The use of manipulation is as ancient and widely practiced among various cultures as the field of medicine itself. The first documented writings on manipulation can be traced back to Greece, where Hippocrates (460–385 BCE) described using gravity and traction techniques to treat scoliosis.¹ Other notable figures in medicine also referred to the use of manipulative procedures, such as Galen, Celisies, and Oribasius.² Manual treatment was developed further in Europe by generations of “bonesetters,” manual practitioners who passed on the art of technique from one family member to another. The bonesetter’s approach evolved as medically trained practitioners moved toward more pharmacological approaches.³ Wharton Hood, MD, a 19th-century British practitioner, devoted a great deal of time to studying the procedures of bonesetters. He even published papers in The Lancet in 1871 that reported the effectiveness of manipulation in the relief of musculoskeletal problems.⁴

At the turn of the 19th century and even a bit beyond, turmoil was present in the medical community and, in spite of huge strides in scientific investigation, medicine had changed little.^1,2 One individual eventually would take a radically different path to healing—a man called Andrew Taylor Still.

Still (1828–1917) was greatly influenced in his pursuit of medicine by his father, a physician and Methodist minister. In the mid-1800s, a person could become a physician through an apprenticeship. Still likely attended only one seminar of formal medical education, as he believed it uninspiring. He seemed well aware that the current medical treatments, including bloodletting, could inflict more harm on patients than if they were left alone.¹ His disenchantment with the medical practices of the day came to a culmination when he lost three of his children in a single outbreak of spinal meningitis.^1,5 In April 1874, he coined the term “osteopathic medicine.”²

Still believed that rather than treating only the symptoms of a disease with harmful agents such as alcohol, mercury, and large doses of opium, a doctor should attempt to discover the cause of the disease itself. He originated the concept of wellness and developed principles of proper exercise and diet to prevent disease.⁶ The best summary of this philosophy is expressed in Still’s own words: “To find health should be the object of the doctor. Anyone can find disease.”⁷ He also noted that circulation was of the utmost importance, proclaiming that “the artery is the father of the rivers of life, health, and ease, and its muddy or impure water is first in all disease.”⁸

It is unclear when and how Still added manipulation to his philosophy of osteopathic medicine. Interestingly, he did not write a book on manipulative techniques. His writings instead focused on osteopathic philosophy, practice, and principles.² It was not until 1879 that he became known as the “lightning bonesetter.”²

As Still became more successful and well known, both nationally and internationally, many individuals came to him to learn. This led to the establishment of the first college of osteopathic medicine at Kirksville, Missouri, in 1892.² The field of osteopathic medicine has grown substantially since then. During the 2014–2015 academic year, the American Osteopathic Association Commission on Osteopathic College Accreditation accredited 31 colleges of osteopathic medicine offering instruction at 45 teaching locations in 30 states.⁹ Osteopathic medical students study the same material as their allopathic colleagues and work side by side in the clinical and research worlds, but they learn and work through the osteopathic philosophy, with an added realm of using manual medicine.

Osteopathic philosophy emphasizes the following four principles:

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  The human being is a dynamic unit of function.

  
  
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  The body possesses self-regulatory mechanisms that are self-healing in nature.

  
  
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  Structure and function are interrelated at all levels.

  
  
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  Rational treatment is based on these principles.¹⁰

Related osteopathic principles for patient care also have been proposed, stating that the patient is the focus of health care and that the patient has the primary responsibility for his or her health.¹¹

Manipulation Definitions

“Manipulation” has been described as the therapeutic application of manual force. This is in comparison to “manual medicine,” which is described as the skillful use of hands to diagnose and treat structural and functional abnormalities in various tissues and organs throughout the body, including bones, joints, muscles, and other soft tissues as an integral part of complete medical care. Although used interchangeably, manual therapy is used by nonphysician practitioners.¹⁰ Commonly, the term “osteopathic manipulative treatment (OMT)” is used, which is the therapeutic application of manually guided forces by an osteopathic physician. The purpose of OMT is to improve physiologic function and support homeostasis that has been altered by somatic dysfunction.¹⁰ Therefore, OMT is used to treat “somatic dysfunction,” which is defined as impaired or altered function of related components of the somatic (body framework) system: skeletal, arthrodial, and myofascial structures and their related vascular, lymphatic, and neural elements.¹⁰

