Within spinal pain , patients with neck pain were found to have the highest prevalence rates of MTrPs .
The trapezius descendens , levator scapulae , and suboccipitales muscles were the most prevalent locations for active MTrPs in patients with neck pain .
Latent MTrPs were present in asymptomatic people , but no significant differences were found in the prevalence rate of latent MTrPs between patients with spinal ( neck ) pain and healthy controls .
The only study investigating prevalence of MTrPs in different localizations of the same muscle reported no significant differences in prevalence between active and latent MTrPs within the trapezius descendens muscle .
Studies examining pathophysiological mechanisms underlying MTrPs demonstrated an acidic environment , high concentration of algogenic/inflammatory substances , stiffer muscle tissue , retro grade diastolic blood flows , spontaneous muscle activity at rest , and loss of muscle contractibility in muscles with MTrPs .
Altered central processing was also found to play a role in the development of MTrPs .
Myofascial trigger points are a prevalent clinical entity , especially in patients with neck pain .
Evidence was not found to support or deny the role of MTrPs in other spinal pain .
Compelling evidence supports local mechanisms underlying MTrPs .
OBJECTIVE A systematic review was performed to evaluate the existing evidence related to the prevalence , incidence , localization , and pathophysiology of myofascial trigger points ( MTrPs ) in patients with spinal ( back and neck ) pain .
Dry needle stimulation of myofascial trigger points evokes segmental anti-nociceptive effects.
OBJECTIVE To test the hypothesis that dry needle stimulation of a myofascial trigger point ( sensitive locus ) evokes segmental anti-nociceptive effects . DESIGN Double-blind r and omized controlled trial . SUBJECTS Forty subjects ( 21 males , 19 females ) . METHODS Test subjects received intramuscular dry needle puncture to a right supraspinatus trigger point ( C4,5 ) ; controls received sham intramuscular dry needle puncture .  Pain pressure threshold ( PPT ) readings were recorded from right infraspinatus ( C5,6 ) and right gluteus medius ( L4,5S1 ) trigger points at 0 ( pre-needling baseline ) , 1 , 3 , 5 , 10 and 15 min post-needling and normalized to baseline values . The supraspinatus and infraspinatus trigger points are neurologically linked at C5 ; the supraspinatus and gluteus medius are segmentally unrelated . The difference between the infraspinatus and gluteus medius PPT values ( PPTseg ) represents a direct measure of the segmental anti-nociceptive effects acting at the infraspinatus trigger point . RESULTS Significant increases in PPTseg were observed in test subjects at 3 ( p = 0.002 ) and 5 ( p = 0.015 ) min post-needling , compared with controls . CONCLUSION One intervention of dry needle stimulation to a single trigger point ( sensitive locus ) evokes short-term segmental anti-nociceptive effects . These results suggest that trigger point ( sensitive locus ) stimulation may evoke anti-nociceptive effects by modulating segmental mechanisms , which may be an important consideration in the management of myofascial pain
Within spinal pain , patients with neck pain were found to have the highest prevalence rates of MTrPs .
The trapezius descendens , levator scapulae , and suboccipitales muscles were the most prevalent locations for active MTrPs in patients with neck pain .
Latent MTrPs were present in asymptomatic people , but no significant differences were found in the prevalence rate of latent MTrPs between patients with spinal ( neck ) pain and healthy controls .
The only study investigating prevalence of MTrPs in different localizations of the same muscle reported no significant differences in prevalence between active and latent MTrPs within the trapezius descendens muscle .
Studies examining pathophysiological mechanisms underlying MTrPs demonstrated an acidic environment , high concentration of algogenic/inflammatory substances , stiffer muscle tissue , retro grade diastolic blood flows , spontaneous muscle activity at rest , and loss of muscle contractibility in muscles with MTrPs .
Altered central processing was also found to play a role in the development of MTrPs .
Myofascial trigger points are a prevalent clinical entity , especially in patients with neck pain .
Evidence was not found to support or deny the role of MTrPs in other spinal pain .
Compelling evidence supports local mechanisms underlying MTrPs .
OBJECTIVE A systematic review was performed to evaluate the existing evidence related to the prevalence , incidence , localization , and pathophysiology of myofascial trigger points ( MTrPs ) in patients with spinal ( back and neck ) pain .