Recognition of central sensitization in patients with musculoskeletal pain: Application of pain neurophysiology in manual therapy practice

Effectiveness of movement representation techniques in non-specific shoulder pain: a systematic review and meta-analysis

This systematic review and meta-analysis aims to assess the effects of movement representation techniques (MRT) on pain, range of motion, functional outcomes, and pain-related fear in patients with non-specific shoulder pain (NSSP). A literature search conducted in PubMed, PEDro, EBSCO, Scopus, Cochrane Library, ScienceDirect, and gray literature on April 31, 2023. We selected seven randomized controlled trials based on the PICOS framework. Incomplete data or non-NSSP excluded. Study quality was assessed using the PEDro scale (mean score = 6.43), and certainty of evidence was evaluated with the GRADE approach. MRT demonstrated a large effect size for pain reduction (high heterogeneity, I2 = 85.2%, Hedges'g = 1.324, 95% CI = 0.388-2.260, P = 0.006), functional improvement (moderate heterogeneity, I2 = 70.82%, Hedges'g = 1.263, 95% CI = 0.622-1.904, P < 0.001), and reduction of pain-related fear (moderate heterogeneity, I2 = 70.86%, Hedges'g = 0.968, 95% CI = 0.221-1.716, P < 0.001). MRT also showed significant benefits for range of motion, particularly in flexion (low heterogeneity, I2 = 26.38%, Hedges'g = 0.683), abduction (low heterogeneity, I2 = 33.27%, Hedges'g = 0.756), and external rotation (low heterogeneity, I2 = 48.33%, Hedges'g = 0.542) (P < 0.001 for all), while no significant effect was found for internal rotation (P > 0.05). No publication bias was detected. While limited evidence and methodological concerns necessitate further research, MRT appears to positively impact pain, range of motion, functional outcomes, and pain-related fear in NSSP patients.

The Association Between the Central Sensitisation Inventory and Temporomandibular Disorders Is Confounded by Migraine, Depression, Widespread Pain and Parafunction. A Cross-Sectional Telehealth Study

BACKGROUND

Temporomandibular disorders (TMDs) are conditions that involve the temporomandibular joints, masticatory muscles, and associated tissues, causing orofacial pain. Central sensitisation (CS) is a relevant part of the TMD pathophysiology. Migraine, psychological aspects, parafunctional oral habits and widespread pain are commonly associated with both TMD and CS and could confound the association between them.

OBJECTIVES

To investigate the association between painful TMD and the Central Sensitisation Inventory (CSI) score, and to assess the presence of confounders in this association.

METHODS

Cross-sectional study that assessed women with and without orofacial pain complaints using telehealth. The TMD Pain Screener and an online physical examination determined the presence of painful TMD. The following questionnaires were applied: CSI, Headache Screening Questionnaire, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Oral Behavior Checklist, Jaw Functional Limitation Scale and the Nordic musculoskeletal questionnaire. A single regression investigated the association between the CSI score and TMD, and a multiple regression investigated the effect of the other outcomes as possible confounders. Confounding was considered present when the association between TMD and the CSI score changed more than 10% after adding a possible confounder to the regression model.

RESULTS

Forty-two women with painful TMD and 53 without TMD were included. There was a significant association between the CSI score and the presence of painful TMD (R2 = 0.639; p < 0.001). This association changed when the following outcomes were added to the model: presence of migraine, symptoms of depression, widespread pain and parafunctional oral habits.

CONCLUSION

The positive association between TMD and the CSI score was confounded by migraine, symptoms of depression, widespread pain and parafunctional oral habits.

Pain hypersensitivity, sensorimotor impairment, and decreased muscle force in a novel rat model of radiation-induced peripheral neuropathy

INTRODUCTION

Radiation-induced peripheral neuropathy is a rare, but serious complication often resulting in profound morbidity, life-long disability, and chronic debilitating pain. Unfortunately, this type of peripheral neuropathy is usually progressive, and almost always irreversible. To date, a standardized rat model of radiation-induced peripheral neuropathy has not been established. The purpose of the present study was to examine neuropathic pain, sensorimotor impairment, and muscle force parameters following the administration of a clinically relevant radiation dose in a rat model.

METHODS

Ten rats were randomly assigned to one of two experimental groups: (1) radiation and (2) sham-radiated controls. Radiated animals were given a clinically relevant dose of 35 Gray (Gy) divided into five daily doses of 7 Gy/day. This regimen represents a human equivalent dose of 70 Gy, approximating the same dosage utilized for radiotherapy in oncologic patients. Sham-radiated controls were anesthetized and placed in the radiation apparatus but were not given radiation. All animals were tested for baseline values in both sensorimotor and pain behavioral tests. Sensorimotor testing consisted of the evaluation of walking tracks with the calculation of the Sciatic Functional Index (SFI). Pain-related behavioral measures consisted of mechanical allodynia (von Frey test), cold allodynia (Acetone test), and thermal allodynia (Hargreaves test). Animals were tested serially over an 8-week period. At the study endpoint, electrophysiological and muscle force assessments were completed, and histomorphometric analysis was performed on all sciatic nerves.

RESULTS

Animals that underwent radiation treatment displayed significantly greater pain hypersensitivity to mechanical stimulation as compared to sham radiated controls from weeks 4 to 8 of testing. SFI values indicated sensorimotor impairments in the overground gait of radiated animals as compared to non-radiated animals. Furthermore, radiated animals displayed reduced twitch and tetanic muscle force when compared to sham radiated controls.

CONCLUSIONS

A clinically relevant human equivalent dose of fractionated 35 Gy in rats established significant pain hypersensitivity, impairments in sensorimotor locomotion, and decreased muscle force capacity. This novel rodent model of radiation-induced peripheral neuropathy can be utilized to assess the potential efficacy of therapeutic treatments to either prevent or remediate this clinically debilitating condition.

Exploring signs of central sensitization in adolescents with hypermobility Spectrum disorder or hypermobile Ehlers-Danlos syndrome

BACKGROUND

Hypermobility Spectrum Disorder (HSD) and Hypermobile Ehlers-Danlos Syndrome (hEDS) are two overlapping heritable connective tissue disorders characterized by joint hypermobility, chronic pain, impaired body perception, and musculoskeletal symptoms. Central sensitization has been proposed as a plausible explanation for symptoms like widespread pain, fatigue, mood disorders, and sleep disturbances in patients with HSD/hEDS.

OBJECTIVE

The aim of this study was to investigate signs of central sensitization, including exercise-induced hypoalgesia (EIH), and fatigue severity in adolescents with HSD/hEDS.

METHODS

In this prospective, experimental, case-control study, thirty-seven adolescents with HSD/hEDS and 47 healthy adolescents (all aged 13-17 years) were included. Pressure pain thresholds (PPTs) were measured at four muscle groups using a pressure algometer. EIH was evaluated by measuring PPTs on two muscle groups immediately after an exercise test on a bicycle ergometer. Participants also completed questionnaires on fatigue and cognitive/emotional factors.

RESULTS

The study demonstrated significantly lower PPTs in four different muscle groups in adolescents with HSD/hEDS compared to the healthy control group. Both groups achieved a significantly higher PPTs after exercise in the muscle involved in the activity. Adolescents with HSD/hEDS reported higher fatigue levels and more cognitive/emotional difficulties than the control group.

CONCLUSION

Adolescents with HSD/hEDS showed generalized hyperalgesia measured through PPTs at different body sites. EIH was partly affected in adolescents with HSD/hEDS, presenting as unchanged pain sensitivity in the remote muscle. Pain should be considered as a phenomenon that is influenced by different biopsychosocial factors, including possible central sensitization, which increase its complexity.

SIGNIFICANCE STATEMENT

This study breaks new ground by showing signs of central sensitization, including diminished EIH, in adolescents with HSD or hEDS. Given that exercise is a key element in pain management, these findings offer valuable insights when developing treatment plans for adolescents with HSD or hEDS.

Do measures of central sensitization relate to movement-evoked pain in people with chronic low back pain? A longitudinal prospective study

BACKGROUND

One of the most frequent complaints among people with musculoskeletal pain is pain during physical activity, commonly referred to as movement-evoked pain. It is suggested to be associated with quantitative sensory testing measures of central pain process in individuals with musculoskeletal pain.

OBJECTIVE

To investigate the predictive association between movement-evoked pain scores and measures of central sensitization in patients with chronic nonspecific low back pain. The secondary aim was to determine whether changes in movement-evoked pain scores are associated with changes in measures of central sensitization.

METHODS

In this longitudinal prospective study, 50 participants with chronic low back pain were included. Pain pressure thresholds, temporal summation of pain, descending pain modulation, and the central sensitization index were assessed as measures of central sensitization. Movement-evoked pain was evaluated using the Back Performance Scale and a 5-minute walk test.

RESULTS

Measures of central sensitization, specifically pressure pain thresholds and temporal summation, demonstrated predictive associations with movement-evoked pain measures. In response to treatment, improvements in movement-evoked pain were associated with improvements in measures of central sensitization (i.e., pressure pain thresholds and temporal summation) and improved pressure pain thresholds in the plantar toe significantly predict movement-evoked pain measures experienced during the 5-minute walk test.

CONCLUSIONS

These results imply that movement-evoked pain is related to processes related to central modulation of pain in patients with nonspecific chronic low back pain.

What are the functional and clinical characteristics shared by fibromyalgia and low back pain? A scoping review

BACKGROUND

Fibromyalgia and chronic primary low back pain are two chronic pain conditions with a significant biopsychosocial burden. Recently, the International Association for the Study of Pain has grouped them under the term chronic primary pain. To further explore similarities and differences between these two conditions, the objective of this scoping review is to explore the pain-related, physiological and psychological outcomes in individuals with fibromyalgia and low back pain.

