Effectiveness and cost-effectiveness of an individualised, progressive walking and education intervention for the prevention of low back pain recurrence in Australia (WalkBack): a randomised controlled trial.

BACKGROUND: Recurrence of low back pain is common and a substantial contributor to the disease and economic burden of low back pain. Exercise is recommended to prevent recurrence, but the effectiveness and cost-effectiveness of an accessible and low-cost intervention, such as walking, is yet to be established. We aimed to investigate the clinical effectiveness and cost-effectiveness of an individualised, progressive walking and education intervention to prevent the recurrence of low back pain. METHODS: WalkBack was a two-armed, randomised controlled trial, which recruited adults (aged 18 years or older) from across Australia who had recently recovered from an episode of non-specific low back pain that was not attributed to a specific diagnosis, and which lasted for at least 24 h. Participants were randomly assigned to an individualised, progressive walking and education intervention facilitated by six sessions with a physiotherapist across 6 months or to a no treatment control group (1:1). The randomisation schedule comprised randomly permuted blocks of 4, 6, and 8 and was stratified by history of more than two previous episodes of low back pain and referral method. Physiotherapists and participants were not masked to allocation. Participants were followed for a minimum of 12 months and a maximum of 36 months, depending on the date of enrolment. The primary outcome was days to the first recurrence of an activity-limiting episode of low back pain, collected in the intention-to-treat population via monthly self-report. Cost-effectiveness was evaluated from the societal perspective and expressed as incremental cost per quality-adjusted life-year (QALY) gained. The trial was prospectively registered (ACTRN12619001134112). FINDINGS: Between Sept 23, 2019, and June 10, 2022, 3206 potential participants were screened for eligibility, 2505 (78%) were excluded, and 701 were randomly assigned (351 to the intervention group and 350 to the no treatment control group). Most participants were female (565 [81%] of 701) and the mean age of participants was 54 years (SD 12). The intervention was effective in preventing an episode of activity-limiting low back pain (hazard ratio 0·72 [95% CI 0·60-0·85], p=0·0002). The median days to a recurrence was 208 days (95% CI 149-295) in the intervention group and 112 days (89-140) in the control group. The incremental cost per QALY gained was AU$7802, giving a 94% probability that the intervention was cost-effective at a willingness-to-pay threshold of $28 000. Although the total number of participants experiencing at least one adverse event over 12 months was similar between the intervention and control groups (183 [52%] of 351 and 190 [54%] of 350, respectively, p=0·60), there was a greater number of adverse events related to the lower extremities in the intervention group than in the control group (100 in the intervention group and 54 in the control group). INTERPRETATION: An individualised, progressive walking and education intervention significantly reduced low back pain recurrence. This accessible, scalable, and safe intervention could affect how low back pain is managed. FUNDING: National Health and Medical Research Council, Australia.

How is postoperative pain after hip and knee replacement managed? An analysis of two large hospitals in Australia.

BACKGROUND: Multimodal analgesia regimens are recommended for the postoperative period after hip and knee replacement surgeries. However, there are no data on practice patterns for analgesic use in the immediate postoperative period after hip and knee replacements in Australia. OBJECTIVES: To describe analgesic prescribing patterns in the inpatient postoperative phase for patients undergoing hip and knee replacement. METHODS: Retrospective study of electronic medical record data from two major hospitals in Sydney, Australia. We identified analgesic medication prescriptions for all patients aged 18 years and older who underwent hip or knee replacement surgery in 2019. We extracted data on pain medications prescribed while in the ward up until discharge. These were grouped into distinct categories based on the Anatomical Therapeutic Chemical classification. We described the frequency (%) of pain medications used by category and computed the average oral morphine equivalent daily dose (OMEDD) during hospitalisation. RESULTS: We identified 1282 surgeries in 1225 patients. Patients had a mean (SD) age of 69 (11.8) years; most (57.1%) were female. Over 99% of patients were prescribed opioid analgesics and paracetamol during their hospital stay. Most patients (61.4%) were managed with paracetamol and opioids only. The most common prescribed opioid was oxycodone (87.3% of patients). Only 19% of patients were prescribed nonsteroidal anti-inflammatories (NSAIDs). The median (IQR) average daily OMEDD was 50.2 mg (30.3-77.9). CONCLUSION: We identified high use of opioids analgesics as the main strategies for pain control after hip and knee replacement in hospital. Other analgesics were much less frequently used, such as NSAIDs, and always in combination with opioids and paracetamol.

