Dry needling to a key myofascial trigger point may reduce the irritability of satellite MTrPs

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 (randomized). Fourteen patients with bilateral shoulder pain and active MTrPs in bilateral infraspinatus muscles were involved. An MTrP in the infraspinatus muscle on a randomly 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.     

Proximal myofascial pain in patients with distal complex regional pain syndrome of the upper limb

BackgroundPatients suffering from complex regional pain syndrome (CRPS) endure myofascial-related pain in at least 50% of cases.AimsTo evaluate the association of upper limb CRPS with myofascial pain in muscles that might influence arm or hand pain, and to evaluate whether the paraspinal skin and subcutaneous layers’ tenderness and allodynia are associated with CRPS.MethodsA case-control study comprising 20 patients presenting with upper limb CRPS, and 20 healthy controls matched for sex and age, were evaluated in the thoracic paraspinal area and myofascial trigger points (MTrPs) (infraspinatus, rhomboids, subclavius, serratus posterior superior and pectoralis minor) via a skin rolling test.ResultsThe prevalence of MTrPs in the affected extremity of the subjects was significantly higher than in the right limb of the controls: 45% exhibited active and latent MTrPs in the infraspinatus muscle (χ² = 11.613, p = 0.001); 60% in active and latent MTrPs in the subclavius muscle (χ² = 17.143, p < 0.001); and in the pectoralis minor muscle (χ2 = 13.786, p < 0.001). In addition, 55% of the cases exhibited active and latent MTrPs in the serratus posterior superior muscle (χ² = 15.172, p < 0.001). Significant differences between the groups in skin texture and pain levels (p = 0.01, p < 0.001, respectively) demonstrated that CRPS patients felt more pain, and their skin and subcutaneous layers were much tighter than in the healthy controls.ConclusionThere is a high prevalence of MTrPs in the shoulder and upper thoracic area muscles in subjects who suffer from CRPS. We recommend adding an MTrPs evaluation to the standardized examination of these patients.     

Bilateral activation of motor unit potentials with unilateral needle stimulation of active myofascial trigger points

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 prospectively. 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 bands 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.     

Attenuated Skin Blood Flow Response to Nociceptive Stimulation of Latent Myofascial Trigger Points

Zhang Y, Ge H-Y, Yue S-W, Kimura Y, Arendt-Nielsen L. Attenuated skin blood flow response to nociceptive stimulation of latent myofascial trigger points.

Objectives

To investigate the effect of painful stimulation of latent myofascial trigger points (MTrPs) on skin blood flow and to evaluate the relative sensitivity of laser Doppler flowmetry (LDF) and thermography in the measurement of skin blood flow.

Design

Painful stimulation was obtained by a bolus injection of glutamate (0.1mL, 0.5M) into a latent MTrP located in the right or left brachioradialis muscles. A bolus of glutamate injection into a non-MTrP served as control. Pain intensity (visual analog scale [VAS]) was assessed after glutamate injection. Pressure pain threshold (PPT) was recorded bilaterally in the brachioradialis muscle before and after glutamate-induced pain. Skin blood flow and surface skin temperature were measured bilaterally in the forearms before, during, and after glutamate-induced pain with LDF and thermography.

Setting

A biomedical research facility.

Participants

Fifteen healthy volunteer subjects.

Interventions

Not applicable.

Main Outcome Measures

VAS, PPT, skin blood flow, and surface skin temperature.

Results

Glutamate injection into latent MTrPs induced higher pain intensity (F=7.16; P<.05) and lower PPT (F=11.41, P<.005) than into non-MTrPs. Glutamate injection into non-MTrPs increased skin blood flow bilaterally in the forearms, but skin blood flow after glutamate injection into latent MTrPs was significantly less increased at the local injection area or decreased at distant areas compared with non-MTrPs (all P<.05). Skin temperature was not affected after glutamate injection into either latent MTrPs or non-MTrPs (all P>.05).

Conclusions

The present study demonstrated an attenuated skin blood flow response after painful stimulation of latent MTrPs compared with non-MTrPs, suggesting increased sympathetic vasoconstriction activity at latent MTrPs. Additionally, LDF was more sensitive than thermography in the detection of the changes in skin blood flow after intramuscular nociceptive stimulation.     

