A cortisone injection delivers a potent anti-inflammatory medication (a corticosteroid) directly into a specific area like a joint, tendon sheath, or bursa. This targeted approach reduces localized swelling, irritation, and pain caused by various musculoskeletal conditions. The injection’s purpose is not to cure the underlying problem, but to create a window of opportunity where reduced pain allows for effective physical rehabilitation. It calms aggravated tissues, making movement and strengthening exercises possible, which are the true drivers of long-term recovery.
Immediate Post-Injection Care
Following a cortisone injection, the immediate priority is protecting the treated area for the first one to three days. Healthcare providers typically recommend relative rest, avoiding strenuous activities, heavy lifting, or high-impact exercise for at least 24 to 48 hours. This initial rest allows the medication to settle and begin its work without being compromised by excessive mechanical stress.
The corticosteroid does not provide instant pain relief; full anti-inflammatory effects can take several days to become noticeable. Some patients experience a temporary increase in pain, known as a “cortisone flare,” as the steroid crystals irritate the tissue before dissolving, usually lasting up to 48 hours. Applying ice to the injection site can help manage soreness or swelling, but heat should be avoided.
Finding the Optimal Window for Starting Physical Therapy
The timing for initiating physical therapy is highly individualized, but it generally begins once the initial discomfort has subsided and the anti-inflammatory effect of the cortisone has started. This optimal window for starting formal rehabilitation typically falls between three to seven days post-injection. Starting too soon risks exacerbating inflammation, while starting too late wastes the period of maximal pain reduction.
The precise start date must be determined in consultation with the prescribing physician and the physical therapist, taking into account the injection site. For example, a non-weight-bearing joint like the shoulder may allow for earlier gentle mobilization compared to a weight-bearing joint like the knee or hip. The patient’s individual response, including the severity of the initial pain flare and the speed of subsequent relief, is a significant factor in adjusting the timeline. The primary goal is to leverage the pain-free state created by the injection to safely begin necessary movements.
How Physical Therapy Maximizes Long-Term Results
Physical therapy addresses the underlying mechanical issues that led to the inflammation, which the injection alone cannot resolve. Cortisone provides symptomatic relief, but it does not correct poor movement patterns, muscle imbalances, or joint stiffness. The reduced pain allows the patient to perform exercises that were previously too painful, transforming a temporary fix into a lasting correction.
The rehabilitation program typically progresses through two phases, beginning with gentle mobilization and range-of-motion work. This initial phase focuses on restoring normal joint mechanics and flexibility, taking advantage of the reduced inflammatory barrier. The therapy then progresses to strengthening and stability exercises designed to build muscle support around the joint and prevent future injury recurrence. This progression ensures that the benefits gained are maintained long after the steroid’s effects have worn off.
Recognizing Complications and When to Delay Treatment
While cortisone injections are generally safe, patients must be vigilant for signs of complication that require delaying or immediately stopping physical therapy. The most serious concern is a joint infection, a rare but severe side effect. Symptoms of an infection include increased redness, warmth, significant swelling at the injection site, fever, or chills.
If a sudden, severe increase in pain occurs that is disproportionate to the physical therapy activity, the session should be stopped, and the physician contacted. Other warning signs include new or worsening signs of nerve damage, such as numbness, tingling, or weakness in the limb. Maintaining clear communication with both the physical therapist and the prescribing doctor is essential to ensure the rehabilitation program is safe and effective.