D.O. have a unique tool that M.D.s do not utilize, osteopathic manipulative treatment.
Manipulation is thought to cause mechanical, neurophysiological, and psychological effects. Mechanically, manipulation can help restore normal positional relationships of vertebrae and also reduce disk protrusion. Neurophysiologically, it stimulates mechanoreceptor endings, which results in the inhibition of the presynaptic cells of the substantia gelatinosa at the level of the posterior horn, possibly resulting in a reduction of nociceptive activity. Manipulation also generates afferent input and activates Golgi tendon organs, which in turn diminishes fusimotor motor neuron discharge and relaxes intrafusal and extrafusal fibers. Manipulation is also thought to enhance the release of endorphins, cause an increase in the water content of collagenous and cartilaginous structures, and stimulate glycosaminoglycan synthesis, thereby increasing the pain threshold, cellular transport, and the lubrication of joint surfaces. Immobilization of joints or prolonged periods of reduced range of motion are thought to result in the formation of abnormal collagen crosslinks. Manipulation may lyse these abnormal crosslinks and enhance the formation of normal ones. Axoplasmic flow and the microcirculation of nerves are adversely affected by compression. Manipulation, by reducing compression, might enhance axoplasmic intraneuronal flow.
The "laying on of hands" or tactile nature of manipulation also has a strong psychological effect that is further reinforced by the interest and concern of the evaluator. Patients experience a sense of satisfaction and relief due, in part, to being touched and to a closer evaluation of their symptoms. In some cases, pain is reduced after a detailed musculoskeletal examination alone.
Osteopathic manipulative therapy contains over 100 different techniques or procedures. They are broadly grouped into 6 major types: high-velocity-low-amplitude (also called thrust or mobilization with impulse), muscle energy, counterstrain, myofascial release, craniosacral, and lymphatic pump techniques. High-velocity-low-amplitude, also known as mobilization with impulse, is a general type of manipulative treatment that involves a quick thrust over a short distance through what is termed a pathologic barrier. The movement is within a joint's normal range of motion and does not exceed the anatomic barrier or range of motion. With proper positioning of the patient, high-velocity-low-amplitude requires very little force and can be targeted to specific spinal segments. The goal of the treatment is to restore joint play or a desirable gap between articulating surfaces that permits free translational or gliding motion in addition to the usual angular motion. Of all the osteopathic techniques, high-velocity-low-amplitude most closely resembles the chiropractic technique and has the greatest number of contraindications. Contraindications include rheumatoid arthritic involvement of the cervical spine, carotid or vertebrobasilar vascular disease, the presence or possibility of bony metastasis or severe osteopenia, and a history of pathological fractures.
Muscle energy techniques involve the manipulator exerting an equal and opposite force to the patient's active force from a certain position and in a specific direction. The result is repeated isometric contractions with passive range of motion through the barrier after each isometric contraction. The goal is to increase joint mobilization and lengthen contracted muscles. Because no thrusting is done, this procedure has a very low likelihood of producing complications and can be used where high-velocity-low-amplitude is contraindicated. The mechanism of action is thought to be at least 2-fold: (1) through reciprocal innervation and (2) through the Golgi tendon reflex. When a stretch reflex excites one muscle, reciprocal innervation causes simultaneous inhibition of the antagonist muscle. The Golgi tendon organ reflex is an inhibitory reflex that can cause relaxation of a muscle when sufficient tension is placed on the Golgi tendon organ through either stretching or contracting the muscle.
When performing counterstrain, the manipulator places the symptomatic joint in the position of least discomfort while at the same time monitoring the degree of tenderness at a nearby tender point. This position of minimal discomfort is usually a position where the muscle is at its shortest length. The position is held for 90 seconds and the joint is slowly and passively returned to the neutral position.23 This prolonged shortening of the muscle causes shortening of both the intrafusal (muscle spindle) and extrafusal fibers. The gamma motor neurons then increase their firing rate to maintain tone in the muscle, and the muscle spindle fibers become hypersensitive. If the hypersensitive muscle is now lengthened too rapidly, a reflex overstimulation of the alpha motor neurons will occur. This sensory input travels to the higher centers of the central nervous system, which may misinterpret this input and respond with excessive gamma motor stimulation, maintaining the spasm. Reshortening the muscle allows the muscle spindle to shorten and resume normal firing. The central nervous system then resets its gamma motor neurons after about 90 seconds. The only contraindication for counterstrain is patient unwillingness or inability to cooperate.
Myofascial release techniques are similar to deep massage, but the hands of the manipulator are not merely slid along the skin surface. The goal is to stretch muscles and fascia to reduce tension. Traction is applied to the long axis of muscles. The mechanism of action is due in part to the Golgi tendon organ reflex and reciprocal innervation. Myofascial techniques can also be adapted to promote venous and lymphatic drainage.
Lymphatic pump techniques involve physical measures such as pectoral traction, postural drainage, effleurage, thoracic expansion, and rhythmic passive dorsiflexion of the feet in an attempt to enhance lymphatic return either by influencing negative intrathoracic pressure or mechanically assisting return of lymph from the lower extremities. Lymphatic techniques should not be performed in the presence or potential presence of metastatic cancer or active pulmonary tuberculosis or miliary tuberculosis.
Craniosacral therapy is based on the supposition that oscillatory motions of the cranial bones and sacrum exist. These movements are barely perceptible and are mediated through the tension of the various dural membranes such as the falx cerebri, tentorum cerebelli, and the dura along the entire spinal cord. Their amplitude and rate are thought to provide information about the patient's health and are thought to be influenced by the application of gentle pressure over specific areas of the cranium and sacrum. Craniosacral therapy is also thought to influence parasympathetic tone because the origins of parasympathetic division of the autonomic nervous system are located in the craniosacral regions.
Source: Archives of Family Medicine
