PROJECT SUMMARY Rotator cuff tears are the most common tendon injury observed in adults. The risk for rotator cuff injury significantly increases with age, affecting approximately 25% of the population older than 60 years and 60% of those over the age of 80 years old. Currently, the standard of care for most rotator cuff tears is arthroscopic surgical repair, with nearly 500,000 of these procedures performed annually in the United States and direct costs of over $7 billion per year. Rotator cuff repair (RCR) outcomes are dependent upon successful rehabilitation, with proper healing and functional recovery of the rotator cuff following surgical repair substantially decreasing the high incidence of retears. Healing and recovery after RCR are dependent upon strict adherence to a delicate rehabilitation process during which the repaired tendon must be unloaded by carefully performing controlled movements that do not inadvertently activate contraction of the shoulder muscles. The complexity of these movements can make it challenging for patients to maintain compliance during rehabilitation, and thus require extensive guidance on movements during rehabilitation following RCR to reduce the risk of repair failure and retear. There exists a clear need for the development of technologies that provide continuous, real-time guidance to patients during rehabilitation following RCR and enable the continuous and efficient integration of valuable patient-specific data into the design of custom rehabilitation programs. This Phase II SBIR application will build upon promising outcomes from Active4D’s funded SBIR Phase I project which resulted in the successful design of a wearable biofeedback system – the MyoGuard system - and demonstrated the accuracy and reproducibility of its continuous monitoring and biofeedback of muscle activity and joint angle. The goal of the MyoGuard system is to expedite patient return to normal activity and prevent retears following rotator cuff repair by enabling increased patient compliance with rehabilitation exercises and improving the customization of care. This Phase II SBIR project will focus on preparations for the commercialization of the MyoGuard system. In Aim 1, we will optimize the design of the MyoGuard system for scalable manufacturing and increase the accessibility of the MyoGuard phone application to better facilitate independent use of the device. In Aim 2, we will conduct human subjects research to obtain normative activity data and evaluate human factors, including ease of use and patient compliance. The successful completion of this SBIR Phase II project will provide strong baseline evidence to support decision-making and the design for our future Phase I clinical trial that will test the efficacy of the MyoGuard system in reducing complications, particularly retears, following rotator cuff repair. These key data will ultimately allow us to seek 510K FDA regulatory approval and support rapid commercialization and de...