High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain Dry Needling on the Infraspinatus Latent and Active Myofascial Trigger Points in Older Adults With Nonspecific Shoulder Pain: A Randomized Clinical Trial Dry Needling to a Key Myofascial Trigger Point May Reduce the Irritability of Satellite MTrPs Dry Needling Alters Trigger Points in the Upper Trapezius Muscle and Reduces Pain in Subjects With Chronic Myofascial Pain. Bilateral Activation of Motor Unit Potentials with Unilateral Needle Stimulation of Active Myofascial Trigger Points Efficacy of Deep Dry Needling on Latent Myofascial Trigger Points in Older Adults With Nonspecific Shoulder Pain: A Randomized, Controlled Clinical Trial Pilot Study Contributions of myofascial pain in diagnosis and treatment of shoulder pain. A randomized control trial An in vivo microanalytical technique for measuring the local biochemical milieu of human skeletal muscle. Upper cervical mobility, posture and myofascial trigger points in subjects with episodic migraine: Case-control study. Active myofascial trigger points might be more frequent in patients with cervical radiculopathy. Induction of muscle cramps by nociceptive stimulation of latent myofascial trigger points Treatment of myofascial trigger-points with ultrasound combined with massage and exercise – a randomised controlled trial Shoulder muscle co-ordination during chronic and acute experimental neck-shoulder pain. An occupational pain study Dry needling of the trapezius muscle in office workers with neck pain: a randomized clinical trial Myofascial Trigger Point-focused Head and Neck Massage for Recurrent Tension-type Headache: A Randomized, Placebo-controlled Clinical Trial Effectiveness of dry needling on the lower trapezius in patients with mechanical neck pain: a randomized controlled trial. Immediate effect of ultrasound and ischemic compression techniques for the treatment of trapezius latent myofascial trigger points in healthy subjects: a randomized controlled study. Effects of compression at myofascial trigger points in patients with acute low back pain: A randomized controlled trial. The Ipswich Microbreak Technique to alleviate neck and shoulder discomfort during microscopic procedures. Changes in masseter muscle trigger points following strain-counterstrain or neuro-muscular technique. Fu's subcutaneous needling: possible clinical evidence of the subcutaneous connective tissue in acupuncture. Follow-up of neck and shoulder pain among sewing machine operators: The Los Angeles garment study. Job task and psychosocial risk factors for work-related musculoskeletal disorders among newspaper employees.
Background Shoulder pain is reported to be highly prevalent and tends to be recurrent or persistent despite medical treatment . The pathophysiological mechanisms of shoulder pain are poorly understood . Furthermore , there is little evidence supporting the effectiveness of current treatment protocol s. Although myofascial trigger points ( MTrPs ) are rarely mentioned in relation to shoulder pain , they may present an alternative underlying mechanism , which would provide new treatment targets through MTrP inactivation . While previous research has demonstrated that trained physiotherapists can reliably identify MTrPs in patients with shoulder pain , the percentage of patients who actually have MTrPs remains unclear . The aim of this observational study was to assess the prevalence of muscles with MTrPs and the association between MTrPs and the severity of pain and functioning in patients with chronic non-traumatic unilateral shoulder pain . Methods An observational study was conducted . Subjects were recruited from patients participating in a controlled trial study ing the effectiveness of physical therapy on patients with unilateral non-traumatic shoulder pain .  Sociodemographic and patient-reported symptom scores , including the Disabilities of the Arm , Shoulder , and H and ( DASH ) Question naire , and Visual Analogue Scales for Pain were compared with other studies . To test for differences in age , gender distribution , and education level between the current study population and the population s from Dutch shoulder studies , the one sample T-test was used . One observer examined all subjects ( n = 72 ) for the presence of MTrPs . Frequency distributions , means , medians , st and ard deviations , and 95 % confidence intervals were calculated for descriptive purpose s. The Spearman 's rank-order correlation ( ρ ) was used to test for association between variables . Results MTrPs were identified in all subjects . The median number of muscles with MTrPs per subject was 6 ( active MTrPs ) and 4 ( latent MTrPs ) . Active MTrPs were most prevalent in the infraspinatus ( 77 % ) and the upper trapezius muscles ( 58 % ) , whereas latent MTrPs were most prevalent in the teres major ( 49 % ) and anterior deltoid muscles ( 38 % ) . The number of muscles with active MTrPs was only moderately correlated with the DASH score . Conclusion The prevalence of muscles containing active and latent