Associations of socioeconomic and lifestyle characteristics, psychological symptoms, multimorbidity, and multisite pain with sciatica - a 15-year longitudinal study

BACKGROUND CONTEXT

Sciatica is defined as pain radiating from the low back to the leg, usually below the knee. It is a disabling condition that causes a major burden to health care and society. Previous evidence of the multifactorial etiology of sciatica comes mostly from cross-sectional studies. Larger, longitudinal studies with a multidimensional set of variables are needed.

PURPOSE

To examine how socioeconomic and lifestyle characteristics, psychological symptoms, multimorbidity, and multisite pain are associated with sciatica.

STUDY DESIGN

A longitudinal study of the Northern Finland Birth Cohort 1966.

PATIENT SAMPLE

In total 6,683 working-aged members of the Northern Finland Birth Cohort 1966.

OUTCOME MEASURES

Self-reported sciatic pain status over a 15-year study period.

METHODS

We conducted a 15-year longitudinal study from the age of 31 to 46. We used multivariable generalized estimation equations analysis to examine how socioeconomic characteristics (low education, unemployment, and living alone), lifestyle characteristics (overweight, obesity, current smoking, and physical inactivity), psychological symptoms (depression, anxiety), multimorbidity, and multisite pain were associated with sciatica.

RESULTS

At the age of 31, 21.1% of the study population reported sciatic pain and at the age of 46, 36.7%. Multisite pain was clearly the strongest factor associated with sciatica (odds ratio [OR] 2.61, 95% confidence interval [CI] 2.34‒2.92). In descending order of effect size, older age, low education, psychological symptoms, multimorbidity, overweight, obesity, physical inactivity and current smoking were positively associated with sciatica. Their ORs varied between 1.17 and 2.18. Living alone was negatively associated with sciatica (OR 0.81, 95% CI 0.72‒0.90).

CONCLUSIONS

Multisite pain had the strongest association with sciatica. The effect sizes of the other factors were clearly smaller. To our knowledge this is the first study to evaluate the association of multisite pain with sciatica. This finding may have considerable implications for clinical work treating patients with sciatica.

Semiautomatic Assessment of Facet Tropism From Lumbar Spine MRI Using Deep Learning: A Northern Finland Birth Cohort Study

STUDY DESIGN

This is a retrospective, cross-sectional, population-based study that automatically measured the facet joint (FJ) angles from T2-weighted axial magnetic resonance imagings (MRIs) of the lumbar spine using deep learning (DL).

OBJECTIVE

This work aimed to introduce a semiautomatic framework that measures the FJ angles using DL and study facet tropism (FT) in a large Finnish population-based cohort.

SUMMARY OF DATA

T2-weighted axial MRIs of the lumbar spine (L3/4 through L5/S1) for (n=1288) in the NFBC1966 Finnish population-based cohort were used for this study.

MATERIALS AND METHODS

A DL model was developed and trained on 430 participants' MRI images. The authors computed FJ angles from the model's prediction for each level, that is, L3/4 through L5/S1, for the male and female subgroups. Inter-rater and intrarater reliability was analyzed for 60 participants using annotations made by two radiologists and a musculoskeletal researcher. With the developed method, we examined FT in the entire NFBC1966 cohort, adopting the literature definitions of FT thresholds at 7° and 10°. The rater agreement was evaluated both for the annotations and the FJ angles computed based on the annotations. FJ asymmetry ( - was used to evaluate the agreement and correlation between the raters. Bland-Altman analysis was used to assess the agreement and systemic bias in the FJ asymmetry. The authors used the Dice score as the metric to compare the annotations between the raters. The authors evaluated the model predictions on the independent test set and compared them against the ground truth annotations.

RESULTS

This model scored Dice (92.7±0.1) and intersection over union (87.1±0.2) aggregated across all the regions of interest, that is, vertebral body (VB), FJs, and posterior arch (PA). The mean FJ angles measured for the male and female subgroups were in agreement with the literature findings. Intrarater reliability was high, with a Dice score of VB (97.3), FJ (82.5), and PA (90.3). The inter-rater reliability was better between the radiologists with a Dice score of VB (96.4), FJ (75.5), and PA (85.8) than between the radiologists and the musculoskeletal researcher. The prevalence of FT was higher in the male subgroup, with L4/5 found to be the most affected region.

CONCLUSION

The authors developed a DL-based framework that enabled us to study FT in a large cohort. Using the proposed method, the authors present the prevalence of FT in a Finnish population-based cohort.

Effectiveness of a classification-based approach to low back pain in primary care - a benchmarking controlled trial

OBJECTIVE

The aim of this study was to assess the effectiveness of classification-based approach for low back pain care in Finnish primary care.

DESIGN

A benchmarking controlled trial design was used.

SUBJECTS/PATIENTS

Three primary healthcare areas and 654 low back pain patients with or without sciatica.

METHODS

Classification-based care (using the STarT Back Tool) was implemented using organizational-, healthcare professional-, and patient-level interventions. The primary outcome was change in Patient-Reported Outcomes Measurement Information System, Physical Function (PROMIS PF-20) from baseline to 12 months.

RESULTS

No difference was found between the intervention and control in change in PROMIS PF-20 over the 12-month follow-up (mean difference 0.33 confidence interval -2.27 to 2.9, p = 0.473). Low back pain-related healthcare use, imaging, and sick leave days were significantly lower in the intervention group. Reduction in intensity of low back pain appeared to be already achieved at the 3-month follow-up (mean difference -1.3, confidence interval -2.1 to -0.5) in the intervention group, while in the control group the same level of reduction was observed at 12 months (mean difference 0.7, confidence interval -0.2 to 1.5, treatment*time p = 0.003).  Conclusion: Although classification-based care did not appear to influence physical functioning, more rapid reductions in pain intensity and reductions in healthcare use and sick leave days were observed in the intervention group.

Effects of Bariatric Surgery on Knee Articular Cartilage and Osteoarthritis Symptoms-A 12-Month Follow-Up Using T2 Relaxation Time and WOMAC Osteoarthritis Index

BACKGROUND

Obesity is a significant risk factor for osteoarthritis (OA). The most effective treatment for morbid obesity is bariatric surgery.

PURPOSE

To study the effects of potential surgically induced weight loss on knee articular cartilage and OA symptoms of obese patients over a 12-month follow-up.

STUDY TYPE

Prospective longitudinal cohort study.

SUBJECTS

45 obese patients (38 female, BMI = 42.3 ± 6.5 kg/m2) who underwent gastric bypass (intervention group), and 46 age-matched conservative-care controls (37 female, BMI = 39.8 ± 4.6 kg/m2).

FIELD STRENGTH/SEQUENCE

Multiecho spin echo sequence at 3 T.

ASSESSMENT

Knee cartilage T2 measurements and WOMAC Indices were measured presurgery and after 12 months. The intervention group was split into successful (≥20% total weight loss (TWL)) and unsuccessful (<20% TWL) weight loss groups. T2 and WOMAC indices were also measured in controls at baseline and after 12 months. Changes among the three groups were analyzed.

STATISTICAL TESTS

Analysis of variance (significance level 0.05).

RESULTS

Twenty-six (58%) intervention patients achieved ≥20% TWL. The <20% TWL group demonstrated significantly more T2 reduction in the deep lateral femur over 12 months compared with the ≥20% TWL group (-3.83 ± 8.18 msec vs. 2.47 ± 6.54 msec, respectively), whereas no significant differences were observed on the medial femoral compartment (P = 0.385, P = 0.551, and P = 0.511 for bulk, superficial and deep regions, respectively). Changes in WOMAC indices over 12 months were significantly greater in the ≥20% TWL group compared with controls. In the <20% TWL group, pain significantly improved over 12 months compared with controls, while stiffness and function changes were not statistically significant (P = 0.063 and P = 0.051, respectively).

DATA CONCLUSION

Cartilage matrix, measured by T2, showed improvement on lateral femoral cartilage with <20% TWL compared with ≥20% TWL. Bariatric surgery provided significant improvements in knee symptoms with ≥20% TWL compared with conservative WL. This effect is also seen to some extent with <20% TWL compared with conservative WL.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 4.

The Clinical Significance of the Modic Changes Grading Score

STUDY DESIGN

Cross-sectional retrospective observational study.

OBJECTIVE

To evaluate the reliability and clinical utility of the Modic changes (MC) grading score.

METHOD

Patients from the Danish national spine registry, DaneSpine, scheduled for lumbar discectomy were identified. MRI of patients with MC were graded based on vertical height involvement: Grade A (<25%), Grade B (25%-50%), and Grade C (>50%). All MRIs were reviewed by 2 physicians to evaluate the reliability of the MC grade.

RESULTS

Of 213 patients included, 142 patients had MC, 71 with MC-1 and 71 with MC-2; 34% were Grade A, 45% were Grade B, and 21% were Grade C. MC grade demonstrated substantial intra-rater (κ = .68) and inter-rater (κ = .61) reliability. A significantly higher proportion (n = 40, 57%) of patients with MC-1 had a severe MC grade compared to patients with MC-2 (n = 30, 43%, P < .001). Severe MC grade was associated with the presence of severe lumbar disc degeneration (DD) (Pfirrmann grade = V, P = .024), worse preoperative ODI (52.49 vs 44.17, P = .021) and EQ-5D scores (.26 vs .46, P = .053). MC alone including type was not associated with a significant difference in patient-reported outcomes (P > .05).

CONCLUSION

The MC grade score was demonstrated to have substantial intra- and inter-observer reliability. Severe MC grade was associated with both severe DD and MC type, being more prevalent in patients with MC-1. The MC grade was also significantly associated with worse disability and reduced health-related quality of life. Results from the study suggest that MC grade is more clinically important than MC type.

Discovery of circulating blood biomarkers in patients with and without Modic changes of the lumbar spine: a preliminary analysis

PURPOSE

The following study aimed to determine the existence of blood biomarkers in symptomatic patients with or without lumbar Modic changes (MC).

