***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVES To compare the efficacies of dry needling of trigger points ( TrPs ) with and without paraspinal needling in myofascial pain syndrome of elderly patients . DESIGN Single-blinded , r and omized controlled trial . SUBJECTS Forty ( 40 ) subjects , between the ages of 63 and 90 with myofascial pain syndrome of the upper trapezius muscle . INTERVENTIONS Eighteen ( 18 ) subjects were treated with dry needling of all the TrPs only and another 22 with additional paraspinal needling on days 0 , 7 , and 14 . RESULTS At 4-week follow-up the results were as follows : ( 1 ) TrP and paraspinal dry needling result ed in more continuous subjective pain reduction than TrP dry needling only ; ( 2 ) TrP and paraspinal dry needling result ed in significant improvements on the geriatric depression scale but TrP dry needling only did not ; ( 3 ) TrP and paraspinal dry needling result ed in improvements of all the cervical range of motions but TrP dry needling  only did not in extensional cervical range of motion ; and ( 4 ) no cases of gross hemorrhage were noted . CONCLUSIONS TrP and paraspinal dry needling is suggested to be a better method than TrP dry needling only for treating myofascial pain syndrome in elderly patients Myofascial pain associated with myofascial trigger points ( MTrPs ) is a common cause of nonarticular musculoskeletal pain . Although the presence of MTrPs can be determined by soft tissue palpation , little is known about the mechanisms and biochemical milieu associated with persistent muscle pain . A microanalytical system was developed to measure the in vivo biochemical milieu of muscle in near real time at the subnanogram level of concentration . The system includes a microdialysis needle capable of continuously collecting extremely small sample s ( approximately 0.5 microl ) of physiological saline after exposure to the internal tissue milieu across a 105-microm-thick semi-permeable membrane . This membrane is positioned 200 microm from the tip of the needle and permits solutes of < 75 kDa to diffuse across it . Three subjects were selected from each of three groups ( total 9 subjects ) : normal ( no neck pain , no MTrP ) ; latent ( no neck pain , MTrP present ) ; active ( neck pain , MTrP present ) . The microdialysis needle was inserted in a st and ardized location in the upper trapezius muscle . Due to the extremely small sample size collected by the microdialysis system , an established microanalytical laboratory , employing immunoaffinity capillary electrophoresis and capillary electrochromatography , performed analysis of selected analytes . Concentrations of protons , bradykinin , calcitonin gene-related peptide , substance P , tumor necrosis factor-alpha , interleukin-1beta , serotonin , and norepinephrine were found to be significantly higher in the active group than either of the other two groups ( P < 0.01 ) . pH was significantly lower in the active group than the other two groups ( P < 0.03 ) . In conclusion , the described microanalytical technique enables continuous sampling of extremely small quantities of substances directly from soft tissue , with minimal system perturbation and without harmful effects on subjects . The measured levels of analytes can be used to distinguish clinical ly distinct groups Objective To assess the efficacy of trigger point injection into brachialis muscle for rotator cuff disease patients with upper arm pain . Methods A prospect i ve , r and omized , and single-blinded clinical pilot trial was performed at university rehabilitation hospital . Twenty-one patients clinical ly diagnosed with rotator cuff disease suspected of having brachialis myofascial pain syndrome ( MPS ) were r and omly allocated into two groups . Effect of ultrasound (US)-guided trigger point injection ( n=11 ) and oral non-steroidal anti-inflammatory drug ( NSAID ) ( n=10 ) was compared by visual analog scale ( VAS ) . Results US-guided trigger point injection of brachialis muscle result ed in excellent outcome compared to the oral NSAID group . Mean VAS scores decreased significantly after 2 weeks of treatment compared to the baseline in both groups ( 7.3 vs. 4.5 in the injection group and 7.4 vs. 5.9 in the oral group ) . The decrease of the VAS score caused by injection ( ДVAS=-2.8 ) was significantly larger than caused by oral NSAID ( ДVAS=-1.5 ) ( p<0.05 ) . Conclusion In patients with rotator cuff disease , US-guided trigger point injection of the brachialis muscle is safe and effective for both diagnosis and treatment when the cause of pain is suspected to be originated from the