There are four main ligaments in the knee: anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL). Any one of these ligaments may be partially or completely torn due to trauma (pivot, forceful hit to the knee). Physiotherapy is effective in reducing pain and improving strength in both partially torn ligaments and following surgical repair. To reduce pain therapeutic modalities such as ultrasound and laser can be used. A physiotherapist will provide an exercise program to improve control of the knee stabilizers and education to prevent re-injury.