Corticosteroid injections are safe and effective procedures for musculoskeletal and joint injuries, inflammations and pain.
Inflammation is the initial reaction of the body to injury. Causes of inflammatory muscle and joint pain include: arthritis, bursitis, connective tissue injury, degenerative joint disease, muscle strains, tendonitis, trauma, and certain systemic diseases.
The initial inflammatory process facilitates the removal of damaged cells and other particulate matter. Pain and tenderness remind the person to protect the injured area. But the inflammatory reaction can eventually become counterproductive. The swelling and edema can interfere with blood flow and delay healing. Debris may coagulate and form hard masses, scarring, and/or trigger points in the muscle or joint, preventing return of normal function.
Corticosteroids reduce the inflammatory reaction by limiting the capillary dilatation and permeability, inhibit the release of destructive enzymes that attack the injury debris and destroy normal tissue indiscriminately and may inhibit the release of arachidonic acid, therby reducing the formation of prostaglandins, which contribute to the inflammatory process.
The insertion of a needle itself may provide drainage and a release of pressure, may also mechanically disrupt scar tissue in the muscle.
Sharp, intense pain suggests an acute, traumatic reaction with marked inflammation. Dull, chronic pain indicates a mild inflammatory reaction, a chronic overuse injury, or arthritis. Radiation of pain orl neurologic symptoms ( tingling, burning, numbness) implyl neurologic involvement.
Determination of whether the inflammation is in the muscle, tendon, or joint is of paramount importance. Frequently, patients can best identify exactly where the source of their pain is, having spent hours experiencing it.
X-rays may or may not be beneficial, because it takes a significant amount of edema for the injury to appear on a routine radiograph. Usually, clinical symptoms are present and treatable long before a radiographic abnormality may be identified; however, x-rays are important in evaluating for fractures.
Anti-inflammatory medications (aspirin, nonsteroidal anti-inflammatory drugs [NSAIDs], oral prednisone) are indicated for acute and chronic inflammation.
Nonnarcotic pain medications, such as amitriptyline, may be beneficial in reducing the pain associated with inflammatory reactions.
The use of narcotic medications is dependent on the severity of pain, and these drugs are used only for a limited duration.
In acute situations RICE: rest, ice, heat, splinting, and bracing are important elements of treatment. In time, physical therapy, massage therapy, and general rehabilitation become increasingly effective.
Even though injection therapy is safe, there are the inherent dangers in any procedure where the skin is pierced, including infection, bleeding, joint ruptures, and perforation of vital structures.
Indications for injection therapy include the following inflammatory conditions: bursitis, carpel tunnel syndrome, fasciitis, ganglion cyst, neuroma, osteoarthritis, synovitis, tendonitis and trigger points.
Precautions for injection therapy include the following: infection, tumor, neurogenic disease, active infections, immune-suppression, hypothyroidism, bleeding dyscrasias, uncontrolled diabetes, joint prosthesis, surrounding joint osteoporosis and patellar or Achilles tendinopathies.
The procedure for injection therapy is simple 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.
Sterile technique is utilized when performing injections. This added care is needed to minimize the risk of iatrogenic infection and is especially important for intra-articular injections.
Some of the benefit of the injection is the mechanical disruption of scar tissue. 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.
The patient needs to appreciate that a needle has been stuck into a sore spot. This increased tenderness often lasts 2 days and should be treated at home with ice. By warning the patient up front of the level of pain to expect, the clinician can avoid many emergency calls.
Frequently, multiple injections are required for comprehensive treatment of the patient. Typically, patients have multiple trigger points and 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 a chronic muscle disorder, such as fibromyalgia or a chronic pain syndrome. Tendon and joint injections generally are limited to no more than 3 in 1 joint per calendar.