Bilateral Activation of Motor Unit Potentials with Unilateral Needle Stimulation of Active Myofascial Trigger Points

Functional connectivity patterns are altered by low back pain and cause different responses to sham and real dry needling therapies: a systematic review of fMRI studies

BACKGROUND

There is a relationship between low back pain (LBP) and central nervous system dysfunction. Needling therapies (e.g. acupuncture, dry needling) are proposed to impact the nervous system, however their specific influence is unclear.

PURPOSE

Determine how needling therapies alter functional connectivity and LBP as measured by functional magnetic resonance imaging (fMRI).

METHODS

Databases were searched following PRISMA guidelines. Studies using fMRI on individuals with LBP receiving dry needling or acupuncture compared to control or sham treatments were included.

RESULTS

Eight studies were included, all of which used acupuncture. The quality of studies ranged from good (n = 6) to excellent (n = 2). After acupuncture, individuals with LBP demonstrated significant functional connectivity changes across several networks, notably the salience, somatomotor, default mode network (DMN) and limbic networks. A meta-analysis demonstrated evidence of no effect to potential small effect of acupuncture in reducing LBP (SMD -0.28; 95% CI: -0.70, 0.13).

CONCLUSION

Needling therapies, like acupuncture, may have a central effect on patients beyond the local tissue effects, reducing patients' pain and disability due to alterations in neural processing, including the DMN, and potentially other central nervous system effects. The meta-analysis should be interpreted with caution due to the narrow focus and confined sample used.

Effectiveness of different percutaneous electrolysis protocols in the endogenous modulation of pain: A Double-Blinded Randomized Clinical Trial

OBJECTIVE

This randomized clinical trial investigated if the application of percutaneous electrolysis (PE) enhances endogenous pain mechanisms (EPM) when compared with a simple needle application (acting as sham).

METHODS

Forty-six asymptomatic subjects, aged 18-40 years, were randomized into three groups receiving a single ultrasound-guided PE intervention consisting of a needle insertion on the lateral epicondyle: sham (without electrical current), low-intensity (0.3 mA, 90s), or high-intensity (three pulses of 3 mA, 3s) PE. Widespread pressure pain thresholds (PPT), conditioned pain modulation (CPM), and temporal summation (TS) were bilaterally assessed in the lateral epicondyle, bicipital groove, transverse process of C5 and tibialis anterior muscle. Outcomes were obtained by an assessor blinded to the treatment allocation of the subjects.

RESULTS

No significant changes in CPM were observed in either group (omnibus ANOVA all, P > .05). A significant bilateral increase in PPT in the lateral epicondyle in the high intensity group as compared with the sham group was observed (P < .01). A significant decrease of TS in both low (P = .002) and high (P = .049) intensity groups on the right, but not on the left, tibialis anterior was also observed when compared with the sham group.

CONCLUSIONS

One session of PE is able to slightly stimulate modulatory pathways related to nociceptive gain, particularly pressure pain sensitivity and temporal summation but not conditioning pain modulation, when compared with a sham needle intervention, with changes even contralaterally. No significant differences were found between low- and high-intensity doses of percutaneous electrolysis.

Recovery of two elite footballers from adductor strain with dry needling and eccentric strengthening: Two case studies

INTRODUCTION

Groin injuries are common in sports, almost 68% adductor strain among them, which generally more prone in football, soccer, hockey, and other games. The available literature well describes the rehabilitation phase of adductor strain but an application of dry needling on adductor injuries are not yet established.

CASE DESCRIPTION

Two national-level younger football players were clinically diagnosed with the adductor strain. They had severe pain on medial aspect of the thigh, aggravated with kicking and functional activity (VAS- 8/10, LEFS 58/80, 69/80). The therapist assessed the patients and designed their rehabilitation protocol as per their findings of the examination.

OUTCOME

The lower extremity functional scale (LEFS), global rating scale, and VAS were used as outcome variables. The total intervention was given for 10-12 weeks, follow up had been taken for 4 months.

DISCUSSION

The application of dry needling reduced the pain, improved and relieved the symptoms. The eccentric strengthening of the adductors and core stability improved the strength as well as functional activity of the lower limb. The case study is not generalized the effect of treatment. Thus, a randomized control trial is suggested for further study.

Effect of Dry Needling Treatment on Tibial Musculature in Combination with Neurorehabilitation Treatment in Stroke Patients: Randomized Clinical Study

(1) Background: Introducing ultrasound-guided dry needling to neurorehabilitation treatments increases the beneficial effects of therapy. The aim of this study was to compare the effects of including an ultrasound-guided dry needling session in neurorehabilitation treatment on spasticity and gait-balance quality versus neurorehabilitation treatment in subjects who had suffered a stroke. (2) Methods: A single-blind, randomized clinical trial was conducted. Thirty-six patients who had suffered a stroke in the right middle cerebral artery signed the informed consent for participation in the study. Twenty patients finally participated and were randomly assigned to the control group (neurorehabilitation treatment) or experimental group (neurorehabilitation treatment plus ultrasound-guided dry needling). Pre-treatment and post-treatment data were collected on the same day. The experimental group (n = 10) first underwent an ultrasound-guided dry needling intervention on the tibialis anterior and tibialis posterior musculature, followed by neurorehabilitation treatment; the control group (n = 10) underwent their corresponding neurorehabilitation without the invasive technique. Pre-treatment and post-treatment measurements were taken on the same day, assessing the quality of balance-gait using the "Up and Go" test and the degree of spasticity using the Modified Modified Ashworth Scale. (3) Results: The patients who received neurorehabilitation treatment plus ultrasound-guided dry needling showed a greater decrease in spasticity in the tibial musculature after the neurorehabilitation treatment session (p < 0.001), improving balance and gait (p < 0.001). (4) Conclusions: An ultrasound-guided dry needling session combined with neurorehabilitation treatment reduced spasticity and improved balance and gait in stroke patients.

Efficacy of Dry Needling Under EMG Guidance for Myofascial Neck and Shoulder Pain: A Randomized Clinical Trial

Purpose

To determine the difference in maintenance of improvement of pain and disability for dry needling (DN) under needle electromyography (EMG) guidance technique in myofascial neck and shoulder pain patients, compared with DN alone.

Patients and Methods

In this randomized single-blind clinical trial, 30 participants with myofascial pain in the neck and shoulder were randomly allocated to two groups: myofascial trigger points (MTrPs) DN with EMG guided (DN-EMG) group and MTrPs DN without EMG (DN) group. Needling treatment lasted for 2 weeks, twice a week. The primary outcome was pain intensity as assessed by visual analogue scale (VAS) and neck disability index (NDI). A number of mappings referred to pain and spontaneous muscle activity (SEA) were considered secondary outcomes. VAS and NDI were measured before treatment, after 2 weeks of intervention and at 4-, 6- and 12-week follow-up periods after the intervention. Secondary outcomes were assessed before each treatment (T1-T4). Data were analysed using mixed-model analyses of variance (ANOVA) with time as a within-subject variable and groups as between-subject variables followed by Bonferroni's post-hoc test.