Dry needling of the trapezius muscle in office workers with neck pain: a randomized clinical trial

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 aimed to determine the effectiveness of deep dry needling (DDN) of active MTrPs in the trapezius muscle.

Methods: A randomized, 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 randomly 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?P?P?P?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.     

Sustained Nociceptive Mechanical Stimulation of Latent Myofascial Trigger Point Induces Central Sensitization in Healthy Subjects

The aim of the study is to test if sustained nociceptive mechanical stimulation (SNMS) of latent myofascial trigger points (MTrPs) induces widespread mechanical hyperalgesia. SNMS was obtained by inserting and retaining an intramuscular electromyographic (EMG) needle within a latent MTrP or a nonMTrP in the finger extensor muscle for 8 minutes in 12 healthy subjects. Pain intensity (VAS) and referred pain area induced by SNMS were recorded. Pressure pain threshold (PPT) was measured immediately before and after, and 10-, 20-, and 30-minutes after SNMS at the midpoint of the contralateral tibialis anterior muscle. Surface and intramuscular EMG during SNMS were recorded. When compared to nonMTrPs, maximal VAS and the area under VAS curve (VASauc) were significantly higher and larger during SNMS of latent MTrPs (both, P < .05); there was a significant decrease in PPT 10 minutes, 20 minutes, and 30 minutes postSNMS of latent MTrPs (all, P < .05). Muscle cramps following SNMS of latent MTrPs were positively associated with VASauc (r = .72, P = .009) and referred pain area (r = .60, P = .03). Painful stimulation of latent MTrPs can initiate widespread central sensitization. Muscle cramps contribute to the induction of local and referred pain.     

The prevalence of myofascial trigger points in hip and thigh areas in anterior knee pain patients

BackgroundAnterior knee pain (AKP) is a widespread problem among young athletes and soldiers. There are many theories on the etiology of AKP but there is little reference to myofascial trigger points (MTrPs) as a possible contributor.AimTo evaluate the association between AKP and prevalence of active and latent MTrPs in the hip and thigh muscles in soldiers.MethodsA cross-sectional study was conducted in the Beer-Sheva military outpatient physical therapy clinic. Subjects were 42 men and 23 women referred for physical therapy, 33 with a diagnosis of AKP (cases) and 32 with upper limb complaints (without AKP, controls). All subjects underwent physical evaluation by an examiner blinded to their identity and medical condition. The following muscles were assessed bilaterally for active or latent MTrPs: rectus femoris (proximal), vastus medialis (middle and distal), vastus lateralis (middle and distal) and gluteus medius (anterior, posterior and distal).ResultsIn six out of eight areas, the cases had a higher prevalence of total active and latent MTrPs than the controls. When summarizing MTrPs by muscle, cases had significantly more MTrPs than controls in each muscle. The largest difference was found in vastus medialis and vastus lateralis; nearly half of the cases had MTrPs in these muscles.ConclusionsSubjects with AKP have a greater prevalence of MTrPs in their hip and thigh muscles than controls, indicating an association between MTrPs and AKP. Further research is necessary to determine whether MTrPs are the cause or the consequence of AKP.     

Short-term effect of myofascial trigger point dry-needling in patients with Adhesive Capsulitis

BackgroundAdhesive Capsulitis (AC) is a common disabling musculoskeletal pain condition of unknown etiology related to the shoulder joint. Literature reported the restricted range of motion (ROM) and pain could be the result of myofascial trigger points (MTrPs) in the muscles of the shoulder girdle. Hence, the objective of this study was to assess the short-term effectiveness of MTrP dry needling (DN) in improving ROM, pain, pressure pain threshold (PPT), and physical disability among patients having AC.MethodsIn a single group pre-post experimental study design, a total of 70 clinically diagnosed patients (both male & female, age group between 40 and 65 years) with AC were recruited from three multi-specialty hospitals. The informed consent forms were received from each patient before participating in the study. Each patient received DN for the MTrPs of shoulder girdle muscles for alternative six days. In addition to DN, each patient had received conventional physiotherapy for continuous twelve days which includes electrotherapy modalities and exercises. The pain intensity (visual analog scale), shoulder ROM (Goniometer), disability (shoulder pain and disability index) and PPT (Algometer) were the outcome measures assessed at the baseline and twelfth day of the intervention.ResultsThere was a statistically significant (p < 0.05) improvement in shoulder ROM, pain intensity, shoulder disability, and PPT at the end of the twelve days of intervention as compared to baseline assessment.ConclusionMTrPs-DN techniques may improve the pain, ROM, disability and PPT along with conventional physiotherapy management among patients with AC.     