METHODS

The following databases were used to find relevant studies, using the PRISMA guidelines: Medline, Psycinfo, and CINAHL. Studies were included if they encompassed both participants with fibromyalgia or low back pain, with the objective to compare pain-related, physiological and/or psychological outcomes.

RESULTS

Nineteen studies were selected for extraction. Among the 2801 participants, 968 had fibromyalgia (mean age 48.56 ± 7.97 years, with 94% being female) and 896 had low back pain (mean age 47.48 ± 8.15 years, with 80% being female). Pain sensitivity, physical dysfunction, illness perception, psychological distress, alexithymia, depression, and anxiety were generally more severe in participants with fibromyalgia. Most studies found similar levels of pain intensity, kinesiophobia, quality of pain, quality of life, impact of pain, suicidal risk, anger, and social support comparing individuals with fibromyalgia and individuals with low back pain.

DISCUSSION

This scoping review highlights that although both conditions show similar pain intensity and impact on quality of life, fibromyalgia is associated with greater overall severity than low back pain, especially in sensitivity to pain and depression/anxiety.

[Current knowledge of German physiotherapy trainees and students on pain and the influence of a teaching intervention]

BACKGROUND

In order to properly inform patients about their pain and initiate targeted therapies, it is important for physiotherapists to learn about the latest scientific evidence on pain during their training.

AIM

This study aimed to assess the pain knowledge of German physiotherapy trainees and students. In addition, the influence of a teaching intervention (Pain Neuroscience Education, PNE) on their pain knowledge was investigated.

METHODS

An online test was performed, which contained the German versions of the revised Neurophysiology of Pain Questionnaire (rNPQ-D) and the Essential Knowledge of Pain Questionnaire (EKPQ). This test was completed by physiotherapy trainees and students (N = 279) in their final semester of vocational education or graduation under virtual supervision. After the test, a sub-cohort of physiotherapy trainees (n = 31) received a four-hour online teaching intervention (PNE), whereupon two retests took place.

RESULTS

The mean rNPQ-D score (63.8%) was significantly higher than the mean EKPQ score (28.4%) (p < 0.001). There was a significant positive correlation between the scores of rNPQ-D and EKPQ (r = 0.365, p < 0.001). Undergraduate students from university (n = 142) achieved significantly higher scores in both questionnaires (p < 0.001) compared to trainees from vocational schools (n = 137). In the sub-cohort, the online teaching intervention significantly improved the scores of both questionnaires immediately (p < 0.001) and six weeks after intervention (p < 0.001).

CONCLUSION

The knowledge of German physiotherapy students about pain seems to be insufficient for an evidence-based treatment of pain patients. A PNE-based online learning program with the latest scientific evidence can significantly improve physiotherapy students' knowledge about pain.

Utilization of Blood Flow Restriction Therapy with a Former Triathlete After Total Knee Arthroplasty: A Case Report

Introduction and Purpose

Knee osteoarthritis (OA) is a common condition that limits function and reduces quality of life. Total knee arthroplasty (TKA) is a surgical procedure that replaces the joint surfaces to address anatomical changes due to knee OA. While TKA improves symptoms and function, postoperative impairments are common, including reduced quadriceps strength. Blood flow restriction (BFR) may be a viable option for patients following TKA, as it can improve strength with a minimal amount of joint loading compared to traditional strength training. The purpose of this case report is to describe the impact of BFR use in an individual after TKA, employing pain measurements, quantitative sensory testing, patient-reported outcome measures, physical performance tests, and muscle strength and power testing to explore potential treatment effects and identify potential predictors of response for future studies.

Case Description

A 49-year-old former female triathlete with a history of knee injury and arthroscopic surgery underwent a right TKA and sought physical therapy (PT) due to pain, limited range of motion (ROM), and knee instability during weight bearing activity. PT interventions included manual therapy, gait training, and a home program. Despite participating in supervised PT, she had persistent pain, ROM deficits, and muscle weakness 16 weeks following TKA. BFR was incorporated into her home program, 16-weeks postoperatively. The Short Form McGill Pain Questionnaire-2 (SF-MPQ-2) and Numeric Pain Rating Scale (NPRS) were used to measure pain. Quantitative sensory testing included pressure pain threshold (PPT) and two-point discrimination (TPD) to measure change in sensory perception. Patient-reported outcome measures to assess perceived physical function were the Knee injury and Osteoarthritis Outcome Score (KOOS) and the KOOS- Joint Replacement (KOOS-JR). Physical performance was measured through the 30-second fast walk test (30SFW), timed stair climb test (SCT), 30-second chair standing test (CST), and the timed up and go (TUG). Knee ROM was assessed through standard goniometry. Knee extensor and flexor muscle strength and power were measured with an instrumented dynamometer for isokinetic and isometric testing, generating a limb symmetry index (LSI).

Outcomes

Pain and quantitative sensory testing achieved clinically meaningful improvement suggesting reduced sensitivity during and after BFR utilization. Perceived physical function and symptoms significantly improved, particularly in sports and recreation activities, and were best captured in the KOOS, not the KOOS-JR. Physical performance reached clinically meaningful improvement in walking speed, chair stand repetitions, and timed stair climb tests after BFR. Isokinetic and isometric strength and power in knee extensors and flexors increased significantly after BFR compared to the uninvolved leg as determined by LSI.

Discussion

In this case, BFR appeared to be a safe and well-tolerated intervention. The results suggest potential benefits in terms of increased function, strength, power, and reduced pain in this specific person after TKA. Comprehensive pain and sensory assessments alongside clinical measures may help identify suitable patients for BFR after TKA. The KOOS-Sport & Recreation subscale may be more responsive to monitor functional recovery compared to the KOOS-JR, possibly due to the subject's athletic background.

Level of Evidence

4.

Pain intensity and opioid consumption after temporary and permanent peripheral nerve stimulation: a 2-year multicenter analysis

OBJECTIVE

Peripheral nerve stimulation (PNS) is an emerging neuromodulation modality, yet there remains limited data highlighting its long-term effectiveness. The objective of this study was to report real-world data on pain intensity and opioid consumption after temporary and permanent PNS for chronic pain up to 24 months postimplantation.

METHODS

A retrospective study was conducted on all patients who received PNS implants at a multi-centered enterprise between January 1, 2014 and February 24, 2022. The two co-primary outcomes were: (1) change in pain intensity (11-point Numerical Rating Scale) from baseline to 12 months postimplant; and (2) comparison of the change in pain intensity between temporary and permanent PNS cohorts 12 months postimplant.

RESULTS

126 patients were included in this analysis. Pain intensity significantly decreased 12 months postimplant in the overall cohort (mean difference (MD) -3.0 (95% CI -3.5 to -2.4), p<0.0001). No significant difference in this reduction was identified between temporary and permanent PNS cohorts (MD 0.0 (95% CI -1.1 to 1.0), p=1.00) 12 months postimplantation. Pain intensity significantly decreased in the overall, temporary, and permanent cohorts at all secondary time points (3, 6, and 24 months). No change in daily opioid consumption was observed at 6 and 12 months postimplant in the overall cohort.

CONCLUSION

This study found that both temporary and permanent PNS may be effective for reducing pain intensity in patients with chronic pain up to 24 months postimplantation, although no changes in opioid consumption were observed. The decrease in pain intensity was comparable between patients receiving temporary versus permanent implants, highlighting that temporary PNS may achieve long-lasting clinical benefits. However, given the substantial loss to follow-up, further large-scale studies are needed to solidify conclusions about the efficacy of PNS.

Therapeutic Patient Education as Part of the Physiotherapy Management of Adults with Headache: A Scoping Review

PURPOSE OF REVIEW

Physiotherapy interventions for headache mostly include exercise and manual therapy. Yet, the complex nature of headache, sometimes characterized by symptoms of facilitated central pain mechanisms, demands an individualized approach in which therapeutic patient education could be supportive. This scoping review aimed to summarize the position of therapeutic patient education within the physiotherapy management of adults with headache. PubMed, EMBASE, Web of Science, and Scopus were searched. The search-query comprised terminology relating to "headache", "education", and "physiotherapy". Eligibility criteria were: adults with headache, interventions including education within the domain of physiotherapy, reviews, clinical trials, cohort, case report, case-control studies.

RECENT FINDINGS

Eleven publications were included from the 281 retrieved publications. These publications were clinical trials (n = 4), reviews (n = 4), case-reports (n = 2), and a guideline (n = 1). Type of headaches studied were migraine (n = 3), post-traumatic headache (n = 2), tension-type headache (n = 2), cervicogenic headache (n = 1), primary headaches (n = 1), chronic daily headache (n = 1), and mixed migraine-cervicogenic headache (n = 1). Education seems an umbrella-term for postural education, lifestyle advice, and pain education. Three themes emerged across the publications: handling headache triggers (migraine, post-traumatic headache), promoting active lifestyle (post-traumatic headache, chronic daily headache, migraine), evaluating posture (post-traumatic headache, chronic daily headache, tension-type headache, cervicogenic headache). All publications recommended education in the management of headache. Only one (of the 11 included) publication described the educational program and determined its efficacy. Based on this scoping review, therapeutic patient education seems supported within physiotherapy management of headache. However, it is unclear how such education is tailored to the specific needs of the individual, the headache subtype, or when it should be added to physiotherapy management of headache.

