Transitioning from Acute to Chronic Pain: An Examination of Different Trajectories of Low-Back Pain

Development, validation and use of custom software for the analysis of pain trajectories

In chronic musculoskeletal conditions, the prognosis tends to be more informative than the diagnosis for the future course of the disease. Many studies have identified clusters of patients who seemingly share similar pain trajectories. In a dataset of low back pain (LBP) patients, pain trajectories have been identified, and distinct trajectory types have been defined, making it possible to create pattern recognition software that can classify patients into respective pain trajectories reflecting their condition. It has been suggested that the classification of pain trajectories may create clinically meaningful subgroups of patients in an otherwise heterogeneous population of patients with LBP. A software tool was created that combined the ability to recognise the pain trajectory of patients with a system that could create subgroups of patients based on their characteristics. This tool is primarily meant for researchers to analyse trends in large heterogeneous datasets without large losses of data. Prospective analysis of pain trajectories is not directly helpful for clinicians. However, the tool might aid in the identification of patient characteristics which have predictive capabilities of the most likely trajectory a patient might experience in the future. This will help clinicians to tailor their advice and treatment for a specific patient.

Disability and pain after anterior cervical decompression and fusion: A group-based trajectory analysis

OBJECTIVES

This study aimed to identify the clusters of patients with different developmental trajectories of pain and disability after anterior cervical decompression and fusion (ACDF).

METHODS

Group-based trajectory analysis among 318 patients undergoing the ACDF.

RESULTS

Three developmental trajectories of disability were identified: "Steadily good functioning," "Improved functioning," and "Steadily poor functioning." Three developmental trajectories of neck pain were identified: "Worsened pain," "Pain relief," and "Steadily severe pain." Two developmental trajectories of arm pain were identified: "Decreased arm pain" and "Severe arm pain with only short-term relief." No associations were found between sex, preoperative pain duration, or body weight and probability to be classified into a particular disability trajectory group. Female sex (relative risk ratio (RRR) 1.78) and longer history of preoperative pain (RRR 2.31-2.68) increased the probability to be classified into a group with steadily severe neck pain. Longer history of preoperative pain increased the probability to be classified into group with severe arm pain with only short-term pain relief (RRR 2.68).

CONCLUSION

After the ACDF, dissimilar developmental trajectories of pain and disability were identified between the patient clusters. While sex, preoperative pain duration, and body weight were not associated with differences in improvement in disability level, female sex and longer duration of preoperative pain were correlated with more severe neck and arm pain after surgery.

The course of acute low back pain: a community-based inception cohort study

Introduction

Acute low back pain (LBP) is increasingly recognized for its potential recurrent nature and long-term implications.

Objectives

This community-based inception cohort study aimed to delineate trajectories of acute LBP over one year and investigate associated biopsychosocial variables.

Methods

One hundred seventy-six participants with acute LBP were monitored at 5 follow-up time points over 52 weeks. Pain trajectories were identified using a latent class linear mixed model, and their associations with baseline biopsychosocial factors were evaluated through multinomial logistic regression.

Results

Four distinct LBP trajectories were discerned: "mild/moderate fluctuating pain" (54.0%), "delayed recovery by week 52" (6.2%), "persistent moderate pain" (33.0%), and "moderate/severe fluctuating pain" (6.8%). Increased baseline pain intensity and history of LBP episodes were significantly linked with less favorable trajectories. Contrary to expectations, psychological variables like stress, anxiety, and depression did not significantly associate with unfavorable trajectories.

Discussion

This study underscores the heterogeneity of acute LBP's course over a year, challenging the conventionally benign perception of the condition. Recognizing these distinct trajectories might enable more tailored, effective clinical interventions for LBP patients. The small sample size of certain trajectories may influence the generalizability of the results.

Conclusion

Acute LBP can manifest in different trajectories, with nearly half of the participants experiencing less favorable trajectories. Baseline pain intensity and previous episodes of LBP emerged as key factors, whereas psychological variables had no discernible influence. Recognition of these trajectories may be necessary for improved patient management and targeted interventions.

The role of the physiotherapist in concussion

In the last decade, concussion research has exploded in multiple fields of scientific research. This has helped to clarify what causes, influences, and perpetuates human concussion, and displays the integral role physiotherapists play in concussion management. In this article we discuss the latest research relevant to the key role of physiotherapy in concussion management. A narrative review of the literature on concussion was conducted. The current review analyses how concussion has influenced physiotherapy in several categories: assessment, treatment, management, research rigour and building the profile of the profession. Scientific concussion research has largely converged in support of the role of physiotherapists utilising specific components including: (1) autonomic, (2) cervicogenic, (3) vestibulo-ocular and (4) psychological approaches to management. Latest research supports the critical role of physiotherapy in concussion care in the assessment, management, and prevention of concussion with scope for further interdisciplinary collaborations.

