The Canadian version of the National Institutes of Health minimum dataset for chronic low back pain research: reference values from the Quebec Low Back Pain Study

Trajectories of pain and depressive symptoms among people living with low back pain during the COVID-19 pandemic: a 24-month longitudinal study

Introduction: We explored trajectories of pain intensity and depressive symptoms over the first 24 months of the pandemic in people with low back pain. Methods: This longitudinal study was conducted alongside the Quebec Low Back Pain Study. Starting in April 2020 and every 3 months until July 2022, 291 participants completed an online survey. Group-based trajectory modeling was used to identify patterns of pain intensity and depressive symptoms. Onset outbreak characteristics were then put in relation with trajectory groups using multivariate logistic regression. Results: The analysis revealed 5 trajectories of pain intensity and depressive symptoms, respectively. The pain trajectories were stable mild (n = 17, 5.8%); stable moderate (n = 103, 35.4%); stable severe (n = 81, 27.8%); U-shape (n = 24, 8.3%), and inverted U-shape (n = 66, 22.7%). The trajectories of depressive symptoms were stable none (n = 58, 19.9%); stable very mild (n = 61, 21.0%); stable mild (n = 85, 29.2%); stable moderate (n = 59, 21.7%); and severe slightly improving (n = 24, 8.3%). Pre-COVID everyday/nearly everyday pain, average pain intensity, and widespread bodily pain were predictive of pain trajectory groups. Higher pre-COVID depression, acute stress disorder, and lockdown measures-related stress were associated with moderate/severe depressive trajectories. Discussion: Our findings indicated relative stability of pain and depressive symptoms among participants during the COVID-19 pandemic but also highlighted subgroups of people who experienced temporary deterioration or improvement over the first months of the pandemic that then reverted back to baseline levels. Modifiable risk factors were identified before the onset of the pandemic, which could give preventive measures in targeted populations.

A confirmatory factor analysis of an electronic format painDETECT questionnaire for patients with low back pain

BACKGROUND

The substantial burden of low back pain on patients and healthcare systems is exacerbated by unclear pathology and ineffective diagnostic methods, hindering effective management. The painDETECT questionnaire (PD-Q) has been used to facilitate the evaluation and categorization of low back pain. While preliminary validation and translations of the paper-based format of PD-Q into languages such as Spanish and Dutch have been accomplished, the underlying factor model inherent to the electronic format of the PD-Q remains to be established.

OBJECTIVE

The objective of this study was to utilise confirmatory factor analysis (CFA) to investigate the factor structure of an electronic format PD-Q among patients with neuropathic low back pain.

METHODS

This cross-sectional study was conducted at a Spinal Clinic in Sydney between November 2020 and October 2022. Eligible participants were adults over 18 with low back pain and no history of lumbar surgery or systemic co-morbidities. Participants completed the electronic format of the PD-Q, and CFA was employed to assess the validity of the suggested two-factor, nine-item structure. Recommended cut-offs for goodness-of-fit indices were used to evaluate the model fit.

RESULTS

Of the 236 patients that visited the clinic during the data collection period, 142 (71, 50% female, mean age 51.26 ± 15.28 years) participated in the study. Median pain severity was 9/10 over 4 weeks. CFA indicated strong model fit, with goodness-of-fit and comparative fit indices over 0.9, and overall internal consistency was 0.77. Construct validity analysis demonstrated the PD-Q's effectiveness in distinguishing neuropathic, mixed, and nociceptive LBP, aiding neuropathic pain evaluation in low back pain patients.

CONCLUSION

This study confirms the reliability and two-factor structure of the electronic PD-Q for neuropathic pain assessment in low back pain patients. To enhance comprehension of the clinical applicability of the electronic format PD-Q, future research should conduct clinimetric evaluations.

Risk Factors in Patients with Low Back Pain Under 40 Years Old: Quantitative Analysis Based on Computed Tomography and Magnetic Resonance Imaging mDIXON-Quant

Purpose

While low back pain (LBP) constitutes a global life disorder cause, the contribution of paraspinal muscles to its pathogenicity remains elusive. We characterized the paraspinal muscles of patients with LBP using lumbar three-dimensional computed tomography (CT) and magnetic resonance imaging (MRI) mDIXON-Quant, and evaluated the risk factors combined with clinical data.

Methods

A retrospective study involving 181 patients (10-40 years) who underwent lumbar 3D-CT and MRI mDIXON from January 1, 2021 to December 31, 2022, and divided into normal, non-chronic LBP [non-CLBP], and CLBP groups. Clinical data, paraspinal muscle cross-sectional area, Hounsfield unit for CT values, and fat fraction derived from mDIXON-Quant were compared. Three readers analyzed the images independently; intra- and interobserver agreement was measured. Spearman analysis and multiple logistic regression were used to analyze the correlation between clinical data, radiologic and paraspinal muscle parameters. A nomogram was constructed for individualized prediction.

Results

Correlation analysis revealed that body mass index, visual analog scale score, Pfirrmann grade, annulus fibrosus tear, lumbar lordosis (LL), and Modic changes correlated with LBP (all P<0.05). The Pfirrmann grade and annulus fibrosus tear showed positive correlation (r=0.673, 0.559), whereas LL was negatively correlated (r=-0.469). The multifidus CT values were negatively correlated with LBP at L4-5/L5-S1; the multifidus fat fraction was positively correlated at L4-5/L5-S1 (r=0.734, r=0.584, P<0.001). The multiple logistic regression showed that L4-5 multifidus fat fraction (P=0.046, OR=1.167), Pfirrmann grade (P=0.017, OR=0.063), LL (P=0.002, OR=0.828) and annulus fibrosus tear (P=0.005, OR=0.024) were risk factors for predicting LBP in the non-CLBP group; in the CLBP group, BMI (P=0.048 OR=1.225), L4-5 multifidus fat fraction (P=0.001 OR=1.299), LL (P=0.003, OR=0.841) and Pfirrmann classification (P=0.009, OR=0.046) were risk factors.

Conclusion

BMI, L4-5 multifidus fat fraction, LL, and Pfirrmann grade are risk factors for CLBP in patients under 40; whereas annulus fibrosus tear is an independent risk factor for non-CLBP, nomograms derived from these parameters can help predict LBP and MRI mDIXON-Quant is recommended for quantitatively analyzing paraspinal muscle fat infiltration.