METHODS

A cross-sectional sub-analyses of a prospective cohort was performed. Fasting blood samples were collected from patients with and without lumbar MC who had undergone spinal fusion or microdiscectomy. An 80-plex panel and CCL5/RANTES were used to assess preoperative plasma cytokine concentrations. Patient demographics and imaging phenotypes were also assessed.

RESULTS

Thirty-one subjects were analysed (n = 18 no MC; n = 13 MC). No significant differences were found in age, sex, body mass index, smoking and alcohol history, and surgical procedure (i.e. fusion, decompression) between the two groups (p > 0.05). Several statistically significant blood biomarkers in MC patients were identified, including elevated levels of C-C Motif Chemokine Ligand 5 (CCL5, p = 0.0006), while Macrophage Migration Inhibitory Factor (MIF) was significantly lower (p = 0.009). Additionally, C-X-C Motif Chemokine Ligand 5 (CXCL5, p = 0.052), Pentraxin 3 (PTX3, p = 0.06) and Galectin-3 (Gal-3, p = 0.07) showed potential relevance. Moreover, MC patients exhibited significantly higher levels of disc degeneration (p = 0.0001) and displacement severity (p = 0.020). Based on multivariate analyses and controlling for disc degeneration/displacement, CCL5 (OR 1.02; 95% CI 1.002-1.033; p = 0.028) and MIF (OR 0.60; 95% CI 0.382-0.951; p = 0.030) were independently associated with MC patients.

CONCLUSION

This "proof-of-concept" study is the first to identify specific and significantly circulating blood biomarkers associated with symptomatic patients with lumbar MC, independent of disc alterations of degeneration and/or bulges/herniations. Specifically, differences in CCL5 and MIF protein levels were significantly noted in MC patients compared to those without MC.

Association between vertebral cross-sectional area and lumbar disc displacement - a population-based study

PURPOSE

Vertebral dimensions may constitute a potential risk factor for degenerative changes in the spine. Previous studies have found a positive association between vertebral height and both type 2 Modic changes and intervertebral disc height loss. Also, vertebral endplate size has been associated with disc degeneration. However, only a few studies have investigated the association between vertebral dimensions and lumbar disc displacement (LDD). This study aimed to investigate the association between vertebral cross-sectional area (CSA) and LDD among the general middle-aged Finnish population. We hypothesized that larger vertebral CSA is associated with LDD.

MATERIALS AND METHODS

The study was conducted by using data from the Northern Finland Birth Cohort 1966 (NFBC1966). At the age of 46, a subpopulation of NFBC1966 underwent clinical examinations including magnetic resonance imaging (MRI) (n = 1249). MRI scans were used to measure L4 CSA and evaluate the presence of LDD (bulge, protrusion, and extrusion/sequestration) in the adjacent discs. The association between L4 CSA and LDD was analysed using logistic regression, with adjustment for sex, education, body mass index, leisure-time physical activity, smoking, diet, and L4 height.

RESULTS

Larger L4 CSA was associated with LDD; an increase of 1 cm2 in vertebral CSA elevated the odds of LDD relative to no LDD by 10% (adjusted odds ratio 1.10, 95% CI 1.01-1.19). The association was similar among either sex.

CONCLUSIONS

Larger L4 vertebral CSA was associated with LDD in our study sample. Even though smaller vertebral size exposes our vertebrae to osteoporotic fractures, it simultaneously seems to protect us from LDD.

Pressure Pain Sensitivity and Chronotype: A Population-based Study of Middle-aged Finns

Evening chronotype individuals experience pain more often than morning chronotypes, but relationships with pain sensitivity have rarely been studied. We examined whether chronotype is associated with pressure pain sensitivity, with special reference to mental health disorders, insomnia, and chronic musculoskeletal (MSK) pain as potential moderating factors. The study sample consisted of members of the Northern Finland Birth Cohort 1966 aged 46. Pressure pain threshold and tolerance were measured via the standardized protocol, categorized as lowest quartile versus others. Chronotype (morning [M; the reference], intermediate [I], and evening [E]) was defined using the Short Morningness-Eveningness questionnaire. Sex-stratified binary logistic regression models were separately adjusted for education, body mass index, long-term diseases (fully adjusted model), and for mental health disorders, insomnia, and chronic MSK pain (a residual confounding analysis). Interaction terms (Chronotype × Mental health/insomnia/chronic MSK pain) were tested. The study had 2,132 males and 2,830 females. The E-type males had 1.5-fold odds of having a low pain threshold (fully adjusted odds ratio [OR] 1.45, 95% confidence interval 1.05-2.00) and pressure pain tolerance (fully adjusted OR 1.47, 1.07-2.02), in comparison to M-types. Having a mental health disorder intensified the association with low pain threshold fourfold (4.06, 1.56-10.6). Being an E-type female was also associated with a low pain threshold, but the association was statistically nonsignificant (fully adjusted OR 1.18, .90-1.53). No statistically significant interactions were found among females. These results emphasize the role of chronotype in pain sensitivity and add an understanding of pain experience in light of innate circadian types. PERSPECTIVE: Male evening chronotypes are more sensitive to pain than morning chronotypes. Diagnosed mental health disorders in particular indicate a low pain threshold for evening chronotype males.

Cartilaginous endplates: A comprehensive review on a neglected structure in intervertebral disc research

The cartilaginous endplates (CEP) are key components of the intervertebral disc (IVD) necessary for sustaining the nutrition of the disc while distributing mechanical loads and preventing the disc from bulging into the adjacent vertebral body. The size, shape, and composition of the CEP are essential in maintaining its function, and degeneration of the CEP is considered a contributor to early IVD degeneration. In addition, the CEP is implicated in Modic changes, which are often associated with low back pain. This review aims to tackle the current knowledge of the CEP regarding its structure, composition, permeability, and mechanical role in a healthy disc, how they change with degeneration, and how they connect to IVD degeneration and low back pain. Additionally, the authors suggest a standardized naming convention regarding the CEP and bony endplate and suggest avoiding the term vertebral endplate. Currently, there is limited data on the CEP itself as reported data is often a combination of CEP and bony endplate, or the CEP is considered as articular cartilage. However, it is clear the CEP is a unique tissue type that differs from articular cartilage, bony endplate, and other IVD tissues. Thus, future research should investigate the CEP separately to fully understand its role in healthy and degenerated IVDs. Further, most IVD regeneration therapies in development failed to address, or even considered the CEP, despite its key role in nutrition and mechanical stability within the IVD. Thus, the CEP should be considered and potentially targeted for future sustainable treatments.

Chronic disease clusters are associated with prolonged, bothersome, and multisite musculoskeletal pain: a population-based study on Northern Finns

BACKGROUND

Chronic diseases often accumulate with musculoskeletal (MSK) pain. However, less evidence is available on idiosyncratic patterns of chronic diseases and their relationships with the severity of MSK pain in general MSK pain populations.

MATERIAL AND METHODS

Questionnaire-based data on physician-diagnosed chronic diseases, MSK pain and its dimensions (frequency, intensity, bothersomeness, and the number of pain sites), and confounders were collected from the Northern Finland Birth Cohort 1966 at the age of 46. Latent Class Analysis (LCA) was used to identify chronic disease clusters among individuals who reported any MSK pain within the previous year (n = 6105). The associations between chronic disease clusters, pain dimensions, and severe MSK pain, which was defined as prolonged (over 30 d within the preceding year), bothersome (Numerical Rating Scale >5), and multisite (two or more pain sites) pain, were analyzed using logistic regression and general linear regression models, adjusted for sex and educational level (n for the full sample = 4768).

RESULTS

LCA resulted in three clusters: Metabolic (10.8% of the full sample), Psychiatric (2.9%), and Relatively Healthy (86.3%). Compared to the Relatively Healthy cluster, the Metabolic and Psychiatric clusters had higher odds for daily pain and higher mean pain intensity, bothersomeness, and the number of pain sites. Similarly, the odds for severe MSK pain were up to 75% (95% confidence interval: 44%-113%) and 155% (81%-259%) higher in the Metabolic and Psychiatric clusters, respectively, after adjustments for sex and educational level.

CONCLUSIONS

Distinct patterns of chronic disease accumulation can be identified in the general MSK pain population. It seems that mental and metabolic health are at interplay with severe MSK pain. These findings suggest a potential need to screen for psychiatric and metabolic entities of health when treating working-aged people with MSK pain.Key messagesThis large study on middle-aged people with musculoskeletal pain aimed to examine the idiosyncratic patterns of chronic diseases and their relationships with the severity of musculoskeletal pain. Latent class cluster analysis identified three chronic disease clusters: Psychiatric, Metabolic, and Relatively Healthy. People with accumulated mental (Psychiatric cluster) or metabolic diseases (Metabolic cluster) experienced more severe pain than people who were relatively healthy (Relatively Healthy cluster). These findings suggest a potential need to screen for psychiatric and metabolic entities of health when treating working-aged people with MSK pain.

Roux-en-Y versus one-anastomosis gastric bypass (RYSA study): weight loss, metabolic improvements, and nutrition at 1 year after surgery, a multicenter randomized controlled trial

OBJECTIVE

Although it has been suggested that one-anastomosis gastric bypass (OAGB) is metabolically superior to the "gold standard," i.e., Roux-en-Y gastric bypass (RYGB), there is little robust evidence to prove it. Because this result may arise from the typically longer length of bypassed intestine in OAGB, here, the authors standardized the bypass length in RYGB and OAGB and compared weight loss and metabolic outcomes in a randomized controlled trial.

METHODS

The authors randomized 121 bariatric patients to RYGB (n = 61) or OAGB (n = 60) in two Finnish University Hospitals and measured weight; body composition; metabolic features (insulin sensitivity, lipids, inflammation, nutrition); and comorbidities before and 6 and 12 months after the operation.

