Myogenic pain in the back

According to modern statistics, the most common cause of back pain is muscle dysfunction.

In modern clinical medicine, two variants of myogenic pain (MB) are identified: myogenic pain with the presence of trigger zones and myogenic pain without trigger zones. If with the first option doctors are more or less familiar ("myofascial pain syndrome" - by the most common terminology), then the second option, as a rule, for most doctors is terra incognita. Meeting with her, in the overwhelming majority of cases - doctors make serious diagnostic, and therefore, therapeutic errors. The first variant is represented by classical myogenic pain, the second one is an interesting symptom complex called fibromyalgia (generalized muscle pain without (trigger zones) and, probably, the focal forms of this syndrome - tension headache (HDN) without trigger zones and pelvic floor syndrome (TDC) without trigger zones. "What we now call the headache of tension without trigger zones, in the 1980s, the largest specialist in the field of clinical myology, Professor Vladimir Janda, called" limbic hypertonia. "He converted The doctors are concerned that in this case there are no typical areas of muscular densification, and the whole muscle is evenly painful, and recommended not to waste time on manual treatment of this syndrome, but to treat functional disorders of the central nervous system (the emotional brain).

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Myogenic pain syndrome (MBS)

The most likely cause of the formation of the myogenic trigger zone (MTZ) is the violation of non-ionic effects on skeletal muscle fibers. The most common cause is abnormal modes of functioning of motoneuron with predominance of static loads, starting from school age. In the presence of somatic pathology or pathology of the musculoskeletal system (osteochondrosis of the spine, osteoarthritis of the spine) - reflex effects from the foci of pathological irrigation. In the pathology of the central nervous system or functional (stress factors, depression, anxiety, vegetative dystonia, etc.) - the violation of cerebral influences on motoneurons with subsequent functional disorders in the system of motoneuron-skeletal muscle fibers.

It is known that if the muscle contains a myogenic trigger zone, then its activity is inhibited, manifested by stiffness and weakness of the affected muscle. If the trigger zone is active, muscle activity slows down significantly. Thus, there is a reflex or conscious non-use of the muscle. The main consequence of non-use in muscle fibers is atrophy, especially slow-contracting fibers of type I, in addition, a small amount of fibers undergo necrosis, and the amount of connective tissue endomysia and perimisia increases. The contraction voltage and the tetanic stress decrease. There is also a trend towards the transformation of slow-shrinking fibers into fast-shrinking fibers, which is accompanied by changes in the isoforms of myofibrillar proteins. On the surfaces of unused fibers, acetylcholine receptors are spread beyond the neuromuscular synapse, the resting potential of the membrane is reduced. In the endings of the motor nerves, there are signs of degeneration in some areas and the formation of branches in others. Finally - after a period of non-use, the motor units can not be fully recruited. Then comes the pain that closes the vicious circle thrice: exacerbating the non-use of muscle, aggravating cerebral dysfunction, disrupting the motor stereotype.

The definition of the myogenic trigger zone given by J.Travell and D.Simons (1983) is generally accepted: it is the part of the increased irritability usually located within tight (packed) bundles of skeletal muscles or in the muscle fascia. It is painful during compression, it can reflect pain in its characteristic zones, cause vegetative and proprioceptive disorders. Pain increases with muscle tension, especially in the shortened state, with passive stretching of the muscle, with compression of the myogenic trigger zone, with prolonged finding of the affected muscle in a shortened state. In connection with the latter, a pathognomonic phenomenon of pain intensification is often observed in the clinic during the first movements after rest, but with the continuation of the motor activity, the pain significantly decreases or disappears. The pain increases with a slight cooling, which often affects the next laziness and is qualified by the patient as it "blew out the neck, lower back, etc.". Pain from the myogenic trigger zone decreases after a short rest, slow passive stretching of the affected muscle, using local heat, after mild movements. Clinically, the myogenic triggering zone is divided into active and latent, active myogenic trigger zones cause spontaneous pain, latent ones, forming an erection, are painful only when compressed, there is no spontaneous pain. Both forms can pass into each other. Very important is the fact that the force required to activate the latent myogenic trigger zone and provoke the pain syndrome depends on the degree of fitness of the affected muscle: the more it is hardy to exercise, the lower the susceptibility of its trigger zone to the activating influences.

