Myofascial Trigger Points
Highlights
- A myofascial trigger point is a hyperirritable spot, usually within a taut band of skeletal muscle, which is painful on compression and can give rise to characteristic referred pain, motor dysfunction, and autonomic phenomena (View Highlight)
- A myofascial trigger point is a hyperirritable point in skeletal muscle that is associated with a hypersensitive palpable nodule (View Highlight)
- When the trigger point is pressed, pain is caused and produces effects at a target, the zone of reference, or referral zone [3|3], [4|4]. This area of referred pain is the feature that differentiates myofascial pain syndrome from fibromyalgia. This pain is reproduced reliably on palpation of the trigger point, despite the fact that it is remote from its source of origin. This referred pain rarely coincides with dermatologic or neuronal distributions, but follows a consistent pattern (View Highlight)
- Trigger points may develop after an initial injury to muscle fibers. This injury may include a noticeable traumatic event or repetitive microtrauma to the muscles. The trigger point causes pain and stress in the muscle or muscle fiber. As the stress increases, the muscles become fatigued and more susceptible to activation of additional trigger points. When predisposing factors combine with a triggering stress event, activation of a trigger point occurs. This theory is known as the “injury pool theory” (View Highlight)
- It was hypothesized that a myofascial trigger point locus is formed when a sensitive locus, the nociceptor, and an active locus—the motor endplate—coincide (View Highlight)
- The diagnosis of myofascial pain syndrome, as defined by Simons and colleagues [12|12], relies on eight clinical characteristics (View Highlight)