Intramuscular injections of botulinum toxin for the treatment of upper back myofascial pain syndrome: A systematic review of randomized controlled trials.

BACKGROUND AND OBJECTIVE: Myofascial pain syndrome (MPS) is a chronic musculoskeletal disorder characterized by the presence of trigger points. Among the treatment options, botulinum toxin injections have been investigated. The aim of this paper was to provide a synthesis of the evidence on intramuscular botulinum toxin injections for upper back MPS. DATABASES AND DATA TREATMENT: A systematic review of the literature was performed on the PubMed, Scopus and Cochrane Library, using the following formula: ("botulinum") AND ("musculoskeletal") AND ("upper back pain") OR ("myofascial pain"). RESULTS: Ten studies involving 651 patients were included. Patients in the control groups received placebo (saline solution) injections, anaesthetic injections + dry needling or anaesthetic injections. The analysis of the trials revealed modest methodological quality: one "Good quality" study, one "Fair" and the other "Poor". No major complications or serious adverse events were reported. Results provided conflicting evidence and did not demonstrate the superiority of botulinum toxin over comparators. Most of the included trials were characterized by a small sample size, weak power analysis, different clinical scores used and non-comparable follow-up periods. Even if there is no conclusive evidence, the favourable safety profile and the positive results of some secondary endpoints suggest a potentially beneficial action in pain control and quality of life. CONCLUSION: The currently available studies show conflicting results. Their overall low methodological quality does not allow for solid evidence of superiority over other comparison treatments. Further insights are needed to properly profile patients who could benefit more from this peculiar injective approach. SIGNIFICANCE: The randomized controlled trials included in this review compared using botulinum toxin to treat upper back MPS with placebo or active treatments (e.g., dry needling or anaesthetics) showing mixed results overall. Despite the lack of clear evidence of superiority, our study suggests that the use of botulinum toxin should not be discouraged. Its safety profile and encouraging results in pain control, motor recovery and disability reduction make it an interesting treatment, particularly in the subset of patients with moderate to severe chronic pain and active trigger points. To support the safety and efficacy of botulinum toxin, further high-quality studies are needed.

Role of Rehabilitation Exercise on Myofascial Pain Syndrome Causing Upper Back Pain.

Upper back pain is as painful or troublesome as the pain in the lower back or the neck. Myofascial pain syndrome which is most common cause of upper back pain is characterized by localized musculoskeletal pain and tenderness in association with trigger points. The aim of the study was to correlate the improvement of myofascial pain syndrome patients with proper and timely physical therapy. This quasi experimental study was conducted in the department of Physical Medicine and Rehabilitation, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh, from 1st January 2008 to 31st August 2008 to see the role of rehabilitation exercise on myofascial pain syndrome causing upper back pain. Sixty (60) patients of myofascial pain syndrome causing upper back pain were randomly assigned for treatment; out of which 23(38.33%) were male and 37(61.66%) were female. The male and female ratio was 1:1.6. The patients selected for the trial were divided into two groups: Group A and Group B. In group A (n=28) the patients were treated with thermotherapy- Microwave diathermy, non-steroidal anti inflammatory drugs and activities of daily living instructions and in Group B (n=32) with same interventions in addition to rehabilitation exercises. Treatment duration was 6 weeks. The difference of treatment improvement was statistically significant (p<0.05) from 1st week up to 6th week. After complete course of treatment 67.86% patients in Group A and 78.13% patients in group B reported improvement. So rehabilitation exercises can be a valuable adjunct to other modalities of treatment of myofascial pain syndrome causing upper back pain.

[Intervention effect of Qufeng Gutong Cataplasm on myofascial pain syndrome in rats and its mechanism].

