Clinical Characteristics of Myofascial Pain Syndrome with Psychological Stress in Patients with Cancer

Trigger point injections for myofascial pain in terminal cancer: a randomized trial

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of a single trigger point injection (TPI) of a local anesthetic for the treatment of myofascial pain syndrome (MPS) in patients with incurable cancer.

METHODS

This multicenter, exploratory, open-label, randomized comparative trial was conducted in five specialized palliative care departments. Hospitalized patients with incurable cancer who had been experiencing pain related to MPS were randomized to receive either a TPI of 1% lidocaine plus conventional care (TPI group) or conventional care alone (control group). The short-term efficacy and occurrence of adverse events (AEs) were compared between groups. The primary endpoint was the percentage of patients who experienced a reduction in pain scores of ≥50%, assessed using an 11-point Numerical Rating Scale, at 3 days post-intervention. Adverse events were assessed using the Common Terminology Criteria for AEs v5.0.

RESULTS

Fifty patients were enrolled, and the trial completion rate was 100%. The proportion of patients who experienced an improvement in Numerical Rating Scale pain scores of ≥50% was 70.8% (95% confidence interval, 52.4%-89.2%) in the TPI group and 0.0% in the control group; the difference was statistically significant (P < .001). In the TPI group, one case (4.2%) of Grade 1 nausea and 1 case (4.2%) of Grade 1 somnolence were reported.

CONCLUSION

A single TPI of a local anesthetic is safe and efficacious in inducing an immediate reduction in MPS-related pain in patients with incurable cancer. Clinical trials registration number: This study was registered with the Japan Registry of Clinical Trials (approval number: jRCTs051210132) on December 16, 2021. https://jrct.niph.go.jp/en-latest-detail/jRCTs051210132.Approval of the research protocol by a Certified Review Board: The present study was approved by the Wakayama Medical University (reference number: CRB5180004. Registered 26 May 2021).

Myofascial pain syndrome in patients with cancer: a narrative review

PURPOSE

Myofascial pain syndrome (MPS) is a chronic musculoskeletal pain syndrome. The purpose of this review is to describe the epidemiological and treatment evidence and to address the future research agenda in patients with cancer.

METHODS

A narrative review of previous reports investigating the prevalence and treatment of MPS in the oncology field is presented. The target population is patients with cancer and cancer survivors.

RESULTS

There have been three prospective and two retrospective studies investigating the prevalence of MPS. MPS is as high as 38%-45% in patients with advanced or incurable cancer and 11.9%-44.8% in cancer survivors. A total of nine reports investigated the efficacy of the following interventions: trigger point injection (TPI), myofascial techniques and ischaemic compression. TPI has been reported to be effective in four observational studies. One randomised study reported the efficacy of myofascial techniques, but two randomised studies reported no added beneficial effects of it in breast cancer survivors. Two randomised studies investigated the efficacy of ischaemic compression, but the obtained results were contradictory.

CONCLUSIONS

MPS is highly prevalent. We should know that non-cancer pain is also common in both patients with cancer and survivors. In treating such pain, careful physical examination is essential. Then, non-pharmacological treatment should be considered as well as pharmacotherapy. As evidence regarding MPS in the oncology field is scarce, further research is warranted.

A secondary analysis: the impact of pre-existing chronic pain among patients with cancer presenting to the emergency department with acute pain

PURPOSE

Patients with cancer may experience pain from cancer itself or its treatment. Additionally, chronic pain (CP) predating a patient's cancer diagnosis may make the etiology of pain less clear and the management of pain more complex. In this brief report, we investigated differences in biopsychosocial characteristics, pain severity, and opioid consumption, comparing groups of cancer patients with and without a history of CP who presented to the emergency department (ED) with a complaint of cancer-related pain.

METHODS

This secondary analysis of a prospective cohort study included patients with cancer who presented to the ED with a complaint of pain (≥ 4/10). Sociodemographic, clinical, psychological, and pain characteristics were assessed in the ED and subsequent hospitalization. Mann-Whitney U-, T-, and Chi-square tests were used to compare differences between patients with and without pre-existing CP before cancer.

RESULTS

Patients with pre-existing CP had lower income (p = 0.21) and less formal education (p = 0.25) and were more likely to have a diagnosis of depression or substance use disorder (p < 0.01). Patients with pre-existing CP reported significantly greater pain severity in the ED and during hospitalization compared to those without pre-existing CP (p < 0.05), despite receiving greater amounts of opioid analgesics (p = 0.036).

CONCLUSION

Identifying a history of pre-existing CP during intake may help identify patients with cancer with difficult to manage pain, who may particularly benefit from multimodal interventions and supportive care. In addition, referral of these patients for the management of co-occurring pain disorders may help decrease the usage of the ED for undertreated pain.

