Triamcinolone hexacetonide (TH), triamcinolone acetonide (TA), and methylprednisolone acetate (MPA) are the most frequently used steroid preparations. As per evidences,  intra-articular TH is more efficacious than MPA and TA in chronic inflammatory arthritis. However, it is not sure which one of these preparations is more effective. Kumar A, et al. conducted a double-blind, randomized controlled trial to distinguish intra-articular knee injections of MPA and TA in patients with chronic inflammatory arthritis.

The patients with rheumatoid arthritis or spondyloarthritis with an acutely swollen knee joint (≥1 week, <24 weeks) were considered. Patients were randomly designated (1:1) to intra-articular knee injection with MPA or TA (80 mg, 2 mL of each). At 4, 12, and 24 weeks, the evaluations were executed. The primary outcome was the time to relapse (Kaplar-Meier) over 24 weeks, with relapse defined as the return to baseline pain or swelling ≥1 week. The change in pain and swelling (using a numerical rating scale), range of movement, and occurrence of adverse effects were the secondary outcomes. The primary assessment was aimed to treat, with last observation carried forward.

A total of 100 patients (89 with rheumatoid arthritis) were randomly assigned in equal numbers to the MPA and TA groups. Over 24 weeks, 9 patients relapsed in each group. The mean time to relapse was not significantly different for the MPA and TA groups (20.8 [95% CI, 18.8-22.7] weeks and 20.9 [95% CI, 19.0-22.8] weeks, respectively; P = 0.9; hazard ratio = 1.0 [95% CI, 0.4-2.5]). There were no significant intergroup differences; although, there was a significant reduction in pain and swelling scores at all visits (p< 0.001). The mean change in pain in MPA (-4.4 [3.1]) and TA groups (-3.9 [2.8]) was not significantly different (P=0.46) at 24 weeks. No infection, hematoma or hypopigmentation was observed in any patient. Also, no notable intergroup differences were found in joint swelling, the range of movement, modified (28 joint) Disease Activity Score using 3 variables, or Health Assessment Questionnaire over 24 weeks.

It can thus be indicated that no significant differences were found in efficacy between intra-articular knee injections with MPA and TA in with chronic inflammatory arthritis. However, the consequences need to be extrapolated cautiously due to the small sample size. At 24 weeks, three-quarters of the patients remained relapse free.