This paper aims to investigate the intervention effect of Qufeng Gutong Cataplasm(QFGT) on myofascial pain syndrome(MPS) in rats and to preliminarily explain its mechanism from the perspective of improving muscle inflammation and pain. Male SD rats were divided into 6 groups, namely normal group, model group, positive control drug(Huoxue Zhitong Ointment, HXZT) group, and low, medium, and high-dose QFGT groups(75, 150, and 300 mg·d~(-1)). The rat model of MPS was established by striking combined with centrifugation for 8 weeks, during which QFGT and HXZT were used for corresponding intervention. Standard VonFrey fiber was used to evaluate the mechanical pain threshold, and acetone was used to detect the cold pain threshold. The electrophysiological activity of muscle at trigger point was detected, and the electromuscular analysis of trigger point was performed. CatWalk gait analyzer was used to detect pain-induced gait adaptation changes. The hematoxylin-eosin(HE) staining was used to observe the pathological changes in muscle and skin tissues at the trigger point of rats. Immunohistochemistry was used to detect the expression of capsaicin receptor transient receptor potential vanilloid 1(TRPV1) in muscle tissues and interleukin(IL)-33 in skin tissues at the trigger point. The protein expression levels of TRPV1, protein kinase B(Akt), phosphorylated protein kinase B(p-Akt), IL-1ß, and tumor necrosis factor-α(TNF-α) in muscle tissues at the trigger point were detected by Western blot. The results showed that as compared with the model group, the mechanical pain threshold and cold pain threshold of rats in other groups were increased after treatment with QFGT. The spontaneous electromyography(EMG) activity was observed in the model group, but QFGT alleviated the EMG activity in a dose-dependent manner. Gait analysis showed that standing duration, average intensity, swing speed, maximum contact point, maximum contact area, paw print length, paw print width, and paw print area were significantly improved in all QFGT groups. Pathological results showed that the disorder of muscle arrangement at the trigger point was decreased, muscle fiber adhesion and atrophy were reduced, and inflammatory cell infiltration was alleviated after treatment with QFGT. In addition, QFGT and HXZT both inhibited the protein expression of TRPV1, PI3K, Akt, p-Akt, IL-1ß, and TNF-α in the muscle tissues of rats with MPS. However, there was no significant difference in the pathological structure and expression of IL-33 in the treated skin as compared with the normal group. The related results have proved that QFGT can inhibit the release of inflammatory factors by inhibiting the TRPV1/PI3K/Akt signaling pathway in the muscle trigger point of rats with MPS and finally attenuate the atrophy and adhesion of local muscles and inflammatory infiltration, thereby relieving the muscle pain of rats with MPS, and local administration has no skin irritation.

Ultrasound-Guided Trigger Point Injections for the Treatment of Neck and Back Pain in the Emergency Department: A Randomized Trial.

OBJECTIVES: Patients frequently present to the emergency department (ED) with neck or back pain, which can be difficult to treat. We sought to compare ultrasound-guided trigger point injection (TPI) to standard medications for patients with neck or back pain. METHODS: We performed a single-center, open label, randomized controlled trial on ED patients with neck or back pain from myofascial pain syndrome comparing ultrasound-guided TPIs to those who received the combination of a nonsteroidal anti-inflammatory drug (NSAID) and a muscle relaxant (MR). The primary outcome of this study was the reduction in mean pain score at the time of ED disposition. RESULTS: In total, we analyzed 196 patients. At the time of ED disposition, patients in the TPI group had a mean reduction in their pain scores of 45.0 mm as compared to 49.9 mm in the NSAID plus MR group (difference: 4.9 [95% confidence interval (CI) -3.0 to 12.7], P = .22). At the first reassessment, patients in the TPI group had greater pain reduction by 10.7 mm (95% CI 3.1 to 18.4). The rate of rescue therapy use was higher in the NSAID plus MR group (difference: 17.5% [95% CI 4.4 to 36.2]). CONCLUSIONS: We found no difference in pain reduction at the time of ED disposition between patients randomized to the ultrasound-guided TPI group as compared to those who received an NSAID plus a MR. However, patients in the TPI group had greater pain reduction at the time of first reassessment and lower rates of rescue therapy use.

Ultrasound-guided rhomboid intercostal block for myofascial pain syndrome: a prospective clinical study.