Myofascial Trigger Points,Pain, Disability,and Sleep Quality in Individuals With Mechanical Neck Pain

ObjectiveThe purpose of this study was to investigate the presence of active myofascial trigger points (MTrPs) in a greater number of muscles than previous studies and the relation between the presence of MTrPs, the intensity of pain, disability, and sleep quality in mechanical neck pain.MethodsFifteen patients with mechanical neck pain (80% women) and 12 comparable controls participated. Myofascial trigger points were bilaterally explored in the upper trapezius, splenius capitis, semispinalis capitis, sternocleidomastoid, levator scapulae, and scalene muscles in a blinded design. Myofascial trigger points were considered active if the subject recognized the elicited referred pain as a familiar symptom. Myofascial trigger points were considered latent if the elicited referred pain was not recognized as a symptom. Pain was collected with a numerical pain rate scale (0-10); disability was assessed with Neck Disability Index; and sleep quality, with the Pittsburgh Sleep Quality Index.ResultsPatients exhibited a greater disability and worse sleep quality than controls (P < .001). The Pittsburgh Sleep Quality Index score was associated with the worst intensity of pain (r = 0.589; P = .021) and disability (r = 0.552; P = .033). Patients showed a greater (P = .002) number of active MTrPs (mean, 2 ± 2) and similar number (P = .505) of latent MTrPs (1.6 ± 1.4) than controls (latent MTrPs, 1.3 ± 1.4). No significant association between the number of latent or active MTrPs and pain, disability, or sleep quality was found.ConclusionsThe referred pain elicited by active MTrPs in the neck and shoulder muscles contributed to symptoms in mechanical neck pain. Patients exhibited higher disability and worse sleep quality than controls. Sleep quality was associated with pain intensity and disability. No association between active MTrPs and the intensity of pain, disability, or sleep quality was found.     

Changes in pain and pressure pain sensitivity after manual treatment of active trigger points in patients with unilateral shoulder impingement: a case series

The aim of this case series was to investigate changes in pain and pressure pain sensitivity after manual treatment of active trigger points (TrPs) in the shoulder muscles in individuals with unilateral shoulder impingement. Twelve patients (7 men, 5 women, age: 25 ± 9 years) diagnosed with unilateral shoulder impingement attended 4 sessions for 2 weeks (2 sessions/week). They received TrP pressure release and neuromuscular interventions over each active TrP that was found. The outcome measures were pain during arm elevation (visual analogue scale, VAS) and pressure pain thresholds (PPT) over levator scapulae, supraspinatus infraspinatus, pectoralis major, and tibialis anterior muscles. Pain was captured pre-intervention and at a 1-month follow-up, whereas PPT were assessed pre- and post-treatment, and at a 1-month follow-up. Patients experienced a significant (P < 0.001) reduction in pain after treatment (mean ± SD: 1.3 ± 0.5) with a large effect size (d > 1). In addition, patients also experienced a significant increase in PPT immediate after the treatment (P < 0.05) and one month after discharge (P < 0.01), with effect sizes ranging from moderate (d = 0.4) to large (d > 1).A significant negative association (r_s = −0.525; P = 0.049) between the increase in PPT over the supraspinatus muscle and the decrease in pain was found: the greater the decrease in pain, the greater the increase in PPT. This case series has shown that manual treatment of active muscle TrPs can help to reduce shoulder pain and pressure sensitivity in shoulder impingement. Current findings suggest that active TrPs in the shoulder musculature may contribute directly to shoulder complaint and sensitization in patients with shoulder impingement syndrome, although future randomized controlled trials are required.     

Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: An application of muscle pain concepts to myofascial pain syndrome

This article discusses muscle pain concepts in the context of myofascial pain syndrome (MPS) and summarizes microdialysis studies that have surveyed the biochemical basis of this musculoskeletal pain condition. Though MPS is a common type of non-articular pain, its pathophysiology is only beginning to be understood due to its enormous complexity. MPS is characterized by the presence of myofascial trigger points (MTrPs), which are defined as hyperirritable nodules located within a taut band of skeletal muscle. MTrPs may be active (spontaneously painful and symptomatic) or latent (non-spontaneously painful). Painful MTrPs activate muscle nociceptors that, upon sustained noxious stimulation, initiate motor and sensory changes in the peripheral and central nervous systems. This process is called sensitization. In order to investigate the peripheral factors that influence the sensitization process, a microdialysis technique was developed to quantitatively measure the biochemical milieu of skeletal muscle. Biochemical differences were found between active and latent MTrPs, as well as in comparison with healthy muscle tissue. In this paper we relate the findings of elevated levels of sensitizing substances within painful muscle to the current theoretical framework of muscle pain and MTrP development.     

A comparison between different modes of real-time sonoelastography in visualizing myofascial trigger points in low back muscles

Objective: Currently, there is a lack of objective means to quantify myofascial trigger points (MTrPs) and their core features. Our research compares (1) MTrPs and surrounding myofascial tissue using two-dimensional grayscale ultrasound (2DGSUS) and vibration sonoelastography (VSE); (2) the accuracy of both modes in visualizing MTrPs; (3) ‘active’ and ‘latent’ MTrPs, using VSE; and (4) the accuracy of both modes in visualizing deep and superficially located MTrPs.

Methods: Fifty participants with more than two MTrPs in their quadratus lumborum, longissimus thoracis, piriformis, and gluteus medius muscles were assigned to an active MTrP (low back pain) group or a latent (currently pain free) MTrP group. MTrP identification was based on their essential criteria. An electronic algometer measured repeatedly the tenderness of MTrPs with reference to pressure pain threshold values. A handheld vibrator was applied over MTrPs, while VSE and 2DGSUS readings were taken using an EUB-7500 ultrasound scanner.

Results: There was a significant difference between MTrP strain and that of the immediately surrounding myofascial tissue, as measured using VSE (P?=?0·001). VSE visualized all superficial and deep MTrPs with an accuracy of 100% (for both groups); the blinded results obtained using 2DGSUS achieved 33% and 35% accuracy, respectively. There was no significant difference found between the tissue strain ratios of active and latent MTrPs (P?=?0·929).

Discussion: Sonoelastography can visualize superficial and deep MTrPs, and differentiate them from surrounding myofascial structure through tissue stiffness and echogenicity. VSE was more accurate than 2DGSUS in visualizing and imaging MTrPs.     

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.Key Words: Myofascial Pain Syndrome, Myofascial Trigger Points, Interrater Reliability, Palpation, Shoulder PainShoulder complaints are very common in modern industrial countries. Recent reviews^1–4 have indicated a one-year prevalence ranging from 4.7 to 46.7%. These reviews have also reported a lifetime prevalence between 6.7 and 66.7%. This wide variation in reported prevalence can be explained by the different definitions used for shoulder complaints and by differences in the age and other characteristics of the various study populations. Because making a specific structure-based diagnosis for patients with shoulder complaints is considered difficult due to the lack of reliable tests for shoulder examination, recent guidelines developed by the Dutch Society of General Practitioners have recommended instead using the term “shoulder complaints” as a working diagnosis⁵. Shoulder complaints have been defined in a similarly non-specific manner as signs and symptoms of pain in the deltoid and upper arm region, and stiffness and restricted movements of the shoulder, often accompanied by limitations in daily activities⁶.Despite the absence of reliable diagnostic tests to implicate these structures, the currently prevailing assumption is that in non-traumatic shoulder complaints, mostly the anatomical structures in the subacromial space are involved, i.e., the subacromial bursa, the rotator cuff tendons, and the tendon of the long head of the biceps muscle^7–9. However, this assumption does not take into account that muscle tissue itself can also give rise to pain in the shoulder region¹⁰. In our clinical experience, myofascial trigger points (MTrPs) may lead to myofascial pain in the shoulder and upper arm region and contribute to the burden of shoulder complaints.The term myofascial pain was first introduced by Travell¹⁰, who described it as “the complex of sensory, motor, and autonomic symptoms caused by myofascial trigger points.” An MTrP is a hyperirritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band. In addition, the spot is painful on compression and may produce characteristic referred pain, referred tenderness, motor dysfunction, and autonomic phenomena. Two different types of MTrPs have been described: active and latent. Active trigger points are associated with spontaneous complaints of pain. In contrast, latent trigger points do not cause spontaneous pain, but pain may be elicited with manual pressure or with needling of the trigger point. Despite not being spontaneously painful, latent MTrPs have been hypothesized to restrict range of motion¹¹ and to alter motor recruitment patterns¹².As noted above, referred pain is a key characteristic of myofascial pain. Referred pain is felt remote from the site of origin¹³. The area of referred pain may be discontinuous from the site of local pain or it can be segmentally related to the lesion, both of which may pose a serious problem for the correct diagnosis and subsequent appropriate treatment of muscle-related pain. The theoretical model for this phenomenon of referred pain was first proposed by Ruch¹⁴ and later modified by Mense^13–15 and Hoheisel¹⁴. Referred pain patterns originating in muscles have been documented using injection of hypertonic saline, electrical stimulation, or pressure on the most sensitive spot in the muscle^17–21. In the clinical setting, palpation is the only method capable of diagnosing myofascial pain. Therefore, reliable MTrP palpation is the necessary prerequisite for considering myofascial pain as a valid diagnosis²². Published interrater studies have reported poor to good reliability for MTrP palpation^23–29. However, only one study has included a muscle that could produce shoulder pain: Gerwin et al²⁷ reported a percent agreement (PA) of 83% for tenderness in the infraspinatus muscle (κ=0.48), 83% (κ=0.40) for the taut band, 59% (κ=0.17) for the local twitch response, and 89% (κ=0.84) for the referred pain.In light of this near absence of data, of the societal impact of shoulder complaints as noted above, and of the potential role of myofascial pain syndrome with regard to shoulder pain, the aim of this study was to determine the interrater reliability of MTrP palpation in three human shoulder muscles deemed by us to be clinically relevant, i.e., the infraspinatus, the anterior deltoid, and the biceps brachii muscles.     

