Efficacy of topical non-steroidal anti-inflammatory drugs in the treatment of osteoarthritis: meta-analysis of randomised controlled trials.
OBJECTIVE
To assess the efficacy of topical non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of osteoarthritis.


METHODS
Medline, Embase, Scientific Citation Index, CINAHL, Cochrane Library, and abstracts from conferences.


METHODS
Inclusion criterion was randomised controlled trials comparing topical NSAIDs with placebo or oral NSAIDs in osteoarthritis. Effect size was calculated for pain, function, and stiffness. Rate ratio was calculated for dichotomous data such as clinical response rate and adverse event rate. Number needed to treat to obtain the clinical response was estimated. Quality of trial was assessed, and sensitivity analyses were undertaken.


RESULTS
Topical NSAIDs were superior to placebo in relieving pain due to osteoarthritis only in the first two weeks of treatment. Effect sizes for weeks 1 and 2 were 0.41 (95% confidence interval, 0.16 to 0.66) and 0.40 (0.15 to 0.65), respectively. No benefit was observed over placebo in weeks 3 and 4. A similar pattern was observed for function, stiffness, and clinical response rate ratio and number needed to treat. Topical NSAIDs were inferior to oral NSAIDs in the first week of treatment and associated with more local side effects such as rash, itch, or burning (rate ratio 5.29, 1.14 to 24.51).


CONCLUSIONS
Randomised controlled trials of short duration only (less than four weeks) have assessed the efficacy of topical NSAIDs in osteoarthritis. After two weeks there was no evidence of efficacy superior to placebo. No trial data support the long term use of topical NSAIDs in osteoarthritis.
Lin
Jinying
J
Academic Rheumatology, University of Nottingham, City Hospital, Nottingham NG5 1PB.
Zhang
Weiya
W
Jones
Adrian
A
Doherty
Michael
M
D000287:Administration, Topical; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D010003:Osteoarthritis / Q000188:drug therapy*; D010146:Pain / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome
D000894:Anti-Inflammatory Agents, Non-Steroidal