Associations among pain, disability and psychosocial factors and the predictive value of expectations on returning to work in patients who undergo lumbar disc surgery

Inhibition of miR-96-5p alleviates intervertebral disc degeneration by regulating the peroxisome proliferator-activated receptor γ/nuclear factor-kappaB pathway

BACKGROUND

Intervertebral disc degeneration (IDD) is the main pathogenesis of low back pain. MicroRNAs (miRNAs) have been found to exert regulatory function in IDD. This study aimed to investigate the effect and potential mechanism of miR-96-5p in IDD.

METHODS

In vitro cell model of IDD was established by treating human nucleus pulposus cells (HNPCs) with interleukin-1β (IL-1β). The level of peroxisome proliferator-activated receptor γ (PPARγ) was examined in the IDD cell model by Western blot and quantification real-time reverse transcription-polymerase chain reaction (qRT-PCR). The expression level of miR-96-5p was detected by RT-qPCR. Effects of PPARγ or/and PPARγ agonist on inflammatory factors, extracellular matrix (ECM), apoptosis, and nuclear factor-kappaB (NF-κB) nuclear translocation were examined through enzyme-linked immunosorbent assay (ELISA), Western blot, flow cytometry assay, and immunofluorescence staining. The Starbase database and dual luciferase reporter assay were used to predict and validate the targeting relationship between miR-96-5p and PPARγ, and rescue assay was performed to gain insight into the role of miR-96-5p on IDD through PPARγ/NF-κB signaling.

RESULTS

PPARγ expression reduced with concentration and time under IL-1β stimulation, while miR-96-5p expression showed the reverse trend (P < 0.05). Upregulation or/and activation of PPARγ inhibited IL-1β-induced the increase in inflammatory factor levels, apoptosis, degradation of the ECM, and the nuclear translocation of NF-κB (P < 0.05). MiR-96-5p was highly expressed but PPARγ was lowly expressed in IDD, while knockdown of PPARγ partially reversed remission of IDD induced by miR-96-5p downregulation (P < 0.05). MiR-96-5p promoted NF-κB entry into the nucleus but PPARγ inhibited this process.

CONCLUSION

Inhibition of miR-96-5p suppressed IDD progression by regulating the PPARγ/NF-κB pathway. MiR-96-5p may be a promising target for IDD treatment clinically.

Prospects of returning to work after lumbar spine surgery for patients considering disability pension: a nationwide study based on data from the Norwegian Registry for Spine Surgery

OBJECTIVES

To assess the odds for not returning to work (non-RTW) 1 year after treatment among patients who had applied for or were planning to apply for disability pension (DP-applicant) prior to an operation for degenerative disorders of the lumbar spine.

METHODS

This population-based cohort study from the Norwegian Registry for Spine surgery included 26 688 cases operated for degenerative disorders of the lumbar spine from 2009 to 2020. The primary outcome was RTW (yes/no). Secondary patient-reported outcome measures (PROMs) were the Oswestry Disability Index, Numeric Rating Scales for back and leg pain, EuroQoL five-dimension and the Global Perceived Effect Scale. Logistic regression analysis was used to investigate associations between being a DP-applicant prior to surgery (exposure), possible confounders (modifiers) at baseline and RTW 12 months after surgery (outcome).

RESULTS

The RTW ratio for DP-applicants was 23.1% (having applied: 26.5%, planning to apply 21.1%), compared with 78.6% among non-applicants. All secondary PROMs were more favourable among non-applicants. After adjusting for all significant confounders (low expectations and pessimism related to working capability, not feeling wanted by the employer and physically demanding work), DP-applicants with under 12 months preoperative sick leave had 3.8 (95% CI 1.8 to 8.0) higher odds than non-applicants for non-RTW 12 months after surgery. The subgroup having applied for disability pension had the strongest impact on this association.

CONCLUSION

Less than a quarter of the DP-applicants returned to work 12 months after surgery. This association remained strong, also when adjusted for the confounders as well as other covariates related RTW.

Preoperative ODI and Intake of Analgesics Predict Outcome after Lumbar Microdiskectomy: Results from a Prospective Register

BACKGROUND

 Lumbar disk herniation (LDH) typically causes leg pain and neurologic deficits, but can also be a source of low back pain (LBP). Lumbar microdiskectomy (LMD) is among the most common neurosurgical procedures to relieve radicular symptoms. It is important for both surgeon and patient to understand potential predictors of outcome after LMD. The aim of this study was to investigate if the presence and intensity of preoperative LBP, the ODI score, and analgesic intake can predict the outcome of patients undergoing LMD.

