Below is information for a handout I wrote when working in a clinic. It contains basic information about sprains/strains of the knee
The knee is a complex structure consisting of four strong ligaments – the Posterior Cruciate Ligament (PCL), Anterior Cruciate Ligament (ACL), Lateral Collateral Ligament (LCL), and the Medial Collateral Ligament (MCL) – cartilage known as meniscus, and a number of tendons the cross over the knee to allow for knee flexion and extension-most notably the patellar/quadriceps tendons.
The knee is the most injured joint of the body, with most injuries being a sprain to one of the four ligaments. Commonly knee injuries occur as a result of participating in sports. Other causes can be slips, trips, and motor vehicle accidents. Knee strains and sprains are caused by direct trauma.
Tips to Prevent Injury
Unfortunately, knee injuries caused by direct trauma, for example a football player getting tackled at the knees, are unpreventable. However, one way to minimize the risk of a strain, sprain, is to properly warm up before participating in sporting activity. Often a person will get injured because they are inexperienced or casual participants in sport and are not conditioned for the rigors of sport.
Exercise is also important as it will help retain flexibility in the knee and keep the muscles and tendons surrounding the knee strong to provide stability.
If you have a history of knee injuries then wearing a protective brace or taping before participating in physical activity is a good idea.
Immediate treatment for a mild strain/sprain injury should focus on reducing swelling and pain with a combination of anti-inflammatory medication and following the R.I.C.E model:
Rest – take a break from activities that may aggravate the injury
Ice – Ice the injury for 15-20 minutes on and off for about 2 hours to keep swelling down
Compression – keep pressure on the injury by using a wrap in order to push swelling away from the injury
Elevation – Elevate the leg above the level of the heart by lying down and supporting the leg with pillows or books to prevent pooling of blood and to keep swelling down
Strengthening exercises should be included once swelling has decreased, usually about 3-4 days.