This presentation and this module is on myofascial pain. This module has five parts. We're going to talk about clinical characteristics, we're going to to talk about the various causes of myofascial pain, we're going to cover perpetuating factors to myofascial pain, we're going to go into the trigger point examination techniques, and then we're going to talk about a few management strategies. So those are the different parts of this module. Today we're going to cover clinical characteristics. So myofascial pain is a clinical syndrome of regional soft tissue pain that arises from skeletal muscle. It's a regional referred pain syndrome. It's associated with focally tender trigger points in skeletal muscle. It is a very prevalent cause of pain in all parts of the body. Regional means that the pain is typically localized to a particular body part. It could be pain in the low back. It could be shoulder pain. It could be knee pain or headache. It is not generalized or diffusely located over two or more quadrants of the body, typically. That is what's typically seen in fibromyalgia. Myofascial pain is caused by focally tender spots or knots in taut bands of skeletal muscle. These knots are called trigger points. What makes myofascial pain so unique is that these trigger points, while tender when palpated, do not in and of themselves spontaneously hurt. Rather, they refer typically deep aching pain to distant sites that often include non-muscular structures. So in this picture, the red and yellow splotches represent the clinical pain. So this is the pain the patient complains of, forehead pain, earache, perhaps cheek pain, pain in the inner canthus of the eye, maybe even chin pain. The ref, the, the cause of this pain is coming from the trigger points in the sternocleidomastoid muscle and these X's here represent the trigger points. Here is a representation of the referred pain coming from an upper trapezius muscle trigger point. Not that the pain pattern includes the back of the head, the angle of the jaw and the temple. The pain is also referred in and behind the eye. But myofascial pain is not limited to the head and neck region. We find trigger points in all muscles of the body. Here's a picture that illustrates pain coming from the gluteus medius and gluteus minimus muscles, and these trigger points tend to refer pain into the lower buttock area. Here is a picture of an, examples of knee and thigh pain coming from various parts of the quadriceps muscle. The blue dots are the trigger points and the areas in red represent what the patient is complaining of. Those are the areas where the patient has pain. So for example, here the patient may have persistent knee pain and yet there's nothing wrong with the knee. The guilty trigger point is way up here but the pain is here, and the disability is here. Here's another example of a different body part. This is the quadratus lumborum muscle referred pain patterns. The quadratus lumborum is found deep between the lower ribs and the back of the hip bone. It's also known as the joker of low back pain because it's so often involved in chronic back pain issues. Trigger points can be active or latent. An active trigger point is one where the referred pain is present and causing pain. For example, here in this picture we see a young man who is having a headache at work. His upper trapezius, and his chewing muscle here, have active trigger points causing his current headache pain. And then here is a video that illustrates the referred pain pattern from this particular, chewing muscle, trigger point. So you can see this trigger point tends to refer forward but also up and into the forehead region. Now here's the same person from the prior example where he has no headache pain. The same trigger points that were causing his pain the day before are now latent. They're not actively referring pain. Latent trigger points have the same characteristics as active trigger points, such as being located in a taut band of muscle and also being very tender when palpated. But unless stimulated or palpated, they are not at that moment in time causing any referred pain. With proper palpation however, we will see the referred pain emerge. And trigger points often vacillate between active and latent states, depending on how much mechanical or emotional stress is placed upon them. The referred pain pattern from any particular trigger point is essentially the same from person to person, and from time to time in the same person. Because trigger points refer pain in predictable patterns the site of the pain can easily be used in reverse to identify guilty trigger points. To that end, two textbooks detailing the pain referral patterns from almost all the muscles in the body, there's 200 pairs, were brilliantly compiled and detailed by Janet Travell and David Simons. Other textbooks and charts have also been published. Trigger points may also cause sensory, autonomic and motor symptoms in addition to referred pain. For example, other than pain, the area to which the pain is referred may become tender and or feel a little numb. If the pain is referred to into the head, it may feel funny to comb or brush the hair. If the pain is referred into the teeth, there may be concomitant tooth hypersensitivity or occlusive percussion may hurt. Heat and cold may be sensitive. Now, if we look at this picture, we see the pain referral pattern for the sternocleidomastoid muscle. The sternal head of the sternocleidomastoid muscle refers pain into these areas marked in red. But the sternal head may also cause autonomic disturbances such as blurred vision, ptosis or droopy eyelid, tearing and a runny nose. The clavicular division of the sternocleiddomastic muscle refers pain primarily into the forehead and into the ear. Concomitant autonomic symptoms, with the clavicular division trigger points include postural dizziness and imbalance, nausea, forehead sweating, and sometimes complaint of tinnitus or impaired hearing. Motor disturbances may include spasm of other muscles, weakness, loss of coordination, or loss of work tolerance of the muscle containing the trigger point. For example, grasping objects may become unreliable if there are weak hand muscles. Or there could be loss of forearm coordination. More importantly, when the pain from one trigger point is referred into another muscle, that muscle also tightens up. Over time this referred motor activity frequently results in the development of what we call satellite myofascial trigger points. And these satellite trigger points often then refer their own pain to a new place and confuse the clinical picture. Here, for example, we have a pic, a, an example of an upper trapezius trigger point that's referring pain in the usual pattern, back of the neck, angle of the jaw. And now this masseter muscle has a trigger point that is now referring new pain. So if the patient comes in with this pain complaint and the ma, masseter muscle trigger point is identified and treated, it will not resolve the pain because the actual nidus of the pain is coming from the upper trapezius muscle here. Further complicating the picture is that sometimes the upper trapezius trigger points are activated by lower trapezius trigger points. And this is the trigger point that needs to be treated, before this one will resolve, and before the masseter trigger point will resolve. Myofascial pain problems are exceptionally common. In fact, most of the time, myofascial pain is like a forest obscured by the trees. It is so common it goes unrecognized, and therefore is often missed as a diagnosis. In a university based general internal medicine practice, 30% of patients with a complaint of pain had myofascial pain causing their symptoms, but the primary care physician in charge of the patients had not made the diagnosis. The intensity of the pain was as great or greater than pain from other sources. This, this means that when a primary care doctor misses the myofascial trigger point diagnosis, the patient is likely to seek consultations with other specialists. If these specialists in turn miss the diagnosis, patients continue to have pain and ultimately end up in chronic pain management centers, where the diagnosis is also often ignored and the patient is primarily treated with medications. For example, in a university based orofacial pain practice, 55% of the patients had a myofascial pain as the primary diagnosis. Only 21% had an inflammatory temperomandibular joint disorder as the primary cause of pain. In another study that looked at almost 500 consecutive patients referred to a university-based orofacial pain clinic, 54.2% had myofascial pain due to trigger points as the primary diagnosis. Strikingly once patients did end up in an inpatient pain management program, 85% had myofascial pain as the primary diagnosis. This just illustrates the persistence of myofascial pain and the lack of recognition of this ubiquitous disorder by almost all primary care and specialty practitioners. So it's important to remember that myofascial pain is extremely common. It's like a forest obscured by the trees, and what, at the end of this module, I hope that you will be able to recognize myofascial pain disorders and treat them appropriately.