Results

Mixed-model ANOVA revealed significant time-by-group interaction effects (F = 3.49, P = 0.01) for VAS. Post-hoc analysis showed a significant decrease in VAS and NDI after 2 weeks of intervention and at all follow-up periods compared with baseline in both groups (p < 0.01). The DN-EMG group exhibited higher improvements in VAS at 6- and 12-week follow-up period than the DN group (p < 0.05). In the SEA of MTrPs, we found positive sharp waves, fibrillation and fascicular potentials. DN-EMG group exhibited lower amplitudes at T2-T4 and frequencies at T2 and T3.

Conclusion

DN under needle EMG guidance technique exhibited greater improvements in maintenance of improvement of pain and lower SEA value than the DN group due to sufficient MTrPs inactivation.

A scoping review of the contralateral effects of unilateral peripheral stimulation on neuromuscular function

It is known that resistance exercise using one limb can affect motor function of both the exercised limb and the unexercised contralateral limb, a phenomenon termed cross-education. It has been suggested that cross-education has clinical implications, e.g. in rehabilitation for orthopaedic conditions or post-stroke paresis. Much of the research on the contralateral effect of unilateral intervention on motor output is based on voluntary exercise. This scoping review aimed to map the characteristics of current literature on the cross-education caused by three most frequently utilised peripheral neuromuscular stimulation modalities in this context: electrical stimulation, mechanical vibration and percutaneous needling, that may direct future research and translate to clinical practice. A systematic search of relevant databases (Ebsco, ProQuest, PubMed, Scopus, Web of Science) through to the end of 2020 was conducted following the PRISMA Extension for Scoping Review. Empirical studies on human participants that applied a unilateral peripheral neuromuscular stimulation and assessed neuromuscular function of the stimulated and/or the unstimulated side were selected. By reading the full text, the demographic characteristics, context, design, methods and major findings of the studies were synthesised. The results found that 83 studies were eligible for the review, with the majority (53) utilised electrical stimulation whilst those applied vibration (18) or needling (12) were emerging. Although the contralateral effects appeared to be robust, only 31 studies claimed to be in the context of cross-education, and 25 investigated on clinical patients. The underlying mechanism for the contralateral effects induced by unilateral peripheral stimulation remains unclear. The findings suggest a need to enhance the awareness of cross-education caused by peripheral stimulation, to help improve the translation of theoretical concepts to clinical practice, and aid in developing well-designed clinical trials to determine the efficacy of cross-education therapies.

Mechanical Needling with Sterile Water versus Steroids Injection for Facet Joint Syndrome: A Retrospective Observational Study

Objective. This present study aimed to explore the clinical effects of ultrasound-guided (USG) mechanical needling with sterile water injection for lumbar facet joint syndrome. Methods. This was a retrospective cohort study that assessed the clinical outcome of ageing patients who received USG mechanical needling with sterile water injection. In addition, the clinical outcome of age- and gender-matched patients randomly selected from patients who received mechanical needling with sterile water was compared to the patients injected with steroids in a 2 : 1 ratio. The data were extracted from the medical records of ageing patients with facet joint syndrome who received USG injection at the lumbosacral spine by the first author. Low back pain or axial pain, and leg pain or radicular pain were assessed by the visual analogue scale (VAS), and gait ability with walking distance was obtained at 6 different time points. Results. A total of 4,276 medical records were examined. Four thousand two hundred twenty-eight ageing patients received needling with sterile water injection and found that the efficacy lasted up to 6 months. Ninety-six patients were compared with 48 patients who received steroid injection. Those who received steroids had less back and leg pain at 1 week after injection; however, pain returned at 3 months and 6 months after injection. Conclusions. USG mechanical needling with sterile water could help relieve axial and radicular pain for at least 6 months. Reduced sensitization and removal of calcification and fibrosis were all possible mechanisms.Keywords: Mechanical needling, Sterile water, Ultrasound guided (USG) injection, Facet joint syndrome, Pain

Evaluation of the Effectiveness of Dry Needling in the Treatment of Myogenous Temporomandibular Joint Disorders

Background and Objectives: The objective of our clinical trial was to determine the effectiveness of the deep dry needling technique (DDN) (neuromuscular deprogramming) as a first step in the treatment of temporomandibular disorders. Methods and Materials: The double-blind randomized clinical trial comprised 36 patients meeting the inclusion criteria who had signed the corresponding informed consent form. The participants were randomly distributed into two groups, the Experimental group (Group E) and the Control group (Group C). Group E received bilateral DDN on the masseter muscle, while Group C received a simulation of the technique (PN). All the participants were evaluated three times: pre-needling, 10 min post-needling, and through a follow-up evaluation after 15 days. These evaluations included, among other tests: pain evaluation using the Visual Analog Scale (VAS) and bilateral muscle palpation with a pressure algometer; evaluation of the opening pattern and range of the mouth, articular sounds and dental occlusion using T-scans; and electromyography, which was used to evaluate the muscle tone of the masseter muscles, in order to control changes in mandibular position. Results: Digital control of occlusion using Tec-Scan (digital occlusion analysis) showed a significant reduction both in the time of posterior disclusion and in the time needed to reach maximum force in an MI position after needling the muscle, which demonstrated that there were variations in the static position and the trajectory of the jaw. The symmetry of the arch while opening and closing the mouth was recovered in a centric relation, with an increase in the opening range of the mouth after the procedure. Conclusions: facial pain is significantly reduced and is accompanied by a notable reduction in muscle activity after needling its trigger points.

Association between subscapularis trigger point and frozen shoulder: A cross sectional study

BACKGROUND

Frozen shoulder (FS) is one of the most common shoulder conditions characterized by pain, restricted range of motion and high morbidity. Though FS is known as adhesive capsulitis, presence of capsular adhesions has been rebutted and the nomenclature adhesive capsulitis is debated. It has been proposed that FS is a condition of cytokine driven capsular, ligamentous fibrosis and contracture. Despite extensive research on it, still it is unclear that how far the capsular contracture contribute to range of motion restriction in FS. Evidence also suggested that myofascial trigger points play a role in restricted range of motion.

OBJECTIVE

To find an association between subscapularis trigger point and frozen shoulder.

STUDY DESIGN

Cross-sectional study.

METHOD

143 Patients were screened for inclusion and exclusion criteria, out of which 100 patients, were selected for the study. Manual palpation was performed to look for subscapularis muscle trigger points via axillary approach on both the affected and unaffected side. Trigger point diagnosing criteria was used to diagnose subscapularis trigger points.

RESULTS

Results have shown that there was an association between subscapularis trigger point and frozen shoulder (X 2 = 32.151 P < 0.0001) on the affected side. We used Phi coefficient to measure the degree of association which denotes (Phi = 0.567 P < 0.0001) strong association between frozen shoulder and subscapularis trigger point on the affected side compared to unaffected side (X 2 9.157; P < 0.002: Phi:0.303: P < 0.002).

CONCLUSION

This study concluded that there appears to be a strong association between subscapularis trigger point and frozen shoulder.

Dry needling has lasting analgesic effect in shoulder pain: a double-blind, sham-controlled trial

Supplemental Digital Content is Available in the Text.