BACKGROUND: Myofascial pain syndrome (MPS) is a common chronic pain syndrome that may affect quality of life, daily living activities, and psychological status. Ultrasound (US)-guided rhomboid intercostal block (RIB) is a recently defined plane block and used for chronic pain such as postmastectomy syndrome and MPS. Our aim was to evaluate the efficacy of US-guided RIB for the management of pain, quality of life, physical disability, and patient satisfaction in MPS. METHODS: In this prospective study, between February and March 2021, a total of 30 patients who applied with the diagnosis of MPS, were included. The patients received US-guided RIB. Pain intensity was evaluated using a numerical rating scale (NRS) at pretreatment, and just after the intervention, at day 1, and 1, 2, 4, and 6 weeks after the intervention. At pretreatment and 6 weeks after treatment, Short Form-36 Health Survey (SF-36) for health-related quality of life, Neck Disability Index (NDI), and patient satisfaction were evaluated. RESULTS: There was a statistically significant decrease in average NRS immediately after treatment, at day 1 and week 1,2,4, and 6 compared to the pretreatment (p < 0.0001). The average SF-36 scores advanced at 6 weeks after treatment. There was a statistically significant reduction in mean NDI scores throughout the follow-up period (p < 0.001). DISCUSSION: Our study demonstrated that RIB had improved neck function, physical and mental quality of life, and patient satisfaction in MPS. Therefore, we think US-guided RIB could be an alternative treatment modality in patients suffering from MPS.

Prevalence of Myofascial Pain Syndrome and Efficacy of Trigger Point Injection in Patients with Incurable Cancer: A Multicenter, Prospective Observational Study (MyCar Study).

OBJECTIVE: Myofascial pain syndrome (MPS) is caused by overload or disuse of skeletal muscles. Patients with cancer are often forced to restrict their movement or posture for several reasons. The study was conducted to investigate the prevalence and risks of MPS in patients with incurable cancer. The efficacy of trigger point injection (TPI) was also explored. METHODS: This was a multicenter, prospective observational study. Patients with incurable cancer who started receiving specialist palliative care were enrolled. We investigated the MPS in this population and accompanying risk factors for restricting body movement. Pre- and post-TPI pain was also evaluated using a Numerical Rating Scale (NRS) in patients who received TPI. The primary outcome was the prevalence of MPS. RESULTS: A total of 101 patients were enrolled from five institutions in Japan. Most of the patients (n = 94, 93.1%) had distant metastases, and half of the patients (50, 49.5%) received anticancer treatment. Thirty-nine (38.6%) patients had MPS lesions at 83 sites. Multivariate analysis revealed that the significant risk factor for MPS was poor Performance Status (PS) (odds ratio 3.26; 95% confidence interval [CI] 1.18-9.02, P = .023). We performed TPI for 40 out of 83 MPS lesions. Mean NRS for MPS before TPI was 7.95, which improved to 4.30 after TPI (P < .001). CONCLUSIONS: MPS was common in patients with incurable cancer and the risk factor identified in this study was poor performance status. TPI could be a treatment option.

Combining Ozonated Autohemotherapy with Pharmacological Therapy for Comorbid Insomnia and Myofascial Pain Syndrome: A Prospective Randomized Controlled Study.

Objective: To examine the efficacy and safety of ozonated autohemotherapy (O3-AHT) combined with pharmacological therapy for comorbid insomnia and myofascial pain syndrome (MPS). Materials and Methods: One hundred and eighteen patients were randomly divided into two groups: the control group (N = 50) and the O3-AHT group (N = 53). Patients in both groups were given the same pharmacological management for three weeks. Patients in the O3-AHT group were treated with ozonated autohemotherapy (the concentration of ozone was 20 µg/ml in the first week, 30 µg/ml in the second week, and 40 µg/ml in the third week) combined with pharmacological therapy. Primary (the insomnia severity index (ISI) and visual analogue scale (VAS)) and secondary outcomes (the Epworth sleepiness scale (ESS), polysomnography data, the anxiety and preoccupation about sleep questionnaire (APSQ), the beck depression index (BDI), and the multidimensional fatigue inventory (MFI)) were examined at pretreatment, posttreatment, 1 month, and 6 months. Results: Fifty patients in the control group and fifty-three patients in the O3-AHT group completed the study. In both groups, insomnia and pain symptoms were relieved significantly compared with pretreatment. Compared with the control group, the O3-AHT group had significantly improved sleep quality, pain, and negative mood at different time points. No adverse complications were observed in either group. Conclusion: Compared with pharmacological therapy alone, ozonated autohemotherapy combined with pharmacological therapy can ameliorate insomnia, reduce pain intensity, improve negative mood, and alleviate fatigue more effectively without serious adverse complications.

