Did Anonymous do more harm than good

More harm than good?

BOSTON. Injection therapy with intra-articular corticosteroids is a widely used treatment for symptomatic osteoarthritis of the knee. On the one hand, this seems plausible: there is evidence that the progression of osteoarthritis of the knee with progressive destruction of the intra-articular cartilage is based on inflammatory processes. Conversely, steroid therapy should be able to stop the loss of cartilage through its anti-inflammatory effect.

However, a study that was supposed to prove this hypothesis has now shown the opposite: As the researchers working with Timothy E. McAlindon from Tufts Medical Center in Boston report, osteoarthritis patients who had been regularly treated with triamcinolone injections in the knee for two years had , no advantage over a corresponding injection therapy with saline solution (JAMA 2017; 317: 1967–1975). For the experts, the benefit of intra-articular steroid therapy for osteoarthritis of the knee must therefore be fundamentally questioned.

Study with 140 osteoarthritis patients

The study included 140 patients with radiologically proven Kellgren-Lawrence grade 2 or 3 knee osteoarthritis. The mean age of the patients was 58 years and had knee pain that was at least 2 (at most 8) on the WOMAC scale. The value 0 on this scale stands for "no pain", 20 corresponds to "extreme pain".

The collective was divided into two groups of equal size: One received a 1 ml injection every three months with 40 mg / ml triamcinolone as the active ingredient, the others 1 ml 0.9% sodium chloride at equal intervals. Local anesthetics were not used.

59 patients from the triamcinolone group and 60 from the saline group completed all the planned visits in the two academic years, a total of nine. Above all, knee pain was recorded using the WOMAC score. A difference of at least 3.94 points was considered a clinically relevant improvement.

In order to record the cartilage loss, knee MRIs were performed at baseline and after 12 and 24 months. According to McAlindon and colleagues, the cartilage loss in the respective index compartment was significantly more pronounced in the triamcinolone group than in the comparison group. The cartilage thickness had decreased by 0.21 mm in the former and by 0.10 mm in the latter. However, there were no differences in the exposed cartilage or in the effusion volume in the knee joint.

Remarkably, knee pain in the steroid group did not improve significantly compared to the saline-treated patients. The decrease was only 1.2 and 1.9 points over the entire two years. In terms of function and joint stiffness, the effects were the same in both groups.

Four patients in the triamcinolone group reported pain at the injection site after the injection, and two in the saline group. One patient each complained of cellulitis (saline group) and facial flush (triamcinolone group). However, there were no cases of osteonecrosis or subchondral fractures.

Catabolic Effects

Both experimental and clinical studies have now proven the catabolic effects of corticosteroids on cartilage. The present work seems to confirm these findings. According to the authors, this contradicts the hypothesis that inflammation is the driving force behind cartilage destruction, because then steroid therapy should have had a protective effect.

It has been shown several times that saline injections can also improve symptoms of osteoarthritis of the knee. The authors attribute the difference in cartilage loss observed here to the harmful effect of the steroid injections rather than to a possible benefit of the saline injection; after all, previous observational studies would have shown a similar degree of cartilage atrophy. And ultimately, both groups would have benefited from the placebo effect of an injection in the knee.