The effects of end-range interventions in the management of primary adhesive capsulitis of the shoulder: a systematic review and meta-analysis

PURPOSE

To compare the effects of end-range manual therapy versus other conservative intervention on pain intensity, shoulder range of movement (ROM), and physical function in adhesive capsulitis (AC).

METHODS

Two reviewers conducted a comprehensive search from inception to December 2022. PUBMED, Cochrane Library, CINAHL, EMBASE, and PEDro databases were searched. Clinical trials investigating the effects of end-range mobilisation techniques on pain, ROM, and physical function in patients with AC were included. Methodological quality was evaluated using the PEDro scale, and bias risk was assessed using the Cochrane Collaboration tool. GRADE was used to assess the certainty of the evidence. Data were presented using forest plots, and the random effects models were applied according to the Cochrane handbook.

RESULTS

Ten randomised controlled trials were reviewed, involving 424 AC patients aged 20-70 years. Methodological quality of studies ranged from high to low. The end-range mobilisation showed improvements in pain intensity, shoulder abduction, internal rotation, and external rotation, and physical function compared to other conservative interventions in the short-and medium-terms. Certainty of the evidence was downgraded to very low.

CONCLUSIONS

Very low certainty evidence suggests that end-range mobilisation techniques improve pain intensity, shoulder ROM, and physical function in the short-and medium-term in AC.

Effect of dry needling on pain and central sensitization in women with chronic pelvic pain: A randomized parallel-group controlled clinical trial

Chronic pelvic pain (CPP) is a debilitating problem in women with clear evidence of myofascial dysfunction. It seems that Myofascial trigger points (MTrPs) contribute to the development of central sensitization (CS). This study aimed to investigate the effect of dry needling on pain and CS in women with CPP. Thirty-six women with CPP participated in this randomized controlled clinical trial and randomly assigned into three groups: dry needling group (DNG), placebo needling group (PNG) and control group (CG). The DNG received five sessions of DN using the "static needling", the PNG received non-penetrating method, and the CG did not receive any intervention. Assessment of outcomes including central sensitization inventory (CSI), short-form McGill pain questionnaire (SF-MPQ), electroencephalography (EEG), conditioned pain modulation (CPM), salivary cortisol concentration, 7-item general anxiety disorder scale (GAD-7), pain catastrophizing scale (PCS), and SF-36 questionnaire was performed pre-intervention, post-intervention, and three months post-intervention by a blind examiner. The result showed a significant group-by-time interaction for CSI, SF-MPQ, and PCS. There was a significant decrease in CSI score in post-intervention and three-months post-intervention compare to pre-intervention in the DNG and PNG. SF-MPQ-PPI score in DNG significantly decreased post-intervention. PCS-Total score decreased significantly post-intervention in DNG and PNG. No significant group-by-time interactions were observed for other variables. EEG results showed regional changes in the activity of frequency bands in both eye closed and eye open conditions. It seems that DN can affect central pain processing by removing the source of peripheral nociception. Trial registration: Iranian Registry of Clinical Trials (IRCT20211114053057N1, registered on: December 03, 2021. https://irct.behdasht.gov.ir/search/result?query=IRCT20211114053057N1).

The effect of joint position sense therapy on chronic shoulder pain with central sensitization

BACKGROUND

Chronic shoulder pain is a common musculoskeletal problem associated with unreleased pain and functional dysfunction that can evolve into central sensitization. Some forms of manual therapy may exacerbate pain and central sensitization. This study investigated the impact of joint position sense therapy (JPST), a moderate joint proprioception training technique, on central sensitization, shoulder functional dysfunction, and pain in patients with chronic shoulder pain compared with more intense exercises or aggressive manual therapies.

METHODS

We assessed the pressure pain threshold (PPT) in 30 patients with and 30 patients without chronic shoulder pain. The assessment focused on 4 muscle sites: deltoid, upper trapezius, brachioradialis, and tibialis anterior. Thirty patients with chronic shoulder pain were randomly divided into the JPST and control groups. The JPST group underwent additional shoulder joint position-sense training. The efficiency outcomes were the disabilities of the arm, shoulder, and hand questionnaire, visual analog scale (VAS), and PPT, evaluated at baseline and after the intervention.

RESULTS

Significant differences were observed in the PPT values at the brachioradialis (P < .05), deltoid (P < .01), and trapezius (P < .001) among the non-chronic and chronic groups, but not in the tibialis anterior muscle (P > .05). Although both control and JPST interventions effectively improved the disabilities of the arm, shoulder, and hand questionnaire score, pain intensity, and PPT values in the upper limb, the outcomes in the JPST group were significantly different from those in the control group.

CONCLUSIONS

Generalized hyperalgesia changes limited to the upper limbs were observed in patients with chronic shoulder pain. JPST has beneficial effects on pain control and functional dysfunction in patients with chronic shoulder pain.

Can we achieve pain stratification in musculoskeletal conditions? Implications for clinical practice

In the last few years there has been an increased appreciation that pain perception in rheumatic and musculoskeletal diseases (RMDs) has several mechanisms which include nociceptive, inflammatory, nociplastic and neuropathic components. Studies in specific patient groups have also demonstrated that the pain experienced by people with specific diagnoses can present with distinctive components over time. For example, the pain observed in rheumatoid arthritis has been widely accepted to be caused by the activation of nociceptors, potentiated by the release of inflammatory mediators, including prostaglandins, leukotrienes and cytokine networks in the joint environment. However, people with RA may also experience nociplastic and neuropathic pain components, particularly when treatments with disease modifying anti-rheumatic drugs (DMARDs) have been implemented and are insufficient to control pain symptoms. In other RMDs, the concept of pain sensitisation or nociplastic pain in driving ongoing pain symptoms e.g. osteoarthritis and fibromyalgia, is becoming increasingly recognised. In this review, we explore the hypothesis that pain has distinct modalities based on clinical, pathophysiological, imaging and genetic factors. The concept of pain stratification in RMD is explored and implications for future management are also discussed.

Nociceptive, neuropathic, or nociplastic low back pain? The low back pain phenotyping (BACPAP) consortium's international and multidisciplinary consensus recommendations

The potential to classify low back pain as being characterised by dominant nociceptive, neuropathic, or nociplastic mechanisms is a clinically relevant issue. Preliminary evidence suggests that these low back pain phenotypes might respond differently to treatments; however, more research must be done before making specific recommendations. Accordingly, the low back pain phenotyping (BACPAP) consortium was established as a group of 36 clinicians and researchers from 13 countries (five continents) and 29 institutions, to apply a modified Nominal Group Technique methodology to develop international and multidisciplinary consensus recommendations to provide guidance for identifying the dominant pain phenotype in patients with low back pain, and potentially adapt pain management strategies. The BACPAP consortium's recommendations are also intended to provide direction for future clinical research by building on the established clinical criteria for neuropathic and nociplastic pain. The BACPAP consortium's consensus recommendations are a necessary early step in the process to determine if personalised pain medicine based on pain phenotypes is feasible for low back pain management. Therefore, these recommendations are not ready to be implemented in clinical practice until additional evidence is generated that is specific to these low back pain phenotypes.

Whole Body Cryostimulation: A New Adjuvant Treatment in Central Sensitization Syndromes? An Expert Opinion

Central sensitisation is defined as a multifactorial etiopathogenetic condition involving an increase in the reactivity of nociceptive neurons and alterations in pain transmission and perception in the central nervous system. Patients may present with widespread chronic pain, fatigue, sleep disturbance, dizziness, psychological (e.g., depression, anxiety, and anger) and social impairment. Pain can be spontaneous in onset and persistence, characterised by an exaggerated response and spread beyond the site of origin, and sometimes triggered by a non-painful stimulus. Whole-body cryostimulation (WBC) could be an adjuvant therapy in the management of this type of pain because of its global anti-inflammatory effect, changes in cytokines and hormone secretion, reduction in nerve conduction velocity, autonomic modulation, and release of neurotransmitters involved in the pain pathway. In several conditions (e.g., fibromyalgia, rheumatoid arthritis, and chronic musculoskeletal pain), WBC affects physical performance, pain perception, and psychological aspects. Given its multiple targets and effects at different organs and levels, WBC appears to be a versatile adjuvant treatment for a wide range of conditions of rehabilitation interest. Further research is needed to fully understand the mechanisms of analgesic effect and potential actions on pain pathways, as well as to study long-term effects and potential uses in other chronic pain conditions.

Immediate effects of visuomotor tracking with the head on cervical sensorimotor function and pain in chronic neck pain patients

BACKGROUND

Working in awkward and sustained postures is, besides psychosocial risk factors, the most reported physical risk factor for neck pain. Accurate proprioception is fundamental to correcting awkward head-to-trunk positions, but impaired proprioceptive performance has been found in patients with chronic neck pain.

OBJECTIVE

The aim was to compare the effectiveness of two different interventions in a workplace set-up on sensorimotor performance and pain sensitivity in people with chronic neck pain.

METHODS

A total of 25 patients with chronic neck pain participated in this double-blind study. Patients were randomly allocated to the visuomotor tracking task group or the video group (watching a massage video, imagining themselves being massaged). The primary outcomes were cervical joint position sense acuity and pressure pain threshold of the cervical spine, evaluated by a blinded assessor.

RESULTS

There were significant time by group interactions for cervical joint position sense acuity (F1;23: 4.38; p= 0.048) and pressure pain threshold (F1;23: 5.78; p= 0.025), with the tracking task group being more accurate in cervical joint position sense testing and less pain sensitive for pressure pain threshold.