Dry needling has analgesic effects in shoulder pain associated with myofascial pain syndrome. The analgesic effects last for up to 1 week.

Introduction:

Myofascial pain syndrome (MPS) affects most patients with chronic shoulder pain. Dry needling (DN) is a common treatment for MPS, but its temporal pattern and sensory effects remain unknown.

Objectives:

We evaluated in a randomized, sham-controlled study the pattern of analgesic efficacy and local sensory changes of a single session of DN for MPS in patients with chronic shoulder pain.

Methods:

Patients with chronic shoulder pain were randomized into active (n = 20) or sham (n = 21) groups. A single DN was performed by a researcher blinded to group assignment and pain outcomes. Pain intensity was assessed by the numeric rating score, and sensory thresholds were evaluated with a quantitative sensory testing protocol, including the area of tactile sensory abnormalities 7 days before needling, right before, and 7 days after the intervention.

Results:

Dry needling led to significant larger pain intensity reduction (from 6.30 ± 2.05 to 2.40 ± 2.45 in the active group; P = 0.02, effect size = −1.3 (95% CI [−2.0 to −0.68]); (number necessary to treat = 2.1). Pain reduction scores were significantly different on the second day after needling and persisted so until the seventh day and were accompanied by improvement in other dimensions of pain and a decrease in the area of mechanical hyperalgesia in the active DN group alone (P < 0.05).

Conclusion:

Active trigger points DN provided analgesic effects compared with sham and decreased the area of local mechanical hyperalgesia. These findings have practical clinical implications and may provide mechanistic insights behind MPS.

A cartography of energy medicine: From subtle anatomy to energy physiology

The field of energy medicine (EM) is perhaps the most controversial branch of integrative medicine. Its core concept - the existence of an invisible healing energy - has not yet been validated by Western medicine, and the mechanism(s) of action of its techniques have not been fully elucidated. This paper addresses these problems by marshalling several types of evidence: basic science research into electromagnetic fields (EMF), subjective sensations experienced when receiving EM treatments, and clairvoyant perceptions of EM in action. The latter two sources of information, while not solid enough to meet current standards of scientific rigor, can nonetheless generate important new information. A hypothesis is then developed to explain these findings. First, the main components of the human subtle energy system are presented: the "subtle anatomy" of the meridians, of the energy centers and of the biofield. Several representative EM techniques are then analyzed to determine which specific components of that energy structure they impact. Next, EM's mechanisms of action are explored by describing how these altered energy dynamics can affect biologic processes. This subject is termed "energy physiology", in parallel with conventional medicine's foundation in anatomy and physiology. Finally, potential research into energy physiology is outlined that focuses on several common but distinctive experiences which are not fully explained by the current mechanistic biomedical model. Plausible and testable energy-based explanations are proposed for phantom limb pain, emotional entrainment in groups, unusually rapid symptom response to EM, and the invisible templates that guide cell growth and differentiation. This analysis is intended to serve as a guide to future clinical and research explorations into the multidimensional nature of human beings. As Western medicine develops technologies that can generate objective empiric evidence in these subtle domains, we will be able to more fully understand the energetic components of health and illness.

Intramuscular stimulation vs sham needling for the treatment of chronic midportion Achilles tendinopathy: A randomized controlled clinical trial

Background

The insertion of filiform needles intramuscularly (a.k.a. intramuscular stimulation/dry needling) has been suggested as a possible treatment for various painful musculoskeletal conditions. Our aim was to answer the question, is intramuscular stimulation more effective than sham intramuscular stimulation/dry needling for the treatment of Achilles tendinopathy?

Methods

52 participants with persistent midportion Achilles tendinopathy began and 46 completed one of three treatment protocols which were randomly assigned: (G3) a 12-week rehabilitation program of progressive tendon loading plus intramuscular stimulation (n = 25), (G2) the same rehabilitation program but with sham intramuscular stimulation (n = 19), or (G1) a reference group of rehabilitation program alone (as an additional control) (n = 8). The a priori primary outcome measure was change in VISA-A score at 12 weeks–VISA-A was also measured at 6 weeks, and at 6 and 12 months. Secondary outcome measures include the proportion of patients who rated themselves as much or very much improved (%), dorsiflexion range of motion (degrees), and tendon thickness (mm).

Results

The study retention was 94% at 12 weeks and 88% at 1 year. VISA-A score improved in all three groups over time (p<0.0001), with no significant difference among the three groups in VISA-A score at the start of the study (mean ± SD: G3 59 ± 13, G2 57 ± 17, G1 56 ± 22), at 12 weeks (G3 76 ± 14, G2 76 ± 15, G1 82 ± 11) or at any other timepoint. The percentage of patients who rated themselves as much or very much improved (i.e. treatment success) was not different after 12 weeks (G3 70%, G2 89%, G1 86% p = 0.94), or at 26 (p = 0.62) or 52 weeks (p = 0.71). No clinically significant effects of intervention group were observed in any of the secondary outcome measures.

Conclusion

The addition of intramuscular stimulation to standard rehabilitation for Achilles tendinopathy did not result in any improvement over the expected clinical benefit achieved with exercise-based rehabilitation alone.

The effect of dry needling on the active trigger point of upper trapezius muscle: Eliciting local twitch response on long-term clinical outcomes

BACKGROUND

Pain from myofascial trigger points is often treated by dry needling (DN). Empirical evidence suggests eliciting a local twitch response (LTR) during needling is essential. Muscle damage after eliciting LTR can increase the risk of tissue fibrosis in some cases.

OBJECTIVE

This study aimed to compare two methods of DN including with and without LTR on clinical parameters.

METHODS

Twenty-six participants suffering from chronic non-specific neck pain with an active trigger point (TrP) in their upper trapezius muscles were recruited via the convenience sampling method. Participants were randomly assigned in DN with LTR (control group) and without eliciting LTR or "de qi" (experimental group). Then, they received 3 sessions of dry needling, 3 days apart. We evaluated pain, pain pressure threshold, active cervical lateral flexion range of motion, and Neck Disability Index before the intervention and 4 weeks after the treatment.

RESULTS

After the treatment, significant higher changes were seen in the experimental group compared to the control group (p< 0.05) regarding pain, pain pressure threshold, and active cervical lateral flexion. However, there was no significant difference between groups according to the disability (p> 0.05).

CONCLUSION

DN without eliciting LTR has superiority over the DN along with eliciting LTR while the treatment aimed to receive long-term effects.

Understanding Acupoint Sensitization: A Narrative Review on Phenomena, Potential Mechanism, and Clinical Application

As part of traditional Chinese medicine, acupoints are considered a dynamic functional area, which can reflect the internal condition of the body. When the body is suffering from disease or injury, corresponding acupoints are believed to be activated and manifest in several sensitized forms, including expansion of the receptive field, pain sensitization, and heat sensitization. Such phenomena are believed to gradually disappear concomitantly with recovery from the disease. Acupoint states are therefore changeable according to health status, a phenomenon known as acupoint sensitization. This review aims to provide an overview of acupoint sensitization based on existing research results and determine priorities for future research. Systematic literature retrieval was conducted in Medline, Embase, Cochrane Library, CINAHL, and AMED from inception to 18 July 2018. Current evidence from research findings to date indicate that acupoint sensitization is based on neurogenic inflammation and that stimulation of sensitized acupoints presents a potential trend of generating a better clinical effect when compared with stimulation of unsensitized points.