Effectiveness of pregabalin treatment for trigger points in patients with comorbid myofascial pain syndrome and fibromyalgia syndrome: a randomized controlled trial.

AIM OF THE STUDY: Myofascial pain syndrome (MPS) is a common problem in the general population. MPS should not be a local/peripheral painful syndrome and considered to be a syndrome of central sensitivity. We aimed to investigate the effect of pregabalin in patients with MPS in this study. MATERIALS AND METHODS: We randomized 40 patients into two groups, and 17 patients per group completed the study. Female patients in group I received pregabalin and exercise therapy, whereas those in group II received exercise therapy alone. All patients were evaluated as follows: for pain by visual analog scale (VAS); trigger-point pressure pain threshold-(PPT) by algometry; neuropathic pain using the Douleur Neuropathique en 4 Questions (DN4) and quality of life with the Short Form-36 (SF36). Evaluations were performed pre-treatment and at the end of the first and third months of treatment. Clinical trial ID: NCT04600037, retrospectively registered 20/10/2020. RESULTS: In group I, significant improvements were observed in VAS, trigger-point-PPT, physical component summary-SF-36, at the first and third months. In group II, statistically significant improvements were observed in VAS, trigger-point-PPT after the first and third months. Group I showed statistically better improvements in VAS, trigger points-PPT, physical component summary-SF36 compared with group II by the third month. CONCLUSION: Pregabalin treatment is effective for controlling trigger points. Pregabalin treatment is also more effective than exercise treatment at improving quality of life in patients with MPS.

Trigger point injections for axial back pain in adolescents.

Adolescents who participate in athletics or have abnormal musculoskeletal anatomy have higher incidences of back pain than non-athletic peers with normal anatomy. Significant time and money spent in diagnostic evaluations for axial back pain can result in treatment delay causing a subsequent decrease in quality of life. Myofascial trigger points are a commonly overlooked reason for axial back pain. They develop due to an abnormal myoneural connection in the setting of muscle overuse. Trigger point injections are a technically simple intervention that is both diagnostic and therapeutic in alleviating trigger point-mediated back pain. There are few complications from these injections, and they should be considered prior to surgical referral or fluoroscopic-guided interventions.

Granisetron vs. lidocaine injection to trigger points in the management of myofascial pain syndrome: a double-blind randomized clinical trial.

OBJECTIVES: Granisetron and lidocaine injections have been used for the management of myofascial pain syndrome. This study was aimed to compare the efficacy of granisetron and lidocaine injections to trigger points of upper trapezius in the management of myofascial pain syndrome. METHODS: We performed a double-blind randomized clinical trial in an outpatient clinic of physical medicine and rehabilitation at a teaching hospital. A total of 40 patients aged ≥18 with neck pain due to myofascial pain syndrome were included. They had pain for at least one month with the intensity of at least 30 mm on a 100 mm visual analog scale. Each participant received a single dose of 1 mL lidocaine 2% or 1 mg (in 1 mL) granisetron. The solutions were injected into a maximum of three trigger points of the upper trapezius. We instructed all patients to remain active while avoiding strenuous activity for three or four days, and to perform stretch exercise and massage of their upper trapezius muscles. We assessed the patients before the interventions, and one month and three months post-injection. The primary outcome was the Neck Disability Index and the secondary outcome was the Neck Pain and Disability Scale. RESULTS: Both interventions were successful in reducing neck pain and disability (all p-values <0.001). However, the neck pain and disability responded more favorably to lidocaine than granisetron (p=0.001 for Neck Disability Index, and p=0.006 for Neck Pain and Disability Scale). No significant side-effect was recognized for both groups. CONCLUSIONS: Both lidocaine and granisetron injections to trigger points are effective and safe for the management of the syndrome and the benefits remain at least for three months. However, lidocaine is more effective in reducing pain and disability. The injections are well-tolerated, although a transient pain at the site of injections is a common complaint. One mL of lidocaine 2% is more effective than 1 mg (in 1 mL) granisetron for injecting into the trigger points of the upper trapezius in myofascial pain syndrome.

Effectiveness of Botulinum Toxin for Treatment of Symptomatic Pelvic Floor Myofascial Pain in Women: A Systematic Review and Meta-analysis.

