Central Sensitization Is Modulated Following Trigger Point Anesthetization in Patients with Chronic Pain from Whiplash Trauma. A Double-Blind, Placebo-Controlled, Crossover Study

Respiratory dysfunction in whiplash associated disorders (WAD) with cervical plexus syndrome - A case report

Whiplash Associated Disorders (WAD) represents a chronic post-traumatic pain syndrome from indirect flexion-extension trauma to the neck. The condition exhibits significant variability among affected individuals and can involve numerous secondary symptoms, including but not limited to myalgia, central sensitization, migraines, photophobia, jaw pain, dysphagia, joint stiffness, and tinnitus, while significant breathing problems are not commonly associated with or prominently considered in WAD. Herein, we present the diagnosis and successful surgical treatment of severe respiratory dysfunction and staccato speech in a patient with WAD, who over a period of more than ten years underwent multiple spirometry evaluations for breathing difficulties that correlated with the severity of neck pain. In 2019, his condition deteriorated, with significantly increased pain and dyspnea leading to further evaluations that included laboratory studies and consultations with specialists in neurosurgery, neurology, pulmonology, neurophysiology, ENT, general internal medicine, cardiology, radiology, speech pathology, physical medicine, orthopedic surgery, and hand surgery at three separate academic centers in Norway. Eventually, the patient was diagnosed with a condition that is regularly observed among patients referred to our office for evaluation and surgical treatment of chronic, whiplash related pain, and that we propose to label Cervical Plexus Syndrome. One year following exploration and neurolysis of sensory nerves to the right and left superficial cervical plexus, the patient remains pain free, with unimpeded speech and breathing as demonstrated by postoperative spirometry and video recordings. Although the underlying pathophysiology remains unclear, we report what we believe to be the first successful surgical treatment of serious respiratory dysfunction from pain generators in tissue that historically is considered anatomically and functionally separate from the mechanics of breathing. Further investigation will be needed to determine prevalence of respiratory dysfunction in chronic neck pain.

Trigger Point Therapy Techniques as an Effective Unconventional Method of Treating Tension Headaches: A Systematic Review

Background/Objectives The main aim of the literature review was to determine whether different trigger point therapy techniques are effective in decreasing the intensity, frequency, and duration of tension-type headaches. An additional aim was to assess the impact of trigger point therapy on other physical and psychological variables in tension-type headaches. Methods This literature review was conducted in accordance with PRISMA guidelines, and the inclusion and exclusion criteria were developed using the PICO(s) strategy. Searches were carried out in four databases: PubMed, Science Direct, Cochrane Library, and PEDro. Results Of the 9 included studies with 370 participants, 6 studies were randomised controlled trials, 2 were pilot studies, and 1 was a case report. Conclusions Trigger point therapy has reduced the duration, intensity, and frequency of headaches. Dry needling, ischaemic compression, Positional Relaxation Techniques, and massage protocols focused on deactivating trigger points are effective methods of unconventional treatment of tension-type headaches.

The effect of myofascial release of the physiological chains on the pain and health status in patients with fibromyalgia, compared to passive muscle stretching and a control group: a randomized controlled clinical trial

OBJECTIVE

To explore the potential effectiveness of myofascial release compared to passive muscle stretching and to a control group in modulating pain intensity and health status in adults diagnosed with fibromyalgia (FM).

MATERIALS AND METHODS

A preliminary randomized controlled clinical trial was conducted, consisting of eight weekly sessions. The participants were divided into three groups: myofascial release group (RG = 13), a muscle stretching group (SG = 13), and a control group (CG = 12), which received advice from a rheumatologist. The outcomes measured were the visual analogue pain scale (VAS), the fibromyalgia impact questionnaire (FIQ) (representing health status), and the number of painful areas. Univariate analyzes of covariance (ANCOVA) were performed at baseline, after 4 weeks (during treatment), after 8 weeks (post-treatment), and after 12 weeks (follow-up). The International Physical Activity Questionnaire (IPAQ), the Beck Depression Inventory (BDI) and the Pain Catastrophizing Scale (PCS) were included as covariates. Clinical trial registration number: NCT: 03408496.

RESULTS

After eight weeks, the RG showed lower VAS scores compared to the CG (mean difference 95% CI: -5.10 to -1.26) and the SG (mean difference 95% CI: -4.9 to -0.23) with no difference between the SG and the CG. The total FIQ score for the RG was lower than the CG after 4 weeks (95% CI: -49.92 to -5.61), and 8 weeks (mean difference 95% CI: -52.72 to -15.73), although there was no difference between the RG and SG, as well as between the SG and CG, at both time points. The number of painful body areas was similar in all groups at the four time points.