Trigger point dry needling for the treatment of myofascial pain syndrome: current perspectives within a pain neuroscience paradigm

Myofascial pain syndrome is a pain condition characterized by the presence of trigger points. Current evidence, mostly experimental studies, clearly supports a role of trigger points on peripheral and central sensitization since they are able to contribute to sensitization of peripheral nociceptors, spinal dorsal horn neurons, and the brainstem. Several interventions are proposed for treating trigger points, dry needling being one of the most commonly used by clinicians. There is no consensus on the clinical application of trigger point dry needling: some authors propose that local twitch responses should be elicited during the needling intervention to be effective, whereas others do not. The application of trigger point dry needling is able to reduce the excitability of the central nervous system by reducing peripheral nociception associated to the trigger point, by reducing dorsal horn neuron activity, and by modulating pain-related brainstem areas. However, the effects are mainly observed in the short-term, and effect sizes are moderateto small. Therefore, the current review proposes that the application of trigger point dry needling should be integrated into current pain neuroscience paradigm by combining its application with pain neuroscience education, graded exercise and manual therapy. Additionally, patient’s expectations, beliefs, previous experiences and patient–clinician interaction should be considered when integrating trigger point dry needling into a comprehensive treatment approach.

The Construction of Sham Dry Needles and Their Validity

Appropriate control interventions are necessary to show the treatment effect of dry needling. Different control procedures, such as dry needling of the contralateral side, and sham treatments, such as random and superficial needle insertion, have been utilized in trials. However, those methods might elicit a physiological response and are subsequently not ideal for use as a control. This descriptive study illustrates the construction of low-cost sham dry needles and evaluates their validity. Forty-two healthy asymptomatic subjects received either sham or real dry needling intervention to their right gluteal muscles and reported if they felt that the needle pierced the skin. They also graded the severity and qualified (sharp or dull) the pain associated with the intervention. The results showed that most of the subjects in both groups believed the needle penetrated the skin. The quantity of pain associated with the treatment was similar in both groups, but the quality assigned was different. The authors conclude that sham dry needling can be accomplished and used as a valid control treatment in dry needling research using these low-cost sham needles.

SPINAL AND PERIPHERAL DRY NEEDLING VERSUS PERIPHERAL DRY NEEDLING ALONE AMONG INDIVIDUALS WITH A HISTORY OF LATERAL ANKLE SPRAIN: A RANDOMIZED CONTROLLED TRIAL

BACKGROUND

In addition to established interventions, dry needling may reduce impairments leading to greater functional abilities for individuals following ankle sprain.

HYPOTHESIS/PURPOSE

The purpose of this study was to compare effects of spinal and peripheral dry needling (DN) with peripheral DN alone on impairments and functional performance among individuals with a history of lateral ankle sprain.

STUDY DESIGN

Randomized controlled trial.

METHODS

Twenty individuals with a history of lateral ankle sprain (18 bilateral, 2 unilateral) participated in this study (4 males, 16 females; mean age 28.9 + /- 9.2 years). During the first of two sessions, participants completed the Foot and Ankle Disability Index (FADI) and the Cumberland Ankle Instability Tool (CAIT) and their strength, unilateral balance, and unilateral hop test performance was assessed. Participants were randomly assigned to a spinal and peripheral DN group (SPDN), or a peripheral only DN group (PDN). Participants in the SPDN site group received DN to bilateral L5 multifidi and fibularis longus and brevis muscles on the involved lower extremity. Participants in the PDN group received DN to the fibularis muscles alone. Participants' strength, balance and hop test performance were reassessed immediately following the intervention, and at follow-up 6-7 days later, all outcome measures were reassessed. Three-way mixed model ANOVAs and Mann-Whitney U tests assessed between group differences for outcome variables with normal distributions and non-normal distributions, respectively.

RESULTS

ANOVAs showed significant group by time interaction (p<0.05) for invertor strength, significant side by group and time by group interactions (p<0.05) for plantarflexor-evertor strength, no significant findings for dorsiflexor-invertor strength, significant side by time interaction (p<0.05) for unilateral balance, significant main effect of time (p<0.05) for triple hop for distance test, and significant main effect of side (p<0.05) for the CAIT. Mann-Whitney U tests showed no significance (p>0.05) for the side hop test or FADI.

CONCLUSION

The results suggest that DN of the multifidi in addition to fibularis muscles does not result in improvements in strength, unilateral balance or unilateral hop test performance, compared to DN the fibularis muscles alone among individuals with a history of ankle sprain.

Comparison of the Effectiveness of Transcutaneous Electrical Nerve Stimulation and Interferential Therapy on the Upper Trapezius in Myofascial Pain Syndrome: A Randomized Controlled Study

OBJECTIVE

The aim of this study was to compare the effectiveness of transcutaneous electrical nerve stimulation and interferential therapy (IFT) both in combination with hot pack, myofascial release, active range of motion exercise, and a home exercise program on myofascial pain syndrome patients with upper trapezius myofascial trigger point.

DESIGN

A total of 105 patients with an upper trapezius myofascial trigger point were recruited to this single-blind randomized controlled trial. Following random allocation of patients to three groups, three therapeutic regimens-control-standard care (hot pack, active range of motion exercises, myofascial release, and a home exercise program with postural advice), transcutaneous electrical nerve stimulation-standard care and IFT-standard care-were administered eight times during 4 wks at regular intervals. Pain intensity and cervical range of motions (cervical extension, lateral flexion to the contralateral side, and rotation to the ipsilateral side) were measured at baseline, immediately after the first treatment, before the eighth treatment, and 1 wk after the eighth treatment.

RESULTS

Immediate and short-term improvements were marked in the transcutaneous electrical nerve stimulation group (n = 35) compared with the IFT group (n = 35) and the control group (n = 35) with respect to pain intensity and cervical range of motions (P < 0.05). The IFT group showed significant improvement on these outcome measurements than the control group did (P < 0.05).

CONCLUSION

Transcutaneous electrical nerve stimulation with standard care facilitates recovery better than IFT does in the same combination.

The local twitch response during trigger point dry needling: Is it necessary for successful outcomes?

BACKGROUND

Myofascial trigger point (MTrP) injection and trigger point dry needling (TrPDN) are widely accepted therapies for myofascial pain syndrome (MPS). Empirical evidence suggests eliciting a local twitch response (LTR) during needling is essential.

OBJECTIVE

This is the first review exploring the available literature, regardless of study design, on the neurophysiological effects and clinical significance of the LTR as it relates to reductions in pain and disability secondary to MTrP needling.

METHODS

PubMed, MEDLINE, Science Direct and Google Scholar were searched up until October 2016 using terms related to trigger point needling and the LTR.