Clinical implications

Concussion is complex. A basic mental health, Vestibular Ocular Motor Screening (VOMS) and four key components relating to concussion management (autonomic, cervicogenic, vestibular oculomotor, and psychological approaches to management) should be included in the undergraduate and postgraduate curriculum. This will aid clinical physiotherapists to support their patients. A call to advance more intradisciplinary physiotherapy teamwork should be encouraged as valuable knowledge sharing is potentially lost within the framework of 'specialisation'. If needed, the skills of a greater interdisciplinary team are imperative to facilitate patient management and recovery from this multi-faceted injury.

Influences of Cognitive Function and Depressive Symptoms on Pain Trajectories During the First Year Following Hip Fracture Surgery: A Prospective Cohort Study

OBJECTIVES

The purposes of this study were to explore trajectories for patterns of postoperative pain intensity during the first year following hip fracture surgery and the relationships between pain trajectory groups, cognitive impairment, and depressive symptoms.

DESIGN

A prospective cohort correlational study.

SETTING AND PARTICIPANTS

A total of 325 patients aged 60 years or older who had received hip fracture surgery at a 3000-bed medical center in northern Taiwan from September 2012 to March 2020.

METHODS

Data were collected before hospital discharge and at 1, 3, 6, and 12 months postdischarge. Pain intensity was measured using a numeric rating scale; cognitive function was measured with the Taiwan version of the Mini-Mental State Examination; and depressive symptoms were measured by the Geriatric Depression Scale-Short Form. Patients with similar postoperative pain trajectories were categorized into groups and compared with group-based trajectory modeling. Cognitive impairment and depressive symptoms associated with each group were identified by logistic regression.

RESULTS

Three different pain trajectory groups were identified: drastic decline-minimum pain (47.7%), gentle decline-mild pain (45.5%), and slight decline-moderate pain (6.8%). Patients with cognitive impairment [odds ratio (OR) 11.01, 95% CI 2.99-10.51] and at risk for depression (OR 49.09, 95% CI 10.46-230.30) were more likely to be in the moderate pain group than the minimum pain group. Patients with cognitive impairment (OR 2.07, 95% CI 1.25-3.42) were more likely to be in the mild pain group than the minimum pain group. Patients at risk for depression (OR 9.68, 95% CI 3.16-29.63) were more likely to be in the moderate pain group than the mild pain group.

CONCLUSIONS AND IMPLICATIONS

Identifying postoperative pain trajectories can provide insight into the most appropriate pain management for older persons following hip fracture surgery. Attention should focus on assessments for cognitive impairment and risk of depression to prevent persistent postoperative pain. Future studies of older patients with clinically diagnosed cognitive impairment and depression are suggested.

Racial and Ethnic Disparities in the Incidence of High-Impact Chronic Pain Among Primary Care Patients with Acute Low Back Pain: A Cohort Study

OBJECTIVE

We assessed whether race or ethnicity was associated with the incidence of high-impact chronic low back pain (cLBP) among adults consulting a primary care provider for acute low back pain (aLBP).

METHODS

In this secondary analysis of a prospective cohort study, patients with aLBP were identified through screening at seventy-seven primary care practices from four geographic regions. Incidence of high-impact cLBP was defined as the subset of patients with cLBP and at least moderate disability on Oswestry Disability Index [ODI >30]) at 6 months. General linear mixed models provided adjusted estimates of association between race/ethnicity and high-impact cLBP.

RESULTS

We identified 9,088 patients with aLBP (81.3% White; 14.3% Black; 4.4% Hispanic). Black/Hispanic patients compared to White patients, were younger and more likely to be female, obese, have Medicaid insurance, worse disability on ODI, and were at higher risk of persistent disability on STarT Back Tool (all P < .0001). At 6 months, more Black and Hispanic patients reported high-impact cLBP (30% and 25%, respectively) compared to White patients (15%, P < .0001, n = 5,035). After adjusting for measured differences in socioeconomic and back-related risk factors, compared to White patients, the increased odds of high-impact cLBP remained statistically significant for Black but not Hispanic patients (adjusted odds ration [aOR] = 1.40, 95% confidence interval [CI]: 1.05-1.87 and aOR = 1.25, 95%CI: 0.83-1.90, respectively).

CONCLUSIONS

We observed an increased incidence of high-impact cLBP among Black and Hispanic patients compared to White patients. This disparity was partly explained by racial/ethnic differences in socioeconomic and back-related risk factors. Interventions that target these factors to reduce pain-related disparities should be evaluated.

