Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.
Definition of Knee ligaments
Medically reviewed by Dr. Otari Nergadze, Neurosurgeon | Updated: January 2026
Knee ligaments: Ligaments are strong, elastic bands of tissue that connect bone to bone. They provide strength and stability to the joint.
Four ligaments connect the femur (the bone in the thigh) with the tibia (the larger bone in the lower leg):
- The medial collateral ligament (MCL) provides stability to the inner (medial) aspect of the knee.
- The lateral collateral ligament (LCL) provides stability to the outer (lateral) aspect of the knee.
- The anterior cruciate ligament (ACL), in the center of the knee, limits rotation and the forward movement of the tibia.
- The posterior cruciate ligament (PCL), also in the center of the knee, limits backward movement of the tibia.
Other ligaments are part of the knee capsule, which is a protective, fiber-like structure that wraps around the knee joint. Inside the capsule, the joint is lined with a thin, soft tissue, called synovium.