RESULTS

and Discussion: Several studies show that eliciting a LTR does not correlate with changes in pain and disability, and multiple systematic reviews 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. While the LTR during TrPDN appears unnecessary for managing myofascial pain and unrelated to many of the positive effects of TrPDN, further investigation is required.

Referred Pain Patterns of the Infraspinatus Muscle Elicited by Deep Dry Needling and Manual Palpation

OBJECTIVES

To identify the most common referred pain (ReP) pattern of the infraspinatus myofascial trigger point (MTrP) and compare its coincidence with the original ReP pattern, to verify whether there are any significant differences by sex and types of technique and to determine the observed signs and symptoms evoked by deep dry needling (DDN) and manual palpation (MPal).

DESIGN

A cohort study of patients randomized to two different examination methods (July and August 2016).

SETTINGS

Students and staff recruited from Miguel Hernandez University (Southeast Spain).

PATIENTS

One hundred thirty-three participants (70.7% women) with shoulder complaints were randomly assigned to either an MPal (n = 67) or DDN group (n = 66).

INTERVENTIONS

The same physiotherapist carried out the techniques on all participants, and the same protocol was followed for both the DDN and MPal groups. The physiotherapist did not ask participants about their pain features or other relevant issues.

OUTCOME MEASURES

Local twitch response (LTR) and ReP assessed through a visual analogue scale and features of ReP of the infraspinatus muscle.

RESULTS

The areas with the highest percentage of ReP were the front (area 3; 27.1%) and back (area 11; 21.1%) of the arm, anterior (area 4; 36.1%) and posterior (area 12; 42.1%) shoulder, and infraspinatus muscle area. DDN proved to be significantly easier than MPal in evoking an LTR (p ≤ 0.001). There were significant differences between sexes in zone 2 (p = 0.041) and no statistically significant differences were found by technique.

CONCLUSIONS

The ReP pattern of the infraspinatus muscle coincides with the original pattern described by Travell and Simons, although the neck area should be questioned. The study found no significant differences in the ReP pattern by sex and when comparing MPal with DDN of MTrP of the infraspinatus muscle. DDN proved to be significantly easier than MPal in evoking an LTR.

Beneficial Effects of Dry Needling for Treatment of Chronic Myofascial Pain Persist for 6 Weeks After Treatment Completion

BACKGROUND

Dry needling is an effective treatment for reducing pain associated with active myofascial trigger points (a-MTrPs) in the short term. The duration of the benefits of this treatment have not been fully assessed.

OBJECTIVE

To determine whether the benefits of dry needling (DN) of a-MTrPs are sustained 6 weeks posttreatment.

DESIGN

Follow-up of a prospective study.

SETTING

University.

PARTICIPANTS

A total of 45 patients (13 male and 32 female) with cervical pain >3 months and a-MTrPs in the upper trapezius who completed 3 DN treatments and who were evaluated 6 weeks posttreatment.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Primary outcomes were changes from baseline to follow-up in scores for the verbal analogue scale (VAS), Brief Pain Inventory (BPI), and MTrP status. MTrPs were rated as active (spontaneously painful), latent (painful only on compression), and nonpalpable nodule. Responders were patients whose MTrP status changed from active to latent or nonpalpable nodule (resolved). Secondary outcomes were pain pressure threshold (PPT), Profile of Mood States, Oswestry Disability Index (ODI), MOS 36-Item Short-Form Health Survey (SF-36), and cervical range of motion.

RESULTS

Pain measures remained significantly improved 6 weeks posttreatment (P < .003), as did the SF-36 physical functioning score (0.01) and ODI (P = .002). Side bending and PPT for subjects with unilateral MTrPs had sustained improvement (P = .002). The number of subjects with sustained MTrP response at 6 weeks was significant (P < .001). Comparing responders to nonresponders, the changes in VAS and BPI were statistically significant (P = .006, P = .03) but the change in PPT was not. Patients with higher baseline VAS scores had a higher risk of not responding to DN; those with a greater drop in VAS score from baseline had a higher probability of sustained response. A 1-unit decrease in VAS at baseline resulted in a 6.3-fold increase in the odds of being a responder versus a nonresponder (P = .008).

CONCLUSIONS

In this study, there was sustained reduction of pain scores after completion of DN, which is more likely with a greater drop in VAS score. Patients with higher baseline VAS scores are less likely to respond to DN. Early intervention toward significant pain reduction is likely to be associated with sustained clinical response.

LEVEL OF EVIDENCE

IV.

Dry needling for management of pain in the upper quarter and craniofacial region

Dry needling is a therapeutic intervention that has been growing in popularity. It is primarily used with patients that have pain of myofascial origin. This review provides background about dry needling, myofascial pain, and craniofacial pain. We summarize the evidence regarding the effectiveness of dry needling. For patients with upper quarter myofascial pain, a 2013 systematic review and meta-analysis of 12 randomized controlled studies reported that dry needling is effective in reducing pain (especially immediately after treatment) in patients with upper quarter pain. There have been fewer studies of patients with craniofacial pain and myofascial pain in other regions, but most of these studies report findings to suggest the dry needling may be helpful in reducing pain and improving other pain related variables such as the pain pressure threshold. More rigorous randomized controlled trials are clearly needed to more fully elucidate the effectiveness of dry needling.

A critical evaluation of Quintner et al: missing the point

The objective of this article is to critically analyze a recent publication by Quinter, Bove and Cohen, published in Rheumatology, about myofascial pain syndrome and trigger points (Quintner et al., 2014). The authors concluded that the leading trigger point hypothesis is flawed in reasoning and in science. They claimed to have refuted the trigger point hypothesis. The current paper demonstrates that the Quintner et al. paper is a biased review of the literature replete with unsupported opinions and accusations. In summary, Quintner et al. have not presented any convincing evidence to believe that the Integrated TrP Hypothesis should be laid to rest.

Dry needling: a literature review with implications for clinical practice guidelines

BACKGROUND

Wet needling uses hollow-bore needles to deliver corticosteroids, anesthetics, sclerosants, botulinum toxins, or other agents. In contrast, dry needling requires the insertion of thin monofilament needles, as used in the practice of acupuncture, without the use of injectate into muscles, ligaments, tendons, subcutaneous fascia, and scar tissue. Dry needles may also be inserted in the vicinity of peripheral nerves and/or neurovascular bundles in order to manage a variety of neuromusculoskeletal pain syndromes. Nevertheless, some position statements by several US State Boards of Physical Therapy have narrowly defined dry needling as an 'intramuscular' procedure involving the isolated treatment of 'myofascial trigger points' (MTrPs).

OBJECTIVES

To operationalize an appropriate definition for dry needling based on the existing literature and to further investigate the optimal frequency, duration, and intensity of dry needling for both spinal and extremity neuromusculoskeletal conditions.

MAJOR FINDINGS

According to recent findings in the literature, the needle tip touches, taps, or pricks tiny nerve endings or neural tissue (i.e. 'sensitive loci' or 'nociceptors') when it is inserted into a MTrP. To date, there is a paucity of high-quality evidence to underpin the use of direct dry needling into MTrPs for the purpose of short and long-term pain and disability reduction in patients with musculoskeletal pain syndromes. Furthermore, there is a lack of robust evidence validating the clinical diagnostic criteria for trigger point identification or diagnosis. High-quality studies have also demonstrated that manual examination for the identification and localization of a trigger point is neither valid nor reliable between-examiners.

