Date: October 26, 2023
Reference: Jones et al. Opioid analgesia for acute low back pain and neck pain (the OPAL trial): a randomised placebo-controlled trial placebo-controlled trial. Lancet July 2023
Guest Skeptic: Dr. Sergey Motov is an Emergency Physician in the Department of Emergency Medicine, Maimonides Medical Center in New York City. He is also one of the world’s leading researchers on pain management in the emergency department, specifically the use of ketamine. His twitter handle is @PainFreeED.
Case: A 37-year-old man without a significant past medical history presents to the emergency department (ED) with a chief complaint of lower back pain that started three days prior to the ED visit after unloading a truck with furniture. He states that pain is severe (7/10 in intensity), sharp, constant, non-radiating, and is exacerbated by any movement. The patient is unable to go to work due to pain and is experiencing severe limitations in his daily activities. He denies any weakness or numbness of the lower extremities or bowel or bladder dysfunction. You perform a physical examination and note prominent tenderness to palpation at bilateral lumbar paraspinal regions with normal neuro-vascular examination. You engage the patient in shared decision making about his most likely diagnosis (muscle strain) and treatment approach such as a short course of non-steroidal anti-inflammatory drugs (Ibuprofen) and gradual physical activity as tolerated. The patient, however, believes that ibuprofen will not touch his pain and insists on receiving an opioid-containing medication.
Background: Low back pain and neck pain are extremely common conditions worldwide [1]. We have covered the issue of back pain several times on the SGEM including:
SGEM#87:Let Your Back Bone Slide (Paracetamol for Low-Back Pain)
SGEM#173: Diazepam Won’t Get Back Pain Down
SGEM#240: I Can’t Get No Satisfaction for My Chronic Non-Cancer Pain
SGEM#304: Treating Acute Low Back Pain – It’s Tricky, Tricky, Tricky
SGEM#366: Relax, Don’t Do It – Skeletal Muscle Relaxants for Low Back Pain
Back pain and neck pain are leading causes of disability on a global scale [2,3]. The substantial disability burden imposes enormous costs both directly on healthcare systems, and indirectly through productivity losses [4,5].
Not only are these conditions common and painful they are difficult to treat. Many pharmacologic treatments have been tried with limited efficacy.
Acetaminophen (Williams et al Lancet 2014)
Muscle relaxants (Friedman et al JAMA 2015)
NSAIDs (Machado et al Ann Rheum Dis 2017)
Steroids (Balakrishnamoorthy et al Emerg Med J 2014)
Benzodiazepines (Friedman et al Ann Emerg Med 2017)
Many non-pharmacologic therapies have also been tried with limited efficacy.
Cognitive Behavioral Therapy and mindfulness (Cherkin et al JAMA 2016)
Chiropractic (Paige et al JAMA 2017)
Physical therapy (Paolucci et al J Pain Research 2018)
Acupuncture (Colquhoun and Novella Anesthesia and Analgesia 2013)
One treatment modality, opioids, can be effective but comes with very real potential harms. The American College Physicians (ACP) has a 2017 policy on guidelines for treating non-radicular low back pain (Qaseem et al Annals of Int Med). Their third recommendations states:
Clinicians should only consider opioids as an option in patients who have failed the aforementioned treatments and only if the potential benefits outweigh the risks for individual patients and after a discussion of known risks and realistic benefits with patients. (Grade: weak recommendation, moderate-quality evidence)
The American College of Emergency Physicians (ACEP) has addressed the issue of opioid use in patients being discharged home after an acute episode of pain. They give a Level C Recommendations saying:
Do not routinely prescribe, or knowingly cause to be co-prescribed, a simultaneous course of opioids and benzodiazepines (as well as other muscle relaxants/sedative-hypnotics) for treatment of an acute episode of pain in patients discharged from the emergency department (Consensus recommendation).
Despite guidelines and policy recommendations for prudent short-term opioid use only after other analgesics fail [6], opioid medications are frequently prescribed as the initial treatment for patients presenting with acute low back pain or neck pain. Estimates suggest up to two-thirds of these patients in Australia may receive opioids first-line [7].
Opioid prescription rates remain high in many countries including the USA. One study reported 43 prescriptions dispensed per 100 people in the US in 2020, though efforts have been made recently to curtail this use [8]. The prevalent use of opioids for acute back and neck pain is concerning given the lack of direct, high-quality evidence supporting efficacy [9].
