Latent Myofascial Trigger Points

Abstract

A latent myofascial trigger point (MTP) is defined as a focus of hyperirritability in a muscle taut band that is clinically associated with local twitch response and tenderness and/or referred pain upon manual examination. Current evidence suggests that the temporal profile of the spontaneous electrical activity at an MTP is similar to focal muscle fiber contraction and/or muscle cramp potentials, which contribute significantly to the induction of local tenderness and pain and motor dysfunctions. This review highlights the potential mechanisms underlying the sensory-motor dysfunctions associated with latent MTPs and discusses the contribution of central sensitization associated with latent MTPs and the MTP network to the spatial propagation of pain and motor dysfunctions. Treating latent MTPs in patients with musculoskeletal pain may not only decrease pain sensitivity and improve motor functions, but also prevent latent MTPs from transforming into active MTPs, and hence, prevent the development of myofascial pain syndrome.

Dry needling — peripheral and central considerations

“…229 Inactivation of latent trigger points with dry needling or with manual pressure techniques may prevent the development of active trigger points and reduce and in many cases remove their nociceptive input, normalize the synaptic efficacy, and reduce peripheral and central sensitization. 60 After eliciting a local twitch response with a needle, SP and CGRP were significantly reduced in active trigger points, which corresponds with the clinically observation of an immediate decrease in pain and local tenderness after the inactivation of a trigger point with dry needling. 10,11 We already mentioned that dry needling can restore range of motion and muscle activation patterns, 5,8,9 and reduce local, referred, and widespread pain.…”

“…58,59 Several studies have shown, however, that latent trigger points do provide nociceptive input into the dorsal horn even though they are not spontaneously painful. [60][61][62][63][64][65][66] It is not entirely clear why this occurs.…”

Spatial Pain Propagation Over Time Following Painful Glutamate Activation of Latent Myofascial Trigger Points in Humans

“…38 Similar occurrence of referred pain following intramuscular injection of glutamate into latent MTPs and non-MTPs suggests that the dose of .2 mL, 1M glutamate is adequate for the activation of normal muscle nociceptors. A larger referred pain area in the latent MTP group than in the normal muscle point group (non-MTP) following the same nociceptive stimulation consolidates the concept that muscle nociceptors at latent MTPs are sensitized (peripheral sensitization) 16 and, in addition, could indicate a subclinical manifestation of central sensitization as larger referred pain areas are seen in, eg, fibromyalgia 15 or whiplash 32 patients with central sensitization.…”

Change the Myofascial Pain and Range of Motion of the Temporomandibular Joint Following Kinesio Taping of Latent Myofascial Trigger Points in the Sternocleidomastoid Muscle

“…Latent trigger points may appear in persons with musculoskeletal pain and may lead to muscle weakness, restricted movement, distorted muscle movement patterns, stiffness and weakness of the affected muscle4 ) . Latent trigger points may develop into active trigger points over time3, 5 ) .…”