Somatic Dysfunction

The diagnosis of somatic dysfunction includes searching for objective evidence of tissue texture changes, restricted range of motion, and asymmetry with a hands-on, palpatory approach. Tenderness is also included as the sole subjective finding. These findings can be summed up by the mnemonic “TART,” which is listed in Table 96–1, along with further classification of acute versus chronic palpatory findings of somatic dysfunction.²

Barrier Concepts in Structural Diagnosis

To diagnose and choose the best type of OMT technique in the treatment of somatic dysfunction, the barrier concept first must be understood. The term “barrier concept” refers to the movement capabilities of a joint during normal and restricted motion. Although joints typically have more than one direction of movement, for descriptive purposes, one joint and one direction of movement will be described (i.e., axial rotation of C1). The neutral position of a joint is that of a nondysfunctional joint at rest, with equal myofascial pulling forces in all directions. When a healthy joint is actively moved, the end range of motion is referred to as the “physiologic barrier.” During passive testing of a joint, the furthest motion obtained is called the “anatomic barrier.” Motion beyond the anatomic barrier will cause structural damage to that joint. The range between the physiologic and anatomic barrier of motion in which passive ligamentous stretching occurs before tissue disruption is referred to as the “elastic barrier.”

A restrictive barrier occurs before the normal physiologic barrier and is caused by somatic dysfunction. A pathologic barrier, on the other hand, is a permanent loss in normal range of motion, such as with a muscle contracture or joint fusion. OMT is used to treat restrictive barriers, which can be found in many different tissues, including skin, fascia, muscle, ligament, joint capsule, and joint surfaces. It is important to evaluate the quality of movement, as well as the feel at the end point of motion (i.e., hard or soft), as this will direct which type of OMT intervention will best help to restore maximal physiologic movement.^2,12

A variety of techniques exist for restoring symmetry and physiologic range of motion. Broadly, techniques can be divided into direct or indirect techniques. A direct type of technique engages the restrictive barrier, with eventual movement of the tissues, joints, or both by the clinician through this barrier. With an indirect technique, the movement of tissues, joints, or both by the clinician occurs away from the restrictive barrier in the direction of freedom. Next, treatment can be divided further, into active versus passive treatment. In active treatment, the patient will assist in the treatment, usually in the form of isometric contraction. In passive treatment, the patient is completely relaxed and without movement or muscle activation. Specific treatment types and their respective subcategories are listed in Table 96–2.

Muscle Energy

Dr. Fred L. Mitchel is acknowledged as the father of muscle energy, although the technique was first used in the neck and around the orbits by Dr. T. J. Ruddy in the 1940s and 1950s.² Mitchel defined “muscle energy” as when the patient uses his or her muscles on request from a precisely controlled position in a specific direction against a distinctly executed counterforce.¹³ Muscle energy is described as an active technique because the patient contributes the corrective force. Although the patient actively pushes away from the restrictive barrier, after relaxation, the clinician moves the segment further into the direction of the restrictive barrier. Therefore, it falls under the classification of a direct technique. Muscle energy can be used to lengthen a shortened and contracted muscle, strengthen a weak muscle or group of muscles, reduce edema by active contraction, and mobilize an articulation with restricted mobility.²

The physiologic basis of the muscle energy technique is debated and beyond the scope of this discussion. Classically, it is taught that stimulation of alpha motor neurons causes muscle contraction, which shortens the muscle spindle, thus resetting it to a new resting length. The muscle spindle, therefore, is able to change the resting length of the extrafusal muscle fibers.¹⁴ Simply put, after an isometric contraction, a hypertonic muscle can be passively stretched to a new length.⁷ It has been proposed, however, that the explanation of muscle energy may actually lie in the biomechanics of connective tissue. An isometric contraction may impart stretch to the parallel connective tissue elements, leading to a stretch beyond that normally activated by a simple passive stretch.¹⁵

There are two basic types of muscle energy techniques:

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  Isometric: A hypertonic muscle is activated with an isometric contraction. After the contraction, the hypertonic muscle can be stretched to a new length.