METHODS

 This is a single-center retrospective study based on the analysis of prospectively acquired data of patients in the SwissDisc Registry. A total of 685 surgeries on 640 patients who underwent standardized LMD at our institution to treat LDH were included in this study. We performed multivariable linear regression analysis to determine preoperative predictors for patient outcomes based on the Oswestry Disability Index (ODI) scores, recorded on average 39.77 (±33.77) days after surgery.

RESULTS

 Our study confirmed that surgery overall improves patient degree of disability as measured by ODI score. Following model selection using Aikake Information Criterion (AIC), we observed that higher preoperative ODI scores (β: 0.020 [95% CI: 0.008 to 0.031]) and higher number of analgesic medication usage by patients prior to surgery (β: 0.236 [95% CI: 0.057 to 0.415]) were both associated with an increased postoperative ODI score.

CONCLUSION

 LDH surgery generally improves patient degree of disability. The analysis of patients with a high preoperative ODI score and increased intake of analgesics before surgery predicted a worsening of patients' disability after LMD in this subgroup.

The prognostic value of fear-avoidance beliefs on postoperative pain and dysfunction for lumbar degenerative disk disease: a meta-analysis

The study aimed to explore the prognostic value of fear-avoidance beliefs (FABs) on postoperative pain and back-specific function for patients with lumbar degenerative disk disease (LDDD). FABs have been proven to be a predictorof pain and disability for patients with low back pain. However, whether FABs are a predictor of surgical outcomes for LDDD is a matter of debate. PubMed, Cochrane library, EMBASE, and EBSCO were searched for eligible cohort studies or secondary analyses of randomized controlled trials. Fixed-effect meta-analysis models were used to estimate odds ratios (OR) because of absent or low heterogeneity ( I ² < 50%). Subgroup analyses were conducted according to different follow-up durations. Forest plots were used for graphical representation. Six studies with a total of 829 participants were included in the meta-analyses. Risk of bias was high for three studies and moderate for the other three studies. For patients with LDDD, meta-analyses showed that FABs were a predictor of postoperative pain intensity [OR 2.88; 95% confidence interval (CI), 2.76-3.00] and back-specific function (OR 3.13; 95% CI, 3.02-3.24). Patients with FABs are less likely to report improvement in pain (OR 2.56; 95% CI, 1.73-3.86) and function (OR 2.81; 95% CI, 2.57-3.07). In conclusion, FABs were a predictor of postoperative pain and back-specific function for patients with LDDD. This prognostic value is sustained for a long period after surgery (>12 months). Clinicians are advised to initiate targeted interventions for patients with FABs at different stages after surgery. Due to the limited number and low quality of included studies, the results of this meta-analysis should be interpreted with caution.

Time to return to work after elective lumbar spine surgery

OBJECTIVE

Time to return to work (RTW) after elective lumbar spine surgery is variable and dependent on many factors including patient, work-related, and surgical factors. The primary objective of this study was to describe the time and rate of RTW after elective lumbar spine surgery. Secondary objectives were to determine predictors of early RTW (< 90 days) and no RTW in this population.

METHODS

A retrospective analysis of prospectively collected data from the multicenter Canadian Spine Outcomes and Research Network (CSORN) surgical registry was performed to identify patients who were employed and underwent elective 1- or 2-level discectomy, laminectomy, and/or fusion procedures between January 2015 and December 2019. The percentage of patients who returned to work and the time to RTW postoperatively were calculated. Predictors of early RTW and not returning to work were determined using a multivariable Cox regression model and a multivariable logistic regression model, respectively.

RESULTS

Of the 1805 employed patients included in this analysis, 71% returned to work at a median of 61 days. The median RTW after a discectomy, laminectomy, or fusion procedure was 51, 46, and 90 days, respectively. Predictors of early RTW included male gender, higher education level (high school or above), higher preoperative Physical Component Summary score, working preoperatively, a nonfusion procedure, and surgery in a western Canadian province (p < 0.05). Patients who were working preoperatively were twice as likely to RTW within 90 days (HR 1.984, 95% CI 1.680-2.344, p < 0.001) than those who were employed but not working. Predictors of not returning to work included symptoms lasting more than 2 years, an increased number of comorbidities, an education level below high school, and an active workers' compensation claim (p < 0.05). There were fourfold odds of not returning to work for patients who had not been working preoperatively (OR 4.076, 95% CI 3.087-5.383, p < 0.001).

CONCLUSIONS

In the Canadian population, 71% of a preoperatively employed segment returned to work after 1- or 2-level lumbar spine surgery. Most patients who undergo a nonfusion procedure RTW after 6 to 8 weeks, whereas patients undergoing a fusion procedure RTW at 12 weeks. Working preoperatively significantly increased the likelihood of early RTW.