RESULTS

Total weight loss was similar in RYGB and OAGB at 6 months (mean: 21.2% [95% CI: 19.4-23.0] vs. 22.8% [95% CI: 21.5-24.1], p = 0.136) and 12 months (25.4% [95% CI: 23.4-27.5] vs. 26.1% [95% CI: 24.2-28.9], p = 0.635). Insulin sensitivity, lipids, and inflammation improved similarly between the groups (p > 0.05). Remission of type 2 diabetes and hypercholesterolemia was marked and similar (p > 0.05) but the use of antihypertensive medications was lower (p = 0.037) and hypertension tended to improve more (p = 0.053) with RYGB versus OAGB at 12 months. Higher rates of vitamin D-25 deficiency (p < 0.05) and lower D-25 levels were observed with OAGB versus RYGB throughout the follow-up (p < 0.001). No differences in adverse effects were observed.

CONCLUSIONS

RYGB and OAGB were comparable in weight loss, metabolic improvement, remission of diabetes and hypercholesterolemia, and nutrition at 1-year follow-up. Vitamin D-25 deficiency was more prevalent with OAGB, whereas reduction in antihypertensive medications and hypertension was greater with RYGB. There is no need to change the current practices of RYGB in favor of OAGB.

Economic burden of osteoarthritis - multi-country estimates of direct and indirect costs from the BISCUITS study

Data from 'BISCUITS', a large Nordic cohort study linking several registries, were used to estimate differences in average direct and indirect costs between patients with osteoarthritis and controls (matched 1:1 based on birth year and sex) from the general population in Sweden, Norway, Finland and Denmark for 2017. Patients ≥18 years with ≥1 diagnosis of osteoarthritis (ICD-10: M15-M19) recorded in specialty or primary care (the latter available for a subset of patients in Sweden and for all patients in Finland) during 2011-2017 were included. Patients with a cancer diagnosis (ICD-10: C00-C43/C45-C97) were excluded. Productivity loss (sick leave and disability pension) and associated indirect costs were estimated among working-age adults (18-66 years). In 2017, average annual incremental direct costs among adults with osteoarthritis (n=1,157,236) in specialty care relative to controls ranged between €1,259 and €1,693 (p<0.001) per patient across all countries. Total average annual incremental costs were €3,224-€4,969 (p<0.001) per patient. Healthcare cost differences were mainly explained by osteoarthritis patients having more surgeries. However, among patients with both primary and secondary care data, primary care costs exceeded the costs of surgery. Primary care constituted 41 and 29 % of the difference in direct costs in Sweden and Finland, respectively. From a societal perspective, the total economic burden of osteoarthritis is substantial, and the incremental cost was estimated to €1.1-€1.3 billion yearly for patients in specialty care across the Nordic countries. When including patients in primary care, incremental costs rose to €3 billion in Sweden and €1.8 billion in Finland. Given the large economic impact, finding cost-effective and safe therapeutic strategies for these patients will be important.

Trends of Low Back Pain Research in Older and Working-Age Adults from 1993 to 2023: A Bibliometric Analysis

Although the number of publications focusing on low back pain in older adults (LBP-O) and working-age adults (LBP-W) has been growing for decades, comparative research trends in these two populations, which may help to guide future investigation, have not been rigorously explored. This analysis aimed to describe publication patterns and trends of research targeting LBP-O and LBP-W over the last three decades. Peer-reviewed LBP-O and LBP-W articles published between 1993 and 2023 were retrieved from the Web of Science, which provided the details of annual publication volume, and prominent journals/countries/institutions. The relationship between the annual publication volumes and years was analyzed by Spearman correlation analysis. The hot topics and emerging trends were analyzed by VOSviewer and CiteSpace, respectively. A total of 4217 LBP-O-related and 50,559 LBP-W-related documents were included. The annual publication volumes of LBP-O and LBP-W articles increased over the years (r=0.995 to 0.998, p<0.001). The United States had the highest number of prominent institutions publishing relevant articles. The most prolific journal for LBP-O (5.4%) and LBP-W-related (6.1%) papers is the journal "Spine". Cognitive behavioral therapy, intervertebral disc (IVD) degeneration, physiotherapy, physical activity, and walking were the recent hot topics and physical activity was an emerging trend in LBP-O, while surgery and IVD degeneration (also a hot topic) were emerging trends in LBP-W. This study highlights the paucity of LBP-O-related research in the past. The United States and the journal Spine stand out in LBP research. The research trend of physical activity in LBP-O is consistent with the recognized importance of physical activity for older adults in general, and for managing LBP-O in particular. Conversely, the emerging trends of surgery and intervertebral disc degeneration in LBP-W research highlight a focus on the biomedical model of LBP despite LBP being a biopsychosocial condition.

Measuring the determinants of implementation behavior in multiprofessional rehabilitation

BACKGROUND

The Determinants of Implementation Behavior Questionnaire (DIBQ) measures facilitators or barriers of healthcare professionals' implementation behaviors based on the current implementation research on practice and policy. The DIBQ covers 18 domains of the Theoretical Domains Framework and consists of 93 items. A previously tailored version (DIBQ-t) covering 10 domains and 28 items focuses on implementing best-practice low back pain care.

AIM

To tailor a shortened version of DIBQ to multiprofessional rehabilitation context with cross-cultural adaptation to Finnish language.

DESIGN

A two-round Delphi study.

SETTING

National-level online survey.

POPULATION

Purposively recruited experts in multiprofessional rehabilitation (N.=25).

METHODS

Cross-cultural translation of DIBQ to Finnish was followed by a two-round Delphi survey involving diverse experts in rehabilitation (physicians, physiotherapists, occupational therapists, psychologists, nursing scientists, social scientists). In total, 25 experts in Round 1, and 21 in Round 2 evaluated the importance of DIBQ items in changing professionals' implementation behavior by rating on a 5-point Likert Scale (1 = Strongly Disagree, 5 = Strongly Agree) of including each item in the final scale. Consensus to include an item was defined as a mean score of ≥4 by ≥75% of Delphi participants. Open comments were analyzed using inductive content analysis. Items with agreement of ≤74% were either directly excluded or reconsidered and modified depending on qualitative judgements, amended with experts' suggestions. After completing an analogous second-round, a comparison with DIBQ-t was performed. Lastly, the relevance of each item was indexed using content validity index on item-level (I-CVI) and scale-level (S-CVI/Ave).

RESULTS

After Round 1, 17 items were included and 48 excluded by consensus whereas 28 items were reconsidered, and 20 items added for Round 2. The open comments were categorized as: 1) "modifying"; 2) "supportive"; and 3) "critical". After Round 2, consensus was reached regarding all items, to include 21 items. After comparison with DIBQ-t, the final multiprofessional DIBQ (DIBQ-mp) covers 11 TDF domains and 21 items with I-CVIs of ≥0.78 and S-CVI/Ave of 0.93.

CONCLUSIONS

A Delphi study condensed a DIBQ-mp with excellent content validity for multiprofessional rehabilitation context.

CLINICAL REHABILITATION IMPACT

A potential tool for evaluating determinants in implementing evidence-based multiprofessional rehabilitation interventions.

Degenerative cervical spine changes among early career fighter pilots: a 5-year follow-up

INTRODUCTION

Degenerative changes of the cervical spine often cause disability and flight duty limitations among Finnish Air Force (FINAF) fighter pilots. We aimed to study the effect of +Gz exposure on degenerative changes in the cervical spine by comparing cervical MRIs of FINAF fighter pilots and controls.

METHODS

At baseline, the volunteer study population consisted of 56 20-year-old FINAF male fighter pilots (exposure group) and 56 21-year-old Army and Navy cadets (control group). Both groups underwent MRI of the cervical spine at the baseline and after 5 years. Degenerative changes evaluated using MRI included intervertebral disc (IVD) degeneration (Pfirrmann classification), disc herniations, uncovertebral arthrosis, Schmorl's nodes, Modic changes, spinal canal stenosis, kyphosis and scoliosis.

RESULTS

The degree of IVD degeneration in the whole cervical spine increased significantly in both populations with no between-group differences. The prevalence of disc herniations also tended to increase in both populations with no difference in the incidence over the follow-up. However, pilots proved to have more disc herniations at the baseline and at the follow-up. There were virtually no between-group differences in other assessed degenerative changes.

DISCUSSION

We found that IVD degeneration and the prevalence of disc herniations increased at a similar rate for fighter pilots and non-flying military students when all cervical levels were summed up. The lack of difference may be explained by the relatively low cumulative +Gz exposure during the first 5 years of a pilots' career.

A prognostic risk score for development and spread of chronic pain

Chronic pain is a complex condition influenced by a combination of biological, psychological and social factors. Using data from the UK Biobank (n = 493,211), we showed that pain spreads from proximal to distal sites and developed a biopsychosocial model that predicted the number of coexisting pain sites. This data-driven model was used to identify a risk score that classified various chronic pain conditions (area under the curve (AUC) 0.70-0.88) and pain-related medical conditions (AUC 0.67-0.86). In longitudinal analyses, the risk score predicted the development of widespread chronic pain, the spreading of chronic pain across body sites and high-impact pain about 9 years later (AUC 0.68-0.78). Key risk factors included sleeplessness, feeling 'fed-up', tiredness, stressful life events and a body mass index >30. A simplified version of this score, named the risk of pain spreading, obtained similar predictive performance based on six simple questions with binarized answers. The risk of pain spreading was then validated in the Northern Finland Birth Cohort (n = 5,525) and the PREVENT-AD cohort (n = 178), obtaining comparable predictive performance. Our findings show that chronic pain conditions can be predicted from a common set of biopsychosocial factors, which can aid in tailoring research protocols, optimizing patient randomization in clinical trials and improving pain management.

Early disc degeneration in radiotherapy-treated childhood brain tumor survivors

BACKGROUND

Childhood brain tumor (BT) survivors have an increased risk of treatment-related late effects, which can reduce health-related quality of life and increase morbidity. This study aimed to investigate lumbar disc degeneration in magnetic resonance imaging (MRI) in adult survivors of radiotherapy-treated childhood BT compared to age and sex-matched population controls.