MTrPs in a sample of patients with chronic non-traumatic shoulder pain was high 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 Hsieh Y-L , Kao M-J , Kuan T-S , Chen S-M , Chen J-T , Hong C-Z : Dry needling to a key myofascial trigger point may reduce the irritability of satellite myofascial trigger points . Am J Phys Med Rehabil 2007;86:397–403 . Objective : To investigate the changes in pressure pain threshold of the secondary ( satellite ) myofascial trigger points ( MTrPs ) after dry needling of a primary ( key ) active MTrP. Design : Single blinded within-subject design , with the same subjects serving as their own controls ( r and omized ) . Fourteen patients with bilateral shoulder pain and active MTrPs in bilateral infraspinatus muscles were involved . An MTrP in the infraspinatus muscle on a r and omly selected side was dry needled , and the MTrP on the contralateral side was not ( control ) . Shoulder pain intensity , range of motion ( ROM ) of shoulder internal rotation , and pressure pain threshold of the MTrPs in the infraspinatus , anterior deltoid , and extensor carpi radialis longus muscles were measured in both sides before and immediately after dry needling . Results : Both active and passive ROM of shoulder internal rotation , and the pressure pain threshold of MTrPs on the treated side , were significantly increased ( P < 0.01 ) , and the pain intensity of the treated shoulder was significantly reduced ( P < 0.001 ) after dry needling . However , there were no significant changes in all parameters in the control ( untreated ) side . Percent changes in the data after needling were also analyzed . For every parameter , the percent change was significantly higher in the treated side than in the control side . Conclusions : This study provides evidence that dry needle – evoked inactivation of a primary ( key ) MTrP inhibits the activity in satellite MTrPs situated in its zone of pain referral . This supports the concept that activity in a primary MTrP leads to the development of activity in satellite MTrPs and the suggested spinal cord mechanism responsible for this phenomenon 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 Audette JF , Wang F , Smith H : Bilateral activation of motor unit potentialswith  unilateral needle stimulation of active myofascial trigger points . Am J Phys Med Rehabil 2004;83:368–374 . Objective : The objective of this study was to determine if there are electromyographic differences between active and latent myofascial trigger points ( MTrPs ) during trigger point needling . Design : A total of 21 subjects were recruited prospect ively . The experimental group consisted of 13 subjects who had active myofascial pain in the neck for > 6 mos . The age-matched , control group consisted of eight subjects without neck pain but with taut b and s in the cervical musculature . The active MTrPs ( or latent MTrPs in the control group ) were identified in the trapezius or levator scapulae muscles , then needle electrodes were inserted ipsilaterally into the muscle with the MTrPs and into the same muscle on the contralateral side . Electromyographic activity was recorded bilaterally with a dual-channel electromyographic machine , and local twitch responses were obtainedusinganacupuncturedryneedlingtechniqueonlyonthesideoftheactiveMTrPs . Results : We demonstrated that in subjects with active MTrPs , bilateral motor unit activation could be obtained with unilateral needle stimulation of the trigger point . In contrast , in all the subjects with latent MTrPs , only unilateral motor unit activation could be obtained in the muscle on the same side of the needle stimulation . The motor unit potentials seen on the electromyograph were similar in morphology to a fasciculation potential but more complex . Conclusion : We demonstrated bilateral or mirror-image electromyographic activity associated with unilateral needle stimulation of active MTrPs . We have found no previous mention of this phenomenon in the literature . Our study supports the concept that the perpetuation of pain and muscle dysfunction in active MTrPs may be related to abnormal central nervous system processing of sensory input at the level of the spinal cord Background : Nonspecific shoulder pain has a high prevalence in older adults and causes functional alterations . Furthermore , there are difficulties in establishing a clinical diagnosis , effective treatments are lacking , and little evidence has been found regarding the use of invasive physical therapy techniques in this age group . Purpose : To determine the efficacy of a single physical therapy intervention with deep dry needling ( DDN ) on latent and active myofascial trigger points ( MTrPs ) in older adults with nonspecific shoulder pain . Methods : This pilot study is a single-blind , r and omized , controlled clinical trial that included 20 participants , aged 65 years and older , who were diagnosed with nonspecific shoulder pain . The study was approved by the Clinical Research Ethics Committee of the area . Participants were