CONCLUSIONS

The visuomotor tracking task improves cervical joint position sense acuity and reduces pressure pain threshold immediately after intervention in people with chronic neck pain.

Differences in musculoskeletal dysfunctions and in postural alterations between chronic migraine and chronic tension type headache: A cross-sectional study

OBJECTIVE

The aim of present study is to assess postural alterations and musculoskeletal dysfunctions over all spine in patients with chronic migraine and chronic tension type headache, moreover to highlight the differences between these two forms of primary headache.

METHODS

A Cross sectional study was adopted to evaluate the musculoskeletal profile in patients with chronic migraine and with chronic tension type headache. The Bio photogrammetric evaluation was performed using the postural assessment software PAS/SAPO, while unilateral passive accessory intervertebral motion (PAIMs) were applied for manual examinations of spine segments from C0 to L5 vertebra. The One-way Analysis of Variance (ANOVA) test was used to compare the three groups with the software GraphPad InStat 3.06.

RESULTS

A total of 60 patients were recruited, 20 for chronic tension type group, 20 for chronic migraine group and 20 healthy controls. The most interesting findings was that patients with chronic primary headaches presented postural alterations in all parameters (cranio-vertebral angle and lumbar-pelvic angle) and musculoskeletal dysfunctions in all spine with respect to healthy controls. Finally, the most clinically relevant finding was that no differences were found between chronic migraine and chronic tension type headache concerning the postural alterations nor the musculoskeletal dysfunctions.

CONCLUSION

The sensitization acts as a substrate or consequence of these musculoskeletal dysfunctions in chronic primary headache. Therefore, non-pharmacological treatments targeted in the musculoskeletal system may be a good option in the management of chronic primary headache, especially when these therapies integrate various techniques that involve all spine.

PaiNEd app. Assessing central sensitization in survivors of breast cancer: A reliability study

Introduction

Pain is a common adverse event in survivors of breast cancer (sBCs). As there is no gold standard to assess pain experience predominantly related to central sensitization (CS) symptoms, we designed the PaiNEd app, which includes an algorithm to report whether patients are under predominant CS pain mechanisms.

Objective

We aimed to assess the reliability of the PaiNEd app to estimate whether sBC pain experience is predominantly related to CS symptoms.

Methods

An observational, descriptive reliability design was employed to assess the inter- and intrarater reliability of the PaiNEd app. This app includes an algorithm that considers the number of painful body parts and some questionnaires related to pain, such as the Numeric Pain-Rating Scale, the Brief Pain Inventory, the Tampa Scale for Kinesiophobia, the Pain Catastrophizing Scale, and the Central Sensitization Inventory (CSI).

Results

A total of 21 sBCs with persistent pain were recruited. We observe a general trend of close agreement between the paper-based and app-based formats (ICCs ranged between 0.802 and 0.972; Cronbach's alpha ranged between 0.797 and 0.971). Test-retest reliabilities were moderate to excellent (ICCs ranged between 0.510 and 0.941; Cronbach's alpha ranged between 0.499 and 0.938). The agreement between the categorization of the CS algorithm and the CSI (cut-off point ≥ 40 for CS symptoms) was 95.24%.

Conclusion

The PaiNEd app emerges as a robust tool for evaluating pain experience predominantly related to CS and pain-related symptoms in sBCs. Its demonstrated reliability not only bolsters its utility but also signifies its potential as a valuable asset for healthcare professionals engaged in pain education programs.

Insomnia is associated with symptoms of central sensitization in patients with painful temporomandibular disorders

BACKGROUND

Central sensitization (CS) and temporomandibular disorder (TMD) are both associated with insomnia. Therefore, the authors aimed to investigate whether insomnia was associated with more symptoms of CS in patients with TMD.

METHODS

In 82 volunteers with TMD, insomnia was clinically assessed, allowing sample stratification according to its presence. The Central Sensitization Inventory questionnaire was self-applied to assess the clinical symptoms of CS.

RESULTS

Participants with insomnia had significantly higher mean (SD) scores of CS according to the Central Sensitization Inventory than participants without insomnia (43.10 [12.57] vs 26.59 [13.66]; P = < .001).

CONCLUSIONS

Insomnia was associated with higher scores of CS symptoms in patients with TMD.

PRACTICAL IMPLICATIONS

Insomnia influences TMD as well as its relationship with CS, and, therefore, it is critical to the clinical management of TMD.

The Association Between the Patient Self-Report Survey for the Assessment of Fibromyalgia with Pain Sensitivity and Psychological Factors in Individuals with Musculoskeletal Pain

Purpose

The Patient Self-Report Survey for the Assessment of Fibromyalgia may potentially be a method for subgrouping patients with musculoskeletal pain who have a nociplastic pain presentation. Limited research has explored the convergent validity of this questionnaire against psychophysical measures of pain sensitivity and psychological factors in individuals with musculoskeletal pain. Therefore, the purpose of this study is to examine the strength of the association between total scores on the Patient Self-Report Survey for the Assessment of Fibromyalgia with clinical, pain sensitivity, and psychological factors.

Patients and Methods

As a secondary analysis of a cross-sectional study, participants with shoulder (n = 20) or low back pain (n = 20) completed Quantitative Sensory Testing (QST), pain-related psychological questionnaires, and the Patient Self-Report Survey for the Assessment of Fibromyalgia. A Spearman correlation determined the association between total scores on the Patient Self Report Survey for the Assessment of Fibromyalgia with psychological factors and pain sensitivity behaviorally assessed with QST.

Results

Negative psychological factors demonstrate moderate to strong positive associations with the Patient Self-Report Survey for the Assessment of Fibromyalgia (rho range = 0.36-0.80), suggesting greater negative psychological factors were observed in patients with higher severity of fibromyalgia symptoms. Pain sensitivity factors demonstrated weak to moderate negative associations with The Patient Self-Report Survey for the Assessment of Fibromyalgia (PPT rho range=-0.36- -0.41), suggesting that elevated pain sensitivity was observed in individuals with higher severity of nociplastic pain symptoms.

Conclusion

Collectively, this supports the convergent validity of the Patient Self-Report Survey for the Assessment of Fibromyalgia with psychological and pain sensitivity factors in patients with musculoskeletal pain.

The Analgesic Effect of Transcranial Direct Current Stimulation in Fibromyalgia: A Systematic Review, Meta-Analysis, and Meta-Regression of Potential Influencers of Clinical Effect

BACKGROUND

There is tentative evidence to support the analgesic effect of transcranial direct current stimulation (tDCS) in fibromyalgia (FM), with large variability in the effect size (ES) encountered in different clinical trials. Understanding the source of the variability and exploring how it relates to the clinical results could characterize effective neuromodulation protocols and ultimately guide care in FM pain. The primary objective of this study was to determine the effect of tDCS in FM pain as compared with sham tDCS. The secondary objective was to explore the relationship of methodology, population, and intervention factors and the analgesic effect of tDCS in FM.

MATERIALS AND METHODS

For the primary objective, a systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Randomized clinical trials (RCTs) investigating tDCS as an intervention for FM pain were searched in MEDLINE, Embase, and the Web Of Science. Studies were excluded if they used cross-over designs or if they did not use tDCS as an intervention for pain or did not measure clinical pain. Analysis for the main outcome was performed using a random-effects model. Risk of bias and evidence certainty were assessed for all studies using Cochrane Risk of Bias and Grading of Recommendations Assessment, Development, and Evaluation tools. For the secondary objective, a meta-regression was conducted to explore methodology, population, and intervention factors potentially related to the ES.

RESULTS

Sixteen RCTs were included. Six studies presented a high risk of bias. Significant reduction in pain scores were found for FM (standardized mean difference = 1.22, 95% CI = 0.80-1.65, p < 0.001). Subgroup analysis considering tDCS as a neural target revealed no differences between common neural sites. Meta-regression revealed that the duration of the tDCS protocol in weeks was the only factor associated with the ES, in which protocols that lasted four weeks or longer reported larger ES than shorter protocols.

CONCLUSIONS

Results suggest an analgesic effect of tDCS in FM. tDCS protocols that last four weeks or more may be associated with larger ESs. Definite conclusions are inadequate given the large heterogeneity and limited quality of evidence of the included studies.

Between guidelines and clinical trials: evidence-based advice on the pharmacological management of non-specific chronic low back pain

The pharmacological management of nonspecific chronic low back pain (NCLBP) aims to restore patients' daily activities and improve their quality of life. The management of NCLBP is not well codified and extremely heterogeneous, and residual symptoms are common. Pharmacological management should be considered as co-adjuvant to non-pharmacological therapy, and should be guided by the symptoms reported by the patients. Depending on the individual severity of NCLPB, pharmacological management may range from nonopioid to opioid analgesics. It is important to identify patients with generalized sensory hypersensitivity, who may benefit from dedicated therapy. This article provides an evidence-based overview of the principles of pharmacological management of NCLPB.

