UMEM Educational Pearls

A recent study in Annals of EM investigated the use of topical Diclofenac in the treatment of lower back pain.

Small studies have shown topical NSAIDs to be effective for single joint OA and tendinopathies.

Currently, NSAIDs are first-line treatment for ED patients with acute low back pain.

Theoretically, topical NSAIDs deliver medications directly to the injured tissue while minimizing systemic side effects.

-Topical NSAIDs provide similar concentrations of the drugs in muscle tissue but much lower plasma concentrations than oral formulations

Design: Randomized, double-blind, placebo-controlled trial.

ED patients aged 18 to 69 years with non-radicular, non-traumatic acute lower back pain.

Screened 3,281 and enrolled 198.

Study groups:

  1. Ibuprofen arm (400 mg oral ibuprofen plus placebo gel every 6 hours as needed)
  2. Diclofenac arm (1% diclofenac gel, 4 g topically, plus placebo capsules every 6 hours as needed)
  3. Combination arm (400 mg oral ibuprofen plus 1% gel diclofenac, 4 g topically, every 6 hours as needed)

Patients received 2 days of meds. Follow up by phone at 2 and 7 days.

Investigators used the RMDQ score to measures pain and functional impairment.

Results: At the 2 day follow-up, all 3 groups showed an improvement in the mean RMDQ score compared to baseline as expected.

Participants had a mean RMDQ improvement of 10.1 in the ibuprofen group, 6.4 in the diclofenac gel group, and 8.7 in the ibuprofen + diclofenac gel group.

At the 7-day follow-up, participants had a mean RMDQ change compared to baseline of 12.2 in the ibuprofen group, 9.5 in the diclofenac group, and 10.7 in the ibuprofen + diclofenac gel group.

Conclusion: This study does not support the use of topical diclofenac among patients who can otherwise tolerate oral ibuprofen.

Because the study did not compare placebo gel to topical Diclofenac, we cannot infer whether topical medication is helpful for treatment in acute lower back pain in those patients who may not be able to take NSAIDs.


Khankhel N, et al. Topical Diclofenac Versus Oral Ibuprofen Versus Diclofenac + Ibuprofen for Emergency Department Patients With Acute Low Back Pain: A Randomized Study. Ann Emerg Med. 2024 Jun;83(6):542-551.