The effect of pressure pain sensitivity and patient factors on self-reported pain-disability in patients with chronic neck pain

Shockwave therapy and fibromyalgia and its effect on pain, blood markers, imaging, and participant experience - a multidisciplinary randomized controlled trial

BACKGROUND

Patients with fibromyalgia experience chronic, widespread pain. It remains a misunderstood disorder with multimodal treatments providing mixed results.

OBJECTIVES

To examine the effects of radial shockwave therapy (RSWT) compared to placebo on pain, pain catastrophizing, psychological indices, blood markers, and neuroimaging. Study-related experiences were also explored qualitatively.

METHODS

Quantitative sensory testing (QST), Visual Analog Scale (VAS), Beighton Scoring Screen (BSS), Pain Catastrophizing Scale (PCS), blood biomarker (Interleukin (IL)-6 and IL-10), and brain fMRI were measured pre- and post-treatment along with a post-treatment survey. The RSWT group received five treatments (one week apart over five-week period) to the three most painful areas (500 shocks at 1.5 bar and 15 Hz, then 1000 shocks at 2 bar and 8 Hz, and finally 500 shocks at 1.5 bar and 15 Hz) versus sham treatment for the placebo group.

RESULTS

There were no statistically significant differences in the BSS for hypermobility (p = .21; d = .74), PCS (p = .70; d = .22), VAS (p = .17-.61; d = .20-.83) scores, QST for skin temperature and stimuli (p = .14-.65; d = .25-.88), and for the pressure pain threshold (p = .71-.93; d = .05-.21). The VAS scores had clinically significant changes (MCID greater than 13.90) with improved pain scores in the RSWT group. Neuroimaging scans revealed no cortical thickness changes. Post-treatment surveys revealed pain and symptom improvements and offered hope to individuals.

CONCLUSION

RSWT was implemented safely, without any negative treatment effects reported, and acted as a pain modulator to reduce sensitivity.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov identification number NCT02760212.

Associations of neck muscle strength and cervical spine mobility with future neck pain and disability: a prospective 16-year study

Background

Neck pain has been associated with weaker neck muscle strength and decreased cervical spine range of motion. However, whether neck muscle strength or cervical spine mobility predict later neck disability has not been demonstrated. In this 16-year prospective study, we investigated whether neck muscle strength and cervical spine mobility are associated with future neck pain and related disability in women pain-free at baseline.

Methods

Maximal isometric neck muscle strength and passive range of motion (PROM) of the cervical spine of 220 women (mean age 40, standard deviation (SD) 12 years) were measured at baseline between 2000 and 2002. We conducted a postal survey 16 years later to determine whether any subjects had experienced neck pain and related disability. Linear regression analysis adjusted for age and body mass index was used to determine to what extent baseline neck strength and PROM values were associated with future neck pain and related disability assessed using the Neck Disability Index (NDI).

Results

The regression analysis Beta coefficient remained below 0.1 for all the neck strength and PROM values, indicating no association between neck pain and related disability. Of the 149 (68%) responders, mean NDI was lowest (3.3, SD 3.8) in participants who had experienced no neck pain (n = 50), second lowest (7.7, SD 7.1) in those who had experienced occasional neck pain (n = 94), and highest (19.6, SD 22.0) in those who had experienced chronic neck pain (n = 5).

Conclusions

This 16-year prospective study found no evidence for an association between either neck muscle strength or mobility and the occurrence in later life of neck pain and disability. Therefore, screening healthy subjects for weaker neck muscle strength or poorer cervical spine mobility cannot be recommended for preventive purposes.