  
  
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  Isotonic: Contracting an agonist muscle will inhibit its antagonist so it may be stretched to a new length.

The technique is typically carried out using an isometric contraction. The first step is to move the dysfunctional segment toward the “feather edge” of the restrictive barrier. The patient then isometrically activates in the opposite direction of dysfunction with gentle force, which is held for 3 to 5 seconds. The patient is then asked to completely relax or stop contracting. After waiting for 2 to 3 seconds (the postisometric relaxation period), the dysfunctional segment is moved to the new barrier and the process is repeated. Moving directly to a new barrier after contraction instead of holding a prolonged static stretch has been shown effective.¹⁶ The utilization of an isometric contraction of short duration (5 s) has been shown to be equally or more beneficial when compared to a long duration (20 s) contraction.¹⁷

High-Velocity Low-Amplitude (HVLA)

“High-velocity low-amplitude (HVLA)” has been defined as a technique that employs a rapid, therapeutic force of brief duration that travels a short distance within the anatomic range of motion of a joint, and that also engages the restrictive barrier in one or more planes of motion to elicit release of restriction.¹² HVLA is a direct and passive technique that is most effective when applied to a single joint with a “hard end feel.”² If a softer and more “elastic end feel” is present in the joint, a different technique is likely to be more appropriate. The method of thrust delivery cannot be understated, as using a low-velocity thrust with a large range of motion is hazardous to the patient. A model by Brodeur describes the sudden joint distraction as occurring in a shorter time than that required to complete the stretch reflexes of the periarticular muscles.¹⁸ Hence, using a fast-thrusting technique to avoid muscle tension around the targeted joint is crucial. The movement at the joint is likely only about one-eighth of an inch.²

The sound generated by joint manipulation has been classified in various ways throughout the osteopathic medical literature. It has been referred to as an “articular crack,” “articular pop,” “clunk,” “joint click,” “snap,” and “thud.”²⁰ Most commonly, the act of HVLA on a specific joint is referred to as an “articular release,” where the joint is moved past its physiologic (but not anatomic) barrier, resulting in functional change and increased joint motion.²⁰

An articular release may or may not be accompanied by an audible noise. Although the exact mechanism of the sound during articular release remains unknown, there are several theories. The predominant theory remains the cavitation model, originally proposed by Unsworth in 1971. A rapid increase in joint volume allows the release of carbon dioxide as gaseous bubbles into the joint cavity. The subsequent flow of synovial fluid into the low-pressure regions of the cavity collapses the gas bubbles, producing the audible sound.²¹

Strain-Counterstrain

“Strain-counterstrain” is a passive and indirect technique that revolves around the diagnosis and treatment of tender points. The technique was developed by Lawrence Jones, DO, and was initially reported in the literature in 1964 as spontaneous release by positioning.²² Tender points are described as small (<1 cm), edematous, and round areas of nonradiating sensitivity located in muscle, tendon, ligament, or fascial tissue.²³ After identification of a tender point, the treatment involves positioning the patient in a way that decreases the pain level, followed by holding that position for 90 seconds while lightly monitoring the tender point. Finally, a slow, operator-dependent return to normal position is crucial for success² (Fig. 96–1).

The most common explanation for the effects of strain-counterstrain is the “proprioceptive theory,” which involves aberrant neuromuscular activity between agonist and antagonist muscles. A rapid stretching injury stimulates muscle spindles, causing reflexive agonist muscle contractions that resist further stretching. However, this agonist contraction causes rapid lengthening of the antagonist muscle, thereby also exciting its muscle spindles. Neuromuscular imbalance ensues due to opposing muscle spasms from ongoing spindle excitation, resulting in hypertonic myofascial tissue and restricted motion.^12,23–25 By passively shortening the dysfunctional agonist muscle long enough through the strain-counterstrain technique, normal muscle spindle activity is allowed to return. Once agonist muscle spindle activity is reset, antagonist muscle spindle activity can return to the resting state, relieving aberrant neuromuscular activity and restoring normal function.^23,26