Paracetamol Combination Therapy for Back Pain and Osteoarthritis: A Systematic Review and Meta-Analyses.

BACKGROUND AND OBJECTIVE: Although paracetamol (acetaminophen) combined with other analgesics can reduce pain intensity in some pain conditions, its effectiveness in managing low back pain and osteoarthritis is unclear. This systematic review investigated whether paracetamol combination therapy is more effective and safer than monotherapy or placebo in low back pain and osteoarthritis. METHODS: Online database searches were conducted for randomised trials that evaluated paracetamol combined with another analgesic compared to a placebo or the non-paracetamol ingredient in the combination (monotherapy) in low back pain and osteoarthritis. The primary outcome was a change in pain. Secondary outcomes were (serious) adverse events, changes in disability and quality of life. Follow-up was immediate (≤ 2 weeks), short (> 2 weeks but ≤ 3 months), intermediate (> 3 months but < 12 months) or long term (≥ 12 months). A random-effects meta-analysis was conducted. Risk of bias was assessed using the original Cochrane tool, and quality of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: Twenty-two studies were included. Pain was reduced with oral paracetamol plus a non-steroidal anti-inflammatory drug (NSAID) at immediate term in low back pain (paracetamol plus ibuprofen vs ibuprofen [mean difference (MD) - 6.2, 95% confidence interval (CI) -10.4 to -2.0, moderate evidence]) and in osteoarthritis (paracetamol plus aceclofenac vs aceclofenac [MD - 4.7, 95% CI - 8.3 to - 1.2, moderate certainty evidence] and paracetamol plus etodolac vs etodolac [MD - 15.1, 95% CI - 18.5 to - 11.8; moderate certainty evidence]). Paracetamol plus oral tramadol reduced pain compared with placebo at intermediate term for low back pain (MD - 11.7, 95% CI - 19.2 to - 4.3; very low certainty evidence) and osteoarthritis (MD - 6.8, 95% CI - 12.7 to -0.9; moderate certainty evidence). Disability scores improved in half the comparisons. Quality of life was infrequently measured. All paracetamol plus NSAID combinations did not increase the risk of adverse events compared to NSAID monotherapy. CONCLUSIONS: Low-to-moderate quality evidence supports the oral use of some paracetamol plus NSAID combinations for short-term pain relief with no increased risk of harm for low back pain and osteoarthritis compared to its non-paracetamol monotherapy comparator.

Optimization of lipid nanoparticles for gene editing of the liver via intraduodenal delivery.

Lipid nanoparticles (LNPs) have recently emerged as successful gene delivery platforms for a diverse array of disease treatments. Efforts to optimize their design for common administration methods such as intravenous injection, intramuscular injection, or inhalation, revolve primarily around the addition of targeting ligands or the choice of ionizable lipid. Here, we employed a multi-step screening method to optimize the type of helper lipid and component ratios in a plasmid DNA (pDNA) LNP library to efficiently deliver pDNA through intraduodenal delivery as an indicative route for oral administration. By addressing different physiological barriers in a stepwise manner, we down-selected effective LNP candidates from a library of over 1000 formulations. Beyond reporter protein expression, we assessed the efficiency in non-viral gene editing in mouse liver mediated by LNPs to knockdown PCSK9 and ANGPTL3 expression, thereby lowering low-density lipoprotein (LDL) cholesterol levels. Utilizing an all-in-one pDNA construct with Strep. pyogenes Cas9 and gRNAs, our results showcased that intraduodenal administration of selected LNPs facilitated targeted gene knockdown in the liver, resulting in a 27% reduction in the serum LDL cholesterol level. This LNP-based all-in-one pDNA-mediated gene editing strategy highlights its potential as an oral therapeutic approach for hypercholesterolemia, opening up new possibilities for DNA-based gene medicine applications.

Opioids for Acute Musculoskeletal Pain: A Systematic Review with Meta-Analysis.

