Children (boys/girls) with congenital brain lesion, confirmed with neuro-imaging such as MRI
At high-risk for CP or diagnosed spastic type of CP
(Suspected) Gross Motor Function Classification Scale (GMFCS) Level I-III
Uni or bilateral involvement
Presence of dyskinesia or ataxia
Severe co-morbidities (cognitive problems)
BTX treatment in the gastrocnemius in the past 10 months
Previous surgery at the investigated muscles.