Related Experiment Video
Updated: Oct 3, 2026
Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination
Published on: July 7, 2016
Architecture of the medial gastrocnemius in children with spastic diplegia
A P Shortland1, C A Harris, M Gough
1One Small Step Gait Laboratory, Guy's Hospital, London, UK. adam.shortland@gstt.sthames.nhs.uk
Insights
In children with spastic diplegia, medial gastrocnemius muscle contracture is not primarily caused by reduced fascicle length. Findings suggest aponeuroses shortness may explain fixed muscle shortness in this condition.
Area of Science:
- Biomedical Engineering
- Musculoskeletal Research
- Pediatric Neurology
Background:
- Spastic diplegia is a common form of cerebral palsy affecting muscle tone and movement.
- Medial gastrocnemius muscle contracture is frequently observed in ambulant children with spastic diplegia.
- The structural origins of muscle contracture in this population remain incompletely understood.
Purpose of the Study:
- To investigate muscle architectural properties, specifically fascicle length and deep fascicle angle, of the medial gastrocnemius in children with spastic diplegia.
- To compare these architectural variables with those of normally developing children and adults.
- To determine if reduced fascicle length contributes to the fixed shortness observed in medial gastrocnemii of children with spastic diplegia.
Main Methods:
- Ultrasound imaging was used to measure medial gastrocnemius fascicle length and deep fascicle angle.
- Measurements were taken at various ankle joint positions with the knee extended.
- The study included normally developing adults, normally developing children, and children with spastic diplegia.
Main Results:
- Fascicle length and deep fascicle angle were similar between normally developing adults and children.
- No significant difference in fascicle length was found between normally developing children and those with spastic diplegia.
- Deep fascicle angles were significantly reduced in the clinical group at a specific ankle joint angle, but this was attributed to resting muscle length and lacked clinical significance.
Conclusions:
- Reduced muscle fascicle length does not appear to be the primary cause of fixed shortness in the medial gastrocnemii of ambulant children with spastic diplegia.
- The study suggests that shortness of the aponeuroses, potentially related to reduced muscle fascicle diameter, may offer a better explanation for muscle contracture in this population.
- Further research is needed to elucidate the precise structural origins of muscle contracture in spastic diplegia.
Abstract:
Ultrasound images were obtained of the medial gastrocnemius at different ankle joint positions with the knee extended. Fascicle length and deep fascicle angle were measured in five normally developing adults (mean age 33 years, age range 24 to 36 years) and in five normally developing children (mean age 7.8 years, age range 7 to 11 years), and in seven children with spastic diplegia (mean age 10 years, age range 6 to 13 years). These architectural variables were similar in the groups of normally developing adults and children. Importantly, no statistical difference could be found between the normally developing children and those with diplegia for fascicle length. Deep fascicle angles were reduced significantly in the clinical group at a particular ankle joint angle but not at the resting angles. The difference in deep fascicle angles is explained as a function of resting muscle length and is not attributed any clinical importance. Our results do not explain the structural origin of muscle contracture explicitly. However, they do indicate that most of the fixed shortness in the medial gastrocnemii of ambulant children with spastic diplegia is not due to reduced muscle fascicle length. We suggest that muscle contracture may be better explained in terms of shortness of the aponeuroses of pennate muscles, such as the medial gastrocnemius, through reduced muscle fascicle diameter.
Related Concept Videos
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.
01:23Muscles 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 to...
01:16Bones of the Lower Limb: Femur and Patella
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 fascia...