CLINICALTRIALS.GOV IDENTIFIER

NCT02647658.

Nonopioid pharmacological management of acute low back pain: A level I of evidence systematic review

Acute low back pain (LBP) imposes a significant socioeconomical burden as it is the condition that, worldwide, cause the most disability. Nonetheless, the literature regarding the best pharmacological management of acute LBP is limited, and the indications available in the literature are conflicting. This work investigates whether the pharmacological management of acute LBP can effectively reduce pain and disability, and aims to identify which drugs show the highest efficacy. This systematic review was conducted according to the 2020 PRISMA statement. In September 2022, PubMed, Scopus, and Web of Science were accessed. All the randomized controlled trials investigating the efficacy of myorelaxants, nonsteroidal anti-inflammatory drugs (NSAIDs), and paracetamol for acute LPB were accessed. Only studies that investigated the lumbar spine were included. Only studies reporting on patients with acute LBP with symptom duration of less than 12 weeks were included. Only patients older than 18 years and with nonspecific low back pain were included. Studies that investigated the use of opioids in acute LBP were not considered. Data from 18 studies and 3478 patients were available. Myorelaxants and NSAIDs were effective in reducing pain and disability in acute LBP at approximately one week. The combination of NSAIDs and paracetamol was associated with a greater improvement than the use of NSAIDs alone, but paracetamol alone did not induce any significant improvement. Placebo was not effective in reducing pain. Clinical Significance: Myorelaxants, NSAIDs, and NSAIDs with paracetamol could reduce pain and disability in patients with acute LBP.

Effectiveness of Virtual Reality-Based Interventions for Managing Chronic Pain on Pain Reduction, Anxiety, Depression and Mood: A Systematic Review

(1) Background: Patients diagnosed with chronic pain suffer from long-term pain, which negatively affects their daily lives and mental health. Virtual reality (VR) technologies are considered a therapeutic tool to manage pain perception and mental health conditions. This systematic review aimed to appraise the efficacy of VR in improving pain intensity, anxiety, depression and mood among patients with chronic pain; (2) Methods: Five electronic databases were systematically searched using the terms representing VR and chronic pain. Quality assessment was conducted using Cochrane Collaboration’s tool and Newcastle-Ottawa scale; (3) Results: Seventeen peer-reviewed articles were included in this review. It was found that VR was able to reduce pain intensity in patients with phantom limb pain, chronic headache, chronic neck pain and chronic low-back pain. The effects of VR on the improvement of anxiety, depression and mood were not determined due to the inadequate amount of clinical evidence; (4) Conclusions: VR, especially immersive VR, improves pain outcomes and its effects may vary depending on the approach and study design. More research is still needed to investigate the clinical use of VR in patients with chronic pain.

Can interoceptive sensitivity provide information on the difference in the perceptual mechanisms of recurrent and chronic pain? Part I. A retrospective clinical study related to multidimensional pain assessment

OBJECTIVES

Although neurobiological research has shown that interoception plays a role in the perception of pain and its chronification, the relationship between interoceptive sensitivity and pain has not been definitively confirmed by clinical studies. The aim of this study was therefore to better understand the relationship between interoceptive sensitivity, somatization, and clinical pain, and to identify any differences in the interoceptive sensitivity of patients with recurrent vs. chronic pain.

METHODS

Scores from 43 Chronic pain subjects, assessed using ICD-11 Criteria; 42 healthy subjects (without pain or psychiatric disorders); and 38 recurrent pain subjects on the Multidimensional Assessment of Interoceptive Awareness (MAIA), Body Perception Questionnaire (BPQ-SF), Somatosensory amplification scale (SSAS), Patient Health Questionnaire (PHQ-15), Symptom Checklist-Revised (SCL-90-R), and Italian Pain Questionnaire (IPQ) were compared.

RESULTS

Negative attention to the body was indicated by higher scores of psychosomatic dimensions as SSAS, SCL90R somatization, and PHQ-15 in recurrent, but especially chronic pain (p<0.000 for all). An increase in psychosomatic dimension scores (i.e., somatization, somatosensory amplification) was associated with an increase in both autonomic nervous system reactivity (ANSR) dimension scores and the negative influence of the Not-worrying, attention regulation and trusting of the MAIA. In contrast, the presence of pain and scores for its dimensions with associated with lower supra-diaphragmatic activity as per the BPQ.

CONCLUSIONS

Pain chronification might depend on both the impairment of interoceptive sensitivity and an increase on psychosomatic dimensions via modification of ANSR hyperactivity and a reduction of the MAIA Not-worrying dimension.

