Trigger points are sensitive areas in the body that are made up of taut bands of muscle that fail to relax because of stress, overuse, or other unknown causes. These areas, when palpated, feel tough and ropelike under the skin, are very painful when pressed, and may twitch involuntarily.
Trigger points are classified according to their current effect on the body, making them either active or latent. Active trigger points cause pain even at rest, and the pain may not be localized to the trigger point alone, but may radiate to other areas that also become tender to touch. Latent trigger points, on the other hand, are painful only when applied pressure to, but still cause restrictions in movement and functional activities.
Relief of trigger points may vary with different modalities and techniques. Physical therapy, spray and stretch, and ultrasound are used to treat trigger points, but not all respond fully to these treatments. Chronic conditions may cause trigger points that are not relieved easily, so trigger point injections become the treatment option of choice. A local anesthetic is injected directly into the affected area to block pain at the origin.
A trigger point injection treatment session can treat multiple points in a short amount of time, and the pain experienced is comparable to having blood drawn or having an IV inserted. At times, patients may feel sore and have a couple of bruises, but this resolves quickly.
The chronicity of the trigger point will determine the response to injection treatment. Numbness is to be expected in the area for a few hours post-injection, but can give patients pain relief for a month.