A cortisone shot, also known as a corticosteroid injection, is a common medical procedure used to treat musculoskeletal conditions involving inflammation, such as arthritis, bursitis, and tendonitis. The medication is a powerful anti-inflammatory agent that mimics hormones naturally produced by the adrenal glands. By delivering a concentrated dose directly into a specific area—like a joint, tendon sheath, or bursa—the injection targets localized swelling and irritation. This targeted approach provides significant pain relief and reduces inflammation, often allowing a patient to participate more effectively in physical rehabilitation.
Understanding Expected Onset and Degree of Relief
The experience of a cortisone shot “working” is not instantaneous, and understanding the expected timeline is important to avoid prematurely concluding the treatment has failed. The injection contains a fast-acting local anesthetic and the corticosteroid medication. The anesthetic provides immediate but temporary pain relief, often wearing off within a few hours, which can lead to a brief return of discomfort before the steroid takes effect.
The anti-inflammatory action of the corticosteroid usually begins within 24 to 72 hours following the injection. The full therapeutic effect can take up to a week, or sometimes even two weeks, depending on the specific condition and severity of the inflammation. Pain relief from a successful injection can last anywhere from several weeks to a few months, with many patients experiencing relief for six to twelve weeks.
A successful outcome often means partial relief, not total pain eradication. The goal is a significant reduction in pain and swelling to improve function and quality of life. If the underlying condition is severe, the relief may be less dramatic or shorter-lived. Tracking pain levels consistently helps distinguish a slow-acting response from a true treatment failure.
Primary Causes for Injection Ineffectiveness
When a cortisone shot fails to provide adequate relief after the expected onset period, it signals that the initial treatment plan did not fully address the source of the pain.
Inaccurate Diagnosis
One of the most common reasons for failure is an inaccurate diagnosis of the underlying problem. Cortisone reduces inflammation, but if the primary source of pain is not inflammation—such as a structural joint problem, nerve compression, or a mechanical issue—the injection will not be effective. For instance, if the pain is due to nerve irritation or referred pain from the spine, injecting the shoulder joint will not provide lasting relief.
Advanced Pathology
Another significant factor is advanced pathology, where the underlying condition is too severe for a solely anti-inflammatory treatment to be effective. Patients with late-stage conditions, like severe osteoarthritis where cartilage is worn down, experience pain primarily from bone-on-bone contact and degeneration. In such cases, the anti-inflammatory properties of the corticosteroid cannot reverse the structural damage, making the pain relief marginal or non-existent. A complete tendon tear or a large bone spur requires mechanical intervention, not chemical suppression of inflammation.
Technical Placement
Technical placement of the medication also plays a substantial role in the injection’s success. The cortisone must be delivered directly into the precise location of the inflammation to exert its effect. If the medication is deposited slightly off-target, especially when the injection is performed without imaging guidance like ultrasound or fluoroscopy, the anti-inflammatory agent may not reach the source of the pain. Even with guidance, minor variations in anatomy or technique can reduce the efficacy.
Lack of Biological Response
Finally, some individuals experience a lack of biological response to the steroid, which is a patient-specific factor. Though rare, a person may metabolize the medication too quickly, or the specific inflammatory process involved may be inherently resistant to corticosteroids. A treatment failure often serves as a diagnostic signal, indicating that the patient’s condition is more complex or severe than initially assessed.
Next Steps Following a Failed Cortisone Treatment
When a cortisone injection fails to deliver the expected relief, the medical pathway shifts from symptom management to a more rigorous diagnostic and treatment strategy. The physician will often first recommend further diagnostic imaging to gain a clearer picture of the tissue damage. Since initial X-rays may not reveal soft tissue problems, a failed cortisone shot frequently prompts an order for advanced imaging, such as a Magnetic Resonance Imaging (MRI) scan or a Computed Tomography (CT) scan.
These scans can identify structural issues that were previously missed, such as significant tendon tears, severe nerve impingement, or advanced degeneration. Once a clearer diagnosis is established, the focus moves to alternative treatment modalities. Physical therapy is frequently the next step, as it addresses the underlying biomechanical or movement problems that may be causing the irritation in the first place.
Other non-surgical options may include different types of injections, such as hyaluronic acid to lubricate joints affected by osteoarthritis, or regenerative treatments like Platelet-Rich Plasma (PRP) injections. Only after conservative treatments have repeatedly failed to provide lasting relief will a surgical consultation become the next logical step. This evaluation determines if the identified structural damage—like a full tear or severe joint destruction—is best corrected through an operative procedure.