What is the evidence for oral and transdermal opioids in the treatment of osteoarthritis of the knee?
AMSTAR Rating
Summary
Patient Population:
Patients studied were diagnosed with either hip or knee OA.
Intervention:
Transdermal fentanyl was studied in 1 trial. The remainder of trials examined the use of various oral opioids (morphine = 1, oxycodone=4, oxymorphone=4).
Comparison:
10 trials were selected for inclusion in the review. All trials were described as double-blind studies. However, poor reporting quality was noted as responsible for inability to ascertain whether concealed allocation had been adequately carried out in most cases. 7/10 trials reported using ITT analysis, but the review authors did not consider this to have been the case for the primary outcome of pain and function. In terms of adverse events, the quality of evidence was considered to be moderate to low due to the low number of trials reporting outcomes, and low numbers of events reported.
Outcome:
- Pain: fentanyl patch vs. placebo (1 study) – significant difference in favour of the patch (SMD = -0.22; 95% CI, -0.42 to -0.03).
- Pain: opioids vs. placebo (10 studies) – significant difference in favour of opioids (SMD = -0.36; 95% CI -0.47 to -0.26; NNT = 8).
- Function: fentanyl patch vs. placebo (1 study) – significant difference in favour of the patch (SMD=-0.28; 95% CI -0.48 to -0.09).
- Function: opioids vs. placebo (10 studies) – significant difference in favour of opioids (SMD=-0.33; 95% CI -0.45 to -0.21).A
- Safety: There was a significant increase in risk for adverse events associated with allocation to the fentanyl patch group (RR=1.55; 95% CI 1.33 to 1.81).
- Safety: There was a significant increase in risk for adverse events associated with allocation to an opioid treatment condition (RR=1.55; 95% CI 1.41 to 1.7; NNH= 12).
Guideline Recommendations
| Source | Recommendation |
|---|---|
| ACR (2019) Tramadol | Conditionally recommended |
| ACR (2019) Non-tramadol Opioids | Conditionally against |
| AAOS (2013) Tramadol | Strong evidence for use |
| AAOS (2013) Non-tramadol Opioids | Inconclusive |
Outcomes Assessed
- Benefit
- Harm
- Inconclusive
Fentanyl Patch
Pain
Function
Safety
Oral Opioids
Pain
Function
Safety