Clinical Question: Is a short course of an opioid analgesic effective at reducing pain severity and improving function and quality of life in patients with acute non-specific low back pain or neck pain compared to placebo?
Reference: Jones et al. Opioid analgesia for acute low back pain and neck pain (the OPAL trial): a randomised placebo-controlled trial placebo-controlled trial. Lancet July 2023
Population: Adults aged 18 years or older with acute low back pain, neck pain, or both with or without radiation to the leg or arm of at least moderate severity that has been lasting for 12 weeks or less and preceded by at least a 1-month period free from back and neck pain. Participants were recruited via emergency department, primary care offices or through a social media campaign.
Exclusions: Known or suspected serious spinal pathology; contraindications to opioid analgesics; taken a prescription opioid analgesic for the current episode of low back pain or neck pain at a dose higher than 15 mg of oral morphine equivalent per day for 5 or more consecutive days; spinal surgery in the preceding 6 months; scheduled or being considered for surgery or interventional procedures for low back pain or neck pain (or both) during the 6-week treatment period; younger than 18 years; insufficient English language skills or if interpretation was unavailable; and female participants who were planning conception, pregnant, or breastfeeding.
Intervention: Oxycodone-naloxone modified release tablets (5mg oxycodone/2.5mg naloxone) given orally for up to 6 weeks twice daily with allowable titration up to a maximum of 10mg oxycodone/5mg naloxone twice daily based on pain severity, tolerability, and sedation scores. Down-titration and cessation occurred once adequate pain improvement was achieved (pain score 0-1 out of 10 for 3 consecutive days or for a maximum of 6 weeks)
Comparison: Identical-appearing placebo tablets containing inactive ingredients that followed the same dosing regimen and schedule as the intervention group. Both groups also received guideline-recommended care for acute spinal pain in addition to the study medication/placebo.
Outcome:
Primary Outcome: Pain intensity measured on a 0–10 scale by the Brief Pain Inventory Pain Severity Subscale at 6 weeks after randomization.
Secondary Outcomes:
Global Perceived Effect Scale: Assessed at weeks 2, 4, 6, and 12.
Physical Functioning (Generic): Measured by the Brief Pain Inventory Interference Subscale (BPI-IS) at weeks 2, 4, 6, and 12.
Physical Functioning (Back): Measured by the Roland Morris Disability Questionnaire (RMDQ) at week 6.
Physical Functioning (Neck): Measured by the Neck Disability Index (NDI) as a percentage at week 6.
Quality of Life (Physical Score): Measured by the SF-12v2 at weeks 2, 4, 6, and 12.
Quality of Life (Mental Score): Measured by the SF-12v2 at weeks 2, 4, 6, and 12.
Pain severity at other timepoints (2, 4, 12, 26, 52 weeks)
Time to recovery
Healthcare utilization
Work absenteeism
Adverse events
Risk of opioid misuse (Current Opioid Misuse Measure scale)
Type of Study: A randomized, triple-blinded, placebo-controlled trial with parallel groups and intention-to-treat analysis.
Authors’ Conclusions: “Opioids should not be recommended for acute non-specific low back pain or neck pain given that they 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.”
Quality Checklist for Randomized Clinical Trials:
The study population included or focused on those in the emergency department. No
The patients were adequately randomized. Yes
The randomization process was concealed. Yes
The patients were analyzed in the groups to which they were randomized. Yes
The study patients were recruited consecutively (i.e. no selection bias). Unsure
The patients in both groups were similar with respect to prognostic factors. Yes
All participants (patients, clinicians, outcome assessors) were unaware of group allocation. Unsure
All groups were treated equally except for the intervention. Yes
Follow-up was complete (i.e. at least 80% for both groups). No
All patient-important outcomes were considered. Yes
The treatment effect was large enough and precise enough to be clinically significant. No
Financial conflicts of interest. The authors stated that the funders of the study had no role in the study design, data collection, analysis, interpretation, or reporting. The sources of funding included government agencies and academic institutions. No industry funding was reported. All authors declared no competing interests related to the submitted work. Two authors received research fellowships from the National Health and Medical Research Council of Australia. No other financial relationships or conflicts of interest were reported.
Results: 347 participants were recruited to be randomized.