Myogenic pain, reflected from the myogenic trigger zone, has a specific distribution for this muscle. Most often it is distributed within the same dermatome. Myotome or sclerotome, but can be partially reflected in other segments. Satellite myogenic trigger zones are formed in the muscles that lie in the zones of painful irradiation from other myogenic trigger zones or in irradiation zones from the affected internal organs (central sensitization). This is also a very important regularity.

The course of myogenic pain

Methods of treatment should be divided into two groups: methods of treating pain and methods for eliminating the trigger zone. The division is largely conditional, since most methods have both effects, but mostly affect one aspect or another.

A clinical fact is known that the better the muscle is trained, the more difficult it is to activate the trigger zone present in it. It is also known that myogenic pain decreases as the motor activity continues. It is known that in persons of physical labor the myogenic trigger zones are much less common than in persons with low physical activity. In our studies, we showed that the cause of the formation of the myogenic trigger zone is the violation of trophic effects of motoneuron on the muscle fiber, and the most physiological and effective method of eliminating the myogenic trigger zone and myogenic pain is the enhancement of neurotrophic effects through the voluntary activation of motor units in the mode of maximum recruitment. This is exactly the regime that empirically selected T. De Lorma (1945) for the rehabilitation of pilots after a prolonged imbalization of the knee joint.

In the presence of severe pain in a patient, the treatment of myogenic pain syndrome (MBS) is advisable to begin with the elimination or reduction of pain, because only after this it is possible to use the methods of kinesitherapy to eliminate the myogenic trigger zone. The most effective and economically justified method of treatment of acute pain is pharmacotherapy: NSAIDs (eg, diclofenac, lornoxicam) in therapeutic doses of 3-7 days in combination with tizanidine.

Novocainization of the myogenic trigger zone is described in detail in the guidelines for the treatment of myofascial trigeminal zones. It involves the introduction into the myogenic trigger zone procaine (novocaine) in the amount of several tenths of a milliliter into one myogenic trigger zone. Procaine (novocaine) is the least myotoxic drug among local anesthetic drugs and is most often used in practice. To achieve an analgesic effect, the needle should fall into the center of the myogenic trigger zone, as indicated by the local convulsive response of the muscle. "Dry" puncture of the myogenic trigger zone is also an effective method for reducing pain, if the needle exactly falls into the center of the myogenic trigger zone, as evidenced by the local convulsive response of the muscle. If the procedure is not accurate, the post-injection pain may be more pronounced than the actual myogenic pain. The same is true for injection of anesthetic. Improvement occurs immediately, or within 2 weeks. But in the range of 2-8 hours after the procedure, local soreness is experienced by 42% of patients who were injected with a local anesthetic and 100% of patients who underwent "dry" puncture. It is believed that the main therapeutic factor of both procedures is the rupture of the center of the myogenic trigger zone by the tip of the needle.

The most ancient and simple treatment is the use of heat (heat) to stop myogenic pain. There are many options for thermal therapy, ranging from the use of improvised tools and ending with instrumental methods. The mechanism of action of heat consists in modifying the sensory flow due to afferentation from the thermal receptors of the skin, which inhibits nociceptive afferentation at the level of the horn, and, in addition, improves microcirculation. This method is undoubtedly effective for reducing pain, but eliminating the causative factor (myogenic trigger zone) does not occur. Therefore, relapse of pain occurs rather quickly.

Another type of temperature action (cooling) is also used to reduce pain. Some authors consider it even more effective than warming. The mechanism of the procedure is the same as for warming, the duration of the effect is also insignificant. More effective is the combined method of stretching and cooling the muscle. Here there is a new important aspect - stretching. It is considered to be the main curative factor, and cooling by the auxiliary, besides it is considered necessary that the patient after the termination of the procedure conduct exercises, including the affected muscle in the maximum possible volume against the background of warming. Thus, the main sanogenetic moment of the method, called "irrigation by the coolant", is muscle stretching and kinesitherapy.

