A Novel Non-Invasive Knee Joint Monitor with Built-in Real-time Patellar Tracking for Improved Joint Rehabilitation and Monitoring

Abstract

Active-duty military personnel are more susceptible to knee injuries requiring surgery than the civilian population. There is no efficient way to track rehabilitation for military personnel due to shortages of physical therapists. It was reported that active-duty personnel have a knee injury rate of 25 per 1,000 soldiers which exceeds the civilian rate. A key concern of rehabilitation in knee injuries is properly aligning the patella. Existing methods of patella tracking are expensive and not made for dynamic tracking. SmartSleeve is a device allowing for real-time patella tracking and monitoring knee temperature to alert physicians and patients of impending deep vein thromboembolism, a life-threatening condition. We aimed to determine an efficient way to track the patella in real-time to support rehabilitation plans we used a LilyPad Temperature Sensor attached to an Arduino Uno Board to measure knee temperature patella movement tracking with Adafruit Force Sensitive Resistor. We validated the temperature sensor through controlled testing and its sensitivities did not lie between the thresholds to detect a DVT. We developed a novel wearable knee sleeve to track the temperature and patella movement that is expected to shorten rehabilitation time. In the future, additional sensors, such as flex and circumferential elastomeric resistive stretch sensors for measuring knee effusion and kinematics, are planned for implementation into the SmartSleeve for post-surgery knee monitoring ultimately decreasing the return to duty time-frame.