The prevalence of myofascial pain and dysfunction is not well known. What data does exist on the topic hints at the fact that myofascial pain and dysfunction is more prolific than once thought.
Introduction
According to the growing evidence, myofascial trigger points are prevalent. Exact statistical figures regarding those who are afflicted with myofascial pain and dysfunction are difficult to obtain. Travell and Simons1 believe myofascial ailments are prevalent enough to have a direct impact on "nearly everyone's life at one time or another."
At this point, a compelling question needs to be asked: "If myofascial ailments are believed to be so prevalent, then why is valid and reliable epidemiologic information so hard to come by?" Much of the data on this topic has been published under a diverse assortment of names. This diversity of terms has done more to confuse and confound doctors. In effect, two doctors would be unaware that they were looking at the same clinical entity by virtue of the different names being applied to it. To this day, as a result of this historical confusion of terms, many physicians are wholly unfamiliar with myofascial disorders. Similarly, myofascial disorders are foreign to those scholars and athletes actively involved in sport.
Myofascial trigger points can be broadly classified into two categories: latent and active. Latent myofascial trigger points are clinically silent for pain, causing muscular stiffness, weakness, and restricted range of motion.
Active myofascial trigger points share all the attributes of their latent counterpart except for the fact that they actively produce pain. According to Travell and Simons1, latent myofascial phenomena are "far more common than active ones."
Much has been written on the pain generated by myofascial disorders. Myofascial pain is unique in that it is typically referred or projected to a distant region of the body. Knowledge of the referred pain and the distinctive patterns that they exhibit is useful in locating the pain-producing trigger point. This is facilitated since each muscle and their trigger points refer pain in consistent and distinctive patterns.
Latent, as well as active myofascial trigger point phenomena arise as a result of acute overload, overwork fatigue, direct trauma, and by chilling.1 These same mechanisms can transform latent trigger points into active, pain-referring trigger points. Travell and Simons1 have noted that the "signs and symptoms of myofascial trigger point activity long outlast the precipitating event." When a muscle is injured or overworked and adequate rest is not given, the muscle simply "learns" how to avoid further insult. This is accomplished by limiting the forces it generates and by staying taut enough to limit its ability to lengthen through passive stretch. Much of the "dysfunction" that occurs is believed to be modulated by muscle spindles and nociception.
Little has been written on the more ubiquitous but latent myofascial disorders. Since latent trigger points are not painful, they receive very little attention, both in clinical practice and in the research literature. This, I believe, will change as we learn more about how latent myofascial trigger points effect athletic performance.
The dysfunctions that characterize latent myofascial trigger points are limited range of motion and weakness. Herein lies their significance in the realm of sport. An athlete, in order to perform at maximum efficiency and effectiveness, must possess exceptional flexibility and strength. High performance athletes understand the value of strength and flexibility in achieving greatness.
An athlete's fitness level relates directly and positively to his performance. It is the wise athlete who recognizes this and trains for the appropriate fitness level. Fitness has three dimensions to it: strength, flexibility and endurance. Muscles harboring latent myofascial trigger point phenomena are known to lack strength and flexibility.1 It is conceivable that they lack an endurance component as well. Individual or groups of muscles such as these can be said to lack an adequate level of fitness necessary to perform optimally.
When an athlete's overall fitness is appropriate for his sport and level of competition, he will perform well. If this same athlete is harboring a latent myofascial trigger point in a key muscle or muscle group, then he will not perform as well as he might otherwise. Latent myofascial trigger points in key muscles may hamper the athlete's performance. These latent trigger points present themselves as myofascial barriers to peak athletic performance.
Discussion
Sudden weakness of a muscle and limited range of motion of a joint can have a devastating effect on athletic performance. Latent trigger points in the low back in a golfer can limit both his preparatory back-swing and his ability to generate sufficient force upon impact of the club head and ball. Latent trigger points in the soleus muscle of a sprinter can result in a decreased ability to produce forceful plantar flexion to propel the runner to the finish. Consider a 26-year-old hockey enthusiast with pain in the left groin. A hockey injury six years prior to his presentation to my office left him with "too much pain to skate." During that time he was largely unable to participate in hockey. In addition, he complained that when he walked or attempted to skate, his left leg felt "weak" as if it were going to "give way" and not support him. An adductor magnus trigger point was identified and treated using the spray and stretch technique of Travell and Simons.1,2
Six sessions of spray and stretch were required to take the trigger point from an active state to a latent state. At that point the patient experienced left groin "weakness" in the absence of pain. Repeated attempts by the patient to jog or skate resulted in weakness and feelings of "tiredness" and fatigue in the left groin. An additional 12 treatments returned him to jogging, tennis, golf, and skating. Today, this athlete is fully recovered and happily pursuing a career as an attorney, while playing adult league hockey in the evenings.
This example is typical of an injury seen by sports chiropractors and sports physicians alike. What it illustrates is the phenomena of myofascial pain and dysfunction playing a role in sports injury and as a barrier to sports participation. The initial injury led to the pain and dysfunction, but what if there is no specific history of injury? What if an otherwise normal athlete is not performing as expected?
References
- Travell JG, Simons DG: Myofascial Pain and Dysfunction: The Trigger Point Manual. Vol 1, Baltimore, Williams & Wilkins, 1983.
- Travell JG, Simons DG: Myofascial Pain and Dysfunction: The Trigger Point Manual. Vol 2, Baltimore, Williams & Wilkins, 1992.
Andrew S. Bonci, B.A., D.C.
Tuckahoe, New York