CONCLUSIONS

Several studies have demonstrated immediate or short-term improvements in pain and/or disability by targeting trigger points (TrPs) using in-and-out techniques such as 'pistoning' or 'sparrow pecking'; however, to date, no high-quality, long-term trials supporting in-and-out needling techniques at exclusively muscular TrPs exist, and the practice should therefore be questioned. The insertion of dry needles into asymptomatic body areas proximal and/or distal to the primary source of pain is supported by the myofascial pain syndrome literature. Physical therapists should not ignore the findings of the Western or biomedical 'acupuncture' literature that have used the very same 'dry needles' to treat patients with a variety of neuromusculoskeletal conditions in numerous, large scale randomized controlled trials. Although the optimal frequency, duration, and intensity of dry needling has yet to be determined for many neuromusculoskeletal conditions, the vast majority of dry needling randomized controlled trials have manually stimulated the needles and left them in situ for between 10 and 30 minute durations. Position statements and clinical practice guidelines for dry needling should be based on the best available literature, not a single paradigm or school of thought; therefore, physical therapy associations and state boards of physical therapy should consider broadening the definition of dry needling to encompass the stimulation of neural, muscular, and connective tissues, not just 'TrPs'.

Efficacy of myofascial trigger point dry needling in the prevention of pain after total knee arthroplasty: a randomized, double-blinded, placebo-controlled trial

The aim of this study was to determine whether the dry needling of myofascial trigger points (MTrPs) is superior to placebo in the prevention of pain after total knee arthroplasty. Forty subjects were randomised to a true dry needling group (T) or to a sham group (S). All were examined for MTrPs by an experienced physical therapist 4-5 hours before surgery. Immediately following anesthesiology and before surgery started, subjects in the T group were dry needled in all previously diagnosed MTrPs, while the S group received no treatment in their MTrPs. Subjects were blinded to group allocation as well as the examiner in presurgical and follow-up examinations performed 1, 3, and 6 months after arthroplasty. Subjects in the T group had less pain after intervention, with statistically significant differences in the variation rate of the visual analogue scale (VAS) measurements 1 month after intervention and in the need for immediate postsurgery analgesics. Differences were not significant at 3- and 6-month follow-up examinations. In conclusion, a single dry needling treatment of MTrP under anaesthesia reduced pain in the first month after knee arthroplasty, when pain was the most severe. Results show a superiority of dry needling versus placebo. An interesting novel placebo methodology for dry needling, with a real blinding procedure, is presented.

Electrophysiologic evidence of spinal accessory neuropathy in patients with cervical myofascial pain syndrome

OBJECTIVE

To evaluate whether or not spinal accessory neuropathy exists in patients with cervical myofascial pain syndrome (MFPS).

DESIGN

Prospective study.

SETTING

A neurophysiologic laboratory in a university hospital.

PARTICIPANTS

Patients with cervical MFPS (n=25) and healthy controls (n=20).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

We performed nerve conduction studies (NCSs) in bilateral spinal accessory nerves, and electromyography and stimulated single-fiber electromyography in the trapezius muscles of all patients and controls. Parameters including nerve conduction velocities (NCVs), amplitudes and areas of compound muscle action potentials (CMAPs), and mean consecutive differences (MCDs) in single-fiber electromyography were measured, analyzed, and compared with the disease durations of the patients.

RESULTS

Spinal accessory NCSs showed normative NCVs but with prominently reduced CMAP amplitude in the patients with cervical MFPS, which is recognized as an axonal neuropathy of the spinal accessory nerves. Electromyography showed prominent evidence of denervation and reinnervation patterns in 48% of the MFPS patients. The abnormal MCDs in single-fiber electromyography indicated a synaptic delay of motor endplates in the motor units, and may signify evolving instability of neuromuscular transmission in the spinal accessory nerves innervating trapezius muscles of the patients.

CONCLUSIONS

This study demonstrates electrophysiologic evidence of neuroaxonal degeneration and neuromuscular transmission disorder in a significant proportion of patients with cervical MFPS. We suggest that spinal accessory neuropathy may be associated with cervical MFPS.

Interrater reliability of palpation of myofascial trigger points in three shoulder muscles

This observational study included both asymptomatic subjects (n=8) and patients with unilateral or bilateral shoulder pain (n=32). Patient diagnoses provided by the referring medical physicians included subacromial impingement, rotator cuff disease, tendonitis, tendinopathy, and chronic subdeltoid-subacromial bursitis. Three raters bilaterally palpated the infraspinatus, the anterior deltoid, and the biceps brachii muscles for clinical characteristics of a total of 12 myofascial trigger points (MTrPs) as described by Simons et al. The raters were blinded to whether the shoulder of the subject was painful. In this study, the most reliable features of trigger points were the referred pain sensation and the jump sign. Percentage of pair-wise agreement (PA) was >/= 70% (range 63-93%) in all but 3 instances for the referred pain sensation. For the jump sign, PA was >/= 70% (range 67-77%) in 21 instances. Finding a nodule in a taut band (PA = 45-90%) and eliciting a local twitch response (PA = 33-100%) were shown to be least reliable. The best agreement about the presence or absence of MTrPs was found for the infraspinatus muscle (PA = 69-80%). This study provides preliminary evidence that MTrP palpation is a reliable and, therefore, potentially useful diagnostic tool in the diagnosis of myofascial pain in patients with non-traumatic shoulder pain.

Involvement of NGF in the rat model of persistent muscle pain associated with taut band

Myofascial pain syndrome (MPS) is an important clinical condition characterized by chronic muscle pain and a myofascial trigger point (MTrP) located in a taut band (TB). However, its pathogenic mechanism is still unclear. We developed an animal model relevant to conditions of MPS, and analyzed the mechanism of the muscle pain in this model. We applied eccentric contraction (EC) to a rat's gastrocnemius muscle (GM) for 2 weeks, and examined the mechanical withdrawal thresholds, histological changes, and expressions and contents of nerve growth factor (NGF). The mechanical withdrawal threshold decreased significantly at the next day of first EC and continued up to 9 days after EC. TBs were palpable at 3 to 8 days after initiation of EC. In EC animals, necrotic and regenerating muscle cells were found significantly more than in control animals. In EC animals, NGF expressions in regenerating muscle cells and NGF contents of GM were significantly higher than control animals. Administration of NGF receptor (TrkA) inhibitor K252a showed significant suppression of mechanical hyperalgesia in EC animals. Repeated EC induced persistent mechanical muscle hyperalgesia associated with TB. NGF expressed in regenerating muscle cells may have an important role in persistent mechanical muscle hyperalgesia which might be relevant to pathogenesis of MPS.

PERSPECTIVE

The present study shows that NGF expressed in regenerating muscle cells is involved in persistent muscular mechanical hyperalgesia. NGF-TrkA signaling in primary muscle afferent neurons may be one of the most important and promising targets for MPS.

