Knee instability is the sensation of the knee giving out and is usually the result of an injury to a ligament. Injuries to one or more ligaments can lead to the two sides of the joint not being held tightly enough in position. Usually, symptoms of instability occur with twisting or side-to-side movements. This may occur in sports activities, or may occur with simple tasks such as twisting your knee to get in and out of a car. It is also possible for people to experience instability symptoms with injuries that cause knee pain. Nonsurgical treatments for knee instability can include physical therapy to strengthen the muscles around the knee joint and knee braces to better support the knee joint. Often, however, surgical treatment may be needed to restore the normal structure of the knee joint.
Knee Instability and Treatment | MedStar Health