To pain trainees - from my reading and understanding it remains unclear whether quoting references is helpful in the exam. It is a very foreign thing to a GP - but apparently very common in anaesthetic examinations.
However, either way having some up-to-date resources to talk about (if you can remember them) could be helpful for written, viva/osce's and long case.
So here is MY take on the key articles to quote for the following conditions and management steps. These are my own notes and my own take - so please review these yourself and decide if they are suitable for you and your study needs. It is definitely not exhaustive - and if you have a better article, or more up to date, please let me know.
Conditions:
Low back pain
1. Lancet Back Pain Series - Foster et al. 2018 - Review article
- I feel this series has everything you need to be able to quote for low back pain. From allied health and lifestyle management, to pharmacological management, and to procedural/surgical options. I suggest quoting this reference if you are discussing any of these topics particularly.
CRPS
1. Complex Regional Pain Syndrome: A Comprehensive Review - Taylor et al 2021 - Pain Therapeutics - Review article
TLDR:
- NSAIDs - No (RCTs)
- Steroids - Short term benefit under 3 mths - mainly in function (RCTs)
- Bisphosphonates - Reduced pain, swelling and improved function (RCTs)
- Gabapentin - Evidence of benefit but very small RCTs
- Ketamine - Low quality evidence but suggestion of benefit
- Vitamin C (this one says benefit - but I have read elsewhere less likely benefit than previously thought)
- Naltrexone, Botox, IVIG, Plasmapheresis - too small data
- Medicinal cannabis - conflicting results - no evidence of benefit
- Sympathetic blocks - This says clinically significant benefit (other studies say otherwise)
- Transcranial magnetic stimulation - Unknown yet
- SCS - Thought to be beneficial as a trial in patients failing conservative therapy at 12-16 weeks
- PNS - Maybe - quite unclear
- DRG - Maybe
- Amputation - Risks of PSP and PLP but some studies suggesting benefit
2. Treatment of complex regional pain syndrome: an updated systematic review and narrative synthesis - Duong et al. 2018 - Canadian Journal of Anaesthesia -Systematic review
- Duong et al. has a nice summation of current evidence for CRPS treatments. Similar to above with some differences. Particularly around sympathetics being less helpful.
Central pain syndromes
1. Central Neuropathic Pain Syndromes - Watson and Sandroni 2016 - Mayo Clinic Proceedings - Review article
- This article gives a good summation of evidence (or lack thereof) for central pain syndromes (e.g. post stroke, spinal cord injury etc). I haven't found a more up-to-date article instead and limited new studies that I am aware of. Essentially it states that the majority of evidence is extrapolated from other conditions/
Phantom limb pain
1. Clinical updates on phantom limb pain - Erlenwein et al. 2021 - Pain reports - Review article
- Good summary review on the evidence for phantom limb pain management. In summary, most of it is extrapolated from studies in other areas. + GMI/Mirror.
Fibromyalgia
1. EULAR revised recommendations for the management of fibromyalgia - Macfarlane et al. 2017 - Guidelines update
- Essential the European League Against Rheumatic diseases puts out a very thorough set of guidelines and summary of evidence for different conditions. The fibromyalgia one is quite good and worth a read. Also useful to quote.
Neuropathic pain
1. Pharmacotherapy for neuropathic pain in adults: a systematic review and meta-analysis - Finnerup et al. 2015 - Lancet Neurology - Meta analysis
2. Pharmacological treatments of neuropathic pain: The latest recommendations - Attal 2018 - Review Neurology (French) - Review article update to Finnerup et al.
- Note not much changed in 2018. Useful to be able to quote the NNTs for various medications for neuropathic pain I would suggest
TLDR - NNT is for 50% reduction in pain!
- TCA 3.6
- Gabapentin 6.3
- SNRI 6.4
- Pregabalin 7.7
Peripheral neuropathy
1. Pharmacological Management of Painful Peripheral Neuropathies: A Systematic Review - Liampas 2020 - Pain Therapies
- Useful information regarding peripheral neuropathies.