OBJECTIVES: The aims of the study were to systematically review the literature and to synthesize the evidence for the effectiveness of botulinum toxin injection to the pelvic floor muscles for treating pelvic floor myofascial pain in female patients. METHODS: This systematic literature search was performed in February 2018 and updated in September 2019. Articles were screened based on predefined criteria: (1) adult population, (2) female patients, (3) treatment of pelvic pain by transvaginal botulinum toxin injection into the pelvic floor, (4) published in English or English translation available, (5) study design including randomized controlled trials, cohort studies, and case series with more than 10 participants, and (6) quantitative report of pain scores. Nine studies were included in the primary analysis, and an unpublished study was included in a sensitivity analysis. A random effects model with robust variance estimation was used to estimate the pooled mean difference in patient-reported pain scores after botulinum toxin injection. RESULTS: A statistically significant reduction in patient-reported pain scores was noted at 6 weeks after botulinum toxin injection (mean difference, 20.3; 95% confidence interval, 11.7-28.9) and continued past 12 weeks (mean difference, 19.4; 95% confidence interval, 14.6-24.2). Significant improvement was noted in secondary outcomes including dyspareunia, dyschezia, and quality of life. CONCLUSIONS: This systematic review and meta-analysis support the conduct of future, large-scale randomized controlled trials to determine the efficacy and optimize administration of botulinum toxin injections for treatment of pelvic floor myofascial pain and associated symptoms in women.

Comparison of the Efficacy of Botulinum Toxin, Local Anesthesia, and Platelet-Rich Plasma Injections in Patients With Myofascial Trigger Points in the Masseter Muscle.

PURPOSE: Masticatory myofascial trigger points (TrP) are one of the major causes of nondental pain in the orofacial region. Intramuscular injections are considered the first-line treatment for myofascial TrPs. The objectives of this study were to evaluate and compare the effectiveness of local anesthesia (LA), botulinum toxin (BTX), and platelet-rich plasma (PRP) injections for the treatment of myofascial TrPs in the masseter muscle. METHODS: In this retrospective study, the sample was composed of patients with myofascial TrPs in masseter muscle who were treated between 2016 and 2019. Patients were divided into 3 groups according to treatment methods: group I (LA injection), group II (BTX injection), and group III (PRP injection). Primary outcome variable was the average pain level at rest and while chewing, and pressure pain intensity (PPI), Jaw Functional Limitation Scale (JFLS) value, and quality-of-life (measured using Oral Health Impact Profile-14 (OHIP-14)) were secondary outcomes. The outcome variables were assessed at diagnosis, and 1, 3, and 6 months post-treatment. RESULTS: The study consisted of 82 patients (group I, 27; group II, 26; group III, 29). At 1 and 3 months, improvement in all parameters was recorded in all groups. Groups I and II showed superior improvement in all parameters compared with group III at 3 months. Improvements in VAS pain, JFLS, and OHIP-14 values were significantly better in group II than group I at 3 months (P = .009; P = .004; P = .002). At 6 months, significant improvement in VAS pain, JFLS, and OHIP-14 (P = .008; P < .001; P < .01) values was recorded only in group II. CONCLUSIONS: All procedures successfully improved the symptoms of TrPs in the masseter muscle at 1 and 3 months. However, BTX injection seemed superior at the 3-month follow-up and remained effective up to 6 months.

Botulinum toxin type A and acupuncture for masticatory myofascial pain: a randomized clinical trial

Abstract BoNT-A has been widely used for TMD therapy. However, the potential benefits compared to dry needling techniques are not clear. Objective this study aimed to compare the immediate effects of botulinum toxin type A (BoNT-A) injections and Acupuncture in myofascial temporomandibular disorders (TMD) patients. Methodology 54 women were divided into three groups (n=18). AC patients received four sessions of traditional acupuncture, being one session/week during 20-min. BoNT-A patients were bilaterally injected with 30U and 10U in masseter and anterior temporal muscles, respectively. Moreover, a control group received saline solution (SS) in the same muscles. Self-perceived pain was assessed by visual analog scale, while pressure pain threshold (PPT) was verified by a digital algometer. Electromyographic evaluations (EMG) of anterior temporal and masseter muscles were also measured. All variables were assessed before and 1-month after therapies. The mixed-design two-way repeated measures ANOVA and Tukey's post-hoc tests were used for analysis, considering a=0.05. Results Self-perceived pain decreased in all groups after one month of therapy (P<.001). BoNT-A was not better than AC in pain reduction (P=0.05), but both therapies were more effective in reducing pain than SS (P<0.05). BoNT-A was the only treatment able to improve PPT values (P<0.05); however, a severe decrease of EMG activity was also found in this group, which is considered an adverse effect. Conclusion after one month of follow-up, all therapies reduced the self-perceived pain in myofascial TMD patients, but only BoNT-A enhanced PPT yet decreased EMG.

