Topical anti-inflammatory medication may help deep spinal pain
Two articles on PainSci cite Huang 2011: 1. The Complete Guide to Low Back Pain 2. Voltaren Gel: Does It Work?
PainSci commentary on Huang 2011: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
It may seem surprising, but these scientists found evidence that an anti-inflammatory cream on the skin (such as Voltaren) might be able to treat pain coming from deep inside the spine — right in the centre — which means it could be a “convenient and safe clinical intervention” for a few types of back pain. So convenient and safe, in fact, that it lands in the clinical “why not?” sweet spot. An anti-inflammatory gel will probably fail with many kinds of back pain, but there’s also virtually no down-side.
Fascinatingly, these results also demonstrate the importance of some principles of pain science, namely that interactions with the skin can be surprisingly profound for the body. And from that one can also say some nice, reasonable things about why massage therapy might be effective.
There’s really quite a lot of scientific innuendo packed into this little study.
~ Paul Ingraham
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
There is lack of evidence that topical application of an anti-inflammatory reagent could reduce pain due to intervertebral foramen (IVF) inflammation (IVFI). We investigated analgesic effects and underlying mechanisms of topical application of a compound ibuprofen cream (CIC) onto the surface of back skin covering the inflamed L(5) IVF in a rat model. Repetitive CIC treatment (∼.54 g each treatment daily for 5 consecutive days) significantly reduces severity and duration of IVFI-induced thermal hyperalgesia and mechanical allodynia by 80 to 100\% and 50 to 66\%, respectively. Electrophysiological studies and Western blot analysis demonstrated that CIC treatment significantly inhibited hyperexcitability of the inflamed dorsal root ganglion (DRG) neurons and upregulation of Nav1.7 and Nav1.8 protein, respectively. Pathological manifestations of the inflamed DRG were also markedly improved following CIC treatment. Further, in the inflamed DRGs, phosphorylation and expression of transcription factor NF-κB and pro-inflammatory enzyme cyclooxygenase-2 (COX-2) were significantly increased, while a cytokine IL-1β level was increased. IVFI-induced upregulation of these molecules was significantly inhibited by CIC treatment. This study provides evidence that an anti-inflammatory reagent can be used topically to suppress pain due to IVFI and/or DRG inflammation through inhibition of sensory neuron hyperexcitability and the immune and inflammatory responses.
PERSPECTIVE: This study suggests a convenient and safe clinical intervention for treating pain due to intervertebral foramen inflammation and similar syndromes.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Inciting events associated with lumbar disc herniation. Suri 2010 Spine J.
- Prediction of an extruded fragment in lumbar disc patients from clinical presentations. Pople 1994 Spine (Phila Pa 1976).
- Characteristics of patients with low back and leg pain seeking treatment in primary care: baseline results from the ATLAS cohort study. Konstantinou 2015 BMC Musculoskelet Disord.
- Effectiveness and cost-effectiveness of universal school-based mindfulness training compared with normal school provision in reducing risk of mental health problems and promoting well-being in adolescence: the MYRIAD cluster randomised controlled trial. Kuyken 2022 Evid Based Ment Health.
- No long-term effects after a three-week open-label placebo treatment for chronic low back pain: a three-year follow-up of a randomized controlled trial. Kleine-Borgmann 2022 Pain.