Familial Episodic Pain Syndromes

Over the past decades, advances in genetic sequencing have opened a new world of discovery of causative genes associated with numerous pain-related syndromes. Familial episodic pain syndromes (FEPS) are one of the distinctive syndromes characterized by early-childhood onset of severe episodic pain mainly affecting the distal extremities and tend to attenuate or diminish with age. According to the phenotypic and genetic properties, FEPS at least includes four subtypes of FEPS1, FEPS2, FEPS3, and FEPS4, which are caused by mutations in the TRPA1, SCN10A, SCN11A, and SCN9A genes, respectively. Functional studies have revealed that all missense mutations in these genes are closely associated with the gain-of-function of cation channels. Because some FEPS patients may show a relative treatability and favorable prognosis, it is worth paying attention to the diagnosis and management of FEPS as early as possible. In this review, we state the common clinical manifestations, pathogenic mechanisms, and potential therapies of the disease, and provide preliminary opinions about future research for FEPS.

Digital Rehabilitation for Acute Low Back Pain: A Prospective Longitudinal Cohort Study

Background

Low back pain (LBP) has a lifetime prevalence of 70–80%. Access to timely and personalized, evidence-based care is key to prevent chronic progression. Digital solutions may ease accessibility to treatment while reducing healthcare-related costs.

Purpose

We aim to report the results of a fully remote digital care program (DCP) for acute LBP.

Patients and Methods

This was an interventional, single-arm, cohort study of patients with acute LBP who received a DCP. Primary outcome was the mean change in disability (Oswestry Disability Index – ODI) after 12 weeks. Secondary outcomes included change in pain (NPRS), analgesic consumption, surgery likelihood, depression (PHQ-9), anxiety (GAD-7), fear-avoidance beliefs (FABQ-PA), work productivity (WPAI) and engagement.

Results

A total of 406 patients were enrolled in the program and of those, 332 (81.8%) completed the intervention. A significant disability reduction of 55.1% (14.93, 95% CI 13.95; 15.91) was observed, corresponding to a 76.1% responder rate (30% cut-off). Disability reduction was accompanied by significant improvements in pain (61.0%), depression (55.4%), anxiety (59.5%), productivity (65.6%), fear-avoidance beliefs (46.3%), intent to pursue surgery (59.1%), and analgesic consumption (from 35.7% at baseline to 10.8% at program end). DCP-related patient satisfaction score was 8.7/10.0 (SD 1.4).

Conclusion

This study demonstrated the utility of a multimodal DCP for patients with acute LBP. Very high adherence rates and patient satisfaction were observed, alongside significant reductions in all assessed outcomes, consistent with the growing body of evidence supporting the management of acute LBP with DCPs.

Balanced Opioid Prescribing via a Clinical Trade-Off: Pain Relief vs. Adverse Effects of Discomfort, Dependence, and Tolerance/Hypersensitivity

In the backdrop of the opioid epidemic, opioid prescribing has distinct medical and social challenges. Overprescribing contributes to the ongoing opioid epidemic, whereas underprescribing yields inadequate pain relief. Moreover, opioids have serious adverse effects including tolerance and increased sensitivity to pain, paradoxically inducing more pain. Prescribing trade-offs are recognized but not modeled in the literature. We study the prescribing decisions for chronic, acute, and persistent pain types to minimize the cumulative pain that incorporates opioid adverse effects (discomfort and dependence) and the risk of tolerance or hypersensitivity (THS) developed with opioid use. After finding closed-form solutions for each pain type, we analytically investigate the sensitivity of acute pain prescriptions and examine policies on incorporation of THS, patient handover, and adaptive treatments. Our analyses show that the role of adverse effects in prescribing decisions is as critical as that of the pain level. Interestingly, we find that the optimal prescription duration is not necessarily increasing with the recovery time. We show that not incorporating THS or information curtailment at patient handovers leads to overprescribing that can be mitigated by adaptive treatments. Last, using real-life pain and opioid use data from two sources, we estimate THS parameters and discuss the proximity of our model to clinical practice. This paper has a pain management framework that leads to tractable models. These models can potentially support balanced opioid prescribing after their validation in a clinical setting. Then, they can be helpful to policy makers in assessment of prescription policies and of the controversy around over- and underprescribing.