The effect of manual pressure release on myofascial trigger points in the upper trapezius muscle

Sustained manual pressure has been advocated as effective treatment for myofascial trigger points (MTrPs). This study aimed to investigate the effect of manual pressure release (MPR) on the pressure sensitivity of latent MTrPs in the upper trapezius muscle using a novel pressure algometer. Subjects (N=37, mean age 23.1±3.2, M=12, F=23) were screened for the presence of latent MTrPs in the upper trapezius muscle (tender band that produced referred pain to the neck and/or head on manual pressure). Subjects were randomly allocated into either treatment (MPR) or control (sham myofascial release) groups. The pressure pain threshold (PPT) was recorded pre- and post-intervention using a digital algometer, consisting of a capacitance sensor attached to the tip of the palpating thumb. There was a significant increase in the mean PPT of MTrPs in the upper trapezius following MPR (P<0.001), but not following the sham treatment. Pressure was monitored and maintained during the application of MPR, and a reduction in perceived pain and significant increase in tolerance to treatment pressure (P<0.001) appeared to be caused by a change in tissue sensitivity, rather than an unintentional reduction of pressure by the examiner. The results suggest that MPR may be an effective therapy for MTrPs in the upper trapezius.     

Dry needling in chronic abdominal wall pain of uncertain origin

Background

Abdominal wall pain is considered as pain that arises from the abdominal muscles rather than the underlying viscera or the spine. It is frequently overlooked and is often misdiagnosed, as these patients continue to suffer with pain. Many such patients would have even been subjected to a psychiatric evaluation in view of the absence of any ostensible clinical cause for the pain. In this study, we describe the role of myofascial trigger points in the abdominal wall pain that could be a cause of chronic pain and present our findings of pain relief by dry needling technique.

Short-term effects of kinesio taping on trigger points in upper trapezius and gastrocnemius muscles

Background

Kinesio taping is a possible therapeutic modality for myofascial pain, nevertheless, very scarce research has been performed on this subject.