Overexpression of miR-150 Inhibits the NF-κB Signal Pathway in Intervertebral Disc Degeneration through Targeting P2X7

Objective: To elaborate the mechanism of miR-150 in the regulation of the NF-κB signal pathway in intervertebral disc degeneration (IDD) by targeting P2X7. Methods: The degenerative and normal intervertebral disc tissues were collected to detect the expressions of miR-150 and P2X7. Nucleus pulposus cells were transfected and divided into different groups. Cell apoptosis was determined by flow cytometry and TUNEL staining. The expressions of IL-6, TNF-α, MMP-3, MMP-13, Cox-2, iNOS, collagen II and aggrecan, as well as NF-κB-associated proteins were measured by qRT-PCR and Western blotting. Furthermore, IDD rat models were established to validate the role of miR-150 in vivo.Results: miR-150 was down-regulated but P2X7 was up-regulated in the degenerative intravertebral disc tissues. The apoptosis of nucleus pulposus cells in the IL-1β-induced group with the transfection of miR-150 mimic and siP2X7 was significantly decreased, with reduced levels of IL-6, TNF-α, MMP-3, MMP-13, Cox-2 and iNOS, increased levels of collagen II and aggrecan, as well as decreased P2X7, p-p65/p65 and cleaved caspase-3. However, the above factors showed an opposite tendency after treatment with miR-150 inhibitor. Furthermore, the P2X7 siRNA transfection could reverse the effects caused by miR-150 inhibitor. Simultaneously, pcDNA P2X7 transfection also inhibited the function of miR-150 mimic in IL-1β-induced nucleus pulposus cells. In vivoexperiments further verified the protective role of miR-150 in IDD rats. Conclusion: miR-150 may alleviate the degeneration of the intervertebral disc partially since it could restrict the NF-κB pathway by targeting P2X7, and thereby inhibiting IL-1β-induced matrix catabolism, inflammatory responses and apoptosis of the nucleus pulposus cells.

Can pain catastrophizing be changed in surgical patients? A scoping review

Background

Catastrophizing, a coping style characterized by an exaggerated negative affect when experiencing or anticipating pain, is an important factor that adversely affects surgical outcomes. Various interventions have been attempted with the goal of reducing catastrophizing and, by extension, improving treatment outcomes. We performed a systematic review to determine whether catastrophizing can be altered in surgical patients and to present evidence for interventions aimed at reducing catastrophizing in this population.

Methods

Using a scoping design, we performed a systematic search of MEDLINE and Embase. Studies reporting original research measuring catastrophizing, before and after an intervention, on the Pain Catastrophizing Scale (PCS) or Coping Strategies Questionnaire (CSQ) were selected. Studies were assessed for quality, the nature of the intervention and the magnitude of the effect observed.

Results

We identified 47 studies that measured the change in catastrophizing score following a broad range of interventions in surgical patients, including surgery, patient education, physiotherapy, cognitive behavioural therapy, psychologist-directed therapy, nursing-directed therapy and pharmacological treatments. The mean change in catastrophizing score as assessed with the PCS ranged from 0 to –19, and that with the CSQ, from +0.07 to –13. Clinically important changes in catastrophizing were observed in 7 studies (15%).

Conclusion

Catastrophizing was observed to be modifiable with an intervention in a variety of surgical patient populations. Some interventions produced greater reductions than others, which will help direct future research in the improvement of surgical outcomes.

Can patient-reported profiles avoid unnecessary referral to a spine surgeon? An observational study to further develop the Nijmegen Decision Tool for Chronic Low Back Pain

INTRODUCTION

Chronic Low Back Pain (CLBP) is a heterogeneous condition with lack of diagnostic clarity. Therapeutic interventions show small effects. To improve outcomes by targeting interventions it is recommended to develop a triage system to surgical and non-surgical treatments based on treatment outcomes. The objective of the current study was to develop and internally validate prognostic models based on pre-treatment patient-reported profiles that identify patients who either respond or do not respond to two frequently performed treatments (lumbar spine surgery and multidisciplinary pain management program).

METHODS

A consecutive cohort study in a secondary referral spine center was performed. The study followed the recommendations of the PROGRESS framework and was registered in the Dutch Trial Register (NTR5946). Data of forty-seven potential pre-consultation (baseline) indicators predicting 'response' or 'non-response' at one-year follow-up for the two treatments were obtained to develop and validate four multivariable logistic regression models. The source population consisted of 3,410 referred CLBP-patients. Two treatment cohorts were defined: elective 'spine surgery' (n = 217 [6.4%]) and multidisciplinary bio-psychosocial 'pain management program' (n = 171 [5.0%]). Main inclusion criteria were age ≥18, CLBP (≥6 months), and not responding to primary care treatment. The primary outcome was functional ability: 'response' (Oswestry Disability Index [ODI] ≤22) and 'non-response' (ODI ≥41).

