AbstractsBiology & Animal Science

Cerebral palsy (CP) is a developmental disorder of movement and posture that occurs due to damage to the developing nervous system. The current standard of care for gait treatments includes stretching, night splinting, serial casting, physical therapy, medication, botulinum toxin injections and orthopedic surgeries. In some cases therapists may visit homes of patients to prescribe exercises but only for few hours a week. The equipment used for therapy is large and stationary requiring the patients to visit clinics. Motor learning therapies require repetitive voluntary movements and it may be difficult to achieve this during the limited outpatient hours available. Wearable sensors that trigger interactive feedback can be easily portable and used at home enabling repetitive movements as per the patients’ schedule. They reduce personnel and equipment demand and require minimum clinical supervision. Auditory feedback has been helpful in gait retraining in past studies. A portable, musical device could have therapeutic effect by promoting gait retraining. Here, we describe a prototype of a heel-strike real-time feedback system that has been developed as part of the dissertation. It records the number of heel strikes during gait and also promotes them through real time auditory feedback. The prototype was tested with healthy children and children having CP. The accuracy in detecting heel strikes in case of healthy children was 97.8% (S.D. = 5.541) and when tested with children having CP it was 96.78% (S.D. = 5.243). The device is lightweight and does not affect the maximum force with which neurologically impaired children strike their feet during walking. The heel strike timing detected by the device was compared to the time at which heel strike was detected by a force plate. Based on statistical analysis, the difference between heel strike detected by a force plate and the heel-strike detected by the device was on an average 14 ms. In some trials, there was minimal delay showed by the device compared to a force plate, in detecting a heel strike. Children found the sound feedback provided by the device to be appealing. On an average it took the subjects 1.455 more iteration (95% CI of 0.503 to 2.406) to learn a movement pattern without sound than when the sound is turned on. Sound feedback thus helped them to learn new movement patterns in lesser time. With auditory feedback, the performance accuracy was higher by 21.599 percentage points on an average (95% CI of 12.319 to 30.878). The functional prototype was tested with young children having CP and it could detect heel strikes in children who occasionally walked on their toes and pronated. It could be extended to use with children having walking disorders due to other neurological disorders such as autism, developmental delays, and stroke. These studies inform research and development of a future product that uses interactive sound to motive motor learning gains, might be used in the home environment, and might become a commercial product.