Manual Therapy versus Localisation (Tactile, Sensory Training) in Patients with Non-Specific Neck Pain: A Randomised Clinical Pilot Trial

Manual therapy (MT) techniques typically incorporate localised touch on the skin with the application of specific kinetic forces. The contribution of localised touch to the effectiveness of MT techniques has not been evaluated. This study investigated the immediate effects of MT versus localisation training (LT) on pain intensity and range of movement (ROM) for neck pain. In this single-blind randomised controlled trial thirty eligible neck pain volunteers (23 females and 7 males), aged 28.63 ± 12.49 years, were randomly allocated to MT or to a motionless (LT) group. A single three-minute treatment session was delivered to each group's cervico-thoracic area. The LT involved tactile sensory stimulation applied randomly to one out of a nine-block grid. Subjects were asked to identify the number of the square being touched, reflecting a different location on the region of skin. MT involved three-minute anteroposterior (AP) glides and sustained natural apophyseal glides (SNAG) techniques. Pre- and post-intervention pain intensity were assessed using a pressure pain threshold (PPT) algometer and the numeric pain rating scale (NPRS). Neck ROM was recorded with a bubble inclinometer. Improvements in ROM and self-reported pain were recorded in both groups (p < 0.001) without differences in NPRS, ROM or PPT scores between groups (p > 0.05). Tactile sensory training (localisation) was as effective as MT in reducing neck pain, suggesting a component of MT's analgesic effect to be related with the element of localised touch rather than the forces induced during passive movements.

Effect of exercise on chronic neck pain and central sensitization: A protocol for a randomized crossover trial

Exercise-induced hypoalgesia (EIH) has been found to vary widely within individuals with chronic neck pain (NP). Research has suggested that the presence of central sensitization within a subgroup of individuals with chronic NP might be a mediating factor to explain the relationship between exercise and improvements in patient-reported outcomes. Furthermore, recent work has found that lactate might play a role in the development and maintenance of chronic pain. The immediate effect of a single bout of physical exercise on central sensitization in individuals with chronic NP and the relationship between lactate concentration, central sensitization and pain sensitivity are to be investigated. Eighty adult participants with chronic NP will be recruited for this randomized crossover trial. Outcome measures, including temporal summation, conditioned pain modulation, EIH and lactate concentration, will be assessed before and after low- and high-intensity bicycling exercise. The outcomes of this study will provide new insights into the mechanistic effect of exercise on central sensitization in individuals with chronic NP and have the potential to add important information to the current exercise prescription guidelines for individuals with chronic NP. This study has been approved by the Human Research Ethics Committee, The University of Adelaide (H-2022-082) and registered in the Australian New Zealand Clinical Trials Registry (ACTRN12622000642785p).

Soft-Tissue Mobilization and Pain Neuroscience Education for Chronic Nonspecific Low Back Pain with Central Sensitization: A Prospective Randomized Single-Blind Controlled Trial

This study was conducted to demonstrate the therapeutic effect of soft-tissue mobilization (STM) combined with pain neuroscience education (PNE) for patients with chronic nonspecific low back pain with central sensitization. A total of 28 participants were recruited and randomly allocated to either the STM group (SMG) (n = 14) or the STM plus PNE group (BG; blended group) (n = 14). STM was applied twice a week for four weeks, with a total of eight sessions, and PNE was applied within four weeks, for a total of two sessions. The primary outcome was pain intensity, and the secondary outcomes were central sensitization, pressure pain, pain cognition, and disability. Measurements were made at baseline, after the test, and at 2-week and 4-week follow-ups. The BG showed significant improvement in pain intensity (p < 0.001), pressure pain (p < 0.001), disability (p < 0.001), and pain cognition (p < 0.001) compared to the SMG. This study demonstrated that STM plus PNE is more effective for all measured outcomes compared to STM alone. This finding suggests that the combination of PNE and manual therapy has a positive effect on pain, disability index, and psychological factors in the short term.

Accumulation of long-term diseases is associated with musculoskeletal pain dimensions among middle-aged individuals with musculoskeletal pain

BACKGROUND

Long-term diseases often co-occur with musculoskeletal (MSK) pain. In middle-aged individuals with MSK pain, it remains unclear whether an accumulation (two or more) of long-term diseases is associated with MSK pain dimensions, including pain frequency, bothersomeness of pain, pain intensity and number of pain sites.

METHODS

This cross-sectional study included data from the Northern Finland Birth Cohort 1966 collected in 2012-2014 when the participants were 46 years of age. We included participants who reported having MSK pain during the previous year (collected retrospectively) and provided self-reported information related to MSK pain dimensions, long-term diseases and potential confounders (n = 4469). The association between long-term diseases and pain dimensions was modelled by general linear and logistic regression models, with beta (β) coefficients, odds ratios (ORs) and their 95% confidence intervals (CIs) being presented. Unadjusted models were followed by models adjusted for sex, educational level and smoking.

RESULTS

The presence of accumulated long-term diseases was associated with over two-fold higher odds of daily pain (adjusted OR 2.6, 95% CI 2.0-3.4) and significantly higher levels of bothersomeness of pain and pain intensity (adjusted β 1.1, 95% CI 0.9-1.4; adjusted β 1.0, 95% CI 0.8-1.1, respectively), relative to the absence of long-term diseases. Females with accumulated long-term diseases had a stronger relationship to number of pain sites than males. Associations between one long-term disease and pain dimensions were significant but smaller in magnitude.

CONCLUSION

There is a need for a better understanding of the relationships between accumulated long-term diseases and MSK pain.

SIGNIFICANCE

This study on middle-aged individuals with musculoskeletal pain showed that the presence of long-term diseases was clearly associated with pain frequency, bothersomeness of pain, pain intensity and number of pain sites. Compared with no long-term diseases, the association between accumulated (two or more) long-term diseases and pain dimensions was stronger than the association between one long-term disease and pain dimensions.

Effectiveness of Pain Neuroscience Education in Patients with Chronic Musculoskeletal Pain and Central Sensitization: A Systematic Review

OBJECTIVE

To collect the available evidence about the effectiveness of pain neuroscience education (PNE) on pain, disability, and psychosocial factors in patients with chronic musculoskeletal (MSK) pain and central sensitization (CS).

METHODS

A systematic review was conducted. Searches were performed on Pubmed, PEDro, and CINAHL, and only randomized controlled trials (RCTs) enrolling patients ≥18 years of age with chronic MSK pain due to CS were included. No meta-analysis was conducted, and qualitative analysis was realized.

RESULTS

15 RCTs were included. Findings were divided for diagnostic criteria (fibromyalgia-FM, chronic fatigue syndrome-CFS, low back pain-LBP, chronic spinal pain-CSP). PNE has been proposed as a single intervention or associated with other approaches, and different measures were used for the main outcomes considered. Conclusions, practice implication: PNE is effective in improving pain, disability, and psychosocial factors in patients with fibromyalgia, chronic low back pain (CLBP)-especially if associated with other therapeutic approaches-and also in patients with CFS and CSP. Overall, PNE seems to be more effective when proposed in one-to-one oral sessions and associated with reinforcement elements. However, specific eligibility criteria for chronic MSK pain due to CS are still lacking in most RCTs; therefore, for future research, it is mandatory to specify such criteria in primary studies.

Central Sensitization and Chronic Pain Personality Profile: Is There New Evidence? A Case-Control Study

BACKGROUND

Personality traits are relevant for pain perception in persistent pain disorders, although they have not been studied in depth in sensitized and nonsensitized patients with knee osteoarthritis (OA).

OBJECTIVE

To explain and compare the personality profile of patients with OA, with and without central sensitization (CS), and fibromyalgia (FM).

SETTING

Participants were selected at the Rheumatology Department in two major hospitals in Spain.

PARTICIPANTS

Case-control study where the sample consists of 15 patients with OA and CS (OA-CS), 31 OA without CS (OA-noCS), 47 FM, and 22 controls. We used a rigorous and systematic process that ensured the sample strictly fulfilled all the inclusion/exclusion criteria, so the sample is very well delimited.

PRIMARY OUTCOME MEASURES

Personality was assessed by the Temperament and Character Inventory of Cloninger.

RESULTS

The percentile in harm-avoidance dimension for the FM group is higher compared to OA groups and controls. The most frequent temperamental profiles in patients are cautious, methodical, and explosive. Patients with FM are more likely to report larger scores in harm-avoidance, with an increase in logistic regression adjusted odds ratio (ORadj) between 4.2% and 70.2%.

CONCLUSIONS

Harm-avoidance seems to be the most important dimension in personality patients with chronic pain, as previously found. We found no differences between OA groups and between sensitized groups, but there are differences between FM and OA-noCS, so harm-avoidance might be the key to describe personality in patients with CS rather than the presence of prolonged pain, as found in the literature before.

Reconceptualizing Somatic Dysfunction in the Light of a Neuroaesthetic Enactive Paradigm

Background: Palpatory findings are considered a central element of osteopathic practice, especially when associated with a patient's altered regulative functions than with named somatic dysfunctions. Although osteopathic theories for somatic dysfunction could be plausible, the clinical applicability of the concept is debated, especially because it is largely related to simple cause-effect models of osteopathic care. In contrast to a linear kind of diagnosis of a "tissue as a producer of symptoms", this perspective article aims to provide a conceptual and operational framework in which the somatic dysfunction evaluation process is seen as a neuroaesthetic (en)active encounter between osteopath and patient. Subsections relevant to the subject: To summarize all concepts of the hypothesis, the enactive neuroaesthetics principles are proposed as a critical foundation for the osteopathic assessment and treatment of the person, specifically addressing a new paradigm for somatic dysfunction. Conclusions, and future directions: The present perspective article represents a proposition to blend technical rationality informed by neurocognitive and social sciences, and professional artistry clinical experience informed by traditional tenets, to overcome the controversy around somatic dysfunction, rather than dismissing the concept.

Effectiveness of Glenohumeral Joint Mobilization on Range of Motion and Pain in Patients With Rotator Cuff Disorders: A Systematic Review and Meta-Analysis

OBJECTIVE

The purpose of this study was to determine the effectiveness of glenohumeral joint mobilization (JM) on range of motion and pain intensity in patients with rotator cuff (RC) disorders.