The effect of the twin block compared with trigger point injections in patients with masticatory myofascial pain: a pilot study.

OBJECTIVE: The twin block, a novel nerve block that blocks the deep temporal and masseteric branches of the trigeminal nerve, has been shown to be effective in the short-term management of masticatory myofascial pain. However, little is known about its effectiveness in long-term management. The objective of this study was to assess the efficacy of the twin block in comparison with trigger point injections for the treatment of masticatory myofascial pain. STUDY DESIGN: Forty-eight patients age 18 to 89 years were randomly assigned to the twin block group (n = 23) or the trigger point injection group (n = 25). The final analysis was based on a total number of 40 patients. RESULTS: Mean numerical pain intensity at baseline was 6.54 ± 1.90 for the trigger point injection group and 6.47 ± 2.23 for the twin block group. At the 6th month visit, it was 1.85 ± 1.85 for the trigger point injection group and 1.85 ± 1.94 for the twin block group. There were no statistically significant differences in pain intensity between the 2 groups at baseline (P = .64) and at the 6th month follow-up (P = .45). CONCLUSIONS: The twin block is effective in the long-term management of masticatory myofascial pain compared with trigger point injections. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03870191.

Capsaicin topical cream (8%) for the treatment of myofascial pain syndrome / Creme tópico de capsaicina (8%) para o tratamento da síndrome da dor miofascial

Abstract Background: Myofascial pain syndrome is a common cause of musculoskeletal pain. The objective of this study was to evaluate the potential analgesic action of 8% capsaicin cream for topical use in patients with myofascial pain syndrome. Methods: Initially, cream formulations of PLA (Placebo) and CPS (Capsaicin 8%) were developed and approved according to the current requirements of the health authority agency. The 40 participating patients were randomly assigned to the PLA and CPS groups in a double-blind fashion. Before the creams were topically administered, according to the allocation group, the local anesthetic was used for a period of 50 minutes directly in the area of interest. The cream was applied to the area of the skin over the trigger point, represented by the area with pain at palpation, in an amount of 10 g for 30 minutes in a circular area of 24 mm diameter. Subsequently, the cream was removed and the skin tolerability parameters were evaluated. The pain was measured before and during the formulation application, as well as at 1 hour, 7 days, 30 days, and 60 days after the procedure, evaluated using a verbal numerical scale (from 0 to 10: with 0 = no pain and 10 = worst pain imaginable). Results: No patient in PLA Group had hyperemia or burning sensation at the site of application, while 85% of patients in CPS Group had hyperemia or burning sensation at 15 minutes. These complaints disappeared 24 hours after the cream was removed. The pain score in CPS Group decreased steadily up to the 60th day of evaluation (p < 0.0001). Conclusion: Application of the formulations did not cause macroscopic acute or chronic skin lesions in patients, and the 8% capsaicin formulation was beneficial and well tolerated.