Pressure pain hypersensitivity and referred pain from muscle trigger points in elite male wheelchair basketball players

BackgroundShoulder injuries are common in individuals who use wheelchairs.ObjectivesThis study investigated the presence of mechanical pain hypersensitivity and trigger points in the neck-shoulder muscles in elite wheelchair basketball players with/without shoulder pain and asymptomatic able-bodied elite basketball players.MethodsEighteen male wheelchair basketball players with shoulder pain, 22 players without shoulder pain, and 20 able-bodied elite male basketball players were recruited. Pressure pain thresholds were assessed over C5-C6 zygapophyseal joint, deltoid muscle, and second metacarpal. Trigger points in the upper trapezius, supraspinatus, teres minor, infraspinatus, teres major, latissimus dorsi, subscapularis, pectoralis minor, pectoralis major and deltoid muscles were also examined.ResultsWheelchair basketball players with shoulder pain showed lower pressure pain thresholds over the C5-C6 joint and second metacarpal than elite wheelchair basketball players without pain (between-groups differences: 1.1, 95%CI 0.4, 1.8 and 1.8, 95%CI 0.8, 2.8, respectively) and able-bodied basketball players without pain (between-groups differences: 0.8, 95%CI 0.4, 1.2; 1.6, 95%CI 0.8, 2.4, respectively). The mean number of myofascial trigger points for wheelchair basketball players with unilateral shoulder pain was 4.8 ± 2.7 (2 ± 1 active, 2.9 ± 2.2 latent). Wheelchair basketball players and able-bodied basketball players without shoulder pain exhibited a similar number of latent trigger points (2.4 ± 2.0 and 2.4 ± 1.8, respectively). Wheelchair basketball players with shoulder pain exhibited higher number of active myofascial trigger points than those without pain (either with or without wheelchair), but all groups had a similar number of latent trigger points (P < 0.05).ConclusionsThe reported mechanical pain hypersensitivity suggests that active trigger points may play a role in the development of shoulder pain in elite male wheelchair basketball players.     

Stimulation of myofascial trigger points with ultrasound induces segmental antinociceptive effects: a randomized controlled study

Musculoskeletal pain affects a significant proportion of the general population. The myofascial trigger point is recognized as a key factor in the pathophysiology of musculoskeletal pain. Ultrasound is commonly employed in the treatment and management of soft tissue pain and, in this study, we set out to investigate the segmental antinociceptive effect of ultrasound. Subjects (n=50) with identifiable myofascial trigger points in the supraspinatus, infraspinatus and gluteus medius muscles were selected from an outpatient rehabilitation clinic and randomly assigned to test or control groups. Test subjects received a therapeutic dose of ultrasound to the right supraspinatus trigger point while control groups received a sham (null) exposure. Baseline pain pressure threshold (PPT) readings were recorded at the ipsilateral infraspinatus and gluteus medius trigger-point sites prior to ultrasound exposure. The infraspinatus point was chosen due to its segmental neurologic link with the supraspinatus point; the gluteus medius acted as a segmental control point. Following the ultrasound intervention, PPT readings were recorded at 1, 3, 5, 10 and 15 min intervals at both infraspinatus and gluteus medius trigger points; the difference between infraspinatus and gluteus medius PPT values, PPT seg, represents the segmental influence on the PPT. The ultrasound test group demonstrated statistically significant increases in PPT seg (decreased infraspinatus sensitivity) at 1, 3 and 5 min, when compared with PPT seg in the sham ultrasound group. These results establish that low-dose ultrasound evokes short-term segmental antinociceptive effects on trigger points which may have applications in the management of musculoskeletal pain.     

Effects of Deep Cervical Flexor Training on Pressure Pain Thresholds Over Myofascial Trigger Points in Patients With Chronic Neck Pain

Objective

The purpose of this study was to assess the effects of a low-load training program for the deep cervical flexors (DCFs) on pain, disability, and pressure pain threshold (PPT) over cervical myofascial trigger points (MTrPs) in patients with chronic neck pain.

Methods

Thirty patients with chronic idiopathic neck pain participated in a 6-week program of specific training for the DCF, which consisted of active craniocervical flexion performed twice per day (10-20 minutes) for the duration of the trial. Perceived pain and disability (Neck Disability Index, 0-50) and PPT over MTrPs of the upper trapezius, levator scapulae, and splenius capitis muscles were measured at the beginning and end of the training period.

Results

After completion of training, there was a significant reduction in Neck Disability Index values (before, 18.2 ± 12.1; after, 13.5 ± 10.6; P < .01). However, no significant changes in PPT were observed over the MTrPs.

Conclusion

Patients performing DCF training for 6 weeks demonstrated reductions in pain and disability but did not show changes in pressure pain sensitivity over MTrPs in the splenius capitis, levator scapulae, or upper trapezius muscles.