Soft-stop knee brace for rehabilitation from ligament injuries: Design and pilot trial

Ligaments within the human knee are commonly torn or injured as a result of sports that involve sharp direction changes, pivoting and landing. For this reason, athletes are often side-lined from their respective sports for up to 18 months after injury to rehabilitate. As part of the rehabilitation process, knee braces are often prescribed in an attempt to decrease the recovery period of the injured individual by restraining and minimizing the motion at the knee. However, the true efficacy of knee bracing is yet to be fully evaluated as studies show mixed results to whether braces actually decrease the rehabilitation period for patients. This paper describes the design and pilot trials of a simple but novel knee brace design that aims to actively aid the rehabilitation of the knee from ligament injuries, primarily the anterior cruciate ligament (ACL). The newly developed knee brace uses an angle locking mechanism with dampers to control both the range of motion of the knee joint and the resistance applied to the knee joint at the limits of extension. Using finite element analysis, these dampers were designed help build muscle strength during everyday use of the knee brace and to reduce the ‘jarring effect’ which causes significant pain and risk to patients using current knee brace designs. Through providing these features, this new knee brace design has the potential to help improve the extent and speed of recovery for ACL impaired patients.