recruited at their homes or at a care center and were r and omly assigned into either an experimental group ( n = 10 ) , which received a session of DDN on 1 active and 1 latent MTrP of the infraspinatus muscle , or a control group ( n = 10 ) , which received a session of DDN on only 1 active MTrP. A blind examiner assessed the pain intensity , pain pressure threshold on the anterior deltoid , and extensor carpi radialis brevis muscles and grip strength before , immediately after , and 1 week after the intervention . Results : Statistically significant differences ( P < .05 ) in the pressure pain thresholds ( PPTs ) of the extensor carpi radialis brevis were found in the experimental group in both posttreatment assessment s. Moreover , the effect size values ( d Cohen ) varied from small for grip strength ( 0.017 - 0.36 ) to moderate for the pain intensity ( 0.46 - 0.78 ) and PPT in the anterior deltoid ( 0.49 - 0.66 ) and to large for the PPT in the extensor carpi radialis brevis ( 1.06 - 1.58 ) . Conclusions : A single physical therapy intervention with DDN on 1 latent MTrP , in conjunction with 1 active MTrP , in the infraspinatus muscle may increase the PPT of the extensor carpi radialis brevis muscle area immediately following and 1 week after the intervention in older adults with nonspecific shoulder pain Background Rotator cuff tendinopathy and subacromial impingement syndrome present complex patomechanical situations , frequent difficulties in clinical diagnosis and lack of effectiveness in treatment . Based on clinical experience , we have therefore considered the existence of another pathological entity as the possible origin of pain and dysfunction . The hypothesis of this study is to relate subacromial impingement syndrome ( SIS ) with myofascial pain syndrome ( MPS ) , since myofascial trigger points ( MTrPs ) cause pain , functional limitation , lack of coordination and alterations in quality of movement , even prior to a tendinopathy . MTrPs can coexist with any degenerative subacromial condition . If they are not taken into consideration , they could perpetuate and aggravate the problem , hindering diagnosis and making the applied treatments ineffective . The aims and methods of this study are related with providing evidence of the relationship that may exist between this condition and MPS in the diagnosis and treatment of rotator cuff tendonitis and /or SIS . Method / design A descriptive transversal study will be made to find the correlation between the diagnosis of SIS and rotator cuff tendonitis , positive provocation test responses , the existence of active MTrPs and the results obtained with ultrasonography ( US ) and Magnetic Renonance Imaging ( MRI ) . A r and omized double blinded clinical trial will be carried out in experimental conditions : A Protocol ized treatment based on active and passive joint repositioning , stabilization exercises , stretching of the periarticular shoulder muscles and postural reeducation . B. The previously described protocol ized treatment , with the addition of dry needling applied to active MTrPs with the purpose of isolating the efficacy of dry needling in treatment . Discussion This study aims to provide a new vision of shoulder pain , from the perspective of MPS . This syndrome can , by itself , account for shoulder pain and dysfunction , although it can coexist with real conditions involving the tendons . Trail Registration IS RCT N Number : 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 OBJECTIVES To evaluate the association between episodic migraines and the prevalence of myofascial trigger points ( MTrPs ) in the sternocleidomastoid and upper trapezius , forward head posture ( FHP ) , neck range of motion ( ROM ) and cervical facet joint stiffness . METHODS 20 physiotherapy students with episodic migraines and 20 age- and sex matched healthy controls were included in this observational case-control study . Demographics and headache status were evaluated through question naires . Active neck ROM , presence of MTrPs , and cervical facet joint mobility were assessed by physical examination . FHP was measured using a lateral digital photograph taken in a sitting position . RESULTS No significant differences were found in neck ROM measurements and FHP between the migraine and control groups . Significant differences were found in the prevalence of cervical facet joints stiffness in Occiput-C1 ( χ(2 ) = 4.444 , p = 0.035 ) and C1-C2 ( χ(2 ) = 10.157 , p = 0.001 ) , but not in other segments . Significant differences were found in the prevalence of active and latent MTrPs between the migraine and control subjects in the right trapezius ( χ(2 ) = 11.649 , p = 0.003 ) and right sternocleidomastoid ( χ(2 ) = 8.485 , p = 0.014 ) . CONCLUSIONS Our findings support the hypothesis that the prevalence of MTrPs in neck muscles and hypomobility in the upper cervical facet joints are associated with migraines BACKGROUND Myofascial trigger points ( MTrPs ) are commonly observed in the neck , parascapular region , and upper back muscles