Myofascial Release

Prior to discussing myofascial release (MFR), a greater understanding of the fascia must be established. A. T. Still spoke of fascia as vital for growth, support, and nourishment. He described fascia as omnipresent and that which “sheathes, permeates, divides, and sub-divides every portion of all animal bodies; surrounding and penetrating every muscle and all its fibers.”⁷ The modern definition of fascia has been troublesome, however, due to its widespread and varied nature. As proposed by the Fascia Research Congress, a broad definition of “fascia” is “a soft tissue component of the connective tissue system that permeates the human body.” With a broader definition, fascial tissues are seen as one interconnected tensional network that adapts its fiber arrangement, length, and density according to local tensional demands.²⁷

A closer look at fascia has shown it to have significant sensory properties. The thoracolumbar fascia has been found to contain free nerve endings and sympathetic fibers,²⁸ along with the Ruffini and Pacini²⁹ mechanoreceptors. These findings suggest that fascia has a proprioceptive role, along with being a pain generator. Its sensory role, along with its interconnected organization, suggest that fascia serves as a bodywide mechanosensitive signaling system.³⁰ Within this complex system, somatic dysfunction arises and is very amenable to MFR.

MFR involves specifically guided, low-load, and long-duration mechanical forces to manipulate the myofascial complex with the intent to restore optimal length, decrease pain, and improve function.³¹ Due to the close interconnectedness of the fascial system, restriction in one area of the body can cause dysfunction at a distant location. Performing MFR is a passive technique that can be achieved through either direct or indirect force. Direct MFR engages a tissue-restrictive barrier, loads the tissue with a constant force, and waits for the tissue to release. Indirect MFR guides restrictive tissues along the path of least resistance until free movement is achieved.¹⁰

Performing the technique requires continual palpatory feedback, along with very slow and gentle pressure. If too much force is applied too quickly, the fascia will respond with defensive tightening. A great exercise to drive home this concept involves placing one’s fingers into a mixture of cornstarch and water. If the fingers are placed into the mixture aggressively, they will bounce off the surface. However, if slow, gentle pressure is applied, the fingers will sink deeply into the mixture. Likewise, the myofascial system responds best to slow, gentle pressure. (Fig. 96–2).

Overall, there is a paucity of large-scale, high-quality studies looking at MFR as a treatment intervention.³² Some of the reasons are the varied palpatory and treatment skills of the physician, the subjective patient-clinician interaction, and the view of MFR as an art form.³³ However, basic science knowledge of fascia is increasing, as is an understanding of the mechanisms of MFR. For example, human fibroblasts have been looked at in vitro under varied biophysical strains (10%–30% of the resting length). The fibroblasts were found to respond by secreting inflammatory cytokines, undergoing hyperplasia, and altering cell shape and alignment.³⁴ Another in vitro study demonstrated that using a simulated, indirect, OMT-like release of strain for 60 seconds was able to reverse inflammatory effects in cells that have been repetitively strained. More recent in vitro evidence has shown that its effect on the extracellular matrix may promote wound healing.³⁵

Physiatrists are trained to holistically evaluate the function of a patient. Due to the continuity of fascia throughout the body, the repercussions of a focal fascial restriction may actually lead to biomechanically inefficient global function.³⁶ This may become especially important in the evaluation and treatment of patients with disabilities due to having higher energy demands with daily functional activities. Therefore, all efforts to diminish body energy demands should be employed, including the treatment of fascial restrictions.

Other OMT Techniques

There are several other specific techniques used in osteopathic manipulation; however, these are beyond the scope of this chapter. Other such techniques include craniosacral, balanced ligamentous tension, facilitated positional release, lymphatic drainage, articulatory, and Still technique.