METHODS

An electronic search was performed in the MEDLINE, CENTRAL, Embase, PEDro, LILACS, CINAHL, SPORTDiscus, and Web of Science databases. The eligibility criteria for selecting studies included randomized clinical trials that investigated the effect of glenohumeral JM techniques with or without other therapeutic interventions on range of motion, pain intensity, and shoulder function in patients older than 18 years with RC disorders. Two authors independently performed the search, study selection, and data extraction, and assessed risk of bias. Grades of Recommendation Assessment, Development and Evaluation ratings were used to evaluate the quality of evidence in this study.

RESULTS

Twenty-four trials met the eligibility criteria, and 15 studies were included in the quantitative synthesis. At 4 to 6 weeks, for glenohumeral JM with other manual therapy techniques vs other treatments, the mean difference (MD) for shoulder flexion was -3.42° (P = .006), abduction 1.54° (P = .76), external rotation 0.65° (P = .85), and Shoulder and Pain Disability Index score 5.19 points (P = .5), and standard MD for pain intensity was 0.16 (P = .5). At 4 to 5 weeks, for the addition of glenohumeral JM to an exercise program vs exercise program alone, the MD for the visual analog scale was 0.13 cm (P = .51) and the Shoulder and Pain Disability Index score was -4.04 points (P = .01).

CONCLUSION

Compared with other treatments or an exercise program alone, the addition of glenohumeral JM with or without other manual therapy techniques does not provide significant clinical benefit with respect to shoulder function, range of motion, or pain intensity in patients with RC disorders. The quality of evidence was very low to high according to Grades of Recommendation Assessment, Development and Evaluation ratings.

Towards precision pain medicine for pain after cancer: the Cancer Pain Phenotyping Network multidisciplinary international guidelines for pain phenotyping using nociplastic pain criteria

Pain after cancer remains underestimated and undertreated. Precision medicine is a recent concept that refers to the ability to classify patients into subgroups that differ in their susceptibility to, biology, or prognosis of a particular disease, or in their response to a specific treatment, and thus to tailor treatment to the individual patient characteristics. Applying this to pain after cancer, the ability to classify post-cancer pain into the three major pain phenotypes (i.e. nociceptive, neuropathic, and nociplastic pain) and tailor pain treatment accordingly, is an emerging issue. This is especially relevant because available evidence suggests that nociplastic pain is present in an important subgroup of those patients experiencing post-cancer pain. The 2021 International Association for the Study of Pain (IASP) clinical criteria and grading system for nociplastic pain account for the need to identify and correctly classify patients according to the pain phenotype early in their treatment. These criteria are an important step towards precision pain medicine with great potential for the field of clinical oncology. Within this framework, the Cancer Pain Phenotyping (CANPPHE) Network, an international and interdisciplinary group of oncology clinicians and researchers from seven countries, applied the 2021 IASP clinical criteria for nociplastic pain to the growing population of those experiencing post-cancer pain. A manual is provided to allow clinicians to differentiate between predominant nociceptive, neuropathic, or nociplastic pain after cancer. A seven-step diagnostic approach is presented and illustrated using cases to enhance understanding and encourage effective implementation of this approach in clinical practice.

Global trends in research on cervicogenic headache: a bibliometric analysis

Background

There has been a marked increase in cervicogenic headaches in recent years, significantly affecting sufferers' daily lives and work. While several treatments exist for this type of headache, their long-term effects could be improved, and additional data from large clinical samples are needed. This study aims to systematically examine the current state of research in cervicogenic headaches through a bibliometric analysis, identify areas of current interest, and provide insight into potential future research directions.

Methods

This article examines research trends in the field of cervicogenic headache through a bibliometric analysis of scholarly articles in the field of cervicogenic headache over the past four decades. The bibliometric analysis method employed included searching the Web of Science database using topics related to cervicogenic headaches. Inclusion criteria were limited to articles and review papers on cervicogenic headaches published between 1982 and 2022. The retrieved dataset was then analyzed using R software and VOSviewer to identify the major research areas, countries and institutions, the most influential authors, journals and keywords, co-citations in the literature, and co-authorship networks.

Results

This study analyzed 866 articles published between 1982 and 2022, involving 2,688 authors and generating 1,499 unique author keywords. Neuroscience and neurology were the primary focus, with participation from 47 countries, primarily led by the United States, which has the most published articles (n = 207), connections (n = 29), and citations (n = 5,238). In the cervicogenic headache study, which involved 602 institutions, the University of Queensland received the most significant number of citations (n = 876), and Cephalalgia was the journal with the most published articles and received the most local citations (n = 82) and highest growth (n = 36). Two hundred sixty-nine journals have published articles on cervicogenic headaches. Among researchers studying cervicogenic headache, Sjaastad O had the most published articles (n = 51) and citations (n = 22). The most commonly occurring keyword was "cervicogenic headache." Except for the fourth most impactful paper, as determined by the Local Citation Score, which analyzed clinical treatments, all the top documents emphasized investigating the diagnostic mechanisms of cervicogenic headache. The most commonly occurring keyword was "cervicogenic headache."

Conclusion

This study used bibliometric analysis to provide a comprehensive overview of the current research on cervicogenic headaches. The findings highlight several areas of research interest, including the need for further investigation into the diagnosis and treatment of cervicogenic headaches, the impact of lifestyle factors on cervicogenic headaches, and the development of new interventions to improve patient outcomes. By identifying these gaps in the literature, this study provides a foundation for guiding future research to improve the diagnosis and treatment of cervicogenic headaches.

Characteristics and Outcomes of Patients Receiving Physical Therapy for Low Back Pain with a Nociplastic Pain Presentation: A Secondary Analysis

Introduction

Individuals with low back pain (LBP) may be classified based on mechanistic descriptors, such as a nociplastic pain presentation (NPP). The purpose of this secondary analysis was to examine the frequency and characteristics of patients with a NPP referred to physical therapy with LBP. Additionally, we characterized patients with LBP meeting the criteria for NPP by demographic, clinical, psychological, and pain sensitivity variables. Finally, we examined short- and long-term clinical outcomes in patients with a NPP compared to those without a NPP.

Materials and Methods

Patients referred to physical therapy for LBP completed the Patient Self-report Survey for the Assessment of Fibromyalgia. Participants were categorized as "LBP with NPP" or "LBP without NPP" based on the threshold established in this measure. A rank sum test examined for differences in pain-related psychological factors and pressure-pain threshold between groups. Next, a Friedman test examined if LBP intensity and disability trajectories differed by groups at one and six months after initiation of physical therapy.

Results

22.2% of patients referred to physical therapy for LBP met the criteria for a NPP. Patients with a NPP reported significantly greater disability, pain catastrophizing, depression, anxiety, and somatization compared to individuals without a NPP (p < 0.05). Pressure-pain threshold did not differ between groups (p > 0.05). Individuals with LBP with a NPP demonstrated nonsignificant, small to medium reductions in pain and disability at one and six months. Individuals experiencing LBP without a NPP demonstrated significant reductions in pain and disability in the short- and long term.

Conclusion

Patients with LBP with a NPP displayed greater negative pain-related psychological factors but similar pain sensitivity compared to LBP without NPP.

Understanding how patients' pain beliefs influence chronic low back pain management in Ghana: a grounded theory approach

INTRODUCTION

Chronic low back pain (CLBP) is associated with negative consequences in high and low/middle-income countries. Pain beliefs are important psychosocial factors that affect the occurrence and progression of CLBP and may be influenced by the sociocultural context and interactions with healthcare professionals (HCPs). The pain beliefs of Ghanaian patients with CLBP are unknown and the factors influencing pain beliefs in African contexts are unclear.

OBJECTIVES

To explore the pain beliefs of Ghanaian patients with CLBP, how they influence CLBP management/coping and to identify the mechanisms influencing them.

DESIGN

Qualitative study using individual semistructured face-to-face interviews, situated within Straussian grounded theory principles and critical realist philosophy.

PARTICIPANTS

Thirty patients with CLBP accessing physiotherapy at two teaching hospitals in Ghana.

RESULTS

Participants suggested dominant biomedical/mechanical beliefs (related to CLBP causes, posture and activity, and the belief of an endpoint/cure for CLBP). Maladaptive beliefs and practices, in particular fear-avoidance beliefs, and dependence on passive management and coping, were common among participants. These beliefs and practices were mostly influenced by HCPs and sociocultural expectations/norms. Although spirituality, pacing activity and prescribed exercises were commonly mentioned by participants, other active strategies and positive beliefs were expressed by a few participants and influenced by patients' themselves. Limited physiotherapy involvement, knowledge and awareness were also reported by participants, and this appeared to be influenced by the limited physiotherapy visibility in Ghana.

CONCLUSION

Participants' narratives suggested the dominant influence of HCPs and the sociocultural environment on their biomedical/mechanical beliefs. These facilitated maladaptive beliefs and adoption of passive coping and management practices. Therefore, incorporation of more positive beliefs and holistic/active strategies by Ghanaian patients and HCPs may be beneficial. Furthermore, patient empowerment and health literacy opportunities to address unhelpful CLBP/sociocultural beliefs and equip patients with management options for CLBP could be beneficial.