of patients with cervical pathology . AIM To assess the frequency of latent and active myofascial trigger point ( aMTrP ) in the neck and upper back muscles in patients with cervical radiculopathy and healthy subjects . DESIGN Controlled clinical trials . SETTING Out patients and controls . POPULATION Two hundred and forty four patients and 122 controls METHODS The patients clinical ly diagnosed as cervical radiculopathy with positive Spurling 's test and confirmed by MRI , were enrolled in this study . All subjects were examined for active and latent MTrP. In patients with cervical radiculopathy , an aMTrP was distinguished from a latent one when the referred pain elicited by exploration of the MTrP is recognized as familiar . RESULTS The patients comprised of 128 female ( 52.5 % ) and 116 male ( 47.5 % ) patients . Mean age was 44.58(20 - 65 years ) . In 125 ( 51.2 % ) of patients with cervical radiculopathy were found an aMTrP at least one muscle from upper trapezius , multifidus , splenius capitis , levator scapulae , rhomboid major , minor and deep paraspinal muscles . Number and distribution of MTrPs in patients with 244 cervical radiculopathy and in healthy controls .  aMTrPs were detected most common in levator scapula ( 16.3 % ) , splenius capitis ( 14.7 % ) , rhomboid minor ( 14.3 % ) , upper part of trapezius ( 13.5 % ) , rhomboid major ( 10.2 % ) and multifidus ( 8.6 % ) muscles . Patients with cervical radiculopathy showed latent MTrP in levator scapula ( 27 % ) , splenius capitis ( 16.8 % ) , rhomboid minor ( 24.6 % ) , upper part of trapezius ( 33.2 % ) , rhomboid major ( 9 % ) and multifidus ( 8.2 % ) muscles . There was significant difference in terms of distribution of active and latent MTrPs in patients with cervical radiculopathy ( P=0.019 ) . Number of latent MTrPs in upper trapezius muscles in patients with cervical radiculopathy was more than the expected distribution . None of the subjects of control group had aMTrP. However , healthy controls showed latent MTrP in levator scapula ( 33.6 % ) , splenius capitis ( 16.4 % ) , rhomboid minor ( 21.3 % ) , upper part of trapezius ( 40.2 % ) , rhomboid major ( 6.5 % ) and multifidus ( 17.2 % ) muscles . There was no significant difference in terms of distribution of latent MTrPs between cervical radiculopathy and control groups ( P=0.249 ) . The frequency of aMTrP was found to be significantly higher in CDH with median localization as compared to posterolateral herniations ( P=0.041 ) . After conservative treatment for two weeks , number of patients with active MTrP in cervical radiculopathy were decreased about 50 % . CONCLUSION Cervical root compression would be considered as the starting or maintaining factor of aMTrP. CLINICAL REHABILITATION IMPACT The treatment of cervical radiculopathy might be facilitated the improving in aMTrPs located in aforementioned muscles The aim of this present study is to test the hypothesis that nociceptive stimulation of latent myofascial trigger points ( MTrPs ) increases the occurrence of local muscle cramps . Nociceptive muscle stimulation was obtained by a bolus injection of glutamate ( 0.1 ml , 0.5 M ) into a latent MTrP and a control point ( a non-MTrP ) located in the right or left gastrocnemius medialis muscles in 14 healthy subjects . A bolus of isotonic saline ( 0.9 % , 0.1 ml ) injection served as a control . The injections were guided by intramuscular electromyography ( EMG ) showing resting spontaneous electrical activity at a latent MTrP and no such activity at a non-MTrP. Intramuscular and surface EMG activities in the gastrocnemius medialis muscle were recorded pre- , during- , and post-injection for a period of 8 min to monitor the occurrence of muscle cramps , which are characterized by a brief episodic burst of high levels of EMG activity . The results showed that glutamate and isotonic saline injections into the latent MTrPs induced higher peak pain intensity than into the non-MTrPs ( both P < 0.05 ) . Glutamate injection induced higher peak pain intensity than isotonic saline injection into either latent MTrPs or non-MTrPs ( both P < 0.05 ) . Muscle camps were observed in 92.86 % of the subjects following glutamate injection into the latent MTrPs , but not into the non-MTrPs ( P < 0.001 ) . No muscle cramps were recorded following isotonic saline injection into either the latent MTrPs or the non-MTrPs . These results suggest that latent MTrPs could be involved in the genesis of muscle cramps . Focal increase in nociceptive sensitivity at MTrPs constitutes one of the mechanisms underlying muscle cramps & NA ; The effect of treatment with ultrasound , massage and exercises on myofascial trigger‐points ( MTrP ) in the neck and shoulder was assessed in a r and omised controlled trial . The outcome measures were pain at rest and on daily function ( Visual Analogue Scale , VAS ) , analgesic usage , global preference and index of MTrP. Long‐term effect for treatment and control groups was assessed after 6 months using a question naire . The patients were r and omised to three