What to expect from PRP injection for knee cartilage injury

A cartilage injury can involve the smooth joint surface or the cartilage and bone beneath it. PRP is prepared from a sample of your own blood and placed near the painful knee area. It is intended to support the local healing environment; it does not replace missing cartilage or reshape a damaged joint surface. The clinician may use ultrasound or another imaging method to guide placement.

Pain can be more noticeable for a short period after the injection, and improvement is usually assessed over time rather than immediately. The outlook depends on the location and size of the injury, alignment, activity demands, and other knee findings.

Before treatment, discuss medicines, bleeding problems, allergies, infection, and any recent procedure. Follow the clinic's instructions about eating, drinking, and medicines; do not stop prescribed treatment without medical advice. Arrange transport if your knee feels weak or uncomfortable afterward.

For the first phase, protect the knee from impact and heavy loading as directed. Gentle movement may be encouraged, while running, jumping, deep squats, and strenuous lifting may need to wait. Rehabilitation commonly progresses from mobility and muscle activation to controlled strengthening, then activity-specific loading. Keep the follow-up appointment so pain, movement, and function can guide the next step.

Contact the treating clinic promptly if pain or swelling is worsening rather than settling, the injection site becomes increasingly red or hot, or you develop drainage or fever. Seek urgent care for severe pain with a rapidly enlarging knee, new numbness or weakness, or trouble breathing. A locked knee, inability to bear weight, or a new injury also warrants timely assessment.

Ask what type of cartilage injury is present, what improvement would count as meaningful, how much weight you may place on the leg, when physiotherapy should begin, and which pain medicines are suitable for you. Also ask whether imaging, another treatment, or a review of knee alignment is needed if symptoms persist.