Elastographic Assessment of Gastrocnemius Muscle Structure in Children With Idiopathic Toe Walking

Fatih Sultan Mehmet Training and Research Hospital46 enrolled

Overview

Idiopathic toe walking (ITW) is a gait pattern characterized by the absence of heel strike during the stance phase and incomplete foot contact with the ground. After excluding neurological, neuromuscular, and orthopedic causes such as cerebral palsy, neuropathies, myopathies, and spinal dysraphism, the diagnosis of ITW can be established. Although alterations in muscle histology and architecture have been reported in children with ITW, radiological evaluation of the musculoskeletal system remains limited. Shear Wave Elastography (SWE) is a non-invasive, objective, and cost-effective imaging technique that quantitatively assesses tissue stiffness by measuring shear wave velocity and elasticity. The present study aims to evaluate gastrocnemius muscle and Achilles tendon elasticity in children with ITW compared with age-matched healthy controls. By combining SWE measurements with clinical assessments-including ankle dorsiflexion range of motion, Toe Walking Severity Scale, Foot Posture Index, and a functionality questionnaire-we aim to better characterize the musculoskeletal alterations associated with ITW.

In some children, the inability to perform heel strike may lead to toe walking. Toe walking can occur due to a variety of conditions, including cerebral palsy, spina bifida, muscular dystrophies, limb-length discrepancies, and autism spectrum disorders. When no underlying medical cause is identified, the diagnosis of idiopathic toe walking (ITW) is made. ITW is a diagnosis of exclusion. The etiology of ITW remains unclear. A positive family history of toe walking has been frequently reported, suggesting a potential genetic component. Sensory integration deficits have also been proposed as a contributing factor. Muscle biopsy studies have shown an increased proportion of type I fibers in children with ITW compared to typically developing peers. Toe walking leads to remodeling of the muscle-tendon unit. A study using ultrasonography (US), isokinetic dynamometry, and surface electromyography have demonstrated that the gastrocnemius (GC) muscle and its fascicles are longer and the Achilles tendon is shorter in children with ITW compared to healthy controls. Rehabilitation strategies such as stretching, strengthening, and spasticity management aim to improve the biomechanical properties of the muscle. Investigating biomechanical characteristics, including muscle stiffness, is essential for understanding musculoskeletal adaptations. Non-invasive techniques are particularly preferred in the pediatric population. Shear-Wave Elastography (SWE) is a non-invasive, cost-effective, and objective method for evaluating tissue stiffness in vivo, with promising clinical applications in the musculoskeletal system. While SWE has been applied in pediatric neuromuscular conditions, data on musculoskeletal imaging in children with ITW remain limited. Few studies have evaluated this population using ultrasonography and none have directly compared ITW children with healthy controls using SWE. Evaluating differences between children with ITW and their typically developing peers may enhance understanding of this poorly understood gait pattern and support the development of more effective treatment approaches. The aim of this study is to assess the structure of the medial gastrocnemius muscle and Achilles tendon in children with ITW using SWE, comparing the results with a healthy control group. This approach will allow comprehensive evaluation of clinical parameters and musculoskeletal characteristics in this children.

Eligibility

Sex: ALLMin age: 4 YearsMax age: 12 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: Children aged 4 to 12 years with a bilateral idiopathic toe walking pattern Absence of neurological, orthopedic, or psychiatric conditions that could explain the toe walking gait pattern (e.g., cerebral palsy, myopathies, autism spectrum disorders, developmental disorders, neuropathies) Healthy volunteers matched for age and sex (for control group) Child and parent/guardian who were willing to participate in the study and provided written informed consent. \- Exclusion Criteria:Presence of neurological, orthopedic, or psychiatric conditions that could explain the toe walking gait pattern (e.g., cerebral palsy, myopathies, autism spectrum disorders, developmental disorders, neuropathies) \-

Outcomes

Primary Outcomes

Elastography measurements (kPa) of the gastrocnemius muscle and Achilles tendon in children with idiopathic toe walking compared to healthy controls

The gastrocnemius is a biarticular muscle, and its stiffness may be influenced by ankle dorsiflexion and plantarflexion. In the present study, all measurements were performed with the child in the prone position. In children with idiopathic toe walking, both lower extremities were evaluated with the knees extended and the feet hanging off the examination table. Tissue elasticity (kPa) was measured from the medial gastrocnemius and Achilles tendon in three different ankle positions: neutral, passive dorsiflexion, and passive plantarflexion. For each region of interest, five measurements were obtained and averaged.Gastrocnemius muscle and Achilles tendon length was also recorded. For the control group, the same measurements were performed on the dominant lower extremity. The dominant leg was determined by asking the child which foot they would use to kick a ball.