METHODS

In this cross-sectional comparative study, 127 survivors were identified from hospital registries. After a mean follow-up of 20.7 years (range 5-33.1), 67 survivors (mean age 28.4, range 16.2-43.5) were investigated with MRI and compared to 75 sex-matched population-based controls. Evaluated MRI phenotypes included Pfirrmann grading, , intervertebral disc protrusions, extrusions, and high-intensity-zone-lesions (HIZ). Groups were also compared for known risk factors of lumbar intervertebral disc (IVD) degeneration.

RESULTS

Childhood BT survivors had higher Pfirrmann grades than controls at all lumbar levels (all p < 0.001). Lumbar disc protrusions at L4-5 (p = 0.02) and extrusions at L3-4 (p = 0.04), L4-5 (p = 0.004), and L5-S1 (p = 0.01) were significantly more common in the BT group compared to the control. The survivor cohort also had significantly more HIZ-lesons than the controls (n=13 and n=1, p=0.003). Age at diagnosis was associated with lower degree of IVD degeneration (p < 0.01). Blood pressure correlated with IVD degeneration (P < 0.05).

CONCLUSIONS

Signs of early disc degeneration related to tumor treatment can be seen in the IVDs of survivors. Disc degeneration was more severe in children treated in adolescence.

The Örebro Musculoskeletal Pain Screening Questionnaire-Short Form and 2-year follow-up of registered work disability

BACKGROUND

The Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) was developed to identify psychological and functioning-related risk factors among individuals with musculoskeletal pain at risk of work disability. This study aimed to examine whether the short version of the ÖMPSQ (ÖMPSQ-SF) can be used for this purpose, using registry-based outcomes.

METHODS

The ÖMPSQ-SF was completed by the members of the Northern Finland Birth Cohort 1966 at the age of 46 years (baseline). These data were enriched with national registers, including information on sick leaves and disability pensions (indicators of work disability). The associations between the ÖMPSQ-SF categories (low-, medium- and high risk) and work disability over a 2-year follow-up were analysed using negative binomial regression and binary logistic regression models. We made adjustments for sex, baseline education level, weight status and smoking.

RESULTS

Overall, 4063 participants provided full data. Of these, 90% belonged to the low-risk, 7% to the medium-risk and 3% to the high-risk group. Compared to the low-risk group, the high-risk group had a 7.5 [Wald 95% confidence interval (CI) 6.2-9.0] times higher number of sick leave days and 16.1 (95% CI 7.1-36.8) times higher odds of disability pension after adjustments in the 2-year follow-up.

CONCLUSIONS

: Our study suggests that the ÖMPSQ-SF could be used for predicting registry-based work disability at midlife. Those allocated to the high-risk group seemed to have a particularly great need of early interventions to support their work ability.

Association of accelerometer-measured physical activity, back static muscular endurance and abdominal obesity with radicular pain and non-specific low back pain

Low back pain (LBP) is the leading cause of disability worldwide and often associated with lifestyle factors. However, studies further examining the role of these lifestyle factors in non-specific low back pain in comparison with radicular pain are sparse. The aim of this cross sectional study was to investigate how diverse lifestyle factors are associated with LBP. The study population of 3385 middle aged adults with and without low back pain was drawn from a large Birth 1966 Cohort. Outcome measures were steps per day, abdominal obesity, physical activity and endurance of the back muscles. Back static muscular endurance, abdominal obesity and physical activity were measured by means of the Biering-Sørensen test, waist circumference and a wrist worn accelerometer, respectively. Logistic regression analysis was applied to estimate associations of back static muscular endurance, abdominal obesity and accelerometer-measured physical activity with non-specific low back pain and radicular pain. An additional 1000 steps per day were associated with 4% lower odds of having non-specific low back pain. Participants with abdominal obesity had 46% higher odds of having radicular pain, whereas increases of 10 s in back static muscular endurance and 10 min in daily vigorous physical activity were associated with 5% and 7% lower odds of having radicular pain, respectively. In this population-based study, non-specific low back pain and radicular pain were associated with different lifestyle and physical factors at midlife. Non-specific low back pain was associated only with the average daily number of steps, whereas abdominal obesity was the strongest determinant of radicular pain, followed by vigorous physical activity and back static muscular endurance. The findings of this study contribute to better understand the role of lifestyle factors in both non-specific low back pain and radicular pain. Future longitudinal studies are required to explore causality.

The role of co-occurring insomnia and mental distress in the association between lumbar disc degeneration and low back pain related disability

BACKGROUND

Lumbar disc degeneration (LDD) is associated with low back pain (LBP). Although both insomnia and mental distress appear to influence the pain experience, their role in the association between LDD and LBP is uncertain. Our objective was to investigate the role of co-occurring insomnia and mental distress in the association between LDD and LBP-related disability.

METHODS

A total of 1080 individuals who had experienced LBP during the previous year underwent 1.5-T lumbar magnetic resonance imaging, responded to questionnaires, and participated in a clinical examination at the age of 47. Full data was available for 843 individuals. The presence of LBP and LBP-related disability (numerical rating scale, range 0-10) were assessed using a questionnaire. LDD was assessed by a Pfirrmann-based sum score (range 0-15, higher values indicating higher LDD). The role of insomnia (according to the five-item Athens Insomnia Scale) and mental distress (according to the Hopkins Symptom Check List-25) in the association between the LDD sum score and LBP-related disability was analyzed using linear regression with adjustments for sex, smoking, body mass index, education, leisure-time physical activity, occupational physical exposure, Modic changes, and disc herniations.

RESULTS

A positive association between LDD and LBP-related disability was observed among those with absence of both mental distress and insomnia (adjusted B = 0.132, 95% CI = 0.028-0.236, p = 0.013), and among those with either isolated mental distress (B = 0.345 CI = 0.039-0.650, p = 0.028) or isolated insomnia (B = 0.207, CI = 0.040-0.373, p = 0.015). However, among individuals with co-occurring insomnia and mental distress, the association was not significant (B = -0.093, CI = -0.346-0.161, p = 0.470).

CONCLUSIONS

LDD does not associate with LBP-related disability when insomnia and mental distress co-occur. This finding may be useful when planning treatment and rehabilitation that aim to reduce disability among individuals with LDD and LBP. Future prospective research is warranted.

External Validation of SpineNet, an Open-Source Deep Learning Model for Grading Lumbar Disk Degeneration MRI Features, Using the Northern Finland Birth Cohort 1966

STUDY DESIGN

This is a retrospective observational study to externally validate a deep learning image classification model.

OBJECTIVE

Deep learning models such as SpineNet offer the possibility of automating the process of disk degeneration (DD) classification from magnetic resonance imaging (MRI). External validation is an essential step to their development. The aim of this study was to externally validate SpineNet predictions for DD using Pfirrmann classification and Modic changes (MCs) on data from the Northern Finland Birth Cohort 1966 (NFBC1966).

SUMMARY OF DATA

We validated SpineNet using data from 1331 NFBC1966 participants for whom both lumbar spine MRI data and consensus DD gradings were available.

MATERIALS AND METHODS

SpineNet returned Pfirrmann grade and MC presence from T2-weighted sagittal lumbar MRI sequences from NFBC1966, a data set geographically and temporally separated from its training data set. A range of agreement and reliability metrics were used to compare predictions with expert radiologists. Subsets of data that match SpineNet training data more closely were also tested.

RESULTS

Balanced accuracy for DD was 78% (77%-79%) and for MC 86% (85%-86%). Interrater reliability for Pfirrmann grading was Lin concordance correlation coefficient=0.86 (0.85-0.87) and Cohen κ=0.68 (0.67-0.69). In a low back pain subset, these reliability metrics remained largely unchanged. In total, 20.83% of disks were rated differently by SpineNet compared with the human raters, but only 0.85% of disks had a grade difference >1. Interrater reliability for MC detection was κ=0.74 (0.72-0.75). In the low back pain subset, this metric was almost unchanged at κ=0.76 (0.73-0.79).

CONCLUSIONS

In this study, SpineNet has been benchmarked against expert human raters in the research setting. It has matched human reliability and demonstrates robust performance despite the multiple challenges facing model generalizability.

Family structure and multisite musculoskeletal pain in adolescence: a Northern Finland Birth Cohort 1986 study

BACKGROUND

Family structure is suggested to be associated with adolescent pain, but evidence on its association with multisite MS pain is sparse. The purpose of this cross-sectional study was to investigate the potential associations between family structure ('single-parent family', 'reconstructed family', and 'two-parent family') and multisite musculoskeletal (MS) pain in adolescence.

METHODS

The dataset was based on the 16-year-old Northern Finland Birth Cohort 1986 adolescents with available data on family structure, multisite MS pain, and a potential confounder (n = 5,878). The associations between family structure and multisite MS pain were analyzed with binomial logistic regression and modelled as unadjusted, as the evaluated potential confounder, mother's educational level, did not meet the criteria for a confounder.

RESULTS

Overall, 13% of the adolescents had a 'single-parent family' and 8% a 'reconstructed family'. Adolescents living in a single-parent family had 36% higher odds of multisite MS pain compared to adolescents from two-parent families (the reference) (Odds Ratio [OR]: 1.36, 95% Confidence Interval [CI]: 1.17 to 1.59). Belonging to a 'reconstructed family' was associated with 39% higher odds of multisite MS pain (OR 1.39, 1.14 to 1.69).

CONCLUSION

Family structure may have a role in adolescent multisite MS pain. Future research is needed on causality between family structure and multisite MS pain, to establish if there is a need for targeted support.

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.

Burden of disease and management of osteoarthritis and chronic low back pain: healthcare utilization and sick leave in Sweden, Norway, Finland and Denmark (BISCUITS): study design and patient characteristics of a real world data study

OBJECTIVES

Osteoarthritis (OA) and chronic low back pain (CLBP) are common musculoskeletal disorders with substantial patient and societal burden. Nordic administrative registers offer a unique opportunity to study the impact of these conditions in the real-world setting. The Burden of Disease and Management of Osteoarthritis and Chronic Low Back Pain: Health Care Utilization and Sick Leave in Sweden, Norway, Finland and Denmark (BISCUITS) study was designed to study disease prevalence and the societal and economic burden in broad OA and CLBP populations.