Ischemic compression of muscles (or pressures) is often used to treat a myogenic trigger zone of superficially located muscles. The essence of the procedure is to squeeze the myogenic trigger zone for about one minute to the pain tolerance threshold. The mechanism of the therapeutic action of the procedure is to create a "counterweight" nociceptive flow or hyperstimulation analgesia. From modern positions it can be added that under such intensive methods of influence destabilization of the pathological algic system also occurs, which facilitates its elimination by other methods. The history of the method goes back to ancient Oriental shiatsu and acupressure, where the technique of finger pressure is applied to specific points for harmonizing the circulation of chi energy. The effectiveness of the procedure r is quite high, but relapses of pain are also quite frequent. Recently, there have been reports that metabolic processes can be the basis for mechanical effects on the cell. It is assumed that the excitation of a hypothetical mechanoreceptor of a cell membrane can initiate a cascade of processes by activating G proteins, leading to a change in gene expression.

Classical massage is perhaps the most expensive method of treating the myogenic trigger zone for the costs of "man-hours" per patient. In addition, massage has one significant drawback - the masseurs do not wait for the relaxation of the tissue (in contrast to the specialists in manual medicine), which can cause reflex spasm of the muscles and pain. Exacerbation of pain after massage sessions is not uncommon in clinical practice. An improved version of classical massage is longitudinal massage, massage by JHCyriax. At the end of the course of treatment, pain often recurs, and treatment itself often requires a large number of sessions. Currently, the technique of passive stretching of soft tissues has been widely used under the name "myofascial release." Appeared a considerable number of specialists who claim to be authorship. It should be remembered that this technique is probably as old as the healing experience, and modern techniques are described by the above-mentioned authors.

From manual (manual) methods of therapy MB and MTZ the most physiological is the method of post-isometric muscle relaxation, proposed by KXewit (1981), the essence of which is the slow extension of the mouse in combination with its minimal isometric work. The method is highly efficient when properly executed, which requires considerable time. The effectiveness of the method is due both to the activation of the gate control of pain due to the enhancement of proprioceptive afferentation (along the fibers of Aa and Ab) and to the enhancement of the metabolic activity of the muscle fiber with passive stretching and isometric performance. In post-isometric relaxation, the mechanism of reciprocal spinal muscle relaxation can be used by alternating contraction of agonists and antagonists proposed by Knott M. (1964) and Rubin D. (1981). This method, called the method of proprioceptive relief, can cause severe pain in the muscles-antagonists because of their stress in the state of shortening.

Physiotherapy of myogenic pain includes the use of ultrasound, sinusoidally modulated currents, alternating magnetic field, laser radiation. There is a report on the high efficiency of direct repeated magnetic stimulation of the muscle in the treatment of myogenic pain.

Mobilization of own reserves of antinociceptive protection, activation of cortical descending projections, optimization of the motor stereotype is intensively developed by biofeedback specialists with good therapeutic results.

Of the latest advances in medicine, one should always mention the special form of botulinum toxin type A and its use for the treatment of myogenic pain. The toxin of botulism, irreversibly blocking exocytosis in the presynaptic end of the neuromuscular synapse, produces a chemical denervation of the mouse, which results in the elimination of the myogenic trigger zone and the cessation of myogenic pain. The method of treatment is simple in execution, does not require significant time. Only for the treatment of the myogenic trigger zone of deep muscles, such as stairways, iliac-lumbar, pear-shaped, requires x-ray control during the procedure. The effect of the drug lasts about 3-4 months. (minimally). The pain resumes after the reinnervation of the muscle fibers that formed the myogenic trigger zone. Disadvantages of the method are the high cost of botulinum toxin, the possibility of producing antibodies to it. However, if one compares the cost of the procedure for administering botulinum toxin with the cost of treatment with other methods for 3-4 months (the period of effectiveness of botulinum toxin), adding to this the cost of time spent on travel and receiving procedures, then the cost of botulinum toxin treatment is likely to be lower than traditional methods. At present, methods of treatment with botulinum toxin of the following types of myogenic and combined pain have been developed and successfully used: upper chest aperture syndrome, algic syndrome of shoulder adductors (shoulder-scapular periarthrosis), tension headache, migraine, cervicogenic headache, painful temporal dysfunction jaw joint, myogenic pain in the extremities (including pain caused by the myogenic trigger zone of the pear-shaped, ilio-lumbar muscles), pain in the myogenic tunnel neuro atiyah. Focal muscular dystonia, often accompanied by painful non-curable pain (spasmodic torticollis, facial hemispasm, paraspasm, blepharospasm), post-stroke spasticity with pain, is effectively treated with botulinum toxin, which is the only effective drug in these situations.