CONCLUSION

Preliminary results suggest that the RG possibly showed greater improvements in pain intensity and health status compared to the CG, and possibly greater improvements in pain intensity compared to the SG.

Buccal acupuncture combined with ultrasound-guided dry needle-evoked inactivation of trigger points to treat cervical and shoulder girdle myofascial pain syndrome

BACKGROUND

Myofascial pain syndrome (MPS) is a common disease with easy persistence and recurrence. In clinical practice, although many methods have been adopted to prevent and treat MPS, the control of MPS is still not satisfactory.

OBJECTIVE

To compare the safety and effectiveness of buccal acupuncture, inactivation of trigger points (MTrPs), and their combination in the treatment of MPS.

METHODS

Two hundred MPS patients in the pain clinic were randomly divided into four groups (n= 50) to receive oral drugs (Group A), oral drugs + buccal needle (Group B), oral drugs + MTrP inactivation (Group C), or oral drugs + buccal needle + MTrP inactivation (Group D).

RESULTS

The visual analogue scale (VAS) and cervical range of motion (ROM) of Group D were significantly lower than those of the other three groups, and the pressure pain threshold (PPT) value of labelled MTrPs was significantly higher than those of the other three groups (P< 0.05). The excellent rate and total effective rate of Group D were significantly higher than those of the other three groups. Group C had the highest pain score and the lowest acceptance score. The results showed that buccal acupuncture combined with ultrasound-guided dry needle-evoked inactivation of MTrPs can significantly reduce the VAS score of MPS patients, improve the range of motion of the cervical spine, and improve patient satisfaction.

CONCLUSIONS

This study provides a highly accepted and satisfactory treatment for MPS, which is worthy of clinical promotion.

Cervical musculoskeletal impairments in the 4 phases of the migraine cycle in episodic migraine patients

OBJECTIVE

To assess cervical musculoskeletal impairments during the 4 phases of a migraine cycle in episodic migraine patients, controlling for the presence of concomitant neck pain.

METHODS

Differences in cervical musculoskeletal impairments were assessed during the 4 migraine phases in episodic migraine patients and compared with healthy controls controlling for concomitant neck pain. Cervical musculoskeletal impairments were assessed as follow: cervical active range of motion; flexion rotation test; craniocervical flexion test and calculation of activation pressure score; the total number of myofascial trigger points in head/neck muscles; the number of positivevertebral segments (headache's reproduction) during passive accessory intervertebral movement; pressure pain thresholds over C1, C2, C4, C6 vertebral segments bilaterally, trigeminal area, hand, and leg. Signs of pain sensitization were assessed by evaluating mechanical pain threshold over trigeminal area and hand, pressure pain thresholds, and the wind-up ratio. The Bonferroni-corrected p-value (05/4 = 0.013) was adopted to assess the difference between groups, while a p-value of 0.05 was considered significant for the correlation analysis.

RESULTS

A total of 159 patients and 52 controls were included. Flexion rotation test and craniocervical flexion test were reduced in all 4 phases of the migraine cycle versus healthy controls (p < 0.001). The number of myofascial trigger points and positive vertebral segments was increased in all 4 phases of the migraine cycle versus healthy controls (p < 0.001). Flexion, extension, and total cervical active range of motion and cervical pressure pain thresholds were reduced in episodic migraine in the ictal phase versus controls (p < 0.007) with no other significant differences. Outside the ictal phase, the total cervical active range of motion was positively correlated with trigeminal and leg pressure pain threshold (p < 0.026), the number of active myofascial trigger points and positive positive vertebral segments were positively correlated with higher headache frequency (p=0.045), longer headache duration (p < 0.008), and with headache-related disability (p = 0.031). Cervical pressure pain thresholds were positively correlated with trigeminal, hand, and leg pressure pain threshold (p < 0.001), and trigeminal and leg mechanical pain thresholds (p < 0.005), and negatively correlated with the wind-up ratio (p < 0.004).

CONCLUSION

In all phases of the migraine cycle, independent of the presence of concomitant neck pain, episodic migraine patients showed reduced flexion rotation test and craniocervical flexion test and an increased number of myofascial trigger points and passive accessory vertebral segments. These impairments are correlated with enhanced headache duration, headache-related disability, and signs of widespread pain sensitization. Reduction in active cervical movement and increased mechanical hyperalgesia of the cervical was consistent in ictal episodic migraine patients and the subgroups of episodic migraine patients with more pronounced widespread sensitization.

