How long does PRP injection take to work for knee osteoarthritis?

Knee osteoarthritis involves changes in the joint tissues that can cause pain, stiffness and reduced confidence with activity. PRP is injected into the knee to influence the local joint environment; it does not reverse established joint changes instantly. Some people notice post-injection soreness before any improvement, so early discomfort does not by itself show whether the treatment will help.

Response is influenced by the extent of joint change, alignment, muscle strength, weight-bearing demands and other sources of pain. Useful progress may look like easier walking, stairs or rising from a chair, even if some stiffness remains. A planned review helps distinguish a gradual response from a different knee problem.

Follow the injection aftercare plan and return to activity in stages. Physiotherapy can address knee movement, thigh and hip strength and load management. Choose tolerable exercise such as clinician-approved cycling, walking or strengthening, and avoid sudden increases in hills, impact or deep bending. Note morning stiffness, walking tolerance and swelling from week to week.

Contact the clinic for increasing redness, warmth, drainage, fever or pain that is not settling after the injection. Seek urgent assessment for a locked knee, sudden inability to bear weight, severe swelling or a cold, pale or blue foot. Book reassessment if ordinary activities remain limited or symptoms continue to worsen.

What is the likely source of my knee pain? When should I judge whether the injection helped? Which exercises and activities are suitable during recovery? What are the next options if my walking and sleep do not improve?