Neurophysiological and transcriptomic predictors of chronic low back pain: Study protocol for a longitudinal inception cohort study

Chronic low back pain is one of the most common, costly, and debilitating pain conditions worldwide. Increased mechanistic understanding of the transition from acute to chronic low back and identification of predictive biomarkers could enhance the clinical assessment performed by healthcare providers and enable the development of targeted treatment to prevent and/or better manage chronic low back pain. This study protocol was designed to identify the neurological and transcriptomic biomarkers predictive of chronic low back pain at low back pain onset. This is a prospective descriptive longitudinal inception cohort study that will follow 340 individuals with acute low back pain and 40 healthy controls over 2 years. To analyze the neurophysiological and transcriptomic biomarkers of low back pain, the protocol includes psychological and pain-related survey data that will be collected beginning within 6 weeks of low back pain onset (baseline, 6, 12, 24, 52 weeks, and 2 years) and remotely at five additional time points (8, 10, 16, 20 weeks, and 18 months). Quantitative sensory testing and collection of blood samples for RNA sequencing will occur during the six in-person visits. The study results will describe variations in the neurophysiological and transcriptomic profiles of healthy pain-free controls and individuals with low back pain who either recover to pain-free status or develop chronic low back pain.

Trajectories of disability in low back pain

Four recovery trajectories from low back pain were identified: high-stable (20.9%), high-decreasing (20.7%), medium-stable (29.9%), and low-decreasing (28.5%). Pain and depression predicted the high-stable trajectory.

Introduction:

Low back pain (LBP) is the leading course of years lived with disability. Unfortunately, not much knowledge exists about distinct trajectories of recovery from disability after LBP and their potential psychological predictors.

Objectives:

Hence, the aim of the present study was to identify trajectories of functional disability in LBP and their potential baseline psychological predictors.

Methods:

A 1-year consecutive cohort (N = 1048) of patients with LBP referred to the Spine Centre if they have not improved satisfactorily from a course of treatment in primary care after 1 to 2 months were assessed by self-report questionnaires at their first visit and at 6- and 12-month follow-up. Data from patients who responded to the Roland Morris Disability Questionnaire at least twice (N = 747) were used to assess trajectories of functional disability by Latent Growth Mixture Modeling. The following measures were used as baseline predictors of the trajectories: Pain Intensity Numerical Rating Scales, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Hospital Anxiety and Depression Scale.

Results:

Four distinct trajectories were identified: high-stable (22.0%), high-decreasing (20.4%), medium-stable (29.7%), and low-decreasing (27.9%). Using the low-decreasing trajectory as reference, baseline pain intensity, depressive symptoms, and pain-catastrophizing predicted membership of all 3 symptomatic trajectories. However, using the high-decreasing trajectory as reference, age, baseline pain intensity, and depression were predictors of the high-stable trajectory.

Conclusion:

In particular, the finding of a high-stable trajectory characterized by high levels of baseline psychological distress is of potential clinical importance because psychological distress may be targeted by cognitive behavioral therapeutic approaches.

Telerehabilitation of acute musculoskeletal multi-disorders: prospective, single-arm, interventional study

Background

Acute musculoskeletal (MSK) pain is very common and associated with impaired productivity and high economic burden. Access to timely and personalized, evidence-based care is key to improve outcomes while reducing healthcare expenditure. Digital interventions can facilitate access and ensure care scalability.

Objective

Present the feasibility and results of a fully remote digital care program (DCP) for acute MSK conditions affecting several body areas.

Methods

Interventional single-arm study of individuals applying for digital care programs for acute MSK pain. Primary outcome was the mean change between baseline and end-of-program in self-reported Numerical Pain Rating Scale (NPRS) score and secondary outcomes were change in analgesic consumption, intention to undergo surgery, anxiety (GAD-7), depression (PHQ-9), fear-avoidance beliefs (FABQ-PA), work productivity (WPAI-GH) and engagement.

Results

Three hundred forty-three patients started the program, of which 300 (87.5%) completed the program. Latent growth curve analysis (LGCA) revealed that changes in NPRS between baseline and end-of-program were both statistically (p < 0.001) and clinically significant: 64.3% reduction (mean − 2.9 points). Marked improvements were also noted in all secondary outcomes: 82% reduction in medication intake, 63% reduction in surgery intent, 40% in fear-avoidance beliefs, 54% in anxiety, 58% in depression and 79% recovery in overall productivity. All outcomes had steeper improvements in the first 4 weeks, which paralleled higher engagement in this period (3.6 vs 3.2 overall weekly sessions, p < 0.001). Mean patient satisfaction score was 8.7/10 (SD 1.26).

Strengths and limitations

This is the first longitudinal study demonstrating the feasibility of a DCP for patients with acute MSK conditions involving several body areas. Major strengths of this study are the large sample size, the wide range of MSK conditions studied, the breadth of outcomes measured, and the very high retention rate and adherence level. The major limitation regards to the absence of a control group.

Conclusions

We observed very high completion and engagement rates, as well as clinically relevant changes in all health-related outcomes and productivity recovery. We believe this DCP holds great potential in the delivery of effective and scalable MSK care.

Trial registration

NCT, NCT04092946. Registered 17/09/2019;

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04891-5.