Resumo Justificativa: A síndrome da dor miofascial é uma causa comum de dor musculoesquelética. O objetivo deste estudo foi avaliar a potencial ação analgésica de 8% do creme de capsaicina para uso tópico em pacientes com síndrome da dor miofascial. Métodos: Inicialmente, as formulações de creme de PLA (Placebo) e CPS (Capsaicina 8%) foram desenvolvidas e aprovadas de acordo com os requisitos atuais da agência de autoridade de saúde. Os 40 pacientes participantes foram distribuídos aleatoriamente e de forma duplo-cega para os grupos PLA e CPS. Antes dos cremes serem administrados topicamente, de acordo com o grupo de alocação, o anestésico local foi usado por um período de 50 minutos diretamente na área de interesse. A administração ocorreu na área da pele sobre o ponto-gatilho, o qual apresentou a área dolorida à palpação, em uma quantidade de 10 g por 30 minutos em área circular com diâmetro de 24 mm. Posteriormente, o creme foi removido e os parâmetros de tolerabilidade à pele foram avaliados. A dor foi medida antes e durante a aplicação da formulação, bem como 1 hora, 7 dias, 30 dias e 60 dias após o procedimento avaliado pela escala numérica verbal (0 a 10, com zero sem dor e dez a pior dor imaginável). Resultados: Nenhum paciente no grupo PLA experimentou hiperemia ou sensação de queimação no local de aplicação do creme, enquanto 85% dos que experimentaram no grupo CPS apresentaram hiperemia ou sensação de queimação 15 minutos. Essas queixas desapareceram 24 horas após a remoção do creme. O escore de dor no grupo CPS diminui de forma sustentada até o 60° dia de avaliação (p < 0,0001). Conclusão: A administração das formulações não causou lesões cutâneas agudas ou crônicas macroscópicas nos pacientes e a formulação de 8% de capsaicina foi benéfica e bem tolerada.

Comparison of the Efficacies of Dry Needling and Botox Methods in the Treatment of Myofascial Pain Syndrome Affecting the Temporomandibular Joint.

BACKGROUND: To compare the efficacies of botulinum toxin-A injection and dry needling methods in the treatment of patients with myofascial pain syndrome (MPS) in the temporomandibular joint (TMJ). METHODS: In this prospective study, 40 MPS patients (29 women, 11 men) were randomly assigned to abobotulinum toxin-A injection (Group 1, n = 20) or dry needling (Group 2, n = 20) groups. Pain, crepitation, functional limitation, maximum mouth opening, jaw strength were evaluated at baseline and 6 weeks, and the results in both groups were compared. RESULTS: The average age of the authors' patients was 33.8±8.1. There was a remarkable difference between 2 groups regarding visual analog scale for TMJ pain at rest (P = 0.048). The pain at rest was relieved more effectively in Group 2 at the end of 6 weeks. Improvement in jaw protrusion angles on the right (P = 0.009) and left (P = 0.002) sides was more evident in Group 2 after 6 weeks. There were significant pain relief and functional improvement after treatment in both groups. In Group 2, recovery of the TMJ function was more obvious in 6 weeks following dry needling (P = 0.002). CONCLUSION: The authors suggest that abobotulinum toxin-A injection and dry needling yield satisfactory therapeutic outcomes regarding pain relief and restoration of function in patients with MPS involving TMJ. Further multicentric, randomized, controlled trials on larger series are warranted to obtain more accurate and reliable information.

Cannabidiol, cannabinol and their combinations act as peripheral analgesics in a rat model of myofascial pain.

OBJECTIVE: This study investigated whether local intramuscular injection of non-psychoactive cannabinoids, cannabidiol (CBD), cannabinol (CBN), cannabichromene (CBC) and their combinations can decrease nerve growth factor (NGF)-induced masticatory muscle sensitization in female rats. DESIGN: In awake rats, changes in mechanical sensitivity induced by intramuscular injection of NGF and cannabinoids were measured by applying an electronic von Frey hair over the masseter muscle to measure the withdrawal response. The effect of CBD (5 mg/ml) and CBN (1 mg/ml) or their combinations CBD/CBN (1:1 mg/ml or 5:1 mg/ml) were assessed. To confirm a peripheral action, electrophysiological experiments were undertaken in anesthetized rats to examine whether intramuscular injections of CBD (5 mg/ml) and CBN (1 mg/ml) altered the mechanical threshold of masticatory muscle mechanoreceptors. RESULTS: In behavioral experiments, CBD (5 mg/ml) or CBN (1 mg/ml) decreased NGF-induced mechanical sensitization. Combinations of CBD/CBN induced a longer-lasting reduction of mechanical sensitization than either compound alone. No significant change in mechanical withdrawal threshold was observed in the contralateral masseter muscles and no impairment of motor function was found with the inverted screen test after any of the treatments. Consistent with behavioral results, CBD (5 mg/ml), CBN (1 mg/ml) and the combination of CBD/CBN (1:1 mg/ml) increased the mechanical threshold of masseter muscle mechanoreceptors. However, combining CBD/CBN (5:1 mg/ml) at a higher ratio reduced the duration of this effect. This may indicate an inhibitory effect of higher concentrations of CBD on CBN. CONCLUSIONS: These results suggest that peripheral application of these non-psychoactive cannabinoids may provide analgesic relief for chronic muscle pain disorders such as temporomandibular disorders and fibromyalgia without central side effects.

