IM or IA glucocorticoid injection, which is better for reducing pain in knee osteoarthritis?

Netherlands: Both intramuscular (IM) glucocorticoid injection and intra-articular (IA) glucocorticoid injection should be considered effective strategies for patients with knee osteoarthritis (OA), suggests findings from a trial. And, a shared decision-making process should take place between clinicians and knee OA patients in cases when a glucocorticoid injection is indicated. The study appears in JAMA Network Open. 

"IM glucocorticoid injection could present an inferior effect in reducing pain at 4 weeks compared with IA injection in patients with knee OA in primary care," Qiuke Wang, Erasmus MC University Center Rotterdam, Rotterdam, the Netherlands, and colleagues wrote in their study. "Noninferiority of an IM injection was seen at 8 and 24 weeks after injection. The trial provides data for shared decision-maling considering the advantages and disadvantages of injection types."

IA glucocorticoid injection is widely used in knee OA patients but the safety of this technique is questionable. An alternative approach could be IM glucocorticoid injection. The study therefore was conducted to investigate whether an IM glucocorticoid injection is noninferior to an IA glucocorticoid injection in reducing knee pain for patients with knee OA in primary care in KIS trial.

KIS is a multicenter, open-label, randomized clinical noninferiority trial. It included patients with symptomatic knee OA and was conducted in 80 primary care general practices in the southwest of the Netherlands. The study was conducted from March 1, 2018, to July 28, 2020. 

Patients were randomly allocated to receive an injection of triamcinolone acetonide, 40 mg, either IM in the ipsilateral ventrogluteal region or IA in the knee joint and were followed for 24 weeks.

The pain score at 4 weeks were measured with Knee Injury and Osteoarthritis Outcome Score (range, 0-100; 0 indicates extreme pain). A per-protocol analysis was prespecified as the primary analysis.

Of 145 patients included in the trial; 138 patients (IM, 72; IA, 66) were included in the per-protocol analysis. 

The authors concldued, "Both types of injection should be considered effective strategies, and this trial provides evidence for shared decision-making between clinicians and patients, taking into account the advantages and disadvantages of both treatment strategies."

Reference:

Wang Q, Mol MF, Bos PK, et al. Effect of Intramuscular vs Intra-articular Glucocorticoid Injection on Pain Among Adults With Knee Osteoarthritis: The KIS Randomized Clinical Trial. JAMA Netw Open. 2022;5(4):e224852. doi:10.1001/jamanetworkopen.2022.4852