RESULTS

Baseline indicators predictive of treatment outcome were: degree of disability (all models), ≥2 previous spine surgeries, psychosocial complaints, age (onset <20 or >50), and patient expectations of treatment outcomes. The explained variances were low for the models predicting response and non-response to pain management program (R2 respectively 23% and 26%) and modest for surgery (R2 30% and 39%). The overall performance was acceptable (c-index; 0.72-0.83), the model predicting non-response to surgery performed best (R2 = 39%; c-index = 0.83).

CONCLUSION

This study was the first to identify different patient-reported profiles that predict response to different treatments for CLBP. The model predicting 'non-response' to elective lumbar spine surgery performed remarkably well, suggesting that referrals of these patients to a spine surgeon could be avoided. After external validation, the patient-reported profiles could potentially enhance timely patient triage to the right secondary care specialist and improve decision-making between clinican and patient. This could lead to improved treatment outcomes, which results in a more efficient use of healthcare resources.

Multidimensional long-term outcome analysis after single-level lumbar microdiscectomy: a retrospective single-centre study

OBJECTIVE

To present multidimensional long-term results after mono-segmental microdiscectomy for lumbar disc herniation (LDH) in a large adult cohort treated at a tertiary care centre.

METHODS

Retrospective study design with Oswestry Disability Index (ODI) questionnaire employed at follow-up. All patients undergoing surgical treatment for single-level LDH between 2003 and 2009 were identified. Electronic patient records and imaging data were analysed.

RESULTS

A total of 939 patients underwent single-level lumbar MD at our institution. Three hundred and seven complete ODI forms (32.7%) were returned at a median follow-up of 48 months. Mean ODI score was 24.04, and mean age was 58 years. Females reported slightly higher ODI scores (25.52 vs. 22.68). Age and ODI score showed statistically significant correlation. Early surgery yielded lower ODI scores with patients faring significantly worse if symptoms persisted for a year or longer (one-way ANOVA, p < 0.001). ODI scores increased sharply even among those operated later than 1 week after symptom onset. Sequestered herniations were associated with significantly lower ODI scores than contained discs on MRI (21.96 vs. 39.89). Surgical complications occurred in 17 cases (5.6%), 82 patients (26.7%) required additional surgery, 58 (18.9%) of those for recurrent disc herniations.

CONCLUSION

Our findings suggest better outcomes with early surgical treatments. Time limits for conservative treatments should be set to avoid the chronification of pain and the worse overall outcomes that go along with belated surgery. Particularly in those with acute onset of pain, sequestered herniations and only mild degrees of immobilization good outcomes are common and surgical treatment appears best if indicated early.

An analysis from the Quality Outcomes Database, Part 2. Predictive model for return to work after elective surgery for lumbar degenerative disease

OBJECTIVE

Current costs associated with spine care are unsustainable. Productivity loss and time away from work for patients who were once gainfully employed contributes greatly to the financial burden experienced by individuals and, more broadly, society. Therefore, it is vital to identify the factors associated with return to work (RTW) after lumbar spine surgery. In this analysis, the authors used data from a national prospective outcomes registry to create a predictive model of patients’ ability to RTW after undergoing lumbar spine surgery for degenerative spine disease.

METHODS

Data from 4694 patients who underwent elective spine surgery for degenerative lumbar disease, who had been employed preoperatively, and who had completed a 3-month follow-up evaluation, were entered into a prospective, multicenter registry. Patient-reported outcomes—Oswestry Disability Index (ODI), numeric rating scale (NRS) for back pain (BP) and leg pain (LP), and EQ-5D scores—were recorded at baseline and at 3 months postoperatively. The time to RTW was defined as the period between operation and date of returning to work. A multivariable Cox proportional hazards regression model, including an array of preoperative factors, was fitted for RTW. The model performance was measured using the concordance index (c-index).

RESULTS

Eighty-two percent of patients (n = 3855) returned to work within 3 months postoperatively. The risk-adjusted predictors of a lower likelihood of RTW were being preoperatively employed but not working at the time of presentation, manual labor as an occupation, worker’s compensation, liability insurance for disability, higher preoperative ODI score, higher preoperative NRS-BP score, and demographic factors such as female sex, African American race, history of diabetes, and higher American Society of Anesthesiologists score. The likelihood of a RTW within 3 months was higher in patients with higher education level than in those with less than high school–level education. The c-index of the model’s performance was 0.71.

CONCLUSIONS

This study presents a novel predictive model for the probability of returning to work after lumbar spine surgery. Spine care providers can use this model to educate patients and encourage them in shared decision-making regarding the RTW outcome. This evidence-based decision support will result in better communication between patients and clinicians and improve postoperative recovery expectations, which will ultimately increase the likelihood of a positive RTW trajectory.