These knee braces are designed to help treat injuries to the Anterior Cruciate Ligament (ACL) and Posterior Cruciate Ligament (PCL). Knee braces for ACL and PCL injuries should be lightweight but strong, and be able to protect the injured knee ligament by restricting range of motion. ACL and PCL knee braces can be worn after injury (prior to surgery), after surgery and during aggressive activities such as sports to protect the knee after healing has occurred.