Advanced magnetic resonance imaging of chronic whiplash patients: a clinical practice-based feasibility study

BACKGROUND

Whiplash injury is common following road traffic crashes affecting millions worldwide, with up to 50% of the injured developing chronic symptoms and 15% having a reduced working capability due to ongoing disability. Many of these patients receive treatment in primary care settings based upon clinical and diagnostic imaging findings. Despite the identification of different types of injuries in the whiplash patients, clinically significant relationships between injuries and chronic symptoms remains to be fully established. This study investigated the feasibility of magnetic resonance imaging (MRI) techniques including quantitative diffusion weighted imaging and measurements of cerebrospinal fluid (CSF) flow as novel non-invasive biomarkers in a population of healthy volunteers and chronic whiplash patients recruited from a chiropractic clinic for the purpose of improving our understanding of whiplash injury.

METHODS

Twenty chronic whiplash patients and 18 healthy age- and gender matched control subjects were included [mean age ± SD (sex ratio; females/males), case group: 37.8 years ± 9.1 (1.22), control group: 35.1 years ± 9.2 (1.25)]. Data was collected from May 2019 to July 2020. Data from questionnaires pertaining to the car crash, acute and current symptoms were retrieved and findings from clinical examination and MRI including morphologic, diffusion weighted and phase-contrast images were recorded. The apparent diffusion coefficient and fractional anisotropy were calculated, and measurement and analysis of CSF flow was conducted. Statistical analyses included Fisher's exact test, Mann Whitney U test and analysis of variance between groups.

RESULTS

The studied population was described in detail using readily available clinical tools. No statistically significant differences were found between the groups on MRI.

CONCLUSIONS

This study did not show that MRI-based measures of morphology, spinal cord and nerve root diffusion or cerebrospinal fluid flow are sensitive biomarkers to distinguish between chronic whiplash patients and healthy controls. The detailed description of the chronic whiplash patients using readily available clinical tools may be of great relevance to the clinician. In the context of feasibility, clinical practice-based advanced imaging studies with a technical setup similar to the presented can be expected to have a high likelihood of successful completion.

Can Central Sensitization after injury persist as an autonomous pain generator? - A comprehensive search for evidence

OBJECTIVE

To conduct a comprehensive search for evidence whether Central Sensitization following an injury can act as a persistent autonomous pain generator after the inducing injury has healed.

METHODS

We searched Medline on PubMed and the Cochrane Library, screening 3,572 abstracts, from which 937 full text articles were obtained, with 186 of these discarded as irrelevant to the question being posed. The remaining 751 articles were studied for evidence.

RESULTS

Fourteen publications were judged to provide weak evidence for the hypothesis of central sensitization as a persisting autonomous pain generator, but none addressed the question directly. No strong evidence for the affirmative answer was found.Sixty-two publications were judged to provide weak evidence for a negative answer, and nine judged to provide strong evidence.Unexpectedly, serious weaknesses were discovered in the literature underpinning the validity of the clinical diagnosis of Central Sensitization in man:(i)  Inappropriate extrapolation, in many publications, of laboratory animal data to humans.(ii) Failure to demonstrate the absence of peripheral pain generators which might be perpetuating Central Sensitization.(iii) Many factors now shown to confound what is being measured by quantitative sensory testing, conditioned pain modulation, and Central Sensitization Inventory.

CONCLUSIONS

We found no evidence proving that central sensitization can persist as an autonomous pain generator after the initiating injury has healed.Our review has also shown that the evidential basis for the diagnosis of CS in individual patients is seriously in question.

Ultrasound-Guided Inactivation of Trigger Points Combined with Muscle Fascia Stripping by Liquid Knife in Treatment of Postherpetic Neuralgia Complicated with Abdominal Myofascial Pain Syndrome: A Prospective and Controlled Clinical Study

Objective

To evaluate ultrasound-guided inactivation of myofascial trigger points (MTrPs) combined with abdominal muscle fascia stripping by liquid knife in the treatment of postherpetic neuralgia (PHN) complicated with abdominal myofascial pain syndrome (AMPS).