muscle Background and Purpose : Shoulder pain is a prevalent condition in older adults . Some authors associate nonspecific shoulder pain with myofascial trigger points ( MTrPs ) in the infraspinatus muscle . Dry needling is recommended to relieve the MTrP pain of shoulders in the short term ( < 9 days ) . Active MTrPs dry needling improves shoulder pain and the irritability of the satellite MTrPs in the referred pain area . Nociceptive activity at a latent MTrP may influence motor activity and the sensitivity of MTrPs in distant muscles at a similar segmental level . Therefore , this study aim ed to evaluate dry needling on 1 latent MTrP , in conjunction with 1 active MTrP , in the infraspinatus muscle of older adults with nonspecific shoulder pain . Methods : A single-center , r and omized , single-blinded , controlled study ( NCT02032602 ) was carried out . Sixty-six patients aged 65 years and older with trigger points in the ipsilateral infraspinatus of the painful shoulder were r and omly assigned to ( 1 ) of ( 2 ) treatment groups . A session of dry needling on the infraspinatus was performed in ( 1 ) the most hyperalgesic active and latent MTrP or ( 2 ) only the most hyperalgesic active MTrP. The Numeric Rating Scale , the pressure pain threshold ( primary outcome ) on the anterior deltoid and extensor carpi radialis brevis latent MTrPs , and grip strength were assessed before , after , and 1 week after the intervention . Results : Statistically significant differences in the reduction of pain intensity ( P ⩽ .001 ; & eegr;2 = 0.159 - 0.269 ; d = 1.017 - 1.219 ) and the increase of pressure pain threshold ( P < .001 ; & eegr;2 = 0.206 - 0.481 ; d = 0.870 - 1.924 ) were found for the ( 1 ) treatment group immediately and 1 week postintervention . Nevertheless , no statistical significant differences were found in grip strength ( P > . 05 ; & eegr;2 = 0.006 - 0.033 ; d = 0.158 - 0.368 ) . Conclusions : One dry needling intervention of the latent MTrP associated with the key active MTrP of the infraspinatus reduces pain intensity and the irritability of the satellite MTrPs located in the referred pain area in the short term in older adults with nonspecific shoulder pain BACKGROUND Trigger points , which have been defined as highly localized , hyperirritable locations in a palpable taut b and of skeletal muscle fibers , have been identified with a variety of musculoskeletal conditions . The incidence of trigger point pain is high , with studies showing them as the primary source of pain in 30 - 85 % of patients presenting in a primary care setting or pain clinic .  Dry needling has emerged as a possible intervention for trigger points , but its effectiveness has not yet fully been determined . PURPOSE To assess and provide a summary on the current literature for the use of dry needling as an intervention for lower quarter trigger points in patients with various orthopedic conditions . STUDY DESIGN Systematic review . METHODS CINAHL , NCBI- PubMed , PEDro , SPORTD iscus , Cochrane Library , and APTA 's PTNow were search ed to identify relevant r and omized controlled trials . Six studies meeting the inclusion criteria were analyzed using the PEDro scale . RESULTS Four of the studies assessed by the PEDro scale were deemed ' high ' quality and two were ' fair ' quality . Each of the six included studies reported statistically significant improvements with  dry needling  for the reduction of pain intensity in the short-term . Only one study reported a statistically significant improvement in short-term functional outcomes ; however , there was no maintenance of improved function at long-term follow-up . Furthermore , none of the studies reported statistically significant changes regarding the effect of dry needling on quality of life , depression , range of motion , or strength . CONCLUSION A review of current literature suggests that dry needling is effective in reducing pain associated with lower quarter trigger points in the short-term . However , the findings suggest that dry needling does not have a positive effect on function , quality of life , depression , range of motion , or strength . Further high quality research with long-term follow-up investigating the effect of dry needling in comparison to and in conjunction with other interventions is needed to determine the optimal use of dry needling in treating patients with lower quarter trigger points . LEVELS OF EVIDENCE 1 OBJECTIVE To investigate the relationship between dry needling-induced twitch response and change in pain , disability , nociceptive sensitivity , and lumbar multifidus muscle function , in patients