METHODS

Patients in Sweden, Norway, Finland and Denmark with diagnoses of OA or CLBP (low back pain record plus ≥2 pain relief prescriptions to indicate chronicity) were identified in specialty care, in primary care (Sweden and Finland) and in a quality-of-care register (Sweden). Matched controls were identified for the specialty care cohort. Longitudinal data were extracted on prevalence, treatment patterns, patient-reported outcomes, social and economic burden.

RESULTS

Almost 1.4 million patients with OA and 0.4 million with CLBP were identified in specialty care, corresponding to a prevalence in the Nordic countries of 6.3 and 1.9%, respectively. The prevalence increased to 11-14% for OA and almost 6% for CLBP when adding patients identified in primary care. OA patients had a higher Elixhauser comorbidity index (0.66 vs. 0.46) and were using opioids (44.7 vs. 10.2%) or long-term nonsteroidal anti-inflammatory drug (NSAIDs) (20.9 vs. 4.5%) more than four times as often as compared to controls. The differences were even larger for CLBP patients compared to their controls (comorbidity index 0.89 vs. 0.39, opioid use 77.7 vs. 9.4%, and long-term NSAID use 37.2 vs. 4.8%).

CONCLUSIONS

The BISCUITS study offers an unprecedented, longitudinal healthcare data source to quantify the real-world burden of more than 1.8 million patients with OA or CLBP across four countries. In subsequent papers we aim to explore among others additional outcomes and subgroups of patients, primarily those patients who may benefit most from better healthcare management.

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.

Oral Zoledronic acid bisphosphonate for the treatment of chronic low back pain with associated Modic changes: A pilot randomized controlled trial

To assess the safety and efficacy of oral 50 mg Zoledronic acid (ZA) bisphosphate once-a-week for 6-weeks to placebo among patients with chronic low back pain (cLBP) and Modic changes (MC) on MRI. A parallel, double-blinded randomized controlled study was performed at a single center, consisted of 25 subjects with cLBP and MC that received ZA (n = 13) or placebo (n = 12). Evaluation was at baseline, 2-weeks, 4-weeks, 3-months and 6-months for assessment of LBP/leg pain intensity, disability (Oswestry-Disability-Index: ODI), health-related quality-of-life (RAND-36), and mental component summary scores (MCS). Type 2 MC at baseline (56%) were prevalent. In the ZA group, LBP intensity was lower at 4-weeks in comparison to placebo (5.1 ± 1.9 vs. 6.9 ± 1.8, p = 0.038) (minimal clinically important difference [MCID] = 1.5). LBP intensity reduced at 4-weeks and 3-months in the ZA-treated group in comparison to baseline. Although there was no difference in ODI, subscale RAND-36 metrics for physical function (p = 0.038), energy/fatigue (p = 0.040) and pain (p = 0.003) were improved at 3-months compared to placebo, with moderate significant difference for pain at 6-months (p = 0.051). Correlated MCS scores to baseline also improved at 3-months (p = 0.035) and 6-months (p = 0.028) by 6.9 and 6.8, respectively, (MCID = 3.8). A reduction in MC endplate affected area at 6-month follow-up was noted in the ZA group (-0.67 ± 0.69 cm² ), while in the placebo group no change in size was observed (0.0 ± 0.15; p = 0.041). Three subjects withdrew from the study and no long-lasting adverse events. Oral ZA was a safe and effective treatment that reduced MC volume, improved LBP symptoms and quality-of-life measures in cLBP subjects with MCs.

Participatory Ergonomics Intervention to Prevent Work Disability Among Workers with Low Back Pain: A Randomized Clinical Trial in Workplace Setting

Purpose In order to support people with low back pain (LBP) to stay at work, work arrangements are regarded important. This study aimed to evaluate the effectiveness of a workplace intervention using a participatory approach on work disability of workers with ongoing or recurrent LBP. Methods A total of 107 workers with LBP, with duration of pain for at least two consecutive weeks or recurrent pain of any duration during the last year, were randomized either to the intervention (n = 51) or control group (n = 56). The intervention included arrangements at the workplace, along with individual guidance provided by an occupational physiotherapist (OPT). The randomized intervention study used standard counselling and guidance by an OPT without workplace intervention as a comparison. Surveys were completed at baseline, and 6 and 12 months after baseline. Results There were no statistically significant differences between the intervention and control groups on the primary outcome measure, i.e. self-assessed work ability. We found no between-group differences in perceived health, self-assessed work productivity, number of sickness absence days and severity of back pain. However, there were significant positive within-group changes in the intervention group in the intensity of LBP, perceived health and the number of sickness absence days due to LBP. Conclusion Workplace arrangements are feasible using participatory ergonomics, but more quantitative and qualitative research is needed on its utilization and effectiveness among workers with LBP.

Eveningness intensifies the association between musculoskeletal pain and health-related quality of life: a Northern Finland Birth Cohort Study 1966

ABSTRACT

People with an evening (E)-type preference (ie, chronotype) experience musculoskeletal (MSK) pain and reduced health-related quality of life (HRQoL) more often than morning (M) types. Musculoskeletal pain is a well-established contributor to reduced HRQoL. This study aimed to evaluate whether eveningness amplifies the association between MSK pain and HRQoL in contrast to morningness. Questionnaire data on MSK pain dimensions (intensity, disability at work, number of pain sites [NPSs], and frequency), chronotype, covariates (sex, sufficiency of sleep duration, mental distress, and presence of coexisting diseases), and HRQoL (measured by 15D) were collected among 46-year-old individuals belonging to the Northern Finland Birth Cohort 1966 (N = 4257). Individuals without any MSK pain were excluded. General linear models were conducted to estimate the associations between chronotypes, MSK pain dimensions, and HRQoL. The interaction terms (chronotype × pain dimension) were tested in the models. There were 13% E-types and 43% M-types in the study sample. Each pain dimension and chronotype were related to HRQoL. In the sex-adjusted chronotype-specific models, the reduction in HRQoL in relation to pain appeared to be stronger among E-types than among M-types in respect to all pain dimensions. After adjustments, this was particularly seen in terms of NPS and pain frequency. Our findings suggest that eveningness intensifies the association between MSK pain and HRQoL, and, thus, they are indicative of E-types being more sensitive than M-types to the consequences of MSK pain. As such, MSK pain treatment and rehabilitation actions to improve HRQoL should be especially targeted at E-types.

Association of musculoskeletal pain with the achievement of treatment targets for type 2 diabetes among primary care patients

AIMS

To assess the association of diagnosed musculoskeletal (MS) pain (low back, neck, shoulder, and knee pain; and the number of pain sites) with the achievement of targets for glycosylated haemoglobin A1c (HbA1c), low-density-lipoprotein cholesterol (LDL), and systolic blood pressure (SBP) among primary care patients with type 2 diabetes (T2D).

METHODS

The cross-sectional study population consisted of 3478 patients with a registry-based T2D diagnosis and available registry-based data on MS pain diagnoses, covariates, and outcomes between 2016 and 2019. Logistic regression analysis was used to evaluate the study aims.

RESULTS

Overall, 22% had at least one of the four types of MS pain, and 73%, 57%, and 51% achieved the treatment targets of HbA1c, LDL, and SBP, respectively. T2D patients with or without MS pain did not differ in their achievement of T2D treatment goals. Of pain locations, low back pain was associated with higher rates of achievement of the LDL target (OR 1.29, 95% CI 1.01-1.65), but the association was attenuated in the adjusted model.

CONCLUSIONS

MS pain was relatively prevalent among primary care patients with T2D, but did not influence the achievement of T2D treatment goals.

Learning-based fully automated prediction of lumbar disc degeneration progression with specified clinical parameters and preliminary validation

BACKGROUND

Lumbar disc degeneration (LDD) may be related to aging, biomechanical and genetic factors. Despite the extensive work on understanding its etiology, there is currently no automated tool for accurate prediction of its progression.

PURPOSE

We aim to establish a novel deep learning-based pipeline to predict the progression of LDD-related findings using lumbar MRIs.

MATERIALS AND METHODS

We utilized our dataset with MRIs acquired from 1,343 individual participants (taken at the baseline and the 5-year follow-up timepoint), and progression assessments (the Schneiderman score, disc bulging, and Pfirrmann grading) that were labelled by spine specialists with over ten years clinical experience. Our new pipeline was realized by integrating the MRI-SegFlow and the Visual Geometry Group-Medium (VGG-M) for automated disc region detection and LDD progression prediction correspondingly. The LDD progression was quantified by comparing the Schneiderman score, disc bulging and Pfirrmann grading at the baseline and at follow-up. A fivefold cross-validation was conducted to assess the predictive performance of the new pipeline.

RESULTS

Our pipeline achieved very good performances on the LDD progression prediction, with high progression prediction accuracy of the Schneiderman score (Accuracy: 90.2 ± 0.9%), disc bulging (Accuracy: 90.4% ± 1.1%), and Pfirrmann grading (Accuracy: 89.9% ± 2.1%).

CONCLUSION

This is the first attempt of using deep learning to predict LDD progression on a large dataset with 5-year follow-up. Requiring no human interference, our pipeline can potentially achieve similar predictive performances in new settings with minimal efforts.

Total, gender- and age-specific incidence rates of upper extremity nerve injuries in Finland

The aim of this study was to describe the epidemiology of nerve injuries of the upper extremity in the whole population of Finland (1998-2016). Data based on diagnosis codes were obtained from the Care Register for Health Care, including cases of median, radial, ulnar, musculocutaneous, axillary and digital nerves. Age- and gender-specific incidence rates, both crude and standardized (for the European normal population in 2011), were calculated. Our study included 13,440 patients with upper extremity nerve injury. The mean standardized annual incidence rate of any upper extremity nerve injury was 18.18 among men and 8.15 among women per 100,000 person-years over the study period. The incidence peaked among men at working age. Nerve injuries occurred most commonly in the fingers and thumb, with 5532 cases and mean standardized incidence rates per 100,000 person-years of 7.84 among men and 2.95 among women. The annual incidence did not change significantly over the study period.Level of evidence: III.

