Steroid injections beneficial for knee OA

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Rheumawire

Apr 7, 2004

Steroid injections beneficial for knee OA

Auckland, New Zealand - The first meta-analysis of corticosteroid

injections for osteoarthritis (OA) of the knee shows that this is a

beneficial intervention and is probably effective in improving symptoms

for 16 to 24 weeks.

Although the actual dose of steroid required to improve symptoms is not

clear from this review, there is some evidence that higher doses are

better, say Drs Bruce Arroll and Felicity Goodyear- (Health

University of Auckland, New Zealand) in their BMJ paper, published

online March 23, 2004 [1].

Arroll told rheumawire that he is recommending steroid injections to his

patients. " It may save them from having surgery or at least delay it, "

he notes.

The researchers explain that intra-articular injection of a steroid is a

common treatment for OA of the knee, with clinical evidence suggesting

that any benefit is short-lived, usually 1 to 4 weeks. Concern has been

expressed that long-term treatment could promote joint destruction and

tissue atrophy, they note, although they add that studies of cartilage

damage tend to suggest that these changes are more likely due to the

underlying disease than to the steroid injection.

Hence, they decided to conduct their meta-analysis, with the smallest

study including 12 patients and the largest 71. They note that the size

of the studies is a possible limitation of the analysis. Only 6 studies

provided data at 2 weeks on improvement of symptoms of OA of the knee

after intra-articular corticosteroid injection, and these showed a

significant improvementrelative risk 1.66and the number needed to treat

for 1 improvement was 1.3 to 3.5 patients.

Of the 10 studies, 3 provided data at 16 to 24 weeks, and 2 of these

were determined to be of high quality (because of randomization and

blinding). For these 2 studies, the pooled relative risk for improvement

in symptoms at 16 to 24 weeks was 2.09, and the number needed to treat

was 4.4. Neither of these 2 studies was significant, however, although

Arroll told rheumawire, " They were probably too small to detect a true

difference. " Also, significant heterogeneity was found when the 1

low-quality study was included in the analysis, they note. They also

analyzed 2 high-dose studies separately.

" This is the first meta-analysis on this topic and the first review to

show benefits of such injections in improvement of symptoms, which may

extend beyond 16 weeks, " they state.

But the researchers note, " The dose of corticosteroid required to

improve symptoms is not clear from our review. The equivalent dose of

prednisone varied from 6.25 mg to 80 mg. A dose of 20 mg of

triamcinolone (equivalent to 25 mg of prednisone) seems to be

efficacious for pain control at 2 weeks. Only 1 study used 40 mg of

triamcinolone, and this found a benefit at 24 months for night pain and

stiffness on 1 scale but not on another. "

They add, " The 3 studies that reported improvement at 16 weeks used

different cortisones. The 2 studies using high doses showed a

statistically significant benefit, suggesting that higher-dose steroids

may give a longer benefit. "

Arroll told rheumawire: " My advice to rheumatologistsand I have started

doing this with my own patientsis to say that there is evidence that up

to 120 mg of triamcinolone (which is 3 to 6 times the currently used

doses) may give patients longer relief from their knee pain. "

However, he stressed, " What is not known is the safety of this. There is

evidence that 40 mg every 3 months for 2 years is safe, so they may be

taking a small risk that larger doses could be harmful. This puts the

ball in the patients' court. So far they have been keen to try this,

with some good results. "

Nainggolan

Source

1. Arroll B, Goodyear- F. Corticosteroid injections for

osteoarthritis of the knee: meta-analysis. BMJ

[DDOI:10.1136/bmj.38039.573970.7C]. 2004 Mar 23. Available at:

http://www.bmj.com.

I'll tell you where to go!

Mayo Clinic in Rochester

http://www.mayoclinic.org/rochester

s Hopkins Medicine

http://www.hopkinsmedicine.org