Knee injections — most commonly corticosteroid (steroid) injections or hyaluronic acid injections — can reduce pain and improve function in selected patients with knee osteoarthritis. They are typically used as part of a broader non-surgical management plan, not as a standalone treatment. The duration of benefit varies significantly between patients and between injection types, ranging from a few weeks to several months.
Corticosteroid injections work by reducing inflammation and are most useful when the knee is acutely inflamed and swollen. Their benefit is often temporary, and repeated injections over a short period are generally avoided. Hyaluronic acid injections aim to supplement the joint fluid and may provide longer-term symptom relief in some patients, though the evidence is mixed. Injections do not halt or reverse the underlying arthritis. In patients with very advanced joint damage, they are unlikely to provide meaningful or sustained relief, and surgery should be discussed.