Pain and Function in Chronic Musculoskeletal Pain-Treating the Whole Person

Chronic pain is often associated with functional limitations that have a huge impact on patients' lives. However, despite being relatively common, chronic musculoskeletal pain is still viewed by some as a symptom of another disease rather than its own condition, and is therefore poorly addressed. This is compounded by other challenges in the field, including education gaps for both healthcare professionals and patients, a lack of universal and comprehensive assessment tools, poor societal perceptions of chronic pain, and the current stigma around the use of opioids. Here, we review the current chronic musculoskeletal pain management landscape in the United States and offer professional insight into emerging methods that can be used to improve patient outcomes, in particular, the achievement of meaningful functional goals. This perspective incorporates our combined multidisciplinary (psychiatry, psychology, nursing, physical therapy, and general medicine) experience and insights. We believe that chronic pain is a multifactorial experience and treatment requires an integrated, multidisciplinary approach from a range of healthcare providers. For the best patient outcomes, this team should work together to assess and treat the patient as a whole, addressing their pain and also providing education, empowerment, and support to enable patients to set and achieve meaningful functional goals that will provide real improvement in their quality of life. We believe that the healthcare community should elevate the conversation around chronic musculoskeletal pain management beyond that of just pain, to encompass the meaningful benefits that improvement in functional outcomes brings to patients.

A Cumulative Impact of Psychological and Sensitization Risk Factors on Pain-Related Outcomes

OBJECTIVE

Risk constructs based on psychological risk factors (eg, pain catastrophizing, PC) and sensitization risk factors (eg, pressure pain threshold, PPT) are important in research and clinical practice. Most research looks at individual constructs but does not consider how different constructs might interact within the same individual. An evaluation of the cumulative impact of psychological and sensitization risk factors on pain-related outcomes may help guide us in the risk assessment of patients with pain conditions. The aim of this study is to evaluate the cumulative impact of these psychological (PC) and sensitization (PPT) risk factors on pain-related outcomes (activity avoidance, pain severity, and disability) considering covariates.

METHODS

We included 109 participants (70.60% women; mean ± SD age 53.6 ± 12.3 years) with chronic musculoskeletal pain for data analysis, who completed all measures of this study. Participants completed a single testing session that included measures of risk factors (PC and PPT) and pain-related outcomes (self-reported avoidance, functional avoidance, disability, and pain severity). Subgroups were constructed by dichotomizing of PC and PPT scores, resulting in four groups: (1) low catastrophizing and low sensitivity (N = 26), (2) high catastrophizing and low sensitivity (N = 27), (3) low catastrophizing and high sensitivity (N = 25), and (4) high catastrophizing and high sensitivity (N = 31).

RESULTS

One-way analysis of variance (ANOVA) revealed significant group differences (P < 0.05, η²  = 0.08 to 0.14) in all outcomes of this study (except functional avoidance), and post hoc analysis indicated the significant differences are between group 1 and 4. A cumulative impact is reflected by large effect sizes between group 1 and 4 (d = 0.8 to 1). The group 2 and 3 (one risk dimension groups: either high-PC or high-PPT) represent 47% of the total participants.

CONCLUSIONS

The study suggests both higher level of PC and pressure sensitivity have a cumulative impact on risk screening for pain-related outcomes, considering gender in functional avoidance (task-related outcome). A clinical presentation with high-PC (one dimension of risk) is not associated with high-PPT (another dimension of risk). This finding has important clinical and theoretical implications.

Quantitative sensory testing to evaluate and compare the results after epidural injection and simple discectomy, in patients with radiculopathy secondary to lumbar disc herniation

The objective assessment of the radiculopathy secondary to lumbar disc herniation is essential to optimize treatment. The quantitative sensory test (QST) is a useful tool to evaluate somatosensory nerves. The aim of our study is quantifying by QST the alterations of patients treated by epidural injections (EI) or surgical lumbar decompression (LD). A prospective, cohort study has done in Hospital Universitario Rio Hortega, Valladolid, Spain, between January 2014 and December 2016.The study includes 74 patients (40 men) who underwent EI (50) or LD (24) with lumbar disc herniation and treated by EI or LD. Participants underwent a brief battery of QST at baseline and after 1, 3 and 6 months of follow-up. QST threshold were measured in three series of five warm and cold stimuli (cold detection threshold, warm detection threshold, cold pain threshold, heat pain threshold) bilateral. Additionally, pain assessment (Visual Analogue Scale) and neurological examination was performed. Thermal thresholds were analysed and compared. In the EI group, warm detection threshold (WDT) measurements were significantly lower after 3 and 6 months of follow-up (40.44 ± 3.42°C vs. 38.30 ± 3.73°C and 37.48 ± 4.58°C respectively, p = 0.031 and p = 0.043). LD group showed lower WDT measurements at 1, 3 and 6 months of follow up (40.20 ± 2.97°C vs., 37.98 ± 2.04°C, 37.43 ± 3.80°C and 36.55 ± 2.77°C respectively, p = 0.049, p = 0.032 and p = 0.024) and lower heat pain threshold (HPT) levels after 3 and 6 months of follow-up (48.75 ± 1.37°C vs. 43.26 ± 0.60°C and 42.06 ± 1.37°C respectively, p = 0.037 and p = 0.021). QST explorations were compared between both groups. At 1-month follow-up only the WDT parameter was different, higher in EI group (40.98 ± 4.04°C vs. 37.98 ± 2.04°C, p = 0.043). There were no differences in any parameter measured by QST after 3 and 6-months follow-up between both groups. Epidural injection should be considered the first-step of treatment.