Endogenous descending modulation: spatiotemporal effect of dynamic imbalance between descending facilitation and inhibition of nociception

In conscious rats, we investigated the change of nociceptive paw withdrawal reflexes elicited by mechanical and heat stimuli during intramuscular (i.m.) 5.8% hypertonic (HT) saline elicited muscle nociception. i.m. injection of HT saline caused rapid onset, long lasting (around 7 days), bilateral mechanical hyperalgesia, while it induced bilateral, slower onset (1 day after the HT saline injection), long-term (about 1-2 weeks) heat hypoalgesia. Ipsilateral topical pre-treatment of the sciatic nerve with 1% capsaicin significantly prevented the occurrence of both the bilateral mechanical hyperalgesia and the contralateral heat hypoalgesia. Intrathecal administration of either 6-hydroxydopamine hydrobromide (6-OHDA) or 5,7-dihydroxytryptamine (5,7-DHT), and intraperitoneal injection of naloxone all markedly attenuated the HT saline induced bilateral heat hypoalgesia, but not the mechanical hyperalgesia. Combined with experiments with lesioning of the rostroventral medulla with kainic acid, the present data indicate that unilateral i.m. injection of HT saline elicits time-dependent bilateral long-term mechanical hyperalgesia and heat hypoalgesia, which were modulated by descending facilitatory and inhibitory controls, respectively. We hypothesize that supraspinal structures may function to discriminate between afferent noxious inputs mediated by Aδ- and C-fibres, either facilitating Aδ-fibre mediated responses or inhibiting C-fibre mediated activities. However, this discriminative function is physiologically silent or inactive, and can be triggered by stimulation of peripheral C-fibre afferents. Importantly, in contrast to the rapid onset of descending facilitation, the late occurrence of descending inhibition suggests a requirement of continuous C-fibre input and temporal summation. Thus, a reduction of C-fibre input using exogenous analgesic agents, i.e. opioids, may counteract the endogenous descending inhibition.

Immediate effect of electric point stimulation (TENS) in treating latent upper trapezius trigger points: a double blind randomised placebo-controlled trial

OBJECTIVE

The purpose of this study was to investigate the immediate effect of electric point stimulation in treating latent upper trapezius trigger points compared to placebo.

DESIGN

Double blind randomised placebo-controlled trial.

SETTING

Anglo-European College of Chiropractic.

PARTICIPANTS

Sixty participants with latent upper trapezius trigger points.

INTERVENTIONS

Electric point stimulator type of TENS, or detuned (inactive) electric point stimulator type of TENS.

MAIN OUTCOME MEASURES

The three outcome measures were pressure pain threshold at the trigger point, a numerical rating scale for pain elicited over the trigger point, and lateral cervical flexion to the side opposite the trigger point.

RESULTS

On the outcome of pressure pain threshold the electric point stimulator group had a mean change of 0.49 (0.99) kg/cm(2), while the placebo group had a mean change of 0.45 (0.98) kg/cm(2) (t = 0.16, df = 58, p = 0.88). For change in pain over the trigger point, the electric point stimulator group had a mean decrease of 0.93 (0.87) points, while the placebo group had a mean decrease of 0.23 (0.97) points (t = 0.70, df = 58, p = 0.005). On the outcome of change in lateral cervical flexion the electric point stimulator group had a mean increase of 2.87 (4.55) degrees, while the placebo group had a mean increase of 1.99 (2.49) degrees (t = 0.92, df = 58, p = 0.36).

CONCLUSION

Electric point stimulator type of TENS is superior to placebo only in reduction of pain for treating latent upper trapezius trigger points.

Bilateral acupuncture analgesia observed by quantitative sensory testing in healthy volunteers

BACKGROUND

There is evidence that acupuncture activates different spinal and supraspinal antinociceptive systems, but the specific modulatory effects on the sensory system have not been systematically investigated. In this study, we evaluated the immediate effects of different types of acupuncture on thermal, mechanical, and vibratory sensory thresholds.

METHODS

Twenty-four healthy volunteers (12 men and 12 women, mean age 33.1 years) received 3 different forms of acupuncture in a single-blinded crossover design; these included manual acupuncture, acupuncture with low-frequency electrical stimulation, and acupuncture with high-frequency electrical stimulation. The time between the interventions was 1 week. All forms of acupuncture were applied unilaterally in the leg at standard acupuncture points: spleen 6, spleen 9, stomach 36, and gallbladder 39. The effects of acupuncture were evaluated by systematic quantitative sensory testing (QST) immediately after each intervention. QST was performed on bilateral lower extremities, including thermal and mechanical perception and pain and vibratory thresholds.

RESULTS

The heat pain threshold was increased after manual acupuncture on the treated and untreated side compared with baseline. Low- and high-frequency electrostimulation led to a higher mechanical pain threshold on the treated side compared with baseline and manual acupuncture. The pressure pain threshold was increased by all forms of acupuncture on both sides, with individual changes from baseline ranging from 25% to 52%.

CONCLUSIONS

There were congruent changes on QST after 3 common acupuncture stimulation methods, with possible unilateral as well as bilateral effects.

The immediate effects of local and adjacent acupuncture on the tibialis anterior muscle: a human study

Background

This study compares the immediate effects of local and adjacent acupuncture on the tibialis anterior muscle and the amount of force generated or strength in Kilogram Force (KGF) evaluated by a surface electromyography.

Methods

The study consisted of a single blinded trial of 30 subjects assigned to two groups: local acupoint (ST36) and adjacent acupoint (SP9). Bipolar surface electrodes were placed on the tibialis anterior muscle, while a force transducer was attached to the foot of the subject and to the floor. An electromyograph (EMG) connected to a computer registered the KGF and root mean square (RMS) before and after acupuncture at maximum isometric contraction. The RMS values and surface electrodes were analyzed with Student's t-test.

Results

Thirty subjects were selected from a total of 56 volunteers according to specific inclusion and exclusion criteria and were assigned to one of the two groups for acupuncture. A significant decrease in the RMS values was observed in both ST36 (t = -3.80, P = 0,001) and SP9 (t = 6.24, P = 0.001) groups after acupuncture. There was a decrease in force in the ST36 group after acupuncture (t = -2.98, P = 0.006). The RMS values did not have a significant difference (t = 0.36, P = 0.71); however, there was a significant decrease in strength after acupuncture in the ST36 group compared to the SP9 group (t = 2.51, P = 0.01). No adverse events were found.

Conclusion

Acupuncture at the local acupoint ST36 or adjacent acupoints SP9 reduced the tibialis anterior electromyography muscle activity. However, acupuncture at SP9 did not decrease muscle strength while acupuncture at ST36 did.

Topographical mapping and mechanical pain sensitivity of myofascial trigger points in the infraspinatus muscle

OBJECTIVES

To screen for the presence of latent and active myofascial trigger points (MTrPs) in patients with unilateral shoulder and arm pain and perform topographical mapping of mechanical pain sensitivity bilaterally in the infraspinatus muscles.

