Provides warmth, compression, and knee joint stability for injuries; including patello-femoral pain and moderate ligament tears. May also provide appropriate support for a meniscus tear. The X-Factor knee brace stabilizes the knee joint area, helping to prevent further injury. It contains an infrapatellar buttress to support the patella and help improve patellar tracking. Medial and lateral spiral stays provide additional stability to the ligaments of the knee joint. Measure the circumference of the knee 3 in above the patella for the correct size.