Knee Osteoarthritis !
Knee osteoarthritis is the gradual wear of the cartilage lining the knee joint; it causes pain, stiffness and sometimes swelling.
Updated 2026-10-23
Structures involved
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In biochemistry
In histology
- Cartilage: hyaline, elastic, fibrocartilage
- Synovial joints: capsule, synovial membrane and articular cartilage
In the clinical exam
- Joint examination: inspection, palpation and range of motion
- Meniscal tests: McMurray and Apley
- Knee effusion: patellar tap and bulge sign
- Inspection of gait and posture (orthopedic)
Why it happens
What it is
Gradual wear of the articular cartilage of the knee joint.
Symptoms and signs
- Activity-related pain
- Stiffness after rest, usually lasting less than about 30 minutes
- Swelling
- Reduced range of motion
Diagnosis
- Clinical
- History and exam
- Imaging
- X-rays show joint-space narrowing; MRI shows cartilage detail
Treatment
- Conservative
- Physical therapy, weight management, activity changes, medicines or injections for pain.
- Surgical
- Knee replacement for advanced disease.
Drugs for this condition
Related conditions
Educational information, not medical advice. For any symptom, see a health professional.
Sources: Knee Osteoarthritis (StatPearls (NCBI Bookshelf), 2024).
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