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Updated: Dec 4, 2025
Author Spotlight: Decellularization-Based Quantification of Skeletal Muscle Fatty Infiltration
Published on: June 9, 2023
Intramuscular fat in children with unilateral cerebral palsy
Arkiev D'Souza1, Bart Bolsterlee2, Ann Lancaster3
1Neuroscience Research Australia (NeuRA), 139 Barker St, Randwick, 2031, NSW, Australia; School of Medical Sciences, University of New South Wales (UNSW), Randwick, NSW, Australia.
Insights
Children with cerebral palsy have more intramuscular fat than typically developing children, potentially contributing to muscle contractures. This study found higher fat proportions in cerebral palsy muscles but no direct link to contracture severity.
Area of Science:
- Biomedical Engineering
- Orthopedics
- Pediatric Neurology
Background:
- Muscle contractures are common in children with cerebral palsy (CP).
- The underlying mechanisms of contracture development in CP are not fully understood.
- Elevated intramuscular fat, due to its stiffness, is hypothesized to contribute to muscle contractures.
Purpose of the Study:
- To investigate the role of intramuscular fat in the development of muscle contractures in children with cerebral palsy.
- To compare the quantity and distribution of intramuscular fat in muscles of children with and without CP.
Main Methods:
- A cross-sectional study involving 20 children with unilateral spastic cerebral palsy and ankle contractures and 20 typically developing children.
- Magnetic resonance imaging (mDixon) was used to obtain detailed images of the medial gastrocnemius muscles.
- Intramuscular fat fraction was quantified and the distribution of fat was analyzed.
Main Results:
- Children with cerebral palsy exhibited significantly higher mean intramuscular fat fractions (11.4% in more-affected, 6.9% in less-affected muscles) compared to typically developing children (4.7%).
- Statistically significant, though small, regional differences in fat distribution were observed.
- No clear relationship was found between the intramuscular fat fraction and the severity of ankle contractures.
Conclusions:
- Children with cerebral palsy have increased intramuscular fat proportions in their lower limb muscles compared to typically developing peers.
- While higher fat content is present, it does not show a direct correlation with the degree of ankle dorsiflexion limitation or contracture severity in this cohort.
Background:
Many children with cerebral palsy develop muscle contractures. The mechanisms of contracture are not well understood. We investigated the possibility that, because fat is stiffer than passive muscle, elevated intramuscular fat contributes to contracture. In this cross-sectional study, we compared the quantity and distribution of intramuscular fat in muscles from typically developing children and children with cerebral palsy who have contractures.
Methods:
mDixon magnetic resonance images were obtained from the legs of 20 ambulant children with unilateral spastic cerebral palsy who had ankle contractures (mean age 11 SD 3 years, 13 male, mean moderate level contracture) and 20 typically developing children (mean age 11 SD 4 years, 13 male). The images were analyzed to quantify the intramuscular fat fraction of the medial gastrocnemius muscles. The amount and distribution of intramuscular fat were compared between muscles of children with cerebral palsy and typically developing children.
Findings:
In typically developing children, the medial gastrocnemius muscles had a mean intramuscular fat fraction of 4.7% (SD 1.6%). In children with cerebral palsy, the mean intramuscular fat fractions in the more- and less-affected medial gastrocnemius muscle were 11.4% (8.1%) and 6.9% (3.4%) respectively. There were small but statistically significant regional differences in the distribution of intramuscular fat. There was no evidence of a relationship between intramuscular fat fraction and severity of contracture.
Interpretation:
Children with cerebral palsy have higher proportions of intramuscular fat than typically developing children. There is no clear relationship between intramuscular fat fraction and dorsiflexion range of motion in children with cerebral palsy.
