Knee Joint

Hinge under load

How does the knee Joint work?

The largest joint in the body: femur, tibia and kneecap held together by ligaments and cushioned by cartilage and two menisci.

Parts

Cartilage gives a smooth, low-friction surface; the menisci spread load; the ACL and PCL stop the bones sliding apart.

Loading

Joint cartilage is nourished by movement. Regular activity and leg strength support knee function.

When to get help

Swelling after a twist, locking, or the knee giving way are worth getting checked.

Evidence & sources

• Exercise is strongly recommended for people with knee osteoarthritis. Evidence: strong. Known: Guideline based on systematic reviews of trials. Unknown: The best type and amount varies; a clinician or physical therapist can tailor it. Source: American College of Rheumatology, Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee (2019).

Connected topics

• Tendons & Ligaments
• Strength Training
• Walking
• Vitamin C

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.