groups . The first group was treated with ultrasound , massage and exercise ( A ) , the second group with sham‐ultrasound , massage and exercise ( B ) , while the third group was a control group ( C ) . The duration of the study was 6 weeks . Treatment was given twice a week from the second to the fifth week . The number and index of MTrPs were recorded at each treatment session in groups A and B but only at entry as well as end of study in group C. VAS and analgesic usage was recorded in all three groups throughout the study period . Six months after the last treatment session a question naire was send to the patients . A total of 67 patients were included . Nine patients dropped‐out during the study , which left 58 patients that could be included in the final analysis . Twenty patients were r and omised to group A , 18 to group B and 18 to group C. A significant reduction in index were found between treatment groups ( A and B ) and control group ( C ) , but no difference between group A and B. VAS scores , analgesic usage or global preference showed no difference between group A , B or C. The patients in the group C were offered treatment ( ultrasound , massage , exercise ) after the 6 weeks treatment period . At the question naire after 6 month 44 ( 87 % ) of the 52 patients from all three groups who had treatment responded . Sixty‐four percent answered that they had had good or some effects , 68 percent were still doing the exercise programme and 17 percent had received other forms of therapy after they had completed the study . No difference between groups given ultrasound or sham ultrasound were found . It is concluded that US give no pain reduction , but apparently massage and exercise reduces the number and intensity of MTrP. The impact of this reduction on neck and shoulder pain is weak Abstract Little is known about the mechanisms leading to chronic neck-shoulder musculoskeletal disorders  ( MSD ) . The aim of the present study was to investigate and compare motor function during controlled , low load , repetitive work together with chronic or acute experimental neck-shoulder pain . The clinical study was performed on workers with ( n = 12 ) and without ( n = 6 ) chronic neck-shoulder pain . In the experimental study , experimental muscle pain was induced in healthy subjects by intra-muscular injection of hypertonic saline into the trapezius muscle ( n = 10 ) . The assessed parameters related to motor performance were : work task event duration , cutting forces , surface electromyogram ( EMG ) activity in four shoulder muscles , displacement of the centre of pressure , and arm and trunk 3D movements . For controlled cutting force levels , chronic and acute experimental pain provoked a series of changes : a decreased working rhythm and a protective reorganisation of muscle synergy ( experimental study ) , higher EMG frequency contents which may indicate altered motor unit recruitment , and greater postural activity and a tendency towards increased arm and trunk movements . These pain-related changes can play a role in the development of MSD . The present clinical and experimental study demonstrated similar interactions between motor co-ordination and neck-shoulder pain in occupational setting s. We therefore suggest that this experimental model can be used to study mechanisms related to MSD . Information on such modulatory processes may help in the design of new strategies aim ed at reducing the development of MSD Background : Neck pain is a frequent complaint in office workers . This pain can be caused by myofascial trigger points ( MTrPs ) in the trapezius muscle . This study aim ed to determine the effectiveness of deep dry needling ( DDN ) of active MTrPs in the trapezius muscle . Methods : A r and omized , single blinded clinical trial was carried out at the Physical Therapy Department at Physiotherapy in Women 's Health Research Group at Physical Therapy Department of University of Alcalá , in Alcalá de Henares , Madrid , Spain . Forty-four office workers with neck pain and active MTrPs in the trapezius muscle were r and omly allocated to either the DDN or the control group ( CG ) . The participants in the DDN group were treated with DDN of all MTrPs found in the trapezius muscle . They also received passive stretch of the trapezius muscle . The CG received the same passive stretch of the trapezius muscle only . The primary outcome measure was subjective pain intensity , measured using a visual analogue scale ( VAS ) . Secondary outcomes were pressure pain threshold ( PPT ) , cervical range of motion ( CROM ) and muscle strength . Data were collected at baseline , after interventions and 15 days after the last treatment . Results : Differences were found between the DDN group and the CG for the VAS ( P < 0.001 ) , PPT ( P < 0.001 ) , range of motion ( AROM ) ( P < 0.05 ) and strength ( P < 0.05 ) after intervention and at the 15-day follow-up . Discussion : Deep dry needling and passive stretch seems to be more effective than passive stretch only . The effects are maintained