OBJECTIVE: To evaluate the efficacy of opioids for people with acute musculoskeletal pain against placebo. STUDY DESIGN: Systematic review and meta-analyses of randomised, placebo-controlled trials of opioid analgesics for acute musculoskeletal pain in any setting. The primary outcomes were pain and disability at the immediate timepoint (< 24 h). DATA SOURCES: Multiple databases were searched from their inception to February 22nd, 2023. DATA SYNTHESIS: Continuous outcomes were converted to a 0-100 scale. Dichotomous outcomes were presented as risk differences. Risk of bias and certainty of evidence was assessed. RESULTS: We located 17 trials (1 intravenous and 16 oral route of administration). For adults, high certainty evidence from 11 comparisons shows that oral opioids provide small benefits relative to placebo in the immediate term for pain (mean difference [MD] - 8.8 95% confidence interval [CI] - 12.0 to - 5.6). For disability, the difference is uncertain (MD - 6.2, 95% CI - 17.8 to 5.4). Opioid groups were at higher risk of adverse events (MD 14.3%, 95% CI 8.3-20.4%, very low certainty). There was moderate certainty evidence of a large effect of IV morphine on sciatica pain (MD -42.5, 95% CI - 49.9 to - 35.1, n = 197, 1 study). In paediatric populations, moderate certainty evidence from 3 trials shows that oral opioids probably do not provide benefit beyond that of placebo for pain (MD 6.1, 95% CI - 1.7 to 12.8) and there was no evidence for disability. There was low certainty evidence that there may be no difference in adverse events (MD 10.4%, 95% CI - 0.6 to 21.4%). DISCUSSION: Intravenous morphine likely offers benefits, but oral opioids may not provide clinically meaningful benefits. PROSPERO REGISTRATION: CRD42021249346.

Compliance with Australian Orthopaedic Association guidelines does not reduce the risk of venous thromboembolism after total hip and knee arthroplasty.

Preventing avoidable venous-thrombo-embolism (VTE) is a priority to improve patient and service outcomes after total hip and total knee arthroplasty (THA, TKA), but compliance with relevant clinical guidelines varies. This study aims to determine the degree to which prophylaxis was compliant with Australian Orthopaedic Association (AOA) VTE prophylaxis guidelines and whether non-compliance is associated with increased risk of VTE. A prospective multi-centre cohort study of adults with osteoarthritis undergoing primary TKA/THA was completed at 19 high-volume public and private hospitals. Data were collected prior to surgery and for one-year post-surgery. Logistic regression was undertaken to explore associations between non-compliance with AOA VTE prophylaxis guidelines and symptomatic 90-day VTE outcomes. Data were analysed for 1838 participants from 19 sites. The rate of non-compliance with all clinical guideline recommendations was 20.1% (N = 369), with 14.1% (N = 259) non-compliance for risk-stratified prophylaxis, 35.8% (N = 658) for duration, and 67.8% (N = 1246) for other general recommendations. Symptomatic VTE was experienced up to 90-days post-surgery by 48 people (2.6%). Overall guideline non-compliance (AOR = 0.93, 95%CI = 0.4 to 1.3, p = 0.86) was not associated with a lower risk of symptomatic 90-day VTE. Results were consistent when people with high bleeding risk were excluded (AOR = 0.94, 95%CI = 0.44 to 2.34, p = 0.89). Non-compliance with the AOA VTE prophylaxis guidelines was not associated with risk of 90-day VTE after arthroplasty. This counterintuitive finding is concerning and necessitates a rigorous review of the AOA VTE prevention clinical guideline.

Context matters: using an Evidence to Decision (EtD) framework to develop and encourage uptake of opioid deprescribing guideline recommendations at the point-of-care.

OBJECTIVES: To describe the development and use of an Evidence to Decision (EtD) framework when formulating recommendations for the Evidence-Based Clinical Practice Guideline for Deprescribing Opioid Analgesics. STUDY DESIGN AND SETTING: Evidence was derived from an overview of systematic reviews and qualitative studies conducted with healthcare professionals and people who take opioids for pain. A multidisciplinary guideline development group conducted extensive EtD framework review and iterative refinement to ensure that guideline recommendations captured contextual factors relevant to the guideline target setting and audience. RESULTS: The guideline development group considered and accounted for the complexities of opioid deprescribing at the individual and health system level, shaping recommendations and practice points to facilitate point-of-care use. Stakeholders exhibited diverse preferences, beliefs, and values. This variability, low certainty of evidence, and system-level policies and funding models impacted the strength of the generated recommendations, resulting in the formulation of four 'conditional' recommendations. CONCLUSION: The context within which evidence-based recommendations are considered, as well as the political and health system environment, can contribute to the success of recommendation implementation. Use of an EtD framework allowed for the development of implementable recommendations relevant at the point-of-care through consideration of limitations of the evidence and relevant contextual factors.

Screening for lipid nanoparticles that modulate the immune activity of helper T cells towards enhanced antitumour activity.

