How Long Does a Cortisone Injection Take to Work for Knee Osteoarthritis?

The local anaesthetic used with some injections may ease pain shortly after the procedure. That early effect can fade before the corticosteroid reduces inflammation inside the knee. Osteoarthritis can make walking, stairs, standing, and getting up from a chair uncomfortable, and symptoms may vary with activity. The injection may make these tasks easier for a period, but it does not restore worn joint surfaces or remove every source of pain. Your response is useful information for deciding whether the knee joint is contributing to symptoms.

Keep to the activity limits provided by the treating clinician, especially during the early post-injection period. When permitted, resume walking and exercises in small increments rather than making a sudden return to long walks, deep bending, or heavy lifting. Physiotherapy can address strength, balance, and movement habits that affect knee loading. Track pain during daily tasks, swelling, sleep, and how long relief lasts. This helps distinguish a short-lived change from a useful improvement in function.

Call the treating service if the knee becomes increasingly red, hot, swollen, or painful, or if you develop fever or feel unwell. Seek urgent care if you cannot bear weight, develop marked new weakness, or have sudden severe swelling. If there is no improvement by the follow-up timeframe provided, arrange a reassessment rather than increasing activity to test the knee.

Ask when normal walking, stairs, strengthening, and sport can resume. Ask how to respond to a flare, how long to monitor the result, and which non-injection options may support knee function if relief is limited.