Myofascial Pain

The fascial system consists of the components of solid (muscles, bone, cartilage, and adipose tissue) and fluid (blood, lymph). The myofascial system comprises contractile muscle and connective tissue. The latter creates the shape of the muscle, penetrates the muscle, and orients the nerve and vascular endings; it has a thickening at the end of the contractile district that forms the insertions and origins of the muscle on the bone, thereby transmitting movement from the muscles to the bones to which they are attached. Within the myofascial system, the other components include the nervous, vascular, and lymphatic systems. Nervous tissue (axon and various afferents) and the resulting terminations are enclosed in multiple layers of fascia. Different tissues work in harmony to make up the myofascial continuum. The fascia integrates all the muscles within an interconnected network, and it would be incorrect to consider a muscular district as a separate entity. The myofascial system, if disturbed, can be a source of pain and functional limitation by creating vague symptoms that are not always clear and a challenge for the treating clinician. Myofascial pain is characterized by muscular trigger points (TP), which are hard, palpable nodules within the taut skeletal muscle bands. They are tender to palpation and movement, causing local and referred pain. There are 2 types of trigger points: active and latent. Active trigger points are associated with pain without movement or palpation. There are also latent trigger points, which are painful only to palpation. Myofascial pain syndrome is a disease with no standard management and surveillance protocol. The previous term to describe a TP was "fibrositis" (inflammation of the connective tissue covering the muscles). Myofascial trigger points are nodules in muscles that are tender to pressure and movement. TPs cause muscle weakness and limitation in the range of motion. Multiple TPs that have persisted for not less than a year confirm myofascial pain syndrome. Myofascial pain was first described by Guillaume de Baillou in 1600. In 1816, Balfour described this pain as associated with "thickenings" and "nodular tumors." In 1843, Froriep described the TPs as an accumulation of painful connective tissue. In 1904, Gowers wrote that the TPs were accumulations of inflamed connective tissue responsible for creating painful nodules. In 1919, Schade proposed the term "myogeloses" to describe the hard texture of the TP. In the mid-1900s, some scientists identified painful local areas in patients with myofascial pain, which produce pain when stimulated with hypertonic saline. Janet Travell was inspired by these studies, and together with Rinzler, coined the term "myofascial trigger points."