Cortisone is a hormone secreted by the adrenal gland, which is a small gland next to the kidney. This gland secretes many different kinds of hormones needed for regulation of body processes. Some regulate sodium and potassium, some have an effect on blood sugar , protein and fat metabolism, and some have the same effect as the sex hormones.
Cortisone is needed by metabolic systems for utilization of carbohydrates, proteins and fats, and for resistance to physical and mental stress and infections. The adrenal gland releases cortisone in response to stress caused by trauma, infection, intense heat or cold, surgery, and almost any debilitating disease.
Cortisone is primarily used therapeutically for its anti- inflammatory properties. It is the body’s most powerful natural resistance to inflammation.
Swelling causes inability to move joints, and is a natural method of immobilization. Swelling causes us to avoid using or touching the painful area, so as to rest the part involved.
The four main signs of inflammation are REDNESS, SWELLING, HEAT, and PAIN. Inflammation is a normal process which is set into motion by a complex series of events which try to heal the damaged body tissues. However, the inflammation itself may be potentially harmful.
Cortisone, made by the body, is indicated for the treatment of most inflammatory conditions and some non-inflammatory conditions. For localized injections, manmade cortisone-like preparations are used. (The cortisone injections referred to here are not to be confused with the anabolic steroids used by some athletes to enhance their physical performance.) The manmade preparations are more potent anti-inflammatories with less side effects than cortisone.
The inflammatory conditions which usually respond to a local cortisone injection are:
The non-inflammatory conditions which respond to local cortisone injections are:
Symptom improvement can occur within the first 24 hours; improvement in pain and stiffness is sometimes dramatic. Maximal relief from pain and swelling usually is accomplished within 3 days, and may continue for up to two weeks or longer.
Local injections of a small amount of cortisone have very few reactions compared to long-term cortisone therapy. Local injections use a small amount of cortisone injected into a small, limited area, and is usually fully absorbed in two weeks or less. The cortisone used is not long-acting, allowing for quicker absorption.
Your doctor can answer any questions you may have regarding cortisone injection therapy.
Use of cortisone injections in the treatment of muscle and joint inflammatory reactions is becoming increasingly popular. First popularized by Janet Travell, MD, muscle injections are a remarkably effective adjunct to pharmacologic and physical therapies and are safe and easy to perform. Joint injections, while technically more difficult to perform, also can be of great benefit in the patient’s recovery. The purpose of this article is to introduce the basic principles of muscle and joint injections. Other references can provide specific details on how to inject at a given anatomic location, such as for bursitis, tenosynovitis, or intra-articular inflammation.
Inflammation is one of the body’s first reactions to injury. Release of damaged cells and tissue debris occurs upon injury. These expelled particles act as antigens to stimulate a nonspecific immune response and to cause proliferation of leukocytes. Increase of local blood flow develops to transport the polymorphonuclear leukocytes, macrophages, and plasma proteins to the injured area. A redistribution of arteriolar flow produces stasis and hypoxia at the injury site. The resultant infiltration of tissues by the leukocytes, plasma proteins, and fluid causes the characteristic red swollen painful inflammation.
Inflammatory muscle and joint injuries are associated with many causes, including muscle strains, trauma, polyarthritis, connective tissue disease, degenerative joint disease (DJD), tendonitis, bursitis, arthritis, neoplasm, inherited congenital disorders, and miscellaneous systemic diseases.
Initially, the inflammatory reaction serves several important purposes. The influx of leukocytes facilitates the process of phagocytosis and removal of the damaged cells and other particulate matter. Pain and tenderness serve to remind the patient to protect and guard the injured area; however, the inflammatory reaction eventually becomes counterproductive. The extravascular pressure exerted by the edema may retard blood flow into the area and delay healing. Sometimes, the debris coagulates and forms hard masses, scarring, and/or trigger points in the muscle or joint, preventing the return to normal function.
The mechanism of action of corticosteroids includes reducing the inflammatory reaction by limiting the capillary dilatation and permeability of the vascular structures. These compounds restrict the accumulation of polymorphonuclear leukocytes and macrophages and reduce the release of vasoactive kinins. They also inhibit the release of destructive enzymes, which not only attack the injury debris but also destroy normal tissue indiscriminately. Additionally, new research suggests that corticosteroids may inhibit the release of arachidonic acid from phospholipids, thereby reducing the formation of prostaglandins, which contribute to the inflammatory process. Finally, the clinician should appreciate the importance of introducing a needle into the injured area. The needle itself may provide drainage and release of pressure, and it also may disrupt the scar tissue mechanically in the muscle.