in the short term . The results support the use of DDN in the management of trapezius muscle myofascial pain syndrome in neck pain Objective : Myofascial trigger points ( MTrPs ) are focal disruptions in the skeletal muscle that can refer pain to the head and reproduce the pain patterns of tension-type HA ( TTH ) . The present study applied massage focused on MTrPs of patients with TTH in a placebo-controlled , clinical trial to assess efficacy on reducing headache ( HA ) pain . Methods : Fifty-six patients with TTH were r and omized to receive 12 massage or placebo ( detuned ultrasound ) sessions over 6 weeks , or to wait-list . Trigger point release massage focused on MTrPs in cervical musculature . HA pain ( frequency , intensity , and duration ) was recorded in a daily HA diary . Additional outcome measures included self-report of perceived clinical change in HA pain and pressure-pain threshold at MTrPs in the upper trapezius and suboccipital muscles . Results : From diary recordings , group differences across time were detected in HA frequency ( P=0.026 ) , but not for intensity or duration . Post hoc analysis indicated that HA frequency decreased from baseline for both massage ( P<0.0003 ) and placebo ( P=0.013 ) , but no difference was detected between massage and placebo . Patient report of perceived clinical change was greater reduction in HA pain for massage than placebo or wait-list groups ( P=0.002 ) . Pressure-pain threshold improved in all muscles tested for massage only ( all P’s<0.002 ) . Discussion : Two findings from this study are apparent : ( 1 ) MTrPs are important components in the treatment of TTH , and ( 2 ) TTH , like other chronic conditions , is responsive to placebo . Clinical trials on HA that do not include a placebo group are at risk for overestimating the specific contribution from the active intervention OBJECTIVE To evaluate the effect of dry needling into a myofascial trigger point ( MTrP ) in the lower trapezius muscle of patients with mechanical idiopathic neck pain . DESIGN A single-center , r and omized , double-blinded controlled study . SETTING Patients were recruited from the student population of a local hospital by advertisement in the university clinic from January 2010 to December 2011 . PARTICIPANTS Patients ( N=72 ) with unilateral neck pain , neck pain for ≥3 months , and active trigger points in the lower trapezius muscle were r and omly assigned to 1 of 2 treatment groups . All the patients completed the study . INTERVENTIONS Dry needling in an MTrP in the lower trapezius muscle , or dry needling in the lower trapezius muscle but not at an MTrP. MAIN OUTCOME MEASURES The visual analog scale ( VAS ) , Neck Pain Question naire ( NPQ ) , and pressure-pain threshold ( PPT ) were assessed before the intervention and 1 week and 1 month postintervention . RESULTS Treatment with dry needling of the lower trapezius muscle close to the MTrP showed decreases in pain and PPT as well as an improvement in the degree of disability ( P<.001 ) compared with the baseline and control group measurements ( P<.001 ) . The dry-needling technique performed in the MTrP showed more significant therapeutic effects ( P<.001 ) . CONCLUSIONS The application of dry needling into an active MTrP of the lower trapezius muscle induces significant changes in the VAS , NPQ , and PPT levels compared with the application of dry needling in other locations of the same muscle in patients with mechanical neck pain OBJECTIVE The purpose of this study was to determine immediate effects of ischemic compression ( IC ) and ultrasound ( US ) for the treatment of myofascial trigger points ( MTrPs ) in the trapezius muscle . METHODS Sixty-six volunteers , all CEU-Cardenal Herrera University , Valencia , Spain , personnel , participated in this study . Subjects were healthy individuals , diagnosed with latent MTrPs in the trapezius muscle . Subjects were r and omly placed into 3 groups : G1 , which received IC treatment for MTrPs ; G2 , which received US ; and G3 ( control ) , which received sham US . The following data were recorded before and after each treatment : active range of motion ( AROM ) of cervical rachis measured with a cervical range of motion instrument , basal electrical activity ( BEA ) of muscle trapezius measured with surface electromyography , and pressure tolerance of MTrP measured with visual analogue scale assessing local pain evoked by the application of 2.5 kg/cm(2 ) of pressure using a pressure analog algometer . RESULTS The results showed an immediate decrease in BEA of the trapezius muscle and a reduction of MTrP sensitivity after treatment with both therapeutic modalities . In the case of IC , an improvement of AROM of cervical rachis was also been obtained . CONCLUSION In this group of participants , both treatments were shown to have an immediate effect on latent MTrPs . The results show a relation among AROM of cervical rachis , BEA of the trapezius muscle , and MTrP sensitivity of the trapezius muscle gaining short-term positive effects with use of IC BACKGROUND