Association Between Family History of Surgically Treated Low Back Pain and Adolescent Low Back Pain

STUDY DESIGN

Cross-sectional.

OBJECTIVE

To study the associations between a family history of surgically treated low back pain (LBP) and adolescent LBP.

SUMMARY OF BACKGROUND DATA

A family history of LBP is related to adolescent LBP, but whether a family history of back surgery is relevant to adolescent LBP is not known.

METHODS

A subpopulation of the Northern Finland Birth Cohort 1986 was contacted when they were aged between 18 and 19years. The postal questionnaire asked the participants to report their LBP and a relative's (mother, father, sibling) LBP and back surgery, and to provide data on potential covariates. The association between a family history of LBP ("no family history of LBP," "family history of LBP but no surgery," and "family history of LBP and surgery") and adolescent LBP (no LBP, occasional LBP, and frequent LBP) were evaluated using logistic regression analysis with odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for sex, smoking, and psychological distress.

RESULTS

Of the 1374 adolescents in the study, 33% reported occasional LBP and 9% frequent LBP. Both the "family history of LBP but no surgery" and "family history of LBP and surgery" categories were associated with frequent LBP (adjusted OR [aOR] 2.09, 95% CI 1.38-3.16; aOR 2.23, 95% CI 1.02-4.90, respectively). Occasional LBP was associated with the "family history of LBP and surgery" category. A subgroup analysis of adolescents with a family history of LBP found no statistically significant associations between family history of back surgery and adolescent LBP.

CONCLUSION

Our findings suggest that adolescents who report a family history of LBP have higher odds of frequent LBP irrespectively of a family history of back surgery.Level of evidence: 4.

Association of lumbar disc degeneration with low back pain in middle age in the Northern Finland Birth Cohort 1966

Background

Although it has been suggested that lumbar disc degeneration (LDD) is a significant risk factor for low back pain (LBP), its role remains uncertain. Our objective was to clarify the association between LDD and LBP and whether mental distress modifies the association.

Methods

Participants of a birth cohort underwent 1.5-T lumbar magnetic resonance imaging at the age of 47. The association between the sum score of LDD (Pfirrmann classification, range 0–15) and LBP (categorized into “no pain”, “mild-to-moderate pain”, “bothersome-and-frequent pain”) was assessed using logistic regression analysis, with sex, smoking, body mass index, physical activity, occupational exposure, education, and presence of Modic changes and disc herniations as confounders. The modifying role of mental distress (according to the Hopkins Symptom Check List-25 [HSCL-25], the Beck Depression Inventory and the Generalized Anxiety Disorder Scale) in the association was analyzed using linear regression.

Results

Of the study population (n = 1505), 15.2% had bothersome and frequent LBP, and 29.0% had no LBP. A higher LDD sum score increased the odds of belonging to the “mild-to-moderate pain” category (adjusted OR corresponding to an increase of one point in the LDD sum score 1.11, 95% CI 1.04–1.18, P = 0.003) and the “bothersome-and-frequent pain” category (adjusted OR 1.20, 95% CI 1.10–1.31, P < 0.001), relative to the “no pain” category. Mental distress significantly modified the association between LDD and LBP, as a linear positive association was consistently observed among individuals without mental distress according to HSCL-25 (adjusted B 0.16, 95% CI 0.07–0.26, P < 0.001), but not among individuals with higher mental distress.

Conclusions

LDD was significantly associated with both mild-to-moderate and bothersome-and-frequent LBP. However, the co-occurrence of mental distress diminished the association between LDD and LBP bothersomeness. Our results strongly suggest that mental symptoms affect the pain experience.

Weight-Related and Personal Risk Factors of Carpal Tunnel Syndrome in the Northern Finland Birth Cohort 1966

BACKGROUND

Excess body mass is a risk factor for carpal tunnel syndrome (CTS), but the mechanisms of this are unclear. This study aimed to evaluate the association between CTS and personal risk factors of body mass index (BMI), waist circumference and waist-to-hip ratio (WHR).

METHODS

The study sample consisted of the Northern Finland Birth Cohort 1966 (n = 9246). At the age of 31 in 1997 and at the age of 46 in 2012, the participants underwent a clinical examination. Cohort A consisted of complete cases with a follow-up from 1997 to 2012 (n = 4701), and Cohort B was followed up from 2012 to 2018 (n = 4548). The data on diagnosed CTS were provided by the Care Register for Health Care until the end of 2018.

RESULTS

After an adjustment for confounding factors, BMI was associated with CTS among women (hazard ratio (HR) 1.47, 95% Cl 0.98-2.20 for overweight women and HR 2.22, 95% Cl 1.29-3.83 for obese women) and among both sexes combined (HR 1.35 95% Cl 0.96-1.90 for overweight and HR 1.98 95% Cl 1.22-3.22 for obese participants). Neither waist circumference nor WHR was associated with CTS.

CONCLUSIONS

BMI is an independent risk factor for CTS and is more relevant for estimating the increased risk of CTS due to excess body mass than waist circumference or WHR.

Chronotypes and disabling musculoskeletal pain: A Finnish birth cohort study

BACKGROUND

It has been suggested that chronotype, the individual preference for 24-hour circadian rhythms, influences health. Sleep problems and mental distress are among the greatest risk factors for musculoskeletal (MS) pain. The aims of this study were first, to explore the associations between chronotypes and MS pain, with special reference to disabling MS pain, and second, to test whether mental distress and insomnia have a modifying role in the associations between chronotypes and MS pain.

METHODS

The dataset of 4,961 individuals was composed of Northern Finns surveyed on MS pain, chronotypes, and confounding factors (sex, insomnia, sleep duration, smoking, mental distress, occupational status, education level, and number of co-existing diseases) at 46 years. The relationships between chronotypes (evening [E], intermediate [I], and morning [M]) and MS pain were evaluated using multinomial logistic regression. To address the second aim, we included an interaction term (chronotype*mental distress, chronotype*insomnia) in the logistic model.

RESULTS

Compared to the M-types, both the E- and I-types had increased odds of suffering 'disabling pain' in the unadjusted model (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.37-2.33; OR 1.54, 95% CI 1.29-1.84, respectively). However, the association remained statistically significant only after adjusting for all covariates among the I-types (OR 1.39, 95% CI 1.15-1.67). Neither mental distress nor insomnia was found to modify the chronotype-MS pain association.

CONCLUSIONS

The results highlight the importance of chronotypes for individuals' MS health but suggest the presence of confounding factors in the interplay between these factors.

The Association Between Different Trajectories of Low Back Pain and Degenerative Imaging Findings in Young Adult Participants Within The Raine Study

STUDY DESIGN

Case-control study.

OBJECTIVE

Investigate the association between lumbar spine magnetic resonance imaging (MRI) findings and 5-year trajectories of low back pain (LBP) in young Australian adults.

SUMMARY OF BACKGROUND DATA

The association between lumbar spine imaging findings and LBP remains unclear due to important limitations of previous research, such as a lack of clearly defined LBP phenotypes and inadequate controlling for age, which may substantially affect the association.

METHODS

Seventy-eight "case" participants with a previously identified "consistent high disabling LBP" trajectory from age 17 to 22 years and 78 "control" participants from a trajectory with consistently low LBP over the same time period, matched for sex, body mass index, physical activity levels, and work physical demands, were identified from Gen2 Raine Study participants. At age 27, participants underwent a standardized lumbar MRI scan, from which 14 specific MRI phenotypes were identified. Primary analyses used unconditional logistic regression, adjusting for covariates used in the matching process, to investigate the relationship between presence of each imaging finding and being a case or control. Secondary analyses explored those relationships based on the number of spinal levels with each MRI finding.

RESULTS

The odds for being a case compared with a control were higher in those with disc degeneration (Pfirrmann grade ≥ 3; OR = 3.21, 95% CI: 1.60-6.44; P = 0.001) or those with a herniation (OR = 1.90, 95% CI: 0.96-3.74; P - 0.065). We also found that the association became substantially stronger when either disc degeneration or herniation was present at two or more spinal levels (OR = 5.56, 95% CI: 1.97-15.70; P = 0.001, and OR = 5.85, 95% CI: 1.54-22.25; P = 0.009, respectively). The other investigated MRI findings were not associated with greater odds of being a case.

CONCLUSION

Lumbar disc degeneration and herniation may be important contributors to disabling LBP in young adults. Further investigation of their potential prognostic and causal roles is indicated.Level of Evidence: 4.

A definition and clinical grading of Modic changes

To provide an up-to-date description of knowledge and pitfalls related to the classification, definition and grading of Modic changes (MC) visualized on magnetic resonance imaging (MRI). State-of-the-art review of current knowledge regarding the definition and grading of MC on MRI. MC on MRI have been reported to be associated with low back pain and disability. However, previous studies have shown heterogeneous results in regards to the impact of MC and its clinical relevance in patients with back pain. MC is a term used with considerable variation in the literature. No strict definition has been provided previously, this has contributed to varying diagnostic inclusion criteria, heterogeneous study populations, and discrepancy in results. A definition of MC and a proposal for grading is provided in this state-of-the-art review. MC are important, clinically relevant findings. However, issues with the nomenclature, definition and grading of these changes need to be addressed. Our current review highlights relevant issues related to MC, and provides a definition and grading score for the term MC that includes the Modic type and the extent of vertebral body involvement. Future studies should seek to validate the MC grading score in clinically relevant populations.

The Association of Lumbosacral Transitional Vertebrae with Low Back Pain and Lumbar Degenerative Findings in MRI: A Large Cohort Study

STUDY DESIGN

A cross-sectional study of the Northern Finland Birth Cohort 1966 (NFBC1966).

OBJECTIVE

To evaluate the association of lumbosacral transitional vertebrae (LSTV) with low back pain (LBP) and associated degenerative findings using magnetic resonance (MR) imaging.

SUMMARY OF BACKGROUND DATA

LSTV is a common finding with a prevalence of 10% to 29%. LSTV causes biomechanical alterations leading to accelerated lumbar degeneration. However, its association with degenerative findings on MRI and LBP is unclear.