As with the treatment of any disorder, a careful history and physical examination are of paramount importance. Sharp severe intense pain suggests a more acute traumatic and marked inflammatory reaction. Dull low-grade chronic pain indicates a mild inflammatory reaction, chronic overuse injury, or arthritis. Radiation of pain or additional neurologic symptoms (eg, tingling, burning, numbness) imply additional neurologic involvement. Medication history is important, as discontinuation of anti-inflammatory medications often precipitates a reaction. Dietary changes may precipitate reactions like, for example, an attack of gout.
The physical examination is performed to assess the location and severity of the reaction. Determination of whether the inflammation is in the muscle, tendon, or joint is of paramount importance. Trigger points in muscles can be identified easily if the clinician uses the appropriate palpation skills. Many clinicians frequently ask their patients to identify the site of their greatest discomfort. Patients often know exactly where the source of their pain is, since they have spent hours localizing it.
Radiographic studies may or may not be beneficial, as it takes a significant amount of effusion to appear on a routine radiograph. Usually, clinical symptoms are present and treatable long before a radiographic abnormality may be identified. On the other hand, radiographs are important in evaluating for fracture or determining the acuity.
If joint and cartilage damage exists, the clinician knows that a long-standing process is involved. Electromyograms (EMG) are extremely beneficial in determining whether there is a significant neurologic component to the patient’s symptoms. This determination is important in targeting sites for injection. Blood work can include blood counts and chemistry series. An elevated leukocyte or white blood cell (WBC) count may indicate infection. An elevated erythrocyte sedimentation rate (ESR) suggests a significant myopathic or arthritic process has developed. Elevated rheumatoid factor (RF) implies chronic arthritic conditions such as rheumatoid arthritis. Elevated uric acid levels sometimes may be observed in patients with gout.
Treatment of the patient with an inflammatory condition involves a multidisciplinary approach. Anti-inflammatory medications (eg, aspirins, nonsteroidal anti-inflammatory drugs [NSAIDs], oral prednisone) are indicated in patients with both acute and chronic inflammation. Remember that it is important to use a full therapeutic dose initially. Many patients tend to discontinue their medication after they begin to feel better and leave a low-lying inflammatory reaction. This author recommends prescribing the NSAID first as a 10-14 day prescription with instructions to use it up entirely. Then, follow this up with an as-needed (prn) prescription.
Nonnarcotic pain medications such as Elavil may be beneficial in reducing the pain associated with inflammatory reactions. Although this is an area of some controversy, in the opinion of this author, the use of narcotic medications is contraindicated. Narcotic medications may set up a dependency reaction, which can escalate very quickly.
In acute situations, rest, ice, heat, splinting, and bracing are important principles of care. With time, physical therapy, massage therapy, and general rehabilitation management become increasingly effective. In the opinion of this author, a treating physician also should avoid the temptation to respond to the patient who arrives for treatment determined to get an injection for a quick fix and is unwilling to try conservative therapy options first. While injection therapy is relatively safe, there are inherent dangers in any procedure where the skin is pierced, including infection, bleeding, and perforation of vital structures. Every baseball season, a story appears about a player who had an injection performed and wound up with a collapsed lung.
Indications for injection therapy may include any of the following inflammatory reactions:
Precautions for injection therapy include the following:
The packing insert for corticosteroids lists additional significant precautions and contraindications. The physician should be familiar with all these restrictions before considering injection therapy.
Potential local side effects of corticosteroid injections include infection, subcutaneous atrophy, skin depigmentation, and tendon rupture. These complications often are the result of poor technique, too large a dose, too frequent a dose, or failure to mix and dissolve the medications properly.
Regarding injections for myofascial pain, some clinicians prefer to perform trigger point injections that contain corticosteroid while others prefer to perform trigger point injections with only local anesthetics or no medication at all (“dry needling”).
The procedure for injection therapy is uncomplicated and well established. The object is to inject the corticosteroid preparation with as little pain and as few complications as possible. The technique is similar for muscle, periarticular, or articular injections. Selection of the site and careful attention to surface and deep anatomy are of paramount importance. Do not attempt any injections in the vicinity of known nerve or arterial landmarks. For example, a lateral epicondyle injection is relatively easy. An injection into at the medial epicondyle (near the ulnar nerve) carries greater risk, and extra care must be taken to identify the nerve, outline its course, and avoid it.
