Manual Osteopathy and Somatic Dysfunction

Somatic dysfunction, or ‘osteopathic lesion’, has been considered a central concept of the theory and practice of osteopathy for over a hundred years. The term represents a single clinical entity that is diagnosed exclusively by osteopaths, and it can impact function, general health, and predisposes the body to disease. It is proposed to be a reversible, functional disturbance, which can be specifically and appropriately addressed using osteopathic manual treatment (OMT). Somatic dysfunction may be encountered in a variety of medical conditions, including musculoskeletal disorders and systemic diseases, that are managed by manual osteopaths.

Somatic dysfunction has been defined as ‘impaired or altered function of related components of the somatic (body framework) system: skeletal, arthrodial, and myofascial structures, and related vascular, lymphatic, and neural elements.’ The term can be used  broadly to refer to dysfunction of a group of tissues or a region, or used more specifically for dysfunction of a single body part.

Somatic dysfunction is not synonymous with spinal pain, and palpable signs of dysfunction may be detected in symptomatic and asymptomatic individuals. It has been proposed that the presence of somatic dysfunction in asymptomatic individuals can create biomechanical and neurological disturbances which predispose the individual to further pain and other health complaints. 

Somatic dysfunction can be detected by palpation using four cardinal clinical signs: tenderness, asymmetry, range of motion abnormality, and texture changes of body tissues. The mnemonic TART or ARTT is commonly used as a memory aid for these clinical signs. At least two of these signs must be present for a diagnosis of somatic dysfunction. Most osteopaths also consider motion restriction an important feature of somatic dysfunction.

Somatic dysfunction is likely caused by tissue injury and degenerative changes. Tissue factors may include either macro-trauma or repetitive micro-trauma of the joint capsule, periarticular soft tissues, or annulus of the disc, and this can lead to inflammation and activation of nociceptors (pain receptors). Nociceptive-driven functional changes may further produce alterations in tissue texture and pain sensitivity, two of the cardinal features attributed to somatic dysfunction by osteopaths. Additionally, degenerative changes will also contribute to tissue texture and range of motion changes and to activation of nociceptive pathways.

Somatic dysfunction is commonly described as being acute or chronic, and these stages likely relate to acute tissue inflammation or long-term degenerative change, with both potentially accompanied by neurological and functional changes. In the acute stage, tenderness is most easily explained by nociceptor activation and peripheral sensitisation following tissue injury. In the chronic term, nociceptive-driven neuroplastic changes in the dorsal horn and higher central nervous system can lead to long term pain and tenderness.

In summary, the osteopathic concept of somatic dysfunction is based on biomedical and biomechanical models, where physical clinical findings represent a functional abnormality and subsequent manipulative treatment restores the function. The structural assessment findings associated with somatic dysfunction represents a fundamental and uniquely osteopathic approach to clinical practice. Such findings can guide osteopathic manual treatment (OMT), which is the therapeutic application of manually guided forces to improve physiological function and to restore homeostasis that has been altered by somatic dysfunction.