with low back pain ( LBP ) . DESIGN Quasi-experimental study . SETTING Department of Defense Academic Institution . PARTICIPANTS Sixty-six patients with mechanical LBP ( 38 men , 28 women , age : 41.3 [ 9.2 ] years ) . INTERVENTIONS Dry needling treatment to the lumbar multifidus muscles between L3 and L5 bilaterally . MAIN OUTCOME MEASURES Examination procedures included numeric pain rating , the Modified Oswestry Disability Index , pressure algometry , and real-time ultrasound imaging assessment of lumbar multifidus muscle function before and after dry needling treatment . Pain pressure threshold ( PPT ) was used to measure nocioceptive sensitivity . The percent change in muscle thickness from rest to contraction was calculated to represent muscle function . Participants were dichotomized and compared based on whether or not they experienced at least one twitch response on the most painful side and spinal level during dry needling . RESULTS Participants experiencing local twitch response during dry needling exhibited greater immediate improvement in lumbar multifidus muscle function than participants who did not experience a twitch ( thickness change with twitch : 12.4 [6]% , thickness change without twitch : 5.7 [11]% , mean difference adjusted for baseline value , 95%CI : 4.4 [ 1 to 8]% ) . However , this difference was not present after 1-week , and there were no between-groups differences in disability , pain intensity , or nociceptive sensitivity . CONCLUSIONS The twitch response during dry needling might be clinical ly relevant , but should not be considered necessary for successful treatment OBJECTIVE To determine whether dry needling of an active myofascial trigger point ( MTrP ) reduces pain and alters the status of the trigger point to either a non-spontaneously tender nodule or its resolution . DESIGN A prospect i ve , nonr and omized , controlled , interventional clinical study . SETTING University campus . PARTICIPANTS A total of 56 subjects with neck or shoulder girdle pain of more than 3 months duration and active MTrPs were recruited from a campus-wide volunteer sample . Of these , 52 completed the study ( 23 male and 33 female ) . Their mean age was 35.8 years . INTERVENTIONS Three weekly dry needling treatments of a single active MTrP. MAIN OUTCOME MEASURES PRIMARY OUTCOMES Baseline and posttreatment evaluations of pain using a verbal analogue scale , the Brief Pain Inventory , and the status of the MTrP as determined by digital palpation . Trigger points were rated as active ( spontaneously painful ) , latent ( requiring palpation to reproduce the characteristic pain ) , or resolved ( no palpable nodule ) . SECONDARY OUTCOMES Profile of Mood States , Oswestry Disability Index , and Short Form 36 scores , and cervical range of motion . RESULTS PRIMARY OUTCOMES A total of 41 subjects had a change in trigger point status from active to latent or resolved , and 11 subjects had no change ( P < .001 ) . Reduction in all pain scores was significant ( P < .001 ) . SECONDARY OUTCOMES Significant improvement in posttreatment cervical rotational asymmetry in subjects as follows : unilateral/bilateral MTrPs ( P = .001 and P = 21 , respectively ) ; in pain pressure threshold in subjects with unilateral/bilateral MTrPs , ( P = .006 and P = .012 , respectively ) ; improvement in the SF-36 mental health and physical functioning subscale scores ( P = .019 and P = .03 ) , respectively ; and a decrease in the Oswestry Disability Index score ( P = .003 ) . CONCLUSIONS Dry needling reduces pain and changes MTrP status . Change in trigger point status is associated with a statistically and clinical ly significant reduction in pain . Reduction of pain is associated with improved mood , function , and level of disability 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 punct 
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RESULTS and Discussion : Several studies show that eliciting a LTR does not correlate with changes in pain and disability , and multiple systematic review s have failed to conclude whether the LTR is relevant to the outcome of TrPDN .
Post needling soreness is consistently reported in studies using repeated in and out needling to elicit LTRs and increases in proportion to the number of needle insertions .
In contrast , needle winding without LTRs to MTrPs and connective tissue is well supported in the literature , as it is linked to anti-nociception and factors related to tissue repair and remodeling .
Additionally , the positive biochemical changes in the MTrP after needling may simply be a wash out effect related to local vasodilation .