Myofascial trigger point

Myofascial trigger points, also known as trigger points, are described as hyperirritable spots in the skeletal muscle. They are associated with palpable nodules in taut bands of muscle fibers. They are a topic of ongoing controversy, as there is limited data to inform a scientific understanding of the phenomenon. Accordingly, a formal acceptance of myofascial 'knots' as an identifiable source of pain is more common among bodyworkers, physical therapists, chiropractors, and osteopathic practitioners. Nonetheless, the concept of trigger points provides a framework which may be used to help address certain musculoskeletal pain. Myofascial trigger points, also known as trigger points, are described as hyperirritable spots in the skeletal muscle. They are associated with palpable nodules in taut bands of muscle fibers. They are a topic of ongoing controversy, as there is limited data to inform a scientific understanding of the phenomenon. Accordingly, a formal acceptance of myofascial 'knots' as an identifiable source of pain is more common among bodyworkers, physical therapists, chiropractors, and osteopathic practitioners. Nonetheless, the concept of trigger points provides a framework which may be used to help address certain musculoskeletal pain. The trigger point model states that unexplained pain frequently radiates from these points of local tenderness to broader areas, sometimes distant from the trigger point itself. Practitioners claim to have identified reliable referred pain patterns which associate pain in one location with trigger points elsewhere. There is variation in the methodology for diagnosis of trigger points and a dearth of theory to explain how they arise and why they produce specific patterns of referred pain. Compression of a trigger point may elicit local tenderness, referred pain, or local twitch response. The local twitch response is not the same as a muscle spasm. This is because a muscle spasm refers to the entire muscle contracting whereas the local twitch response also refers to the entire muscle but only involves a small twitch, no contraction. Among physicians, various specialists might use trigger point therapy. These include physiatrists (physicians specializing in physical medicine and rehabilitation), family medicine, and orthopedics. Osteopathic as well as chiropractic schools also include trigger points in their training. Other health professionals, such as athletic trainers, occupational therapists, physiotherapists, acupuncturists, massage therapists and structural integrators are also aware of these ideas and many of them make use of trigger points in their clinical work as well. The term 'trigger point' was coined in 1942 by Dr. Janet Travell to describe a clinical finding with the following characteristics: Activation of trigger points may be caused by a number of factors, including acute or chronic muscle overload, activation by other trigger points (key/satellite, primary/secondary), disease, psychological distress (via systemic inflammation), homeostatic imbalances, direct trauma to the region, collision trauma (such as a car crash which stresses many muscles and causes instant trigger points) radiculopathy, infections and health issues such as smoking. Trigger points form only in muscles. They form as a local contraction in a small number of muscle fibers in a larger muscle or muscle bundle. These in turn can pull on tendons and ligaments associated with the muscle and can cause pain deep within a joint where there are no muscles. The integrated hypothesis theory states that trigger points form from excessive release of acetylcholine which produces sustained depolarization of muscle fibers. Indeed, the trigger point has an abnormal biochemical composition with elevated concentrations of acetylcholine, noradrenaline and serotonin and a lower pH. These sustained contractions of muscle sarcomeres compresses local blood supply restricting the energy needs of the local region. This crisis of energy produces sensitizing substances that interact with some nociceptive (pain) nerves traversing in the local region which in turn can produce localized pain within the muscle at the neuromuscular junction (Travell and Simons 1999).When trigger points are present in muscles there is often pain and weakness in the associated structures. These pain patterns in muscles follow specific nerve pathways and have been readily mapped to allow for identification of the causative pain factor. Many trigger points have pain patterns that overlap, and some create reciprocal cyclic relationships that need to be treated extensively to remove them. Practitioners do not agree on what constitutes a trigger point, but the assessment typically considers symptoms, pain patterns and manual palpation. Usually there is a taut band in muscles containing trigger points, and a hard nodule can be felt. Often a twitch response can be felt in the muscle by running your finger perpendicular to the muscle's direction; this twitch response often activates the 'all or nothing' response in a muscle that causes it to contract. Pressing on an affected muscle can often refer pain. Clusters of trigger points are not uncommon in some of the larger muscles, such as the gluteus group (gluteus maximus, gluteus medius, and gluteus minimus). Often there is a heat differential in the local area of a trigger point.