Local and Widespread Pressure Pain Hyperalgesia Is Not Side Specific in Females with Unilateral Neck Pain that Can Be Reproduced during Passive Neck Rotation

Current evidence for widespread hyperalgesia in non-specific neck pain (NSNP) is unclear. It is currently recommended to group NSNP patients according to pain-provoking movements. The aim of this study was to investigate local and widespread pain sensitivity in females with unilateral NSNP that is reproducible during passive neck rotation compared with matched controls, and to compare the side specific effect of pain location on pressure pain sensitivity among females with unilateral NSNP. Thirty-six females with unilateral NSNP evoked during passive ipsilateral (n = 20) or contralateral (n = 16) rotation toward the painful side were compared with 20 controls. Participants reported their pain intensity at rest and during passive neck rotation and completed the Neck Disability Index. Pressure pain thresholds (PPTs) were assessed bilaterally over the anterior scalene; the sternocleidomastoid; the levator scapulae; lateral to the spinous process of C6; the median, ulnar, and radial nerves; and the tibialis anterior. The ANOVA revealed lower PPTs in females with unilateral NSNP compared with the controls (all at p < 0.001), but no differences were found between the sides, nor was there any Group × side interaction. Among females with NSNP, those with higher pain intensity during ipsilateral rotation toward the painful side showed lower PPTs over the anterior scalene, median nerve, ulnar nerve, and tibialis anterior (all, p < 0.05) than females with higher pain intensity during contralateral rotation toward the painful side. These findings demonstrated bilateral local and widespread pressure pain hyperalgesia in females with unilateral NSNP that was reproducible during passive neck rotation compared with controls. There was no side specific effect of pain location on PPTs among females with unilateral NSNP.

Psychometric Properties of Pressure Pain Thresholds Measured in 2 Positions for Adults With and Without Neck-Shoulder Pain and Tenderness

OBJECTIVE

The purpose of this study was to determine the psychometric properties of pressure pain threshold (PPT) testing in adults with and without neck-shoulder pain and tenderness and to compare the differences in PPT measurements between the seated and prone positions.

METHODS

Thirty asymptomatic adults and 30 symptomatic patients with intermittent neck-shoulder pain and tenderness completed the study. A pressure algometer was used to assess PPTs at specific points on the middle deltoid, levator scapulae, and upper trapezius muscles of the dominant side of the asymptomatic individuals and the painful side of the patients. Four trials were performed on each muscle in both the seated and prone positions. To determine between-day reliability, a subset of the participants returned to repeat the testing.

RESULTS

The intraclass correlation coefficients showed good to excellent within-session reliability and fair to excellent between-day reliability of PPT measurements in both the seated and prone positions for both groups. There were significant differences between groups for all muscles in both positions (P < .05) except for the upper trapezius muscle in the prone position. In addition, significant differences were found between the 2 testing positions for the middle deltoid and upper trapezius muscles in the symptomatic group and for the middle deltoid muscle in the asymptomatic group.

CONCLUSION

The results of the study suggest that PPT testing could be useful for distinguishing individuals with and without neck-shoulder pain and tenderness. Further, the patient's position should be considered when testing PPT, specifically at the middle deltoid or upper trapezius muscles.

Self-reported sinus headaches are associated with neck pain and cervical musculoskeletal dysfunction: a preliminary observational case control study

Objectives: Headaches can be associated with rhinosinusitis and may present a diagnostic challenge because of symptomatic overlap with other recurring headaches. Neck pain has received extensive attention in migraine, tension-type and cervicogenic headache but not as a comorbid feature of headache in those with rhinosinusitis. This study investigated the occurrence of neck pain and cervical musculoskeletal dysfunction in individuals with self-reported sinus headaches (SRSH).

