A cortisone shot is an anti-inflammatory injection administered directly into a joint space, such as the knee, to deliver potent corticosteroid medication. This targeted treatment aims to reduce localized pain and swelling. A common concern for many people considering this procedure is the pain associated with the injection itself. Understanding the sequence of sensations and the medical techniques used to manage discomfort can help alleviate anxiety.
The Injection Sensation: What to Expect During the Procedure
The immediate sensation of receiving a cortisone shot is typically brief and described more as pressure than sharp pain. Before the injection, the clinician cleanses the skin and may apply a topical cooling spray for momentary numbing. The initial discomfort is usually the quick prick of the needle as it penetrates the skin.
The medication injected is a mixture containing the corticosteroid and a local anesthetic, such as lidocaine, which acts immediately. As the needle advances toward the joint space, a person might feel a deeper, dull sensation, but the anesthetic quickly numbs this path.
Once the needle tip reaches the synovial space, the most noticeable sensation is often a feeling of fullness or internal pressure. This occurs as the volume of the mixture is pushed into the joint capsule, temporarily expanding the space. This pressure can be intense for a few seconds.
The entire injection process is very quick, often lasting less than a minute. While some discomfort is unavoidable, the local anesthetic ensures that sharp pain is minimal and fleeting. Patients should communicate any significant discomfort to the physician.
Minimizing Discomfort: Techniques Used by Physicians
Physicians employ several strategies to ensure the cortisone injection procedure is comfortable. The most effective method is mixing a fast-acting local anesthetic, like lidocaine, directly with the corticosteroid solution. This mixture ensures that pain relief begins instantly as the medication is delivered into the knee joint.
Another technique involves using a topical refrigerant spray, which rapidly cools the skin at the injection site. This temporary freezing effect numbs superficial nerve endings, dulling the sensation of the initial needle puncture. Physicians also use the smallest gauge needle appropriate for the procedure to minimize tissue trauma.
To increase accuracy and avoid repeated attempts, many practitioners utilize real-time image guidance, such as ultrasound. This allows the physician to visualize the needle tip’s path, ensuring precise placement within the joint capsule. Precision minimizes the need for probing or repositioning the needle, reducing the overall duration and discomfort.
After the Shot: Understanding the Cortisone Flare
Distinct from the immediate procedural discomfort is a delayed reaction known as a “cortisone flare,” which can occur hours after the injection. This flare is characterized by a temporary increase in pain, warmth, and swelling in the knee joint, beginning as the initial numbing effect of the local anesthetic wears off. This renewed pain is due to chemical irritation, not poor technique or infection.
The flare is caused by the corticosteroid medication itself, which is often formulated as crystalline particles for slow release. These microscopic crystals temporarily irritate the sensitive joint lining before they dissolve and begin their anti-inflammatory action. This reaction occurs in a minority of patients, affecting about one in five people who receive the shot.
The discomfort of a cortisone flare is short-lived, typically peaking within the first 24 hours and resolving completely within 48 to 72 hours. Management focuses on reducing localized inflammation. Applying an ice pack to the knee for 15 to 20 minutes at a time can help calm the irritated joint.
The physician will recommend resting the joint and avoiding strenuous activity for a couple of days. Over-the-counter pain relievers, such as acetaminophen or ibuprofen, may also be suggested to manage the discomfort until the flare subsides. Once the temporary irritation passes, the therapeutic benefits of the corticosteroid begin, leading to the desired reduction in chronic knee pain.