The knee joint, the largest in the body, enables standing, movement, and balance through a complex interplay of bones, cartilage, and ligaments.
Anatomy and Function
The knee connects your thigh bone (femur) to your shin bone (tibia), with the kneecap (patella) acting as a protective element. This intricate structure allows for a wide range of motion.
- Bones: The femur, tibia, and patella are the primary bones forming the knee joint.
- Cartilage: Cartilage, such as the meniscus, cushions the bones and facilitates smooth movement. The menisci act as shock absorbers.
- Ligaments: Several ligaments provide crucial stability:
- Medial Collateral Ligament (MCL): Prevents the knee from bending inward.
- Lateral Collateral Ligament (LCL): Prevents the knee from bending outward.
- Anterior Cruciate Ligament (ACL): Prevents the tibia from sliding forward under the femur.
- Posterior Cruciate Ligament (PCL): Prevents the tibia from sliding backward under the femur.
These components work together to allow for flexion (bending), extension (straightening), and some rotation of the leg.
Movement and Balance
The knee's ability to support weight and facilitate movement is essential for daily activities. The coordinated actions of muscles surrounding the joint—quadriceps (extensors) and hamstrings (flexors)—control the knee's range of motion and stability. Proper alignment and balance depend on the integrated function of these muscles, ligaments, and bones. The reference states that the knee "helps you stand, move and keep your balance," highlighting its crucial role in locomotion and postural control.
