|
|
|
|||
| Homepage Site Map General Information Clinical Care Fibromyalgia Research Foundation
The Metabolic Treatment Read About Our New Book
Titled |
Trigger
Point Referral
December 8, 2001 Dr. Lowe: It is unlikely that you irritating the dorsal scapular nerve. Instead, you were affecting neural circuits in the spinal cord that gave rise to the perception of discomfort at the medical border of your scapula. From your description, you were applying the ultrasound to a trigger point in either the anterior or medical scalene muscle. After turning the ultrasound intensity up higher, you stimulated the perception of referral to the medial border of your right scapula. The referral pattern is one typical of trigger points in the scalene muscles (see the drawing below).
Ultrasound exerts a mechanical force on tissues. When that force is strong enough, it will activate referral from a trigger point. The effect is similar to you applying pressure to the trigger point with a finger or thumb. The irritable nerve endings embedded in the fascial layers around the tense muscle fibers of the trigger point area are mainly type C receptors. These are mechanoreceptors that respond to mechanical force. When these receptors are irritable enough, fairly low amounts of pressure (from a finger or ultrasound) activate them. The type C nerve fibers then begin transmitting nerve signals that produce the perception of referral to another body location. If you palpate your right anterior and medial scalene muscles with the fingers of your left hand, you can find the trigger point you were affecting with the ultrasound. With your fingers, search for an exquisitely tender spot. When you find it, pressure into it firmly for 10 or 20 seconds. Mostly likely, you'll stimulate a referral pattern similar to that you felt under the influence of the ultrasound. Of course, you may find more than one trigger point. Sustaining pressure into each will show which one was referring to your scapula. We can use ultrasound as you did to confirm the location of a trigger point. However, palpation is usually just as effective in finding trigger points. Nonetheless, the experience you had with referred sensation by ultrasound is instructive for you as a practitioner. I personally believe that experimenting with yourself is one of the best teaching tools for learning myofascial trigger point therapy. Through experimenting on yourself, you can learn how to find and effectively treat trigger points. Once you find a trigger point, you can treat it properly. Ultrasound is one effective method, although it’s certainly not the only one. To treat a trigger point properly with ultrasound, keep the intensity low enough not to stimulate referral. If you use an intensity high enough to stimulate referral, you’re likely to leave the trigger point irritated. This is counterproductive in that your aim is to lower or stop the irritability of the trigger point. You’ll find that when you use an ultrasound intensity high enough to keep the skin warm, but not so high as to cause referral, the treatment will be soothing. Unless some underlying factor keeps the trigger point irritable, five minutes or so of continuous ultrasound usually stops the referral of an active trigger point or decreases the tenderness of a latent trigger point. When you also use specific muscle stretches and moist heat, and you carefully avoid overloading the muscle, you can desensitize trigger points so that they cease to be a problem. |
|||
