Defining Treatment Outcomes and Genetic Architecture in Idiopathic Toe Walking*

Velocity (m/s) will be assessed during walking in the gait lab.

Stride Length (m) will be assessed during walking in the gait lab.

Kinematics as calculated from the reflective markers placed on the skin during the computerized gait analysis will allow for the computation of knee, ankle and foot kinematics during walking.

Knee Kinematics (measured in degrees): Knee angle at IC, knee extension at midstance, peak knee flexion in swing.

Ankle kinematics (measured in degrees): Ankle angle at IC, ankle angle at midstance, angle range of 3rd rocker, average ankle angle in stance, average ankle angle in swing.

Multisegment Foot Motion (measured in degrees): ankle complex flexion, rotation, 2)midfoot flexion, rotation and 3) hallux varus and flexion rotation.

Walk-DMC is a measure of motor control which is calculated from the dynamic muscle activity from five muscles (rectus femoris, medial and lateral hamstrings, tibialis anterior and gastrocnemius, bilaterally)

Ankle kinetics: peak plantarflexion moment and power absorption at loading response, power generation at terminal stance will be calculated from the force plates and gait kinematics during the walking gait analysis.

Quantitative assessment of toe walking will be obtained with the in-shoe system the NURVV/RUN. The NURVV/RUN calculates the percentage of foot contact time spent on the rearfoot, midfoot and forefoot.

Daily functional musculoskeletal health will be assessed with the Pediatric Outcomes Data Collection Instrument, a questionnaire that contains 108 questions in seven domains including four functional assessment areas: upper extremity functioning, transfers and basic mobility, sports and physical function, and comfort/pain. Items have different weights, with possible scores range from three (often, sometimes, rarely or never) to five (none, very mild, moderate, severe, very severe). For most items a lower score indicates higher functioning or a more positive quality of life.

Dorsiflexion with and without knee flexion, popliteal angle are measured with a goniometer and measured in degrees

A hand-held dynamometer (HHD) will be used to assess quantitative muscle strength, via a "make test" for ankle dorsiflexors/plantarflexors, and foot inverters/everters, bilaterally.

This novel tool designed for screening out children who toe walk for other reasons such as neurogenic, neuromuscular, or traumatic. If any questions are answered as yes, the principal investigator will review to determine whether a diagnosis of idiopathic toe walking is appropriate.

Selective Voluntary Motor Control Scale is a simple clinical measure of the ability to selectively control the muscles. Selective motor control of the hip, knee, ankle, subtalar, and toe joints will be assessed using the Selective Voluntary Motor Control tool. A total of 10 points is possible for each side with higher numbers indicating more selective control.

The coactivation tool utilizes electromyographic activity during two lower extremity activities to determine whether there is coactivation between the gastrocnemius and the quadriceps during resistive knee extension bilaterally. Abnormalities in the muscle activation pattern may be an indication of a diagnosis other than idiopathic toe walking.

The subtests of Bilateral Coordination and Balance which form the Body Coordination composite score will be used ascertain coordination of children with ITW relative to age-matched norms to help characterize the population and determine if coordination influences outcome. Higher scores indicate better balance and bilateral coordination.

Whole Genome Sequencing will be done on the participant and both biological parents (if possible) to determine if the patient and their parents have any genetic abnormalities in genes that may be associated with toe walking and to determine if the cohort as a whole have potential new genes that may be indicative of toe walking.