Lipid nanoparticles (LNPs) can be designed to potentiate cancer immunotherapy by promoting their uptake by antigen-presenting cells, stimulating the maturation of these cells and modulating the activity of adjuvants. Here we report an LNP-screening method for the optimization of the type of helper lipid and of lipid-component ratios to enhance the delivery of tumour-antigen-encoding mRNA to dendritic cells and their immune-activation profile towards enhanced antitumour activity. The method involves screening for LNPs that enhance the maturation of bone-marrow-derived dendritic cells and antigen presentation in vitro, followed by assessing immune activation and tumour-growth suppression in a mouse model of melanoma after subcutaneous or intramuscular delivery of the LNPs. We found that the most potent antitumour activity, especially when combined with immune checkpoint inhibitors, resulted from a coordinated attack by T cells and NK cells, triggered by LNPs that elicited strong immune activity in both type-1 and type-2 T helper cells. Our findings highlight the importance of optimizing the LNP composition of mRNA-based cancer vaccines to tailor antigen-specific immune-activation profiles.

Continued Opioid Use and Adverse Events Following Provision of Opioids for Musculoskeletal Pain in the Emergency Department: A Systematic Review and Meta-Analysis.

BACKGROUND: The prevalence of continued opioid use or serious adverse events (SAEs) following opioid therapy in the emergency department (ED) for musculoskeletal pain is unclear. The aim of this review was to examine the prevalence of continued opioid use and serious adverse events (SAEs) following the provision of opioids for musculoskeletal pain in the emergency department (ED) or at discharge. METHODS: Records were searched from MEDLINE, EMBASE and CINAHL from inception to 7 October 2022. We included randomised controlled trials and observational studies enrolling adult patients with musculoskeletal pain who were administered and/or prescribed opioids in the ED. Continued opioid use and opioid misuse data after day 4 since ED discharge were extracted. Adverse events were coded using the Common Terminology Criteria for Adverse Events (CTCAE), and those rated as grades 3-4 (severe or life-threatening) and grade 5 (death) were considered SAEs. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. RESULTS: Seventy-two studies were included. Among opioid-naïve patients who received an opioid prescription, 6.8-7.0% reported recent opioid use at 3-12 months after discharge, 4.4% filled ≥ 5 opioid prescriptions and 3.1% filled > 90-day supply of opioids within 6 months. The prevalence of SAEs was 0.02% [95% confidence interval (CI) 0, 0.2%] in the ED and 0.1% (95% CI 0, 1.5%) within 2 days. One study observed 42.9% of patients misused opioids within 30 days after discharge. CONCLUSIONS: Around 7% of opioid-naïve patients with musculoskeletal pain receiving opioid therapy continue opioid use at 3-12 months after ED discharge. SAEs following ED administration of an opioid were uncommon; however, studies only monitored patients for 2 days. PROTOCOL REGISTRATION: 10.31219/osf.io/w4z3u.

Opioid analgesia for acute low back pain and neck pain (the OPAL trial): a randomised placebo-controlled trial.

BACKGROUND: Opioid analgesics are commonly used for acute low back pain and neck pain, but supporting efficacy data are scarce. We aimed to investigate the efficacy and safety of a judicious short course of an opioid analgesic for acute low back pain and neck pain. METHODS: OPAL was a triple-blinded, placebo-controlled randomised trial that recruited adults (aged ≥18 years) presenting to one of 157 primary care or emergency department sites in Sydney, NSW, Australia, with 12 weeks or less of low back or neck pain (or both) of at least moderate pain severity. Participants were randomly assigned (1:1) using statistician-generated randomly permuted blocks to guideline-recommended care plus an opioid (oxycodone-naloxone, up to 20 mg oxycodone per day orally) or guideline-recommended care and an identical placebo, for up to 6 weeks. The primary outcome was pain severity at 6 weeks measured with the pain severity subscale of the Brief Pain Inventory (10-point scale), analysed in all eligible participants who provided at least one post-randomisation pain score, by use of a repeated measures linear mixed model. Safety was analysed in all randomly assigned eligible participants. The trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000775516). FINDINGS: Between Feb 29, 2016, and March 10, 2022, 347 participants were recruited (174 to the opioid group and 173 to the placebo group). 170 (49%) of 346 participants were female and 176 (51%) were male. 33 (19%) of 174 participants in the opioid group and 25 (15%) of 172 in the placebo group had discontinued from the trial by week 6, due to loss to follow-up and participant withdrawals. 151 participants in the opioid group and 159 in the placebo group were included in the primary analysis. Mean pain score at 6 weeks was 2·78 (SE 0·20) in the opioid group versus 2·25 (0·19) in the placebo group (adjusted mean difference 0·53, 95% CI -0·00 to 1·07, p=0·051). 61 (35%) of 174 participants in the opioid group reported at least one adverse event versus 51 (30%) of 172 in the placebo group (p=0·30), but more people in the opioid group reported opioid-related adverse events (eg, 13 [7·5%] of 174 participants in the opioid group reported constipation vs six [3·5%] of 173 in the placebo group). INTERPRETATION: Opioids should not be recommended for acute non-specific low back pain or neck pain given that we found no significant difference in pain severity compared with placebo. This finding calls for a change in the frequent use of opioids for these conditions. FUNDING: National Health and Medical Research Council, University of Sydney Faculty of Medicine and Health, and SafeWork SA.

