Trigger points are spots in the muscle that radiate pain. This pain can cause headaches or interfere with rehab and function. Trigger point injections are localized shots injected directly to the painful area to alleviate pain, so that comfort and function can be regained.
Trigger points are tender muscles that send a pattern of pain to other areas of the body when palpated or touched. These tender points are usually felt as knots or bands that do not relax. Trigger points can be localized to one area of the body such as the muscles that support the neck. They can also occur in multiple areas throughout the entire body.
Trigger points can become problematic for a number of reasons. Patients may develop trigger points because of injury to muscle tissue. Examples of muscular injury include whiplash, overuse of a muscle group or a post-viral syndrome. Trigger points may also occur because of an underlying structural problem. Spinal abnormalities such as herniated and degenerative discs, scoliosis, postural problems and osteoarthritis are examples of conditions commonly associated with trigger points.
A trigger point injection is an injection into a tender muscle. Examples of substances injected include local anesthetics, corticosteroids, saline solution and dextrose.
Local anesthetics act to increase blood flow by dilating blood vessels in the muscle. This helps to rid the muscle of inflammatory substances that accumulate when muscles go into spasm. Corticosteroids are anti-inflammatories. These medications help to block inflammation. Inflammatory substances in the muscle produce pain by sensitizing nerve endings and receptors. In addition, the physical force of the fluid helps to break muscle spasm and adhesions.
Trigger point injections are very safe. Patients may feel some injection site tenderness following the injection as the local anesthetic wears off. It may take a few days for the anti-inflammatory action of the steroid to take effect. Patients will sometimes feel a little dizzy for up to an hour if multiple trigger points are injected with a large dose of local anesthetic.
A definitive answer is not possible because it depends on the nature of the patient’s condition. The local anesthetic will numb the area for one to three hours. The corticosteroids remain in the tissue in active form for about one month. The major benefit of trigger point injections is to allow the patient to move effectively so he / she can participate in a rehabilitative program. Trigger point injections loosen muscle groups thereby improving patient progress in physical therapy and joint mobilization.
If trigger point injections are not effective in reducing your pain, other modalities are available (such as medical management, nerve blocks, electrical stimulation techniques, intradiscal techniques, and radiofrequency) to control pain depending on your condition.