Methods: Participants with and without SRSH attended a single data collection session. Participants completed the Headache Impact Test (HIT)-6 and the Sino-Nasal Outcome Test (SNOT)-22. Cervical range of motion (ROM), segmental examination, muscle endurance and pressure-pain threshold (PPT) were measured .

Results: Participants included 31 with SRSH (77.4% female; age 43.7 (9.9) years) and 30 without headache. Average symptom duration was 89.7 (±85.6) months. Mean SNOT-22 and HIT-6 scores were 36.2 (15.3) and 56.7 (7.1), respectively. In the SRSH group, 83.9% (n = 26) reported neck pain. There was a significant difference between groups for cervical sagittal (14.3° [5.3°, 23.3°], p = 0.002) and transverse plane ROM (21.5° [12.4°, 30.6°], p < 0.001), but no difference in frontal plane motion (p = 0.017). There were significant between groups difference in neck flexor endurance (19.5 s [10.1 s, 28.9 s], <0.001), segmental dysfunction O-C4 (p < 0.001) but not in PPT (p = 0.04).

Discussion: Neck pain and cervical musculoskeletal dysfunction are common among persons with SRSH and may be a comorbid feature or contributing factor to headaches attributed to rhinosinusitis. Further research is needed to understand these associations.

Evaluating the novel added value of neurophysiological pain sensitivity within the fear-avoidance model of pain

BACKGROUND

The fear-avoidance model (FAM) is a leading theoretical paradigm for explaining persistent pain following musculoskeletal injury. The model suggests that as injuries heal, pain-related outcomes are increasingly determined by psychological, rather than physiological factors. Increasing literature, however, suggests that neurophysiological processes related to pain sensitivity also play an important role in chronicity. To date, there has been limited research that has specifically explored the role of pain sensitivity within the FAM. This study addresses this gap by evaluating whether clinical measures of pain sensitivity help explain FAM-related outcomes, beyond model-relevant psychological predictors.

METHODS

The study sample consisted of 80 adults with chronic and widespread musculoskeletal pain. Participants completed a single testing session that included measures of all of the major constructs of the FAM, including pain catastrophizing, pain-related fear, activity avoidance (self-report and functional measures), pain-related disability, depression and pain severity, as well as a battery of quantitative sensory testing that included measures of pressure pain threshold and temporal summation of mechanical pain across eight body sites.

RESULTS

A series of hierarchical regression analyses revealed that after controlling for the psychological predictors of the FAM, indices of pain sensitivity significantly predicted 4 of the 5 FAM-related outcomes (p < 0.05). Depression was the only outcome not significantly predicted by pain sensitivity. Interestingly, measures of pain sensitivity, but not FAM psychological factors, predicted the functional measure of activity avoidance.

CONCLUSIONS

These findings provide further evidence for the importance of neurophysiological factors within the FAM and have important clinical and theoretical implications.

SIGNIFICANCE

This study provides evidence for the unique and added value of neurophysiological factors within the Fear Avoidance Model of pain and for the importance of integrating both sensory and psychological factors within both theoretical paradigms and clinical management strategies.

Do Subjects with Whiplash-Associated Disorders Respond Differently in the Short-Term to Manual Therapy and Exercise than Those with Mechanical Neck Pain?

Objective

To compare the short-term effects of manual therapy and exercise on pain, related disability, range of motion, and pressure pain thresholds between subjects with mechanical neck pain and whiplash-associated disorders.

Methods

Twenty-two subjects with mechanical neck pain and 28 with whiplash-associated disorders participated. Clinical and physical outcomes including neck pain intensity, neck-related disability, and pain area, as well as cervical range of motion and pressure pain thresholds over the upper trapezius and tibialis anterior muscles, were obtained at baseline and after the intervention by a blinded assessor. Each subject received six sessions of manual therapy and specific neck exercises. Mixed-model repeated measures analyses of covariance (ANCOVAs) were used for the analyses.