Eveningness is associated with persistent multisite musculoskeletal pain: a 15-year follow-up study of Northern Finns

Chronotype, a phenotype representing a person's 24-hour circadian rhythm, has been increasingly acknowledged as playing a role in musculoskeletal (MSK) pain. Most prior research on chronotype and MSK pain have been based on cross-sectional data, and no study has explored multisite MSK pain (two or more pain locations) as the outcome. We drew the study sample from the 31- and 46-year data collections (baseline and follow-up, respectively) of the Northern Finland Birth Cohort 1966 and collected self-reported data on chronotype at follow-up (morning [M]-type, intermediate [I]-type, and evening [E]-type) and longitudinal multisite MSK pain trajectories (n=3,294). Multinomial logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) in multisite MSK pain trajectories between the chronotypes. We conducted additional sensitivity analyses that 1) accounted for several confounders, and 2) examined the potential moderating role of sex, mental distress, and sleep disturbance status in the chronotype-multisite MSK pain associations. The E-types had two-and-a-half-times higher odds of multisite MSK pain at baseline and follow-up (OR 2.47, 95% CI 1.84-3.32) than the M-types. Having severe mental distress or poor sleep at baseline and follow-up, or sex did not change the strength of this association. Our examination of this longitudinal birth cohort study suggested that evening types, in comparison to morning types, are more likely to experience multisite MSK pain between ages 31 and 46 years. Chronotype should be recognized as a predictor of multisite pain and thus taken into account in the evaluation of a patient's risk for multisite pain. Perspective: This longitudinal study shows that evening types, compared to morning types, have higher odds of experiencing multisite MSK pain between ages 31 and 46 years. Chronotype should be considered while evaluating MSK patient's risk for persistent multisite pain symptoms.

Algometry for the assessment of central sensitisation to pain in fibromyalgia patients: a systematic review

INTRODUCTION

The pathophysiology of fibromyalgia (FM) is related to central sensitisation (CS) to pain. Algometry allows assessing CS based on dynamic evoked pain. However, current algometrýs protocols require optimising, unifying and updating.

OBJECTIVES

1) identify the dynamic pain measures used most frequently to effectively assess CS processes in FM, and 2) consider the future of the algometry assessing CS in these patients.

METHODS

Cochrane Collaboration guidelines and PRISMA statements were followed. The protocol was registered in PROSPERO database (ID: CRD42021270135). The selected articles were evaluated using the Cochrane risk of bias (ROB) assessment tool. The PubMed, Scopus, and Web of Science databases were searched.

RESULTS

Thirty-four studies were selected, including measures such as temporal summation of pain (TSP), aftersensations (AS), spatial summation of pain (SSP), the noxious flexion reflex (NFR) threshold, conditioned pain modulation (CPM), cutaneous silent period (CuSP), and slowly repeated evoked pain (SREP); and evoked pain combined with neuroimaging. Each measure offered various advantages and limitations. According to ROB, 28 studies were of low quality, 3 of moderate quality, and 3 of high quality.

CONCLUSIONS

Several pain indicators have been demonstrated to successfully examine CS involvement in FM in the last years. Algometry, especially when it involves diverse body sites and tissues, might provide further insight into (1) the evaluation of psychological factors known to influence pain experience, (2) new dynamic pain indicators, and (3) the simultaneous use of certain neuroimaging techniques. Further research clarifying the mechanisms underlying some of these measures, and homogenisation and optimisation of the algometrýs protocols, are needed. KEY MESSAGESAlgometry allows for assessing Central Sensitisation by applying dynamic evoked pain.The future of algometry could relapse in its combination with neuroimaging.Recently-emerged pain indicators should be considered for algometrýs new protocols.

Cross cultural adaptation, validity, and reliability of Central Sensitization Inventory in Arabic language

PURPOSE

The Central Sensitization Inventory (CSI) is a tool that aid in identifying symptoms associated with nociplastic pain. The aim of this study is to adapt CSI to Arabic language, and to examine its psychometric properties.

METHODS

Adaptation process followed recommended guidelines. Participants with self-reported chronic pain completed a web-based survey. The internal consistency was calculated. Test-retest reliability was examined by allowing 7-9 day gap between two rounds of measurements. Convergent validity was examined by measuring the correlation with Pain Catastrophizing Scale (PCS), EQ-VAS, and EQ-5D-3L. Discriminant validity was examined by testing four priori hypotheses. Factor analysis with principal components extraction was conducted.

RESULTS

CSI-Arabic (CSI-Ar) was successfully produced. Its internal consistency and test-retest reliability were excellent (Cronbach's α = 0.88 and ICC_2,1=0.94). The standard error of measurement and minimal detectable change 95% were 3.45 and 9.57, respectively. CSI total score correlation with PCS, EQ-5D-3L, and EQ-VAS was moderate. The results lend support to the four hypothesis related to discriminant validity. Factor analysis revealed a four-factor structure of CSI-Ar.

CONCLUSIONS

CSI-Ar showed an internal consistency, test-retest reliability, and validity that are comparable to similar studies. The results support the use of CSI-Ar in assessing chronic pain in Arabic-speaking population.Implications for rehabilitationCentral sensitization (CS) mechanisms are thought to contribute to chronic pain.Identifying the presence of CS would personalize management.The Central Sensitization Inventory (CSI) is a valid and reliable tool to aid in identifying symptoms associated with CS.The Arabic version of the CSI is valid and reliable to use in Arabic speaking patients suffering from chronic pain.

Understanding the clinical profile of patients with frozen shoulder: a longitudinal multicentre observational study

INTRODUCTION

There is a large diversity in the clinical presentation of frozen shoulder (FS) and the clinical outcome is not always satisfactory. The aim of the current study was to examine to what extent range of motion (ROM) limitation, metabolic factors (diabetes mellitus and thyroid disorders), autonomic symptoms and pain sensitivity may contribute to the prognosis in terms of shoulder pain and disability and quality of life in patients with FS.

METHODS

Patients with stage 1 or 2 FS were longitudinally followed-up during 9 months after baseline assessment. They completed six questionnaires and underwent quantitative sensory testing (pressure pain thresholds, temporal summation and conditioned pain modulation) and ROM assessment.

RESULTS

One hundred and forty-nine patients with FS were initially recruited and 121 completed at least one follow-up measurement. Shoulder pain and disability improved over time and diabetes mellitus was found to be a prognostic factor for final outcome. Several domains of quality of life also improved over time and external rotation ROM, diabetes mellitus, thyroid disorder and autonomic symptoms were found to be prognostic factors for final outcome. These prognostic factors explained 2.5%-6.3% of the final outcome of shoulder pain and disability and quality of life.

DISCUSSION AND CONCLUSION

In patients with FS, prognostic variables were able to predict different outcomes, indicating that outcomes in this population can be variable-dependent. Other variables not explored in this study might contribute to the prognosis of patients with FS, which should be investigated in future research. In clinical practice, baseline assessment of prognostic factors and focusing on a more holistic approach might be useful to inform healthcare practitioners about progression of patients with FS during a 9-month period.

Validity of the Central Sensitization Inventory compared with traditional measures of disease severity in fibromyalgia

OBJECTIVE

The goal of this study was to explore additional evidence of convergent and discriminant validity of the Central Sensitization Inventory (CSI) in a large sample of subjects with fibromyalgia (FM).

METHODS

Patients were consecutively enrolled for a cross-sectional assessment comprehensive of three FM-specific measures (the revised Fibromyalgia Impact Questionnaire [FIQR], the modified Fibromyalgia Assessment Status [modFAS], and the Polysymptomatic Distress Scale [PDS]) and of CSI. To test the convergent validity, the Spearman's rho was used to measure the degree of correlation between the variables CSI and the FM-specific measures. To assess discriminant validity, CSI scores were grouped according to FIQR disease severity states, and differences between these groups studied with the Kruskal-Wallis test. Interpretative cutoffs were established with the interquartile reconciliation approach.

RESULTS

The study included 562 FM patients, 199 (35.4%) were classified as having central sensitization syndrome (CSI ≥40). CSI was largely correlated with modFAS (ρ = 0.580; p < 0.0001), FIQR (ρ = 0.542; p < 0.0001), and PDS (ρ = 0.518; p < 0.0001). The differences between the CSI scores in accordance with the FIQR were significant (p < 0.000001). CSI cutoffs proposed for FM: 21 between remission and mild severity, 30 between mild and moderate severity, 37 between moderate and severe disease, and 51 between severe and very severe disease.

CONCLUSION

The current study successfully showed additional evidence of the convergent and discriminant validity of the CSI in FM patients.

Evidence-Based Clinical Guidelines from the American Society of Pain and Neuroscience for the Use of Implantable Peripheral Nerve Stimulation in the Treatment of Chronic Pain

The objective of this peripheral nerve stimulation consensus guideline is to add to the current family of consensus practice guidelines and incorporate a systematic review process. The published literature was searched from relevant electronic databases, including PubMed, Scopus, Cochrane Central Register of Controlled Trials, and Web of Science from database inception to March 29, 2021. Inclusion criteria encompassed studies that described peripheral nerve stimulation in patients in terms of clinical outcomes for various pain conditions, physiological mechanism of action, surgical technique, technique of placement, and adverse events. Twenty randomized controlled trials and 33 prospective observational studies were included in the systematic review process. There is Level I evidence supporting the efficacy of PNS for treatment of chronic migraine headaches via occipital nerve stimulation; chronic hemiplegic shoulder pain via stimulation of nerves innervating the trapezius, supraspinatus, and deltoid muscles; failed back surgery syndrome via subcutaneous peripheral field stimulation; and lower extremity neuropathic and lower extremity post-amputation pain. Evidence from current Level I studies combined with newer technologies facilitating less invasive and easier electrode placement make peripheral nerve stimulation an attractive alternative for managing patients with complex pain disorders. Peripheral nerve stimulation should be used judiciously as an adjunct for chronic and acute postoperative pain following adequate patient screening and positive diagnostic nerve block or stimulation trial.