Restorative Neurostimulation for Chronic Mechanical Low Back Pain: Results from a Prospective Multi-centre Longitudinal Cohort

INTRODUCTION

Low back pain impacts most people throughout the course of their lives and contributes significantly to the global burden of disease. In some patients, symptoms resolve with little intervention, while others are amenable to surgical intervention, some cases are intractable to current care paradigms. Restorative neurostimulation is an emerging therapy for chronic mechanical low back pain.

METHODS

We conducted a prospective post-market follow-up of 42 patients treated for longstanding chronic mechanical low back pain with restorative neurostimulation. Patients were followed up at 45, 90, and 180 days and 1 and 2 years following activation of the device. Pain, disability, and health-related quality of life were recorded.

RESULTS

Among the 37 patients completing 2-year follow-up, numerical rating scale (NRS) pain scores improved from 7.0 ± 0.2 to 3.5 ± 0.3 (p < 0.001), Oswestry Disability Index (ODI) scores improved from 46.2 ± 2.2 to 29.2 ± 3.1 (p < 0.001), and health-related quality of life (measured by the EuroQol 5-Dimension 5-Level questionnaire-EQ-5D-5L) improved from 0.426 ± 0.035 to 0.675 ± 0.030 (p < 0.001). Additionally, 57% of patients experienced a greater than 50% reduction in pain, and 51% of patients benefited by a greater than 15-point reduction in ODI, both substantial improvements.

CONCLUSION

This real-world sample of patients shows that restorative neurostimulation can provide substantial and durable benefit to a cohort of patients that have traditionally had few reliable treatment options. Our findings support the continued used of this therapy in well-selected patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01985230.

Paravertebral Muscle Mechanical Properties in Patients with Axial Spondyloarthritis or Low Back Pain: A Case-Control Study

Different musculoskeletal disorders are a source of pain in the spinal region; most of them can be divided into mechanical, such as low back pain (LBP), or inflammatory origins, as is the case of axial spondyloarthritis (axSpA). Nevertheless, insufficient information is available about the muscle negative consequences of these conditions. Thus, the objective of this study was to identify whether mechanical muscle properties (MMPs) of cervical and lumbar muscles are different between patients with axSpA, subacute LBP (sLBP), and healthy controls. Furthermore, we aimed identify whether MMPs were related to sociodemographic and clinical variables in various study groups. The MMPs, sociodemographic, and clinical variables were obtained in 43 patients with axSpA, 43 subjects with sLBP, and 43 healthy controls. One-way ANOVAs and ROC curves were applied to identify whether the MMPs could differentiate between the study groups. Intra-group Pearson r coefficients to test the associations between MMPs and the rest of the variables were calculated. The results showed that axSpA subjects have a higher tone and stiffness and a lower relaxation and creep than sLBP and healthy ones (p < 0.05). All lumbar and cervical MMPs, except for decrement, could correctly classify axSpA and healthy subjects and axSpA and sLBP patients (in both cases, Area Under the Curve > 0.8). However, no MMP could differentiate between sLBP and healthy subjects. Each group had a different pattern of bivariate correlations between MMPs and sociodemographic and clinical data, with a worse state and progression of the axSpA group associated with a higher tone and stiffness in both spinal regions. This study supports that MMPs are different and show different patterns of correlations depending on the type of spinal pain.

Pain and Disability in Low Back Pain Can be Reduced Despite No Significant Improvements in Mechanistic Pain Biomarkers

OBJECTIVE

Altered balance in nociception in response to noxious stimuli is commonly reported in chronic low back pain (LBP). However, it is unclear whether an improvement in the clinical presentation is contingent on a reduction in pain sensitivity. This study investigated whether the quantitative sensory testing (QST) profile changes in people undergoing rehabilitation for LBP.

DESIGN

A prospective, observational case-control study.

METHODS

Forty males and females, 18 to 40 years' old (20 with LBP) participated in 2 sessions. QST was performed at baseline and after discharge from rehabilitation (LBP) or after 3 to 8 weeks (controls). The QST battery consisted of determining pressure-pain thresholds at the low back and shoulder, temporal summation of pain, and conditioned pain modulation. Questionnaire data was used to determine pain (Numeric Rating Scale [NRS]), disability (Roland-Morris Questionnaire [RMQ]), Fear Avoidance Beliefs (FABQ), and The Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) at baseline and discharge. The treatment effect was determined by calculating the Cohen d.

RESULTS

No significant group×time interactions or main factor effect was found for any of the QST measures. The LBP group reported a significant reduction in NRS (P<0.0002, d=1.23), RMQ (P<0.0001, d=1.58), FABQ (P<0.001, d=0.87), and in the ÖMPSQ (P<0.00001, d=1.44).