Results

Subjects with whiplash-associated disorders exhibited higher neck-related disability ( P  = 0.021), larger pain area ( P  = 0.003), and lower pressure pain thresholds in the tibialis anterior muscle ( P  = 0.009) than those with mechanical neck pain. The adjusted ANCOVA revealed no between-group differences for any outcome (all P  > 0.15). A significant main effect of time was demonstrated for clinical outcomes and cervical range of motion with both groups experiencing similar improvements (all P  < 0.01). No changes in pressure pain thresholds were observed in either group after treatment ( P  > 0.222).

Conclusions

The current clinical trial found that subjects with mechanical neck pain and whiplash-associated disorders exhibited similar clinical and neurophysiological responses after a multimodal physical therapy intervention, suggesting that although greater signs of central sensitization are present in subjects with whiplash-associated disorders, this does not alter the response in the short term to manual therapy and exercises.

Evaluation of Pressure Pain Threshold as a Measure of Perceived Stress and High Job Strain

OBJECTIVE

To investigate whether pressure pain threshold (PPT), determined by pressure algometry, can be used as an objective measure of perceived stress and job strain.

METHODS

We used cross-sectional base line data collected during 1994 to 1995 within the Project on Research and Intervention in Monotonous work (PRIM), which included 3123 employees from a variety of Danish companies. Questionnaire data included 18 items on stress symptoms, 23 items from the Karasek scale on job strain, and information on discomfort in specified anatomical regions was also collected. Clinical examinations included pressure pain algometry measurements of PPT on the trapezius and supraspinatus muscles and the tibia. Associations of stress symptoms and job strain with PPT of each site was analyzed for men and women separately with adjustment for age body mass index, and discomfort in the anatomical region closest to the point of pressure algometry using multivariable linear regression.

RESULTS

We found significant inverse associations between perceived stress and PPT in both genders in models adjusting for age and body mass index: the higher level of perceived stress, the lower the threshold. For job strain, associations were weaker and only present in men. In men all associations were attenuated when adjusting for reported discomfort in regions close to the site of pressure algometry. The distributions of PPT among stressed and non-stressed persons were strongly overlapping.

CONCLUSIONS

Despite significant associations between perceived stress and PPT, the discriminative capability of PPT to distinguish individuals with and without stress is low. PPT measured by pressure algometry seems not applicable as a diagnostic tool of a state of mental stress.

Psychophysical and Patient Factors as Determinants of Pain, Function and Health Status in Shoulder Disorders

Objective:

To estimate the extent to which psychophysical quantitative sensory test (QST) and patient factors (gender, age and comorbidity) predict pain, function and health status in people with shoulder disorders. To determine if there are gender differences for QST measures in current perception threshold (CPT), vibration threshold (VT) and pressure pain (PP) threshold and tolerance.

Design:

A cross-sectional study design.

Setting:

MacHAND Clinical Research Lab at McMaster University.

Subjects:

34 surgical and 10 nonsurgical participants with shoulder pain were recruited.

Method:

Participants completed the following patient reported outcomes: pain (Numeric Pain Rating, Pain Catastrophizing Scale, Shoulder Pain and Disability Index) and health status (Short Form-12). Participants completed QST at 4 standardized locations and then an upper extremity performance-based endurance test (FIT-HaNSA). Pearson r’s were computed to determine the relationships between QST variables and patient factors with either pain, function or health status. Eight regression models were built to analysis QST’s and patient factors separately as predictors of either pain, function or health status. An independent sample t-test was done to evaluate the gender effect on QST.

Results:

Greater PP threshold and PP tolerance was significantly correlated with higher shoulder functional performance on the FIT-HANSA (r =0.31-0.44) and lower self-reported shoulder disability (r = -0.32 to -0.36). Higher comorbidity was consistently correlated (r =0.31-0.46) with more pain, and less function and health status. Older age was correlated to more pain intensity and less function (r =0.31-0.57). In multivariate models, patient factors contributed significantly to pain, function or health status models (r² =0.19-0.36); whereas QST did not. QST was significantly different between males and females [in PP threshold (3.9 vs. 6.2, p < .001) and PP tolerance (7.6 vs. 2.6, p < .001) and CPT (1.6 vs. 2.3, p =.02)].

Conclusion:

Psychophysical dimensions and patient factors (gender, age and comorbidity) affect self-reported and performance-based outcome measures in people with shoulder disorders.