Association Between Pain Catastrophizing and Central Sensitization Among Patients With Severe Knee Osteoarthritis Awaiting Primary Total Knee Arthroplasty

Total knee arthroplasty (TKA) is among the most successful types of surgery for the treatment of knee osteoarthritis (OA). However, nearly 20% of patients report unexpected pain after surgery. Recently, some studies have proposed that pain after TKA is related to pain catastrophizing (PC) and central sensitization (CS). However, there is no study comparing PC and CS for the same patient with knee OA requiring TKA. Thus, the goal of this study was to confirm the association between PC and CS among patients with knee OA awaiting primary TKA. This study was conducted with the clinical data of 153 patients collected between July 2019 and February 2021. Both PC and CS were evaluated with the Pain Catastrophizing Scale (PCS) and the Central Sensitizing Inventory (CSI). Patients with PCS scores higher than 30 were classified as high-level catastrophizing. Patients with CSI scores higher than 40 were classified as central sensitized. The distribution of PC and CS levels was confirmed, and the correlation between PC and CS was analyzed. A significant correlation was found between PCS and CSI scores, with Pearson's correlation coefficient of 0.606. Participants with high-level catastrophizing were 2.07 times more likely to belong to the central sensitized group compared with those who did not show high-level catastrophizing. Participants in the central sensitized group were 3.02 times more likely to belong to the high-level catastrophizing group than those who were not central sensitized. In conclusion, many patients with knee OA awaiting primary TKA had high-level catastrophizing, and a significant association was found between PC and CS. [Orthopedics. 2022;45(4):197-202.].

Tendinopathies and Pain Sensitisation: A Meta-Analysis with Meta-Regression

The presence of pain sensitisation has been documented and reported as being a possible cause of treatment failure and pain chronicity in several musculoskeletal conditions, such as tendinopathies. The aim of the present study is to analyse existing evidence on pain sensitisation in tendinopathies comparing the local and distant pain thresholds of healthy and affected subjects with distinct analysis for different tendinopathies. PubMed, Cochrane Central Register, Scopus, and Web Of Science were systematically searched after registration on PROSPERO (CRD42020164124). Level I to level IV studies evaluating the presence of pain sensitisation in patients with symptomatic tendinopathies, documented through a validated method, were included. A meta-analysis was performed to compare local, contralateral, and distant pain thresholds between patients and healthy controls with sub-analyses for different tendinopathies. Meta-regressions were conducted to evaluate the influence of age, activity level, and duration of symptoms on results. Thirty-four studies out of 2868 were included. The overall meta-analysis of local pressure pain thresholds (PPT) documented an increased sensitivity in affected subjects (p < 0.001). The analyses on contralateral PPTs (p < 0.001) and distant PPTs (p = 0.009) documented increased sensitivity in the affected group. The results of the sub-analyses on different tendinopathies were conflicting, except for those on lateral epicondylalgia. Patients’ activity level (p = 0.02) and age (p = 0.05) significantly influenced local PPT results. Tendinopathies are characterized by pain sensitisation, but, while features of both central and peripheral sensitisation can be constantly detected in lateral epicondylalgia, results on other tendinopathies were more conflicting. Patients’ characteristics are possible confounders that should be taken into account when addressing pain sensitisation.

A protocol for a randomized trial on pain neuroscience education vs. routine physical therapy in people with chronic neck pain

The aim of this study is to investigate the effects of combining routine physical therapy with pain neuroscience education (PNE) on psychosocial factors, physical performance, and the experienced pain in patients with chronic neck pain (CNP). This study is a double-blind randomized clinical trial in which patients will be randomly allocated to two groups, routine physical therapy with and without PNE. Patients will be assessed at the baseline, post intervention, and three months later. The results of this research will be used to establish effectiveness of treatment strategies for CNP. Due to the rigorous scientific methods used in this research, the suggested interventions would be clinically applicable in the health care systems.

Combination of Two Manipulative Techniques for the Treatment of Cervicogenic Dizziness: A Randomized Controlled Trial

Cervicogenic dizziness is clinically associated with upper cervical spine dysfunctions. It seems that manual therapy decreases the intensity of dizziness in these subjects, but what happens to pain measured by pressure pain threshold (PPT) has not been studied. Purpose: analyze the short-term effects of combination two manipulation techniques protocol in worst dizziness intensity (wVAS), dizziness and cervical disability, upper cervical spine mobility and mechanosensivity of cervical tissue. Methods: Assessor-blinded randomized controlled trial was developed. A total of 40 patients with cervicogenic dizziness were randomly divided into two groups. The experimental group received three treatments consisting of a functional massage and a manipulation technique, and compared with a control group. The wVAS, dizziness handicap inventory (DHI), neck disability index (NDI), UCS mobility, and PPTs were measured. Measurements were made at the baseline, first follow-up 48 h after intervention and second follow-up 1 month after the intervention. Results: at second follow-up wVAS (p < 0.001), NDI (p < 0.001), DHI (p < 0.001), and upper right trapezius (p < 0.022) and right suboccipital (p < 0.043) PPTs showed a difference between groups in favor of the experimental group. Conclusions: apparently, the proposed intervention protocol decreases the intensity of dizziness and the mechanosensitivity of the cervical tissue and improves the feeling of disability due to neck pain and dizziness.

Effect of central sensitization inventory on the number of painful sites and pain severity in a Japanese regional population cohort

BACKGROUND

To investigate the association between the central sensitization inventory (CSI), a screening tool for central sensitization, and the number of painful sites and the severity of pain in locomotive organs in an epidemiological study in the elderly.

METHODS

A total of 379 individuals who underwent musculoskeletal disease screening were enrolled in this study. The CSI was used to assess symptoms of central sensitization. The number and location of painful sites and the severity of pain were evaluated using pain mapping and a numerical rating scale (NRS) at 37 sites. We investigated the association between the number of painful sites and CSI score, and the association between the severity of low back pain or knee pain and CSI score.

RESULTS

There was a positive correlation between CSI score and the number of painful sites. The CSI score was significantly higher in those with significant low back pain than in those without pain, and the high-CSI group tended to have a greater number of painful sites. Comparison of CSI scores between participants with low back pain alone and those with low back pain and posterior lower leg pain showed that the latter group had a significantly higher CSI score than the former group. The CSI score in participants with radiographic evidence of knee osteoarthritis was significantly higher in those with knee pain than in those without pain.

CONCLUSIONS

The results of this study suggest that participants with significant low back pain and a higher number of painful sites are more susceptible to the influence of central sensitization. In addition, CSI score was higher in participants with low back pain and posterior lower leg pain than in those with low back pain alone, suggesting that the spread of pain may be due to central sensitization.

Exploring pain mechanisms in hypermobile Ehlers-Danlos syndrome: a case-control study

BACKGROUND

The hypermobile type of Ehlers-Danlos syndrome (hEDS) is a heritable connective tissue disorder, associated with joint hypermobility and prominent chronic pain. Because experimental pain testing in hEDS is scarce, the underlying mechanisms are still poorly understood.

OBJECTIVE

The present study assesses endogenous pain facilitation and pain inhibition in hEDS, using a protocol for temporal summation of pain (TSP), conditioned pain modulation (CPM), and exercise-induced hypoalgesia (EIH).

METHODS

Twenty women with hEDS and 20 age-matched healthy controls participated. After evaluating thermal and mechanical pain thresholds (PPT), TSP was assessed using 10 repetitive painful pressure stimuli. CPM was provoked using pressure as the test stimulus and hand immersion in hot water (46°) as the conditioning stimulus. EIH was assessed after a submaximal cycling protocol.

RESULTS

The hEDS group demonstrated reduced PPTs and showed significantly more TSP after repeated painful stimuli than the control group. The increase in PPTs caused by the submaximal cycling protocol (EIH) did not reach statistical significance in the hEDS group. Furthermore, in comparison to the healthy control group, the hEDS group demonstrated significantly less EIH at the quadriceps test location. At the trapezius, EIH did not significantly differ between groups. No significant differences were found between the hEDS group and control group in the CPM response.

CONCLUSION

The results demonstrate increased TSP in hEDS, suggesting increased central pain facilitation. EIH should be studied more extensively, but may be disturbed when evaluated in working muscles. The CPM results are inconclusive and require more research.

Central sensitization and adult attention deficit hyperactivity disorder in medical students with chronic back pain: a cross-sectional study

Background

Chronic back pain is a common health complaint among university students. A subset of chronic back pain patients suffer from increased pain sensitivity, a process termed central sensitization. Chronic pain is also associated with cognitive dysfunction, involving attention, memory, and learning. Those are key features of adult attention deficit hyperactivity disorder. This study aimed to assess the associations between adult attention deficit hyperactivity disorder and central sensitization in students with chronic back pain.

Results

Two hundred twenty-seven students completed the survey, and 90 (39.6%) had back pain for more than 3 months. Students with back pain had significantly higher central sensitization (P<0.01) and higher attention deficit scores (P=0.05). Significant positive correlations were found between scores of the two questionnaires (r= 0.55, P<0.01). Regression analysis adjusted for age and gender showed that higher attention deficit scores were associated with back pain (odd’s ratio:1.025, P=0.05). The odd’s ratio was attenuated after adding central sensitization to the model (odd’s ratio: 0.99, P=0.70).

Conclusions

The findings of this study suggest that attention deficit hyperactivity disorder is associated with elevated central sensitization in patients with chronic back pain. Our results support the hypothesis that central sensitization mediates the effect of attention deficit on back pain.