TLDR - There is evidence for diabetic neuropathy (e.g. duloxetine / TCA) but not much for other types of peripheral neuropathy
Procedures and interventions to quote
Chronic pain psychology: All pain conditions (except headaches)
Cochrane review 2021
- Large amount of studies concluding that CBT has small or very small effects for reducing pain, disability, and distress in chronic pain. Moderate level of evidence. Even less evidence either for or against behavioural therapy or acceptance and commitment therapy.
Chronic pain physiotherapy:
CRPS - Cochrane 2022
- The evidence is very uncertain about the effects of physiotherapy interventions on pain and disability in CRPS
Low back pain - Cochrane 2021
- Moderate evidence that exercise is probably effective vs placebo for chronic low back pain. Possible very small positive effects on pain, functional outcomes. Not shown in research to be better than manual therapy treatments.
Spinal Surgery:
SPORT trial - Systematic review (Brittany et al. 2020) - 10 year mark for review of outcomes - SPINE 2020
Summary: Spinal patient outcomes research trial (SPORT) - Initially a 5 year study that looked at intervertebral disc herniation, spinal stenosis, and degenerative spondylolisthesis..
- Surgical interventions showed greater benefit in pain and physical function scales from 6 weeks to 4 years. However from 4-8 years, differences in the groups has diminished.
HOWEVER - There are big question marks over the SPORT trial where they had a large amount of patients cross-over from non-surgery to surgery. Essentially they could choose to do so. So made the groups very muddy and interpretation more difficult. Confounders for why people may have changed groups was also not taken into account.
Spinal interventions:
RFA - MINT trial JAMA 2018 - https://pubmed.ncbi.nlm.nih.gov/28672319/
(Challenge by Cohen et al. 2020 - https://pubmed.ncbi.nlm.nih.gov/31831630/)
Non-blinded Randomised control trial looking at either facet joint blocks, sacroiliac joint blocks, or a combination of these, were selected who were also unresponsive to conservative care. All had a 3 mth exercise and psychology program.
Outcome was pain score at 3 months that was more than a score reduction by two. This was found to not be the case (negative trial).
It was heavily criticised however by Cohen et al. 2020 in Regional Anaesthesia and Pain Medicine which suggested:
Lack of experienced clinicians performing the procedure
Lack of appropriate follow up
RFA - Lee et al. 2022 Journal of pain research - https://pubmed.ncbi.nlm.nih.gov/34526815/
Opioids for chronic non-cancer pain:
SPACE trial - (Strategies for prescribing analgesics comparison effectiveness) - JAMA - Krebs et al. 2018 https://jamanetwork.com/journals/jama/fullarticle/2673971
TLDR: Essentially no benefit for opioids at 12 months over patients not given opioids for back pain, hip pain, or knee pain in OA. Function was the same. Interestingly overall pain scores were LOWER in those in the non-opioid group.
Cannabinoids:
FPM Statement: 2021 - Do not use Cannabinoid products outside of clinical trials. Current evidence is too heterogeneous and does not show benefit and the harms still remain somewhat unknown.
IASP 2021: Full review of literature does NOT endorse the use of cannabinoids to treat pain
IV Ketamine:
FPM Statement 2022: There is significant uncertainty regarding the literature and many different ways in which ketamine is prescribed/dosed. They recommend patients are fully informed that the use is off-label and patients are fully informed of the risks.
Cohen et al. 2018- Regional Anaesthesia and Pain Med - is the most referenced article by FPM - Consensus guidelines from ASRA, AAPM, and ASA. https://pubmed.ncbi.nlm.nih.gov/29870458/
IV Lignocaine:
Zhu et al. 2019 - Neuropharmacology - A systematic review essentially saying there is not clear evidence of benefit outside of short term gains.
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