CONCLUSIONS

The results indicate that an improvement of clinical LBP is not contingent upon changes in the pain sensory profile. The value of screening pain sensitivity in LBP patients in primary care, needs to be investigated further, due to the patient population heterogeneity and the sensitivity of assessment methods.

Paravertebral Muscle Mechanical Properties and Spinal Range of Motion in Patients with Acute Neck or Low Back Pain: A Case-Control Study

Our aims were to identify potential differences in muscle mechanical properties (MMPs) of cervical and lumbar tissues and in spinal range of motion (ROM) between patients with acute low back pain (LBP) or acute neck pain (NP) and healthy controls, and to identify if ROMs and MMPs are able to identify subjects among the three groups. Clinical variables (pain, disability, fear of movement, kinesiophobia, quality of life), MMPs and ROMs were obtained in 33 subjects with acute LBP, 33 with acute NP, and 33 healthy control subjects. Between-groups differences and explanatory models to discriminate groups depending on MMPs and ROMs were calculated. The results showed that cervical tone was higher in patients with acute NP than in controls, while cervical decrement was higher in both spinal pain groups. Patients with acute NP showed reduced cervical flexion when compared to acute LBP and control groups, and also cervical rotation, but just against controls. Furthermore, lumbar flexion was reduced in patients with acute LBP when compared to those with acute NP. Cervical decrement was able to discriminate spinal pain individuals from controls in a multinominal regression (R²: Cox–Snell estimation = 0.533; Nagelkerke estimation = 0.600). Lumbar flexion differentiated patients with acute LBP and controls, whereas cervical flexion differentiated patients with acute NP and controls. This study supports a tendency of the affectation of other spinal regions when only one is affected.

Neck pain patterns and subgrouping based on weekly SMS-derived trajectories

BACKGROUND

Neck and low back pain represent dynamic conditions that change over time, often with an initial improvement after the onset of a new episode, followed by flare-ups or variations in intensity. Pain trajectories were previously defined based on longitudinal studies of temporal patterns and pain intensity of individuals with low back pain. In this study, we aimed to 1) investigate if the defined patterns and subgroups for low back pain were applicable to neck pain patients in chiropractic practice, 2) explore the robustness of the defined patterns, and 3) investigate if patients within the various patterns differ concerning characteristics and clinical findings.

METHODS

Prospective cohort study including 1208 neck pain patients from chiropractic practice. Patients responded to weekly SMS-questions about pain intensity and frequency over 43 weeks. We categorized individual responses into four main patterns based on number of days with pain and variations in pain intensity, and subdivided each into four subgroups based on pain intensity, resulting in 16 trajectory subgroups. We compared baseline characteristics and clinical findings between patterns and between Persistent fluctuating and Episodic subgroups.

RESULTS

All but two patients could be classified into one of the 16 subgroups, with 94% in the Persistent fluctuating or Episodic patterns. In the largest subgroup, "Mild Persistent fluctuating" (25%), mean (SD) pain intensity was 3.4 (0.6) and mean days with pain 130. Patients grouped as "Moderate Episodic" (24%) reported a mean pain intensity of 2.7 (0.6) and 39 days with pain. Eight of the 16 subgroups each contained less than 1% of the cohort. Patients in the Persistent fluctuating pattern scored higher than the other patterns in terms of reduced function and psychosocial factors.

CONCLUSIONS

The same subgroups seem to fit neck and low back pain patients, with pain that typically persists and varies in intensity or is episodic. Patients in a Persistent fluctuating pattern are more bothered by their pain than those in other patterns. The low back pain definitions can be used on patients with neck pain, but with the majority of patients classified into 8 subgroups, there seems to be a redundancy in the original model.

Considerations in the Assessment of Clinical Benefit with a Focus on Pain: a Regulatory Perspective

In the USA, the regulatory standard for demonstration of efficacy of a drug is evidence of clinical benefit from adequate and well-controlled clinical trials. Understanding the natural history of disease and how treatment is expected to alter its course, and gathering input from relevant stakeholders, such as patients, caregivers, and clinicians, is essential to understand the best way to measure clinical benefit in a clinical trial. Though pain intensity has been the primary outcome measure in clinical trials for pain, an array of measures assessing clinical outcomes from multiple perspectives can allow for more comprehensive interpretation of how a treatment affects patients' lives. Careful consideration should be given to how pain affects the feeling and functioning of each distinct patient population and which outcome assessment, or combination of outcome assessments, may be necessary to provide a more comprehensive view of the patient experience. The early stages of medical product development are an important opportunity to engage with regulatory agencies to discuss potential approaches to clinical trial design and outcome measurement strategies.

