Cerebral Palsy (CP) presents motor impairments as one of its main symptoms, such as the equinus gait pattern. There is a portable electrical stimulator available in the market called the Walkaide® which aims to stimulate the anterior tibial muscle. However, due to shortening and contractures, the triceps surae muscle suffers a decrease in its ability to move, resulting in hyperactivation of the anterior tibial muscle. Stimulating the triceps surae muscle can provide the necessary force for improving gait biomechanics, generating an increase in propulsion during the terminal support phase, range of motion, speed, and stride length. Unfortunately, the Walkaide® is not accessible in low- and middle-income countries like Brazil due to its cost.

To evaluate the immediate effects of a prototype portable electrical stimulator designed to activate the gastrocnemius muscle in children with Cerebral Palsy.

Three children with right-side unilateral CP (two females aged 9 and 13 years old, and one male aged 9 years old) participated in this prototype study. Plantar pressures were evaluated in a semi-static posture and during walking on the MPS Platform with and without the use of electrical stimulation on the gastrocnemius muscle. The pressures in different areas of the foot and the arch index were analyzed before and during the use of the electrical stimulator in the two conditions mentioned above.

The use of electrical stimulator led to an improvement in the plantar distribution in both affected and non-affected lower limbs in static and dynamic conditions, as observed in the three children with CP evaluated. In the static condition with the stimulator, there was greater weight bearing posteriorly to the right, an increase in the contact surface, and an improvement in the arch index compared to the condition without the stimulator. In the dynamic condition, there was an increase in the contact surface of the right foot with the device, and the weight distribution was more symmetrical when compared to not using the device.

The use of electrical stimulator on the gastrocnemius muscle has a great potential for improving the distribution of plantar pressures, which can enable children with unilateral CP to distribute their weight to the heel. Therefore, it is believed that with time, children may show an improvement in their gait pattern.

The use of the electrical stimulator may lead to improvements in plantar pressures, allowing children with unilateral CP to discharge weight posteriorly. This could potentially replace the use of standardized orthoses, resulting in aesthetic and practical benefits. Additionally, it promotes the development of a national equipment with lower costs of production.