Related Experiment Video
Updated: Nov 25, 2025
Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination
Published on: July 7, 2016
Gastrocnemius Medialis Muscle Geometry and Extensibility in Typically Developing Children and Children With Spastic
Guido Weide1,2,3, Peter A Huijing1, Lynn Bar-On2,3
1Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.
Insights
Children with spastic paresis (SP) exhibit altered gastrocnemius medialis (GM) muscle morphology and tendon growth, impacting muscle extensibility. These changes are linked to age and body mass, unlike in typically developing children.
Area of Science:
- Biomedical Engineering
- Orthopedics
- Pediatric Neurology
Background:
- Children with spastic paresis (SP) often display reduced ankle range of motion, linked to triceps surae (TS) muscle inflexibility.
- Limited understanding exists regarding the specific morphological muscle characteristics in children with SP.
Purpose of the Study:
- To compare gastrocnemius medialis (GM) muscle geometry and extensibility in children with SP versus typically developing (TD) children.
- To investigate the relationship between GM morphology and its extensibility in both groups.
Main Methods:
- Utilized 3D ultrasound imaging to assess GM muscle geometry in SP and TD children under varying ankle flexion moments (0 and 4 Nm).
- Quantified GM extensibility as the change in muscle length between 0 and 4 Nm moments.
- Analyzed correlations between anthropometric variables, muscle morphology, and extensibility.
Main Results:
- No significant differences in anthropometric variables or GM extensibility were found between SP and TD groups.
- While GM muscle volume correlated with body mass in both groups, the relationship differed significantly (TD slope > SP slope).
- In TD children, GM fascicle length correlated with age, lower leg length, and body mass; this correlation was absent in SP children.
- Tendinous structure elongation in SP children exceeded that in TD children and even lower leg length increases.
- In SP children, increased body mass, height, muscle volume, physiological cross-sectional area, and tendon length were negatively associated with GM extensibility.
Conclusions:
- Children with SP show distinct patterns of GM muscle and tendon morphology compared to TD children, with elongated tendons being a key feature.
- Morphological characteristics, particularly physiological cross-sectional area and tendon length, are positively associated with age and negatively associated with GM extensibility in children with SP.
- These findings highlight unique adaptations in muscle and tendon structures in pediatric spastic paresis that influence joint mobility.
Abstract:
Gait of children with spastic paresis (SP) is frequently characterized by a reduced ankle range of motion, presumably due to reduced extensibility of the triceps surae (TS) muscle. Little is known about how morphological muscle characteristics in SP children are affected. The aim of this study was to compare gastrocnemius medialis (GM) muscle geometry and extensibility in children with SP with those of typically developing (TD) children and assess how GM morphology is related to its extensibility. Thirteen children with SP, of which 10 with a diagnosis of spastic cerebral palsy and three with SP of unknown etiology (mean age 9.7 ± 2.1 years; GMFCS: I-III), and 14 TD children (mean age 9.3 ± 1.7 years) took part in this study. GM geometry was assessed using 3D ultrasound imaging at 0 and 4 Nm externally imposed dorsal flexion ankle moments. GM extensibility was defined as its absolute length change between the externally applied 0 and 4 Nm moments. Anthropometric variables and GM extensibility did not differ between the SP and TD groups. While in both groups, GM muscle volume correlated with body mass, the slope of the regression line in TD was substantially higher than that in SP (TD = 3.3 ml/kg; SP = 1.3 ml/kg, p < 0.01). In TD, GM fascicle length increased with age, lower leg length and body mass, whereas in SP children, fascicle length did not correlate with any of these variables. However, the increase in GM physiological cross-sectional area as a function of body mass did not differ between SP and TD children. Increases in lengths of tendinous structures in children with SP exceeded those observed in TD children (TD = 0.85 cm/cm; SP = 1.16 cm/cm, p < 0.01) and even exceeded lower-leg length increases. In addition, only for children with SP, body mass (r = -0.61), height (r = -0.66), muscle volume (r = - 0.66), physiological cross-sectional area (r = - 0.59), and tendon length (r = -0.68) showed a negative association with GM extensibility. Such negative associations were not found for TD children. In conclusion, physiological cross-sectional area and length of the tendinous structures are positively associated with age and negatively associated with extensibility in children with SP.
Related Concept Videos
01:23Muscles that Move the Leg
Anterior Compartment
The quadriceps femoris, the most visible muscle of the anterior compartment, is integral for leg extension and thigh flexion. It is formed by merging four distinct muscles — the vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris. The quadriceps tendon, a shared tendon of the four quadriceps muscles, is affixed...
01:28Muscles of the Leg that Move the Foot and Toes
Anterior Compartment
The anterior compartment includes muscles that contribute to the dorsiflexion of the foot. This compartment houses the tibialis anterior, extensor hallucis longus, and extensor digitorum longus muscles....
01:20Muscles that Move the Thigh
Three other significant muscles are the gluteus maximus, gluteus medius, and gluteus minimus. The gluteus maximus originates from the posterior surface of the ilium, sacrum, and coccyx, and the thoracolumbar...
01:16Bones of the Lower Limb: Femur and Patella