Trigger Point Injections
A trigger point is a localized area of muscle that causes pain in a remote area when the muscle is firmly pressed on. The term ‘trigger point’ was coined in 1942 by Dr. Janet Travell, who served as John F. Kennedy’s physician. She proposed a new term: myofascial, combination of muscle and fascia. She proposed that a trigger point is a focal hyperirritability in muscle that can modulate central nervous system functions resulting in radiating muscle type pain.
Trigger points are often tender, firm knots in the muscles that when pushed, can feel as small as a pea or as large as a walnut – embedded within the muscle tissue. The pain one feels from pressing on a trigger point usually radiates in a region that is away from the trigger point.
When trigger points are firmly pressed, the entire muscle can twitch or spring into spasm. Trigger points are often located in the neck, back or shoulder muscles, and can cause pain in all the muscles close by. Trigger points are diagnosed by examining signs, symptoms, pain patterns and manual palpation.
Trigger points can appear in many myofascial structures, including muscles, tendons, ligaments, skin, joint capsule, periosteal, and scar tissue. They can be caused by acute or chronic muscle overload, activation by other trigger points, disease, psychological distress, direct trauma to the region, infections or simply by pain nearby.
Treatment of trigger points include ultrasound, electrostimulation, ischemic compression, injection, and alternative therapies like massage, acupuncture. Injections provide more immediate relief, and can be effective when other methods fail. Various injections can be used, including saline, local anesthetics such as lidocaine, steroids, and Botox. (Clinical Journal of Pain. Retrieved on 2008-01-25).