How effective is PRP injection for knee cartilage injury?

Knee cartilage injury can range from a surface defect to damage involving deeper joint tissue. PRP is prepared from your own blood and injected into the knee or around a targeted area, depending on the clinical plan. It is intended to influence local inflammation and symptoms; it is not a replacement layer for missing cartilage. A locked knee, catching, swelling after activity or pain with weight-bearing can point to a mechanical problem that an injection alone may not address. Examination and imaging help determine whether the injury is suitable for non-surgical care.

Discuss the cartilage location, size and effect on joint movement before treatment. A rehabilitation plan may include range-of-motion work, quadriceps and hip strengthening, balance exercises and a gradual return to impact. Your clinician can explain whether the injection is intended for pain control, improved exercise tolerance or another specific goal. Keep a record of swelling, locking and activity tolerance so progress can be judged by function rather than a single good or bad day. Read more about [PRP Injection](/treatments/non-surgical-orthopedics/prp-injection/).

Seek prompt assessment if the knee becomes locked, cannot bear weight, swells suddenly after an injury, gives way repeatedly, or develops severe pain with a hot, red joint. Following an injection, worsening redness, drainage, fever or rapidly increasing swelling needs urgent contact with the treating service.

Where is the cartilage damage and does it affect joint mechanics? What result are we aiming for with PRP? What rehabilitation will follow it? Could locking or recurrent swelling change the treatment plan?