Cortisone shots are a common treatment for knee pain, aimed at reducing inflammation and alleviating discomfort within the joint. These injections deliver a powerful anti-inflammatory medication directly into the knee, providing targeted relief. They are often used to manage symptoms arising from conditions like osteoarthritis, tendinitis, or bursitis.
How Long Relief Typically Lasts
The duration of pain relief from a cortisone shot in the knee varies among individuals, typically ranging from a few weeks to several months. Many patients experience relief for about six weeks to six months, with some studies indicating a significant benefit for approximately three months. While some may find relief lasting over a year, this often involves multiple injections. The effects are not always immediate; some individuals experience initial increased pain for a day or two before relief begins, and full effects can take up to a week.
Factors Affecting Duration
Several factors influence how long the effects of a cortisone shot last in the knee. The specific knee condition being treated, such as the severity of osteoarthritis or the type of injury, plays a role; more severe cases may experience shorter relief. An individual’s overall health, including activity level and unique response to the medication, also affects the outcome. The formulation of the cortisone shot can also be a factor, as some are designed for slower release. Repeated injections over time might lead to shorter periods of pain relief as the underlying condition progresses.
What Cortisone Does in the Knee
Cortisone, a type of corticosteroid, is a synthetic version of cortisol, a hormone naturally produced by the body’s adrenal glands. When injected into the knee joint, it acts as a powerful anti-inflammatory agent. Cortisone works by suppressing the immune response and inhibiting the production of inflammatory molecules. This action directly reduces swelling, pain, and inflammation within the joint space, which improves mobility. The goal is to calm inflammatory processes that contribute to discomfort, though it does not address the underlying cause of the condition.
Important Considerations
As the effects of a cortisone shot wear off, pain and inflammation commonly return, as these injections are not a permanent solution and their use is limited due to potential risks. Healthcare providers recommend limiting cortisone shots to no more than three or four times per year in the same joint, with at least three months between injections. Frequent injections can lead to complications such as cartilage or bone damage, or weakening of tendons and ligaments. Temporary side effects can include increased pain or a “cortisone flare” at the injection site, temporary elevation in blood sugar, and skin changes. Discuss these with a healthcare professional for guidance on ongoing management or alternative treatments.