Although there is some evidence that massage therapy , especially compression at myofascial trigger points ( MTrPs ) , is effective for sub-acute and chronic low back pain , the effectiveness of massage therapy with compression at MTrPs for acute low back pain has not been studied . METHODS To evaluate the effectiveness of compression at MTrPs for acute low back pain , 63 patients with acute low back pain were r and omly assigned to one of three groups : the MTrP group who received compression at MTrPs ( N = 23 ) , the non-MTrP group who received compression at non-trigger points ( N = 21 ) , and the effleurage massage group who received superficial massage ( N = 19 ) . The patients received the assigned treatment 3 times/week for 2 weeks . The subjective pain intensity in static and dynamic conditions and disability caused by low back pain were measured by the visual analogue scale ( VAS ) and Rol and -Morris question naire ( RMQ ) , respectively ; along with the range of motion ( ROM ) at the lumbar region and pressure pain threshold ( PPT ) at trigger points before treatment ( baseline ) , 1 week after the start of treatment , and 1 month after the end of treatment ( follow-up ) . RESULTS Static and dynamic VAS score , PPT and ROM were significantly improved in the MTrP group compared with those in the non-MTrP and effleurage groups . CONCLUSIONS These results indicate that compression at MTrPs is effective to treat acute low back pain compared with compression at non-MTrPs and superficial massage . For this article , a commentary is available at the Wiley Online Library Neck and shoulder disorders are a considerable health problem amongst frequent microscope users . We aim ed to investigate the neck and shoulder discomfort experienced during prolonged microscopic activity and to assess the benefits of minibreaks . A prospect i ve crossover study was performed on 17 healthy volunteers sitting still while looking down a bench with and without the Ipswich Microbreak Technique ( IMT ) .  We used a subjective measure of time to fatigue and pain in the neck and shoulder regions as well as objective readings from a surface electromyogram ( sEMG ) . The IMT delayed the sensation of pain in the neck and shoulder region while reducing the overall sEMG muscle activation . In conclusion , IMT is a useful strategy in reducing and delaying the pain in neck and shoulder from prolonged working under the microscope . This technique can be incorporated in other activities that involve a sustained stationary position The aim of this study was to compare the immediate effects , on pressure pain sensitivity and active mouth opening , following the application of neuromuscular or strain/counter-strain technique in latent myofascial trigger points ( MTrPs ) in the masseter muscle . Seventy-one subjects , 34 men and 37 women , aged 20 - 65 years old , participated in this study . Subjects underwent a screening process to establish the presence of MTrPs in the masseter muscle . Subjects were divided r and omly into three groups : group A which was treated with a neuromuscular intervention , group B treated with the strain/counter-strain technique , and group C as control group . Each treatment group received a weekly treatment session during 3 consecutive weeks . Outcomes measures were pressure pain thresholds ( PPTs ) , active mouth opening and local pain ( visual analogue scale , VAS ) elicited by the application of 2.5kg/cm(2 ) of pressure over the MTrP. They were captured at baseline and 1 week after discharge by an assessor blinded to the treatment allocation of the subject . The ANOVA found a significant groupxtime interaction ( F=25.3 ; p<0.001 ) for changes in PPT , changes in active mouth opening ( F=10.5 ; p<0.001 ) , and local pain evoked by 2.5kg/cm(2 ) of pressure ( F=10.1 ; p<0.001 ) . Within-group effect sizes were large ( d>1 ) for PPT and mouth opening , and moderate for local pain ( d<0.7 , 0.5 ) in both intervention groups ; but small ( d<0.2 ) for the control group in all outcomes . No significant differences between both intervention groups were found for any outcome ( p>0.8 ) . Our results suggest that neuromuscular or strain/counter-strain technique might be employed in the management of latent MTrPs in the masseter muscle OBJECTIVES Recently it was reported that the loose connective tissue in the subcutaneous layer rapidly responded to mechanical forces evoked by acupuncture , massage , and normal physical movements . However , there were no clinical studies to substantiate these findings so far . Fu 's Subcutaneous Needling ( FSN ) is the innovative needling strategy acting specifically in the subcutaneous layer . A single-blinded and r and omized trial was design ed to compare the immediate effects of FSN with different needling directions on myofascial trigger points ( MTrP ) in the neck . DESIGN For simplicity , we chose two mutually perpendicular needle directions in this study . In one group , the needle was along the local muscle fibers and pointed to the MTrP ( Along Group ) . In the other group , the needle was across the local muscle fibers and also pointed to the MTrP ( Across Group ) . SUBJECTS Forty-seven ( 47 ) patients were r and omly divided into two groups : the Along Group ( n = 22 ) and the Across Group ( n = 25 ) . There were no significant differences with respect to age , duration of pain , and gender between the two groups . INTERVENTIONS FSN needles were inserted and swayed in the subcutaneous layer 200 times in 2 minutes . RESULTS Before and after FSN treatment , patients were subjected to the assessment of the following three parameters : motion-related pain , pain under pressure , and the range of cervical movement . Three parameters were all reduced after the FSN intervention . There were no significant differences in variation of the three parameters between the two groups . CONCLUSION Immediate effects of FSN on alleviating MTrP in the neck were not relevant to the needling directions BACKGROUND The aim of the present study is to explore factors affecting or modifying self-reported neck/shoulder pain in sewing machine operators . METHODS We investigated self-report neck/shoulder pain in 247 workers who participated in a 4-month prospect i ve intervention study for musculoskeletal disorders . All participants were immigrants . We examine the influence of individual and work-related factors on changes in neck/shoulder pain during follow-up employing linear mixed models with time-spline functions . RESULTS We observed a dramatic decline ( 72 % ) in self-reported pain intensity in the first month of follow-up , followed by a small increase from the first to fourth month ( 4 % per month ) . Workers who perceived and reported their physical workload as high or worked overtime experienced less overall pain reduction . Higher baseline pain intensity , being of Hispanic ethnicity ( vs. Asian ) , and taking cumulative daily rest time during work of 35 min or more allowing for muscles to rest were associated with a larger pain reduction in the first month , but not thereafter . CONCLUSION Our findings indicate that some work-related factors may be of clinical relevance for reducing neck/shoulder pain . Having lower physical workloads and less overtime work should be considered when treating patients or planning workplace interventions for managing work-related musculoskeletal disorders in this underserved immigrant population OBJECTIVES A cross-sectional study was conducted to assess the association of upper extremity musculoskeletal disorders and work-related factors among employees using video display terminals at a large metropolitan newspaper . METHODS The study included 1050 r and omly selected workers from four departments . The workers were asked to complete question naires on symptoms , job tasks , and psychosocial and work organization conditions . Musculoskeletal disorders of the upper extremities were defined by frequency , duration , and intensity of symptoms not attributable to acute injury . Data were analyzed with the use of logistic regression . RESULTS A total of 973 workers completed the survey . The one-year period prevalence rate for any musculoskeletal disorder of the upper extremities was 41 % . Neck symptoms ( 26 % ) were the most frequently reported , followed by h and or wrist ( 22 % ) , shoulder ( 17 % ) , and elbow ( 10 % ) symptoms . Greater time working at the video display station was associated with increased h and or wrist symptoms in a dose-response relationship . In addition , variables corresponding to increased work-load dem and s ( eg , increased time working under deadline and increased job pressure ) were associated with increased neck , shoulder , and h and or wrist disorders . Women were more likely to report symptoms in several areas , but this finding may reflect the concentration of women in jobs involving more risk factors . CONCLUSIONS The results suggest a high prevalence of musculoskeletal disorders of the upper extremities among newspaper employees , and they provide additional evidence that increased work load , time pressure , and greater hours of computer use are related to the occurrence of work-related musculoskeletal disorders among these workers , particularly for disorders in the h and or wrist area
Findings revealed that active and latent MTrPs were prevalent throughout all disorders , however , latent MTrPs did not consistently have a higher prevalence compared to healthy controls .
Conclusions We found limited evidence supporting the high prevalence of active and latent MTrPs in patients with neck or shoulder disorders .
Background Neck and shoulder disorders may be linked to the presence of myofascial trigger points ( MTrPs ) .
These disorders can significantly impact a person ’s activities of daily living and ability to work .
MTrPs can be involved with pain sensitization , contributing to acute or chronic neck and shoulder musculoskeletal disorders .
The aim of this review was to synthesis e evidence on the prevalence of active and latent MTrPs in subjects with neck and shoulder disorders .