METHODS

Nineteen patients with unilateral musculoskeletal shoulder pain participated in the study. The area overlying the infraspinatus on each side was divided into 10 adjacent sub-areas of 1cm(2), corresponding to the area of a pressure algometer probe. Pressure pain threshold (PPT) was measured in each sub-area bilaterally in the infraspinatus muscles. Following PPT measurement, an acupuncture needle was inserted into each sub-area five times in different directions in order to induce local twitch response and/or referred pain.

RESULTS

A significantly lower PPT level in the infraspinatus muscle was detected on the painful side compared with the non-painful side (P=0.001). PPT at midfiber region of the infraspinatus muscles was lower than that at other muscle parts (P<0.05). Multiple, but not single, active MTrPs were found in the infraspinatus muscle on the painful side and there were also multiple latent MTrPs bilaterally in the infraspinatus muscles. PPT at active MTrPs was much lower than the latent MTrPs and again lower than the non-MTrPs.

CONCLUSIONS

There exists bilateral mechanical hyperalgesia in patients with unilateral shoulder pain. Further, the association of multiple active MTrPs with unilateral shoulder pain and the heterogeneity of mechanical pain sensitivity distribution suggest a crucial role of peripheral sensitization in chronic myofascial pain conditions. Additionally, the locations of MTrPs identified with dry needling correspond well to PPT topographical mapping, suggesting that dry needling and PPT topographical mapping are sensitive techniques in the identification of MTrPs.

The short-term effects of acupuncture on myofascial pain patients after clenching

AIM

Short-term pain reduction from acupuncture in chronic myofascial pain subjects was evaluated using an 11-point (0 to 10) numeric rating scale, visual analog scale (VAS), and pain rating of mechanical pressure on the masseter muscle.

METHODS

A single-blind, randomized, controlled, clinical trial with an independent observer was performed. Fifteen chronic myofascial pain subjects over the age of 18 were randomly assigned into groups: nine subjects received real acupuncture; six subjects received sham acupuncture. Each subject clenched his/her teeth for 2 minutes. Acupuncture or sham acupuncture was administered at the Hegu Large Intestine 4 acupoint. Sham acupuncture was conducted by lightly pricking the skin with a shortened, blunted acupuncture needle through a foam pad, without penetrating the skin. The foam pad visually conceals the needle's point of the entry, so that the subject cannot discern which technique is being used. The subjects rated their general pain on a numeric rating scale. A mechanical pain stimulus was applied with an algometer and the subject rated his/her pain on a VAS. Statistical analysis was performed using the repeated measures anova, paired t-tests, and Fisher's exact test as appropriate.

RESULTS

There was a statistically significant difference in pain tolerance with acupuncture (P = 0.027). There was statistically significant reduction in face pain (P = 0.003), neck pain (P = 0.011), and headache (P = 0.015) with perception of real acupuncture.

CONCLUSION

Pain tolerance in the masticatory muscles increased significantly more with acupuncture than sham acupuncture.

Myofascial pain syndromes and their evaluation

Myofascial pain refers to a specific form of soft-tissue rheumatism that results from irritable foci (trigger points) within skeletal muscles and their ligamentous junctions. It must be distinguished from bursitis, tendonitis, hypermobility syndromes, fibromyalgia and fasciitis. On the other hand it often exists as part of a clinical complex that includes these other soft-tissue conditions, i.e., it is not a diagnosis of exclusion. The clinical science of trigger points can be traced to the pioneering work of Kellgren in the 1930s, with his mapping of myotomal referral patterns of pain resulting from the injection of hypertonic saline into muscle and ligaments. Most muscles have characteristic myotomal patterns of referred pain; this feature forms the basis of the clinical recognition of myofascial trigger points in the form of a tender locus within a taut band of muscle which restricts the full range of motion and refers pain centrifugally when stimulated. Although myofascial pain syndromes have been described in the medical literature for about the last 100 years, it is only recently that scientific studies have revealed objective abnormalities.

Variability of Criteria Used to Diagnose Myofascial Trigger Point Pain Syndrome—Evidence From a Review of the Literature

OBJECTIVES

The aim of the literature review was to investigate the criteria adopted by "experts" to diagnose myofascial trigger point (MTrP) pain syndrome. Experts were defined as being either researchers investigating MTrP pain syndrome or the "authority" the researchers cited as a source of reference for MTrP pain syndrome diagnosis.

METHODS

We searched electronic databases to identify relevant empirical research (excluding studies not in English and those relating to dental pathology). Of 607 possibly relevant publications 93 met our inclusion criteria. We recorded (1) the individual criterion and criteria combinations used to diagnose MTrP pain syndrome; (2) the cited "authoritative" publications and (3) the criteria recommended by the authoritative publications as being essential for MTrP pain syndrome diagnosis.

RESULTS

The review identified 19 different diagnostic criteria. The 4 most commonly applied criteria were: "tender spot in a taut band" of skeletal muscle, "patient pain recognition," "predicted pain referral pattern," and "local twitch response." There was no consistent pattern to the choice of specific diagnostic criteria or their combinations. However, one pair of criteria "tender point in a taut band" and "predicted or recognized pain referral" were used by over half the studies. The great majority of studies cited publications by Travell and more recently Simons as a principal authoritative source for MTrP pain syndrome diagnosis, yet most of these studies failed to apply the diagnostic criteria as described by these authorities.

DISCUSSION

We conclude that there is as yet limited consensus on case definition in respect of MTrP pain syndrome. Further research is needed to test the reliability and validity of diagnostic criteria. Until reliable diagnostic criteria have been established, there is a need for greater transparency in research papers on how a case of MTrP pain syndrome is defined, and claims for effective interventions in treating the condition should be viewed with caution.

Physical medicine rehabilitation approach to pain

A physical medicine and rehabilitation approach to acute and chronic pain syndromes includes a wide spectrum of treatment focus. Whether assessing or treating acute or chronic pain syndromes, management should include a biopsychosocial approach. Assessment may include a focused joint and functional examination including more global areas of impairment (ie, gait, balance, and endurance) and disability. More complicated multidimensional chronic pain conditions may require the use of a more collaborative continuum of multidisciplinary and interdisciplinary treatment approaches. Regardless of the scope of care that each individual patient requires, treatment options may include active physical therapy, rational polypharmacy, CBT, and the use of passive modalities. Treatment goals generally emphasize achieving analgesia, improving psychosocial functioning, and reintegration of recreational or leisure pursuits (ie, community activities and sports). Progress in all therapies necessitates close monitoring by the health care provider and necessitates ongoing communication between members of the treatment team. Although this article focuses on diagnoses related to acute and chronic low back pain, OA, and musculoskeletal disorders, assessment and treatment recommendations may be generalized to most other pain conditions.

Neuropathic low back pain

In this discussion, we hope to advance a clinical approach to low back pain that is more in line with our modern understanding of neuropathic pain. We review the current understanding of normal and pathologic neuroanatomy of the lumbar spine and then outline how pathology in the different structures can lead to neuropathic pain and cause common pain patterns seen in clinical practice. We also detail the available treatments for neuropathic low back pain.