Methods

From January 2015 to July 2018, non-head-and-neck PHN patients in the Pain Department, The First Affiliated Hospital of Soochow University, were treated with routine oral drugs and weekly paraspinal nerve block for two weeks. Patients with 2 < VAS (visual analogue scale) score < 6 were subjects of the study. They were assigned into control group 1 (C1, n = 33) including those with PHN and without myofascial pain syndrome (MPS) and control group 2 (C2, n = 33) including those with PHN complicated with MPS and observation group 1 (PL, n = 33) including those with PHN complicated with limb myofascial pain syndrome (LMPS) and observation group 2 (PA, n = 33) including those with PHN complicated with AMPS. All groups received zero-grade treatment: routine oral drugs and weekly paraspinal nerve block. PL and PA groups were also treated step by step once a week: primary ultrasound-guided inactivation of MTrPs with dry needling, secondary ultrasound-guided inactivation of MTrPs with dry and wet needling, and tertiary ultrasound-guided dry and wet needling combined with muscle fascia stripping by liquid knife. At one week after primary treatment, patients with a VAS score > 2 proceeded to secondary treatment. If the VAS score was <2, the treatment was maintained, and so on, until the end of the four treatment cycles. Pain assessment was performed by specialized nurses at one week after each treatment, including VAS score, McGill pain questionnaire (MPQ) score, pressure pain sensory threshold (PPST), and pressure pain tolerance threshold (PPTT). VAS score was used as the main index and VAS <2 indicated effective treatment. At 3 months after treatment, outpatient and/or telephone follow-up was performed. The recurrence rate was observed and VAS > 2 was regarded as recurrence.

Results

At one week after primary treatment, the effective rate was 66.7% in PL group, significantly higher than that in PA group (15.2%, P < 0.05). At one week after secondary treatment, the effective rate was 100% and 37.5% in PL and PA groups, respectively, with significant difference between the groups (P < 0.05). The effective rate increased to 90.6% in PA group at one week after tertiary treatment. At one week after the end of treatment cycles, the scores of VAS and MPQ were significantly lower in C1, PL, and PA groups than in C2 group (P < 0.05), while PPST and PPTT were significantly higher than in C2 group (P < 0.05). There was no significant difference between C1 group and PL group (P > 0.05). At follow-up at 3 months after treatment, the recurrence rate was low in each group, with no significant difference between the groups (P > 0.05).

Conclusion

About 57% of PHN patients with mild to moderate pain are complicated with MPS, and ultrasound-guided inactivation of MTrPs with dry and wet needling can effectively treat PHN patients complicated with LMPS. However, patients with PHN complicated with AMPS need to be treated with ultrasound-guided MTrPs inactivation combined with muscle fascia stripping by liquid knife as soon as possible.

Viscero-visceral hyperalgesia in dysmenorrhoea plus previous urinary calculosis: Role of myofascial trigger points and their injection treatment in the referred area

BACKGROUND

Women with dysmenorrhoea plus symptomatic urinary calculosis experience enhanced pain and referred muscle hyperalgesia from both conditions than women with one condition only (viscero-visceral hyperalgesia). The study aimed at verifying if enhanced dysmenorrhoea persists after urinary stone elimination in comorbid women and if local anaesthetic inactivation of myofascial trigger points (TrPs) in the lumbar area (of urinary pain referral) also relieves dysmenorrhoea.

METHODS

Thirty-one women with dysmenorrhoea plus previous urinary calculosis (Dys+PrCal) and lumbar TrPs, and 33 women with dysmenorrhoea without calculosis (Dys) underwent a 1-year assessment of menstrual pain and muscle hyperalgesia in the uterus-referred area (electrical pain threshold measurement in rectus abdominis, compared with thresholds of 33 healthy controls). At the end of the year, 16 comorbid patients underwent inactivation of TrPs through anaesthetic injections, whereas the remaining 12 received no TrP treatment. Both groups were monitored for another year at the end of which thresholds were re-measured.

RESULTS

In year1, Dys+PrCal presented significantly more painful menstrual cycles and lower abdominal thresholds than Dys, thresholds of both groups being significantly lower than normal (p < .001). Anaesthetic treatment versus no treatment of the lumbar TrP significantly reduced the number of painful cycles during year2 and significantly increased the abdominal thresholds (p < .0001).

CONCLUSION

Viscero-visceral hyperalgesia between uterus and urinary tract may persist after stone elimination due to nociceptive inputs from TrPs in the referred urinary area, since TrPs treatment effectively reverses the enhanced menstrual symptoms. The procedure could represent an integral part of the management protocol in these conditions.

SIGNIFICANCE

A past pain process from an internal organ can continue enhancing pain expression from a painful disease in another neuromerically connected organ (viscero-visceral hyperalgesia) if secondary myofascial trigger points (TrPs) developed in the referred area at the time of the previous visceral disease. Inactivation of these TrPs reverts the enhancement. Assessment and treatment of TrPs in referred areas from past visceral pain conditions should be systematically carried out to better control pain from current diseases in other viscera.