March 21, 2024
Annals of Emergency Medicine
TAKE-HOME MESSAGE
- This randomized placebo-controlled trial evaluated the use of diclofenac gel versus oral ibuprofen for acute low back pain in the emergency department and found that topical diclofenac gel was significantly less effective in relieving pain and improving function 2 days after prescription compared with oral ibuprofen 400 mg. Furthermore, a combination of oral ibuprofen and diclofenac gel showed no additional benefit compared with ibuprofen alone.
- This study suggests that topical diclofenac is likely inferior to oral ibuprofen for acute low back pain, and the combination of the two has no additional benefit.
Abstract
STUDY OBJECTIVE
Topical nonsteroidal anti-inflammatory drugs (NSAIDs) are useful for a variety of musculoskeletal injuries. It is not known whether topical NSAIDs should be used for patients presenting with acute nonradicular musculoskeletal low back pain.
METHODS
We conducted a randomized, placebo-controlled double-blind study in which patients 18 to 69 years of age visiting the emergency department (ED) with acute, nontraumatic, nonradicular, musculoskeletal low back pain were randomized at the time of discharge to treatment with 400 mg oral ibuprofen + placebo topical gel, 1% diclofenac topical gel + oral placebo, or 400 mg ibuprofen + 1% diclofenac topical gel. We measured outcomes using the Roland Morris Disability Questionnaire (RMDQ), a 24-item yes/no instrument about the effect of back pain on a respondent’s daily activities. The primary outcome was change in RMDQ score between ED discharge and 2 days later. Medication-related adverse events were elicited by asking whether the study medications caused any new symptoms.
RESULTS
In total, 3,281 patients were screened for participation, and 198 were randomized. Overall, 36% of the population were women, the mean age was 40 years (standard deviation, 13), and the median RMDQ score at baseline was 18 (25th to 75th percentile: 13 to 22), indicating substantial low back-related functional impairment. In total, 183 (92%) participants provided primary outcome data. Two days after the ED visit, the ibuprofen + placebo group had improved by 10.1 (95% confidence interval [CI] 7.5 to 12.7), the diclofenac gel + placebo group by 6.4 (95% CI 4.0 to 8.8), and the ibuprofen + diclofenac gel by 8.7 (95% CI 6.3 to 11.1). The between-group differences were as follows: ibuprofen versus diclofenac, 3.7 (95% CI 0.2 to 7.2); ibuprofen versus both medications 1.4 (95% CI -2.1 to 4.9); and diclofenac versus both medications, 2.3 (95% CI -5.7 to 1.0). Medication-related adverse events were reported by 3/60 (5%) ibuprofen patients, 1/63 (2%) diclofenac patients, and 4/64 (6%) patients who received both.
CONCLUSION
Among patients with nontraumatic, nonradicular acute musculoskeletal low back pain discharged from an ED, topical diclofenac was probably less efficacious than oral ibuprofen. It demonstrated no additive benefit when coadministered with oral ibuprofen.
Oral versus topical NSAIDs for acute low back pain
Clinical question
Does topical diclofenac alone or combined with oral ibuprofen offer superior pain and functionality outcomes for patients with acute low back pain who present at the emergency department, compared with oral ibuprofen alone?
Key points
Relevance
Recently, evidence has pointed to the benefit of topical NSAIDs in the management of osteoarthritis.1 There is currently little evidence on whether topical NSAIDs provide similar benefits in the setting of acute low back pain, which is a common reason for presentation at the emergency department. Although this condition is often self-limiting, it is sometimes associated with ongoing use of oral NSAIDs, which can be associated with multisystem adverse events.
Details
Trial design: randomized, placebo-controlled, double-blind study
Setting: two emergency departments with a combined annual visit volume of 175,000, affiliated with Montefiore Medical Center
Patients: a total of 198 participants aged between 18 and 69 years visiting the emergency department with acute, nontraumatic, non-radicular, musculoskeletal low back pain with no diagnosis of other chronic pain issues
Treatments: participants were randomized at the time of discharge to treatment with either of the regimens below
Endpoints
The primary outcome was a change in disability assessed using the Roland Morris Disability Questionnaire between discharge and 2 days later.
Secondary outcomes included disability at 7 days, and medication-related adverse events were also elicited.
Limitations
Outcomes at 7 days were comparable with oral versus topical NSAIDs; however, only 2 days of medications were provided, so this may be more related to the natural history of the condition.
Clinical bottom line
For patients with acute nontraumatic nonradicular low back pain, oral ibuprofen is more effective than topical diclofenac but is associated with a higher risk of acute adverse events. The combination of both does not appear to have an advantage.
Importantly, topical NSAIDs continue to be a safer and more effective choice for chronic joint pain with a reduction in gastrointestinal adverse events by about 25%. This is a helpful summary of five things to know about topical NSAIDs — to help in discussing with patients — from the study by Bhat et al published in the Canadian Medical Association Journal .2
Remaining questions
Although this is an important study to guide emergency department treatment of this common condition, questions remain regarding the potential of topical NSAIDS to help individuals with ongoing pain, which may require chronic NSAID therapy. Knowing that topical medications have a slower onset of action and require prolonged use, it would be interesting to repeat this study with ongoing use of the three arms to help discover when topical medication only may catch up with oral and potentially allow a switch in therapy to more safely managing ongoing pain with NSAIDs alone.
References