METHODS

One thousand four hundred sixty eight lumbar spine MRI scans from the NFBC1966 acquired at a mean age of 47 years were assessed for the presence of LSTV and degenerative changes. Castellvi classification was utilized to identify LSTV anatomy. Additionally, 100 controls without LSTV were collected. Self-reported LBP with a duration of more than 30 days in the past year was deemed clinically relevant. For the statistical analyses, chi square test, independent samples t test and multinomial logistic regression analyses were used.

RESULTS

LSTV was found in 310 (21.1%) subjects. After adjusting for age, sex, and disc degeneration (DD) sum, subjects with Castellvi type III reported prolonged LBP significantly more frequently than the controls (odds ratio [OR] = 8.9, P = 0.001). We observed a higher prevalence of facet degeneration (FD) at all levels from L3/L4 to L5/S1 in type I, and L3/L4 to L4/L5 in types II-IV. DD was more prevalent at L4/L5 in types II-IV. Disc protrusion/extrusion occurred more frequently at L3/L4 and L4/L5 in type II, and at L3/L4 in type III. Castellvi type II had a higher prevalence of type 1 Modic changes at levels from L3/L4 to L4/L5.

CONCLUSION

LSTVs were a common finding within this study, and Castellvi type III LSTVs were associated with LBP. Degenerative findings were associated with LSTV anatomy and occurred more commonly above the transitional level.Level of Evidence: 3.

Are Morphometric and Biomechanical Characteristics of Lumbar Multifidus Related to Pain Intensity or Disability in People With Chronic Low Back Pain After Considering Psychological Factors or Insomnia?

INTRODUCTION

Lumbar multifidus muscle (LMM) dysfunction is thought to be related to pain and/or disability in people with chronic low back pain (CLBP). Although psychosocial factors play a major role in pain/disability, they are seldom considered as confounders in analyzing the association between LMM and CLBP.

OBJECTIVES

This study aimed to determine: (1) differences in psychological factors, insomnia, and LMM characteristics between people with and without CLBP; (2) associations between psychological factors, insomnia, or LMM characteristics and low back pain (LBP) intensity or LBP-related disability in people with CLBP; and (3) whether LMM characteristics are related to LBP symptoms in people with CLBP after considering confounders.

METHODS

Seventy-eight volunteers with CLBP and 73 without CLBP provided sociodemographic information, filled the 11-point numeric pain rating scale and Roland-Morris disability questionnaire (RMDQ). They completed the Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), Fear Avoidance Belief Questionnaire (FAB), and Insomnia Severity Index Scale (ISI). Resting and contracted thickness of LMM at L4-S1 levels were measured from brightness-mode ultrasound images. Percent thickness changes of LMM at L4-S1 levels during contraction were calculated. Resting LMM stiffness at L4-S1 was measured by shear wave elastography. Associations among LMM, psychosocial or insomnia parameters and clinical outcomes were analyzed by univariate and multivariate analyses.

RESULTS

People with CLBP demonstrated significantly higher LBP-intensity, RMDQ, HADS, FAB, PCS, and ISI scores than asymptomatic controls (p < 0.05). The former also had significantly smaller percent thickness changes of LMM at L4/L5 during contraction. LBP-intensity was positively related to scores of PCS-total, PCS-helplessness, FAB-total, FAB-work, and ISI in people with CLBP (p < 0.05). RMDQ scores were positively associated with the scores of HADS-total, HADS-depression, PCS-total, FAB-total, FAB-physical activity, PCS-helplessness, and ISI in people with CLBP (p < 0.05). FAB-work and ISI scores together explained 24% of LBP-intensity. FAB-total scores alone explained 34% of variance of LBP-related disability in people with CLBP.

CONCLUSION

More fear-avoidance belief or insomnia is related to greater LBP-intensity and/or LBP-related disability in people with CLBP. Although people with CLBP were thought to have aberrant LMM morphometry/function, no LMM characteristics were related to LBP-intensity or LBP-related disability after considering other confounders.

Associations of Metabolic Syndrome and Its Components with the Risk of Incident Knee Osteoarthritis Leading to Hospitalization: A 32-Year Follow-up Study

OBJECTIVES

To examine whether metabolic syndrome or its individual components predict the risk of incident knee osteoarthritis (OA) in a prospective cohort study during a 32-year follow-up period.

DESIGN

The cohort consisted of 6274 participants of the Mini-Finland Health Survey, who were free from knee OA and insulin-treated diabetes at baseline. Information on the baseline characteristics, including metabolic syndrome components, hypertension, elevated fasting glucose, elevated triglycerides, reduced high-density lipoprotein, and central obesity were collected during a health examination. We drew information on the incidence of clinical knee OA from the national Care Register for Health Care. Of the participants, 459 developed incident knee OA. In our full model, age, gender, body mass index, history of physical workload, smoking history, knee complaint, and previous injury of the knee were entered as potential confounding factors.

RESULTS

Having metabolic syndrome at baseline was not associated with an increased risk of incident knee OA. In the full model, the hazard ratio for incident knee OA for those with metabolic syndrome was 0.76 (95% confidence interval [0.56, 1.01]). The number of metabolic syndrome components or any individual component did not predict an increased risk of knee OA. Of the components, elevated plasma fasting glucose was associated with a reduced risk of incident knee OA (hazard ratio 0.71, 95% confidence interval [0.55, 0.91]).

CONCLUSIONS

Our findings do not support the hypothesis that metabolic syndrome or its components increase the risk of incident knee OA. In fact, elevated fasting glucose levels seemed to predict a reduced risk.

T2 -weighted magnetic resonance imaging texture as predictor of low back pain: A texture analysis-based classification pipeline to symptomatic and asymptomatic cases

Low back pain is a very common symptom and the leading cause of disability throughout the world. Several degenerative imaging findings seen on magnetic resonance imaging are associated with low back pain but none of them is specific for the presence of low back pain as abnormal findings are prevalent among asymptomatic subjects as well. The purpose of this population-based study was to investigate if more specific magnetic resonance imaging predictors of low back pain could be found via texture analysis and machine learning. We used this methodology to classify T₂ -weighted magnetic resonance images from the Northern Finland Birth Cohort 1966 data to symptomatic and asymptomatic groups. Lumbar spine magnetic resonance imaging was performed using a fast spin-echo sequence at 1.5 T. Texture analysis pipeline consisting of textural feature extraction, principal component analysis, and logistic regression classifier was applied to the data to classify them into symptomatic (clinically relevant pain with frequency ≥30 days and intensity ≥6/10) and asymptomatic (frequency ≤7 days, intensity ≤3/10, and no previous pain episodes in the follow-up period) groups. Best classification results were observed applying texture analysis to the two lowest intervertebral discs (L4-L5 and L5-S1), with accuracy of 83%, specificity of 83%, sensitivity of 82%, negative predictive value of 94%, precision of 56%, and receiver operating characteristic area-under-curve of 0.91. To conclude, textural features from T₂ -weighted magnetic resonance images can be applied in low back pain classification.

Integrative analysis of metabolomic, genomic, and imaging-based phenotypes identify very-low-density lipoprotein as a potential risk factor for lumbar Modic changes

PURPOSE

Modic changes (MC) on magnetic resonance imaging (MRI) have been associated with the development and severity of low back pain (LBP). The etiology of MC remains elusive, but it has been suggested that altered metabolism may be a risk factor. As such, this study aimed to identify metabolomic biomarkers for MC phenotypes of the lumbar spine via a combined metabolomic-genomic approach.

METHODS

A population cohort of 3,584 southern Chinese underwent lumbar spine MRI. Blood samples were genotyped with single-nucleotide polymorphisms (SNP) arrays (n = 2,482) and serum metabolomics profiling using magnetic resonance spectroscopy (n = 757), covering 130 metabolites representing three molecular windows, were assessed. Genome-wide association studies (GWAS) were performed on each metabolite, to construct polygenic scores for predicting metabolite levels in subjects who had GWAS but not metabolomic data. Associations between predicted metabolite levels and MC phenotypes were assessed using linear/logistic regression and least absolute shrinkage and selection operator (LASSO). Two-sample Mendelian randomization analysis tested for causal relationships between metabolic biomarkers and MC.

RESULTS

20.4% had MC (10.6% type 1, 67.2% type 2, 22.2% mixed types). Significant MC metabolomic biomarkers were mean diameter of very-low-density lipoprotein (VLDL)/low-density lipoprotein (LDL) particles and cholesterol esters/phospholipids in large LDL. Mendelian randomization indicated that decreased VLDL mean diameter may lead to MC.

CONCLUSIONS

This large-scale study is the first to address metabolomics in subject with/without lumbar MC. Causality studies implicate VLDL related to MC, noting a metabolic etiology. Our study substantiates the field of "spino-metabolomics" and illustrates the power of integrating metabolomics-genomics-imaging phenotypes to discover biomarkers for spinal disorders, paving the way for more personalized spine care for patients.

Patient education booklet to support evidence-based low back pain care in primary care - a cluster randomized controlled trial

BACKGROUND

Inappropriate imaging and low-value care for low back pain (LBP) are common. A new patient-education booklet was created to overcome identified barriers to the delivery of recommended care, including the use of inappropriate imaging. Our aim was to assess the effectiveness of this booklet as part of primary care for LBP patients in comparison to usual care.

METHODS

A cluster-randomized trial was performed. The intervention involved providing practitioners with the new patient-education booklet and a 30-min training session on its use. The booklet was provided during the clinical consult to all consenting LBP patients in the intervention group. Primary outcomes were the proportion of patients presenting with LBP who underwent imaging examinations during the first three months of follow-up and PROMIS PF-20 (Patient-Reported Outcomes Measurement Information System, 20-item physical functioning short form) change between baseline and three-month follow-up. Secondary outcomes, including sick leave and imaging examinations at 12 months, were investigated. Logistic regression using GEE-estimation was used for dichotomous outcomes, Poisson regression using GEE-estimation for count outcomes, and linear mixed models for continuous outcomes.