Pressure pain threshold and temporal summation in adults with episodic and persistent low back pain trajectories: a secondary analysis at baseline and after lumbar manipulation or sham

BACKGROUND

People with chronic low back pain (LBP) typically have increased pain sensitivity compared to healthy controls, however its unknown if pain sensitivity differs based on LBP trajectory at baseline or after manual therapy interventions. We aimed to compare baseline pressure pain threshold (PPT) and temporal summation (TS) between people without LBP, with episodic LBP, and with persistent LBP, and to compare changes over time in PPT and TS after a lumbar spinal manipulation or sham manipulation in those with LBP.

METHODS

Participants were aged 18-59, with or without LBP. Those with LBP were categorised as having either episodic or persistent LBP. PPT and TS were tested at baseline. LBP participants then received a lumbar spinal manipulation or sham, after which PPT and TS were re-tested three times over 30 min. Generalised linear mixed models were used to analyse data.

RESULTS

One hundred participants (49 female) were included and analysed. There were 20 non-LBP participants (mean age 31 yrs), 23 episodic LBP (mean age 35 yrs), and 57 persistent LBP (mean age 37 yrs). There were no significant differences in PPT or TS between groups at baseline. There was a non-significant pattern of lower PPT (higher sensitivity) from the non-LBP group to the persistent LBP group at baseline, and high variability. Changes in PPT and TS after the interventions did not differ between the two LBP groups.

DISCUSSION

We found no differences between people with no LBP, episodic LBP, or persistent LBP in baseline PPT or TS. Changes in PPT and TS following a lumbar manual therapy intervention do not appear to differ between LBP trajectories.

TRIAL REGISTRATION

The trial was prospectively registered with ANZCTR (ACTRN12617001094369).

Transitioning from acute to chronic pain: a simulation study of trajectories of low back pain

Background

Identifying how pain transitions from acute to chronic is critical in designing effective prevention and management techniques for patients’ well-being, physically, psychosocially, and financially. There is an increasingly pressing need for a quantitative and predictive method to evaluate how low back pain trajectories are classified and, subsequently, how we can more effectively intervene during these progression stages.

Methods

In order to better understand pain mechanisms, we investigated, using computational modeling, how best to describe pain trajectories by developing a platform by which we studied the transition of acute chronic pain.

Results

The present study uses a computational neuroscience-based method to conduct such trajectory research, motivated by the use of hypothalamic–pituitary–adrenal (HPA) axis activity-history over a time-period as a way to mimic pain trajectories. A numerical simulation study is presented as a “proof of concept” for this modeling approach.

Conclusions

This model and its simulation results have highlighted the feasibility and the potential of developing such a broader model for patient evaluations.

Understanding the psychosocial impact of joint hypermobility syndrome and Ehlers-Danlos syndrome hypermobility type: a qualitative interview study

PURPOSE

Little attention has been paid to psychosocial factors in Joint Hypermobility Syndrome and Ehlers-Danlos Syndrome (hypermobility type). This study sought to identify the psychosocial impact by examining participants' lived experiences; and identify characteristics of effective coping.

MATERIALS AND METHODS

Adults with Joint Hypermobility Syndrome and Ehlers-Danlos Syndrome (Hypermobility Type) were invited to discuss their own lived experiences and the impact of the condition. All met recognized criteria for clinically significant joint hypermobility, and had a self-confirmed diagnosis. The transcripts were coded and analyzed using inductive thematic analysis.

RESULTS

Seventeen participants (14 women, 3 men) purposively selected to broadly represent different genders, ages and ethnicities. Analysis identified five key themes: healthcare limitations, a lack of awareness of Joint Hypermobility, and Ehlers-Danlos Syndrome (Hypermobility Type) among healthcare professionals; a restricted life; social stigma; fear of the unknown; and ways of coping.

CONCLUSIONS

The results highlight the significant psychosocial impact on participants' lives. Coping approaches identified included acceptance, building social networks, learning about joint hypermobility, and adapting activities. Physiotherapists supported regular exercise. Further research should consider potential interventions to improve information provision, address psychological support, and increase awareness of hypermobility among healthcare professionals.Implications for rehabilitationParticipants who had help from family members to complete activities described guilt and shame, highlighting the need for a greater rehabilitation focus on maintaining independence.Difficulties with sexual relationships due to prolapse or erectile dysfunction, and associated anxieties have indicated a need for greater awareness of these issues within primary care.The provision of reliable information and materials is vital, both for healthcare professionals and patients, to reduce misinformation and fear.Physiotherapists with knowledge of Joint Hypermobility Syndrome and Ehlers-Danlos Syndrome hypermobility type were cited as sources of support and hope, which helped people to cope with and manage their condition.