Knee Injuries and Disorders
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt or diseased, you have knee problems. Knee problems can cause pain and difficulty walking.
Knee problems are very common, and they occur in people of all ages. Knee problems can interfere with many things, from participation in sports to simply getting up from a chair and walking. This can have a big impact on your life.
The most common disease affecting the knee is osteoarthritis. The cartilage in the knee gradually wears away, causing pain and swelling.
Injuries to ligaments and tendons also cause knee problems. A common injury is to the anterior cruciate ligament (ACL). You usually injure your ACL by a sudden twisting motion. ACL and other knee injuries are common sports injuries.
Treatment of knee problems depends on the cause. In some cases your doctor may recommend knee replacement.
NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- ACL Injury: Diagnosis and Treatment · Mayo Foundation for Medical Education and Research
- Direct Arthrography · Radiological Society of North America
- Iliotibial Band Syndrome (For Parents) · Nemours Foundation
- Knee Arthroscopy · American Academy of Orthopaedic Surgeons
- Knee MRI · Radiological Society of North America
- X-Ray Exam: Knee (For Parents) · Nemours Foundation
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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