RESULTS

Using the patient education booklet appeared to substantially reduce the proportion of LBP patients who underwent an imaging examination at three months, but the result was not statistically significant (OR 0.57, 95% confidence interval (Cl) 0.27 to 1.22). At 12 months, the effect was slightly larger and statistically significant (OR 0.50, 95%Cl 0.30 to 0.83, p = 0.008). No difference was observed in the PROMIS PF-20 T-score change between baseline and 3 months or 12 months (p = 0.365 and p = 0.923, respectively). The number of sick leave days in the intervention group was less than that in the control group at 3 months (RR 0.47, 95%Cl 0.26 to 0.83, p = 0.010) and at 12 months (RR 0.36, 95%Cl 0.18 to 0.72, p = 0.004).

CONCLUSIONS

The booklet appeared to be effective in reducing the proportion of LBP patients who underwent imaging examinations over 12 months. The intervention had no discernible effect on the PROMIS PF20 T-score change. The number of sick leave days was substantially lower in the intervention group.

TRIAL REGISTRATION

ISRCTN, ISRCTN14389368 , Registered 4 April 2019-Retrospectively registered.

Modeling the Multidimensional Predictors of Multisite Musculoskeletal Pain Across Adulthood-A Generalized Estimating Equations Approach

Background: Multisite pain is commonly chronic and often lacks its initial role as a potential tissue damage signal. Chronic pain among working-age individuals is a risk for disability and imposes a major burden on health care systems and society. As effective treatments for chronic pain are largely lacking, better identification of the factors associated with pain over working years is needed. Methods: Members of the Northern Finland Birth Cohort 1966 participated in data collection at the ages of 31 (n = 4,028) and 46 (n = 3,429). Using these two time points, we performed a multivariable analysis of the association of socioeconomic, occupational, psychological and lifestyle factors (i.e., low education, living alone, low household income, unemployment, occupational physical exposures [hard physical labor, leaning forward, back twisting, constant moving, lifting loads of ≥ 1 kg], physical inactivity, regular smoking, regular drinking, overweight, and psychiatric symptoms) with the number of musculoskeletal pain sites (i.e., upper extremity, lower extremity, lower back, and the neck-shoulder region; totalling 0-4 pain sites). The data were analyzed using generalized estimating equations. Results: At the age of 31, multisite pain was reported by 72.5% of men and 78.6% of women. At the age of 46, the prevalence of multisite pain was 75.7% among men and 82.7% among women. Among men, the number of pain sites was positively associated with age (rate ratio 1.05, 95% confidence interval 1.01-1.08), low household income (1.05, 1.01-1.08), unemployment (1.13, 1.06-1.19), any occupational exposure (1.17, 1.12-1.22), regular smoking (1.06, 1.02-1.11), and psychiatric symptoms (1.21, 1.17-1.26). Among women, the number of pain sites was positively associated with age (1.06, 1.04-1.10), unemployment (1.10, 1.05-1.15), any occupational exposure (1.10, 1.06-1.13), regular smoking (1.06, 1.02-1.10), overweight (1.08, 1.05-1.11), and psychiatric symptoms (1.19, 1.15-1.22); living alone was negatively associated with the number of pain sites (0.95, 0.91-0.99). Conclusion: Of the studied predictors, psychiatric symptoms, occupational physical exposures and unemployment were most strongly associated with multisite pain among both sexes. The results of this study deepen the understanding of the underlying factors of and comorbidities behind multisite pain, and help develop pain relief and rehabilitation strategies for working-age individuals with multisite pain.

Does Motor Control Exercise Restore Normal Morphology of Lumbar Multifidus Muscle in People with Low Back Pain? - A Systematic Review

Aberrant morphological changes in lumbar multifidus muscle (LMM) are prevalent among patients with low back pain (LBP). Motor control exercise (MCE) aims to improve the activation and coordination of deep trunk muscles (eg, LMM), which may restore normal LMM morphology and reduce LBP. However, its effects on LMM morphology have not been summarized. This review aimed to summarize evidence regarding the (1) effectiveness of MCE in altering LMM morphometry and decreasing LBP; and (2) relations between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Cochrane Central Register of Controlled Trials, the Physiotherapy Evidence Database, EMBASE and SPORTDiscus were searched from inception to 30 September 2020 to identify relevant randomized controlled trials. Two reviewers independently screened articles, extracted data, and evaluated risk of bias and quality of evidence. Four hundred and fifty-one participants across 9 trials were included in the review. Very low-quality evidence supported that 36 sessions of MCE were better than general physiotherapy in causing minimal detectable increases in LMM cross-sectional areas of patients with chronic LBP. Very low- to low-quality evidence suggested that MCE was similar to other interventions in increasing resting LMM thickness in patients with chronic LBP. Low-quality evidence substantiated that MCE was significantly better than McKenzie exercise or analgesics in increasing contracted LMM thickness in patients with chronic LBP. Low-quality evidence corroborated that MCE was not significantly better than other exercises in treating people with acute/chronic LBP. Low-quality evidence suggested no relation between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Collectively, while MCE may increase LMM dimensions in patients with chronic LBP, such changes may be unrelated to clinical outcomes. This raises the question regarding the role of LMM in LBP development/progression.

Assessment of construct validity of the Finnish versions of the Disabilities of Arm, Shoulder and Hand Instrument and the Michigan Hand Outcomes Questionnaire

STUDY DESIGN

Cross-sectional study.

INTRODUCTION

There is a lack of information on the measurement properties of patient-reported upper extremity instruments and their association to health-related quality of life (HRQoL).

PURPOSE OF THE STUDY

This study aimed to examine and compare the measurement properties and construct validity of the Disabilities of Arm, Shoulder, and Hand (DASH) Instrument and the Michigan Hand Questionnaire (MHQ) using a heterogeneous sample of patients with hand and wrist problems.

METHODS

Two hundred fifty consecutive patients visiting a general orthopedic outpatient clinic due to various hand/wrist problems were invited to participate in the study. A total of 193 (77%) participants provided sufficient patient-reported outcome data and were included in the analysis. Participants completed the DASH, the MHQ, the EQ-5D-3L, and pain on a visual analog scale instruments. Grip and key pinch forces were measured. Scale targeting, relatedness of demographics, and construct validity of the DASH and the MHQ were assessed.

RESULTS

Both the DASH and the MHQ had good targeting, but the DASH had wider coverage. The convergence between the DASH and the MHQ was high. The DASH was more closely related to HRQoL than the MHQ in terms of EQ-5D scores.

DISCUSSION

The DASH instrument appeared to measure hand function and disability from a perspective of HRQoL superior to the MHQ among patients with heterogeneous hand and wrist complaints.

CONCLUSION

The DASH performs well in measuring the HRQoL-related hand outcomes while the MHQ might be more specific for the affected hand.

Association of psychological distress and widespread pain with sympatoms of temporomandibular disorders and self-reported bruxism in students

Objectives

The aim of this study was to evaluate the association of psychosocial distress and widespread pain with self‐reported symptoms of temporomandibular disorders (TMD) and bruxism, in two cross‐sectional surveys in 2012 and 2016, and whether there are temporal changes in the magnitude of associations.

Materials and methods

The data were gathered from Finnish university students in 2012 and 2016. TMD symptoms were assessed with three validated questions and bruxism with one frequently used question. Psychosocial distress was assessed with the General Health Questionnaire‐12 (GHQ‐12), and widespread pain with questions of pain in the extremities, the neck or upper back, and lower back. The associations of GHQ‐12, widespread pain and background variables with TMD symptoms and bruxism were analyzed with chi‐square tests, t‐test and binary logistic regression models stratified by gender, and adjusted for age‐group, self‐reported general health/wellbeing and presence of widespread pain.

Results

Higher GHQ‐12 score and presence of widespread pain were significantly associated with TMD symptoms in both genders at both time points. The association of higher GHQ‐12 score with sleep bruxism and awake bruxism were inconsistent. In the adjusted model higher GHQ‐12 score and widespread pain were significantly related to TMD pain symptoms in both genders at both time points, and to bruxism in 2012. Between the two time points a greater variability in these associations was seen in men than in women.

Conclusions

Psychological distress and widespread pain are significant determinants in perceived TMD pain and bruxism among students. No significant temporal alterations were observed.

Association of temporomandibular disorders with pain sensitivity: A cohort study

BACKGROUND

Pain related to temporomandibular disorders (TMD) can be linked with multiple site pain (MSP), and may associate with increased pain sensitivity, more frequently among women than men. The aim of the study was to examine the associations of pressure pain threshold (PPT) and tolerance (PPTo) with TMD and associated MSP in the Northern Finland Birth Cohort 1966 (NFBC1966) study.

METHODS

Altogether 1961 NFBC1966 subjects attended clinical medical and dental examination at the Institute of Dentistry, University of Oulu in 2012-2013. Clinical examinations were carried out using a modified Diagnostic Criteria for TMD protocol (DC/TMD). MSP was defined based on questions regarding body pain sites. Additionally, PPT and PPTo were assessed using algometer measurements. Mann-Whitney U-test and Tobit regression models were used to analyse associations between TMD sub-diagnoses, MSP, PPT and PPTo, stratified by sex. Further models were adjusted with anxiety and depressive symptoms, which were assessed using Hopkins Symptom Checklist-25 (HSCL-25) and two-way interaction terms.

RESULTS

Among females, lower PPT and PPTo were associated with myalgia and arthralgia. Among males, lower PPT and PPTo were associated with MSP-linked TMD. Tobit regression analysis showed significantly lower PPT and PPTo values in the myalgia and arthralgia subgroups among female TMD subjects. Among females, disc displacement with reduction had an inverse association with PPT and PPTo. Among males, lower PPTo was associated with degenerative joint disease and MSP-linked TMD.

CONCLUSIONS

The pain regulatory mechanisms behind TMD act differently between the genders as local TMD among females and MSP-linked TMD among males were associated with pain sensitivity.

SIGNIFICANCE

The study shows that there are differences in the associations of painful TMD with pressure pain tolerance, pressure pain sensitivity and MSP between male and female subjects.