Physiotherapists should apply health coaching techniques and incorporate accountability to foster adherence to a walking program for low back pain: a qualitative study.

QUESTIONS: What motivates individuals to start a walking program for the prevention of low back pain? What strategies optimise short-term and long-term adherence to a walking program? What strategies can physiotherapists incorporate into clinical practice to facilitate commencement of and adherence to a walking program? DESIGN: Qualitative study. PARTICIPANTS: Twenty-two adults recently recovered from an episode of non-specific low back pain who participated in a 6-month, progressive and individualised walking program that was prescribed by a physiotherapist trained in health coaching. METHODS: Semi-structured focus groups conducted online following completion of the walking program. Interview questions explored: primary motivations for starting a walking program, identification of which elements were useful in optimising adherence to the program, and identification of the barriers to and facilitators of engagement with the program. Audio recordings were transcribed and thematic analysis was conducted. RESULTS: Three major themes were identified. Theme one identified that strong motivators to start a walking program were anticipated improvements in low back pain management and the added general health benefits of a more active lifestyle. Theme two identified that fear of high-impact exercises led to avoidance; however, walking was considered a safe exercise option. Theme three identified accountability, enjoyment of exercise and health benefits were critical to adherence. CONCLUSION: Participants recently recovered from low back pain reflected positively on a physiotherapist-prescribed walking program. Participants described what elements of the program were crucial to starting exercise and optimising adherence. These findings have informed a list of practical recommendations for physiotherapists to improve patient commencement and adherence to exercise.

Identification of the pore-forming and binding domains of the Sneathia vaginalis cytopathogenic toxin A.

The association between Sneathia vaginalis and preterm birth is emerging. The Gram-negative anaerobe produces a large exotoxin, the cytopathogenic toxin A (CptA), that forms pores in human epithelial cells and red blood cells. The structure of the toxin has not been determined, but in silico analysis predicts that a large amino-terminal region of the protein is globular and separated from the carboxy-terminal tandem repeats by a disordered region. We found that a recombinant protein consisting of the predicted structured amino-terminal portion of CptA and devoid of the repeat region was sufficient to permeabilize epithelial cells and red blood cells. The repeat region was capable of binding to epithelial cells but did not permeabilize them or lyse red blood cells. CptA is the only S. vaginalis virulence factor that has been examined mechanistically to date, and this analysis sets the foundation for an understanding of how this novel pore-forming toxin exerts its activity.

Recommendations for terminology and the identification of neuropathic pain in people with spine-related leg pain. Outcomes from the NeuPSIG working group.

ABSTRACT: Pain radiating from the spine into the leg is commonly referred to as "sciatica," "Sciatica" may include various conditions such as radicular pain or painful radiculopathy. It may be associated with significant consequences for the person living with the condition, imposing a reduced quality of life and substantial direct and indirect costs. The main challenges associated with a diagnosis of "sciatica" include those related to the inconsistent use of terminology for the diagnostic labels and the identification of neuropathic pain. These challenges hinder collective clinical and scientific understanding regarding these conditions. In this position paper, we describe the outcome of a working group commissioned by the Neuropathic Pain Special Interest Group (NeuPSIG) of the International Association for the Study of Pain (IASP) which was tasked with the following objectives: (1) to revise the use of terminology for classifying spine-related leg pain and (2) to propose a way forward on the identification of neuropathic pain in the context of spine-related leg pain. The panel recommended discouraging the term "sciatica" for use in clinical practice and research without further specification of what it entails. The term "spine-related leg pain" is proposed as an umbrella term to include the case definitions of somatic referred pain and radicular pain with and without radiculopathy. The panel proposed an adaptation of the neuropathic pain grading system in the context of spine-related leg pain to facilitate the identification of neuropathic pain and initiation of specific management in this patient population.