What can lead to persistent pain in the presence of a trigger point (TP)?

The presence of chemicals of pain plays a significant role in the development and persistence of pain associated with trigger points. Trigger points are hyperirritable spots in skeletal muscle that can be associated with pain due to various biochemical processes. When these trigger points are active, they release various inflammatory mediators, such as substance P, bradykinin, and leukotrienes, which can sensitize nerve endings and contribute to the sensation of pain. This biochemical environment can perpetuate a cycle of pain and dysfunction, making the pain more persistent.

In contrast, the absence of pain chemicals would likely lead to reduced pain perception, and a reduction of nociceptive signals would also lessen the sensation of pain. Immobilization of muscles may lead to weakness or deconditioning but would not necessarily be directly linked to the presence of trigger points or chronic pain in the same biochemical context. Thus, the presence of pain chemicals is a critical factor that helps explain why persistent pain can occur with trigger points.