Just as with any other medical procedure or treatment, spinal manipulation is not without risk. As a general rule, manipulation should not be performed over areas of acute infection, skin breakdown, or recent surgical sites. Patient refusal is a definite contraindication. Most of the worrisome adverse events are with regard to HVLA, specifically of the cervical spine. Adverse events from cervical spine manipulation are rare, but they do occur. Prior to performing HVLA on either the cervical, thoracic, or lumbar spine, a proper diagnosis of motion restriction should be made, along with a thorough history and physical exam to rule out any potential contraindications. Prior to thrusting, the restrictive barrier should be fully engaged.

An article in 2012 reviewed the literature from 1950 to 2010 and found 134 case reports of adverse events after cervical spine manipulation. Arterial dissection was the most common adverse event reported (37.3%). Other events included disc herniation (18.7%), stroke (13.4%), and vertebral dislocation or fracture (6.7%). The most common postmanipulation symptoms were weakness, paresthesia, and increased pain. Chiropractors were involved in the majority of cases (69.4%), likely because cervical spine manipulation is the most common treatment used by chiropractors and is performed with greater frequency by them than by other providers. Osteopathic physicians were involved in substantially fewer cases (8.2%), followed by physical therapists (3.7%). Further evaluation into the specific cases showed that 19.4% of cases were categorized as inappropriate, 44.8% as preventable, and 9% as both inappropriate and preventable. Half of the cases that were deemed preventable were found to have preexisting conditions in the cervical spine, such as severe spondylosis, osteoporosis, rheumatoid arthritis, ankylosing spondylitis, and cervical stenosis.³⁷ Another study looking at 40 adverse events with cervical spinal manipulation found two consistent problems. First, a proper diagnosis of motion restriction was not made. Second, the restrictive barrier was not properly engaged prior to thrust delivery, resulting in a high-amplitude, high-velocity thrust.³⁸ An improper diagnosis and an improperly engaged barrier increase the chance of injury. The decision to perform HVLA, especially on the cervical spine, should be highly individualized and only performed by experienced, confident practitioners.

Translation of Osteopathic Manipulation to Modern Science

Key aspects of the osteopathic philosophy and treatment paradigm include body unity and interconnectedness. Research has shown that a model called “biotensegrity” can demonstrate this close structure-function relationship at all levels throughout the human body. However, we must first discuss the term “tensegrity,” which is an architectural principle put forth by Buckminster Fuller in the 1960s and describes how structures are stabilized by continuous tension with discontinuous compression (tensional + integrity = tensegrity).³⁹ David Robbie, MD, proposed in 1977 that the human musculoskeletal system could be viewed as a tensegrity system.⁴⁰ Shortly afterward, Stephen Levin, MD began viewing tensegrity as the overall biological support system for the body and coined the term “biotensegrity.”⁴¹ According to the theory, bones are thought of as discontinuous compression struts, while the muscles, tendons, and ligaments are the tension elements. Taking this theory to another level, the work of Donald Ingber, MD, PhD, has demonstrated that cells function as tensegrity structures.^42,43 Furthermore, work has been done to show that organs, tissues, and even molecules can be viewed in the same way.⁴⁴

Bringing us closer to the clinical application of these concepts is “mechanotransduction,” a process whereby cells convert mechanical stimuli into biochemical responses. Mechanical loading on the outside of a cell pulls on integrin proteins, which are connected to the cell’s cytoskeletal elements, which in turn directly communicate with the nucleus. The integrins also activate biochemical signaling agents, which affect gene expression in the nucleus. When used in a therapeutic aspect, such as exercise to promote tissue remodeling, the term “mechanotherapy” is suggested.⁴⁵ These principles of biotensegrity and mechanotherapy offer an explanation as to how forces applied through osteopathic manipulation not only have a global effect on the gross musculoskeletal system, but actually produce changes at the cellular level, and possibly even lead to changes in gene expression. Further research is still needed in this exciting area.

Osteopathic Assessment and Treatment of the Cervical Spine

The cervical spine can be divided into upper and lower cervical complexes. The upper cervical complex consists of the occipitoatlantal (OA; C0–C1), and the atlantoalaxial (AA; C1–C2) joints. The lower cervical complex consists of the C3–C7 segments.