Sterile technique is recommended when performing injections. This added care is needed to minimize the risk of iatrogenic infection, especially important for intra-articular injections.
Various opinions abound regarding whether to use give a separate injection with just a local anesthetic (eg, lidocaine) prior to the corticosteroid injection. Some physicians prefer to give one injection (the corticosteroid preparation, perhaps mixed with a local anesthetic). Their rationale is that one needle is less painful than two; however, the cortisone injection involves a thicker material and, therefore, they use a larger gauge needle. Thus, this author prefers a 2-needle technique, feeling that this method is better tolerated by patients. The 2-needle technique starts with the physician anesthetizing the area with a small 25-gauge needle, waiting 3-5 minutes for the anesthesia to have full effect, and then using a larger bore needle (18-21 gauge) for the corticosteroid injection.
Remember that the povidone-iodine solution should dry on the skin to have its full antibacterial effect. Just swabbing on the disinfectant and injecting increases the risk of infection. Another important tip is to consider changing the needle used to aspirate the medication into the syringe with the one used to do the injection, especially when using multidose vials. Finally, gentle distraction of the joint being injected may improve accessibility.
The material used for the injection is left to the discretion of the physician. Numerous philosophies and theories exist for the different materials that are available. Many physicians prefer a simple long-acting methylprednisolone preparation. This author prefers a cocktail of equal parts of (1) lidocaine, (2) triamcinolone, which is intermediate acting (40 mg/mL), and (3) dexamethasone, which is long acting (4 mg/mL).
For muscle trigger point injections, the needle is inserted directly into the trigger point. Always withdraw the plunger to confirm that a blood vessel has not been penetrated before injecting the cortisone. The needle may remain in place but can be moved up and down and turned without withdrawing it from the skin. The needle should be angled into 3-4 areas of the trigger point.
Remember that some of the benefit of the injection is the mechanical disruption of the scar tissue. For periarticular injections, do not inject directly into the tendon lest the patient develop mechanical disruption or weakening of the tendon. Injection of the cortisone is accomplished in small droplets around the area of inflammation. Multiple injections may be required to infiltrate several centimeters of the tendon and muscle. Joint injections are accomplished by inserting the needle directly into the joint. Identification of joint injection sites is beyond the scope of this article, but information can be found easily in several guides to injection. My personal favorite reference for muscle trigger points is Myofascial Pain and Dysfunction by Janet Travell.
Following the injection procedure, it is often helpful to ice the area. The injection itself is traumatic and results in swelling and edema, the very problems requiring treatment. Immediate icing of the area reduces this inflammatory response. Explain to the patient what to expect. For the first 2 hours, the patient may feel great because the area is numb from the local anesthetic. Unfortunately, this lack of discomfort only lasts 2 hours and is replaced by increased pain, often worse than before the injection. Remind the patient that a needle has been stuck into a sore spot. This increased tenderness often lasts 2 days and should be treated with ice at home. By warning the patient up front, the clinician can avoid many emergency calls. Obviously, the patient also should be cautioned that any unexpected symptoms (eg, excessive bleeding, allergic reactions, chest tightness, wheezing) should be evaluated immediately in an emergency department.
Frequently, multiple injections are required for comprehensive treatment of the patient. Typically, patients have multiple trigger points, and 3 sets of injections are required; however, it has been this author’s observation that administration of up to 10 rounds of trigger point injections may be necessary. Each week, the patient may return with a new “worst spot.” This phenomenon tends to be more common in patients with chronic muscle disorders such as fibromyalgia or chronic pain syndromes. Tendon and joint injections generally are limited to no more than 3 in one joint per calendar year because of the potential for mechanical disruption of the joint space and structures.
In conclusion, the use of corticosteroid injections can be a useful addition to the treatments employed in treating musculoskeletal and joint injuries and pain. An injection regimen is most effective when combined with pharmacologic and rehabilitation techniques, such as administration of NSAIDs, stretching, and modalities (eg, ice, heat). Injection of corticosteroids is a relatively safe procedure that can be managed by specialists and general practitioners alike. Treatment with corticosteroids has been a vital part of this author’s practice of medicine and can be used to benefit many other physicians and patients as well.