Effect of visual feedback during ultrasound-guided hydrodissection for myofascial pain syndrome: An exploratory, prospective, observational clinical trial on the expectations for treatment

Expectations for treatment have a favorable effect on the subsequent course of pain and behavior in patients. It is not known whether receiving hydrodissection while patients view their ultrasound image with doctors (visual feedback) is associated with positive treatment expectations. This was an exploratory, prospective, observational clinical trial. We explored the possibility that visual feedback immediately after ultrasound-guided hydrodissection increases the expectations for treatment, which could be one of the related factors for pain reduction. Treatment expectations were set as mediators of pain using path analysis. The primary endpoint was the numerical rating scale to assess expectations for treatment immediately after hydrodissection, between with and without the visual feedback. During 2019 and 2020, 136 outpatients received ultrasound-guided hydrodissection for myofascial pain syndrome. Of these, 65 (47.8%) patients received visual feedback during ultrasound-guided hydrodissection. Compared with the non-visual feedback group, the visual feedback group had higher expectations for treatment immediately after hydrodissection, and their expectations were maintained at day 14 of treatment (p < 0.001). A numerical rating scale (NRS) to assess expectations for treatment was similar before hydrodissection and immediately after hydrodissection was 8.4 (standard deviations, 1.6) in the visual feedback and 5.9 (standard deviations, 2.6) in the visual feedback. The proportion of increased expectations immediately after hydrodissection was 90.8% (95% CI: 83.7-97.9) in visual feedback group and 38.0% (95% CI: 26.7-49.3) in non-visual feedback group (p < 0.001). In the visual feedback group, 67.7% of patients showed improvement in pain numerical rating scale score by 50% or more at day 14, whereas such improvement was observed in only 36.6% of the non-visual feedback group (p < 0.001). Based on path analysis, the visual feedback had the greatest influence on pain numerical rating scale reduction at 14 days, indirectly due to increased expectations for treatment as a mediator (β = 0.434). However, the adjusted R ² values, which is the overall fit of the model, was low at 0.298. Visual feedback during ultrasound-guided hydrodissection increases the expectations for treatment immediately after hydrodissection, which could be one of the related factors for pain reduction in patients with myofascial pain syndrome.

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.

DESIGN AND METHODS

This was a multi-center, 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 1.18-9.02, p = 0.023).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 < 0.001).

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.

The Usefulness of the Armchair Sign for the Diagnosis of Psychosomatic-Prone Myofascial Pain Syndrome in Patients with Incurable Cancer: A Secondary Analysis of a Prospective Multicenter Observational Clinical Study

Background: Because psychosomatic diseases are pathological conditions, it is difficult to identify their degrees. The armchair sign is a test used to assess voluntary muscle relaxation.

Objective: We aimed to evaluate the usefulness of the armchair sign for the diagnosis of psychosomatic-prone myofascial pain syndrome (MPS) in patients with incurable cancer.

Design: This was a secondary analysis of a prospective multicenter observational clinical study.

Setting/Patients: Patients with incurable cancer who were referred to palliative care services at five institutions in Japan between March 2018 and December 2018.

Results: A total of 101 patients were enrolled, of whom 44 met MPS diagnostic criteria. Of these, 27 patients (61.3%) had psychosomatic-prone MPS. There was a significant association between the armchair sign and psychosomatic-prone MPS (p = 0.002). Sensitivity and specificity were 40.7% (95% confidence interval [CI]: 18.0–63.4) and 100.0%, respectively. The area under the curve score was 0.704 (95% CI: 0.553–0.855).

Conclusions: The armchair sign may be useful as an ancillary test for the diagnosis of psychosomatic-prone MPS in patients with incurable cancer.

Trial Registration: UMIN000031338. Registered February 16, 2018.

Clinical Characteristics of Noncancer-Related Upper Back Pain on Initiation of Palliative Care in Patients with Incurable Cancer

Background: Cancer patients experience various types of pain unrelated to their malignancy. However, no previous study has reported the prevalence of noncancer-related pain among patients with incurable cancer.

Objective: We aimed to investigate the frequency of noncancer-related upper back pain, the type of noncancer disease, and pain intensity among patients.

Design: This is a multicenter cross-sectional survey.

Setting/Subjects: Subjects were patients with incurable cancer who underwent initiation of palliative care at two university hospitals in Japan.

Measurements: Data for patient characteristics were recorded, and the upper back pain intensity, duration, analgesic use, and opioid drug use with dose were determined. Appropriate statistical tests were also performed.

Results: Among the 103 patients with upper back pain, 20 (19.4%) had cancer-related pain, 28 (27.2%) had both cancer- and noncancer-related pain, and 53 (51.5%) had only noncancer-related pain. Myofascial pain was suspected in the 72 (88.9%) participants with noncancer-related pain. The median pain numerical rating scale score was four in the cancer-related pain group and seven in the other two groups (p = 0.005).

Conclusions: A high proportion of outpatients with incurable cancer undergoing palliative care initiation had noncancer-related upper back pain. Severe pain at the initiation of palliative care in patients with incurable cancer may include noncancer-related pain. Trial Registration: UMIN000038371. Registered December 1, 2019.