The myofascial component of the pain in the painful shoulder of the hemiplegic patient

OBJECTIVES: Poststroke shoulder pain occurs very frequently and compromises function and quality of life. Because treatment depends on a multidisciplinary approach, it is desirable to optimize effectiveness. Myofascial pain syndrome is defined by the presence of trigger points that can also be found in spastic stroke patients. The aim of this study was to evaluate the frequency of myofascial pain in the shoulder girdle muscles in patients with poststroke shoulder pain and to document the clinical and functional results obtained with specific treatment for this condition. METHODS: Spastic stroke hemiplegic patients undergoing rehabilitation at the Rehabilitation Center of the Hospital das Clínicas of the Ribeirão Preto Medical School of the University of São Paulo were evaluated regarding the intensity and characteristics of shoulder pain, previous therapeutic interventions, shoulder goniometry and the presence of trigger points. Patients underwent trigger point blockade by intramuscular infiltration of 1% lidocaine. The evaluation and treatment procedures were repeated in the subsequent 3 weeks as long as the pain intensity was greater than 5 on a visual analog scale (VAS). In the fourth week, the evaluation procedures were repeated. Patients who were in a multiprofessional rehabilitation program were instructed to continue the treatment, and the others received complementary therapeutic advice if necessary to initiate it. The evaluations were performed at 0, 1, and 3 weeks and after 4 months. RESULTS: Twenty-one patients (13 men; age=67.8±10.2 years; right hemiparesis: 11) participated in the study, and there was a reduction in pain assessed by VAS from baseline (7.6±2.7) to the first week (5.8±3.6; p<0.05) through the end of the third week (5.2±3.5; p<0.05), but not at the end of four months (6.6±2.9; p=0.11). Good responders had significantly lower pain levels after the third week and presented with a larger range of motion for passive abduction by the end of 4 months. These results demonstrate that the myofascial component of pain should be considered in poststroke shoulder pain and that its treatment may be a pathway for the rapid and long-lasting relief of symptoms. CONCLUSION: Trigger point blockade with lidocaine can reduce pain perception in spastic hemiplegic shoulder in as much as 50% of stroke survivors for four months.

The Use of Botulinum Toxin for the Treatment of Myofascial Pain in the Masticatory Muscles.

Although the use of botulinum toxin has been recommended for the management of myofascial pain and dysfunction, the precise mechanism of its action remains undetermined and studies on its effectiveness are equivocal. Moreover, even if such treatment may temporarily relieve the symptoms, it does not address the cause of the problem. Also, its use is not free of potential complications. On this basis, botulinum toxin does not seem to be a logical treatment of myofascial pain and dysfunction.

[Therapy of myofascial pain syndrome face with thioctic acid]. / Terapiia miofastsial'nogo bolevogo sindroma litsa preparatami tioktovoi kisloty.

Authors present a case-report of a 36-year-old patient with pain syndrome in the face region (craniomandibular dysfunction with occlusive disorders) involving pericranial muscles and shoulder girdle muscles. Thioctic acid was prescribed as a basic therapy, and relaxation tire, mimic gymnastics, post-isometric relaxation, vitamin and mineral complex were additionally used. Thioctic acid was prescribed according to the following scheme: stage I - intravenous injections of thioctic acid (600 mg/daily, 5 procedures, every other day); stage II - oral administration of the drug in the dose of 600 mg/daily for 3 months. A significant reduction of pain syndrome and the palpable tension of muscles were noted; the symmetric even muscle tone was revealed. This case-report demonstrates the high efficacy of thioctic acid in treatment of patients with craniomandibular disorders using the 2-stage scheme. There was a significant improvement of quality of life of the patients due to the additional use of vitamin and mineral complex and medical tools (relaxation tire) for treatment at all stages of pain formation.