In patients with painful hip osteoarthritis, an intramuscular glucocorticoid injection may effectively alleviate hip pain in the short-term, according to a study published in the Annals of Rheumatic Diseases.
For this study, 106 patients who had symptomatic hip osteoarthritis for ≥6 months and moderate to severe hip pain (score ≥3 on a 10-point numeric rating scale [NRS]) were randomly assigned to receive a glucocorticoid (40 mg triamcinolone acetate; n=52) or saline (n=54) injection in the gluteus muscle. Patients, researchers, treating physicians, research assistants, and outcome assessors were all blinded to injections.
Hip pain severity 2 weeks after injection, assessed with the NRS and the 100-point Western Ontario and McMaster University Osteoarthritis Index pain (WOMAC) subscale, at rest and during walking was the study’s primary outcome. An intention-to-treat analysis was also conducted at 2, 4, 6, and 12 weeks.
Participants who had received the glucocorticoid vs saline injection reported hip pain reductions at 2 weeks at rest, using the NRS (between group difference, −1.3 point; 95% CI, −2.3 to −0.3; P =.01). There was no significant difference between the groups in terms of hip pain during walking assessed with the NRS (between-group difference, −0.9) or using the WOMAC pain scale score (range, 0-100) at the 2-week follow-up.
Reductions in hip pain at rest, assessed with the NRS, were maintained 4 weeks (between-group difference, −1.2; 95% CI, −2.1 to −0.2; P =.01), 6 weeks (between-group difference, −1.4; 95% CI, −2.4 to −0.5; P =.005), and 12 weeks (between-group difference, −1.2; 95% CI, −2.3 to −0.2; P =.02) after glucocorticoid injection. Hip pain during walking, also assessed with the NRS, was reduced at 4 weeks (between-group difference, −1.1; 95% −2.0 to −0.2; P =.01), 6 weeks (between-group difference, −1.4; 95% CI, −2.3 to −0.4; P =.004), and 12 weeks (between-group difference, −1.3; 95% CI, −2.2 to −0.3; P =.01) after glucocorticoid injection.
The WOMAC function score (range, 0-100) indicated an improvement at 4 weeks (between-group difference, −9.3; 95% CI, −17.2 to −1.4; P =.02), 6 weeks (between-group difference, −8.2; 95% CI, −16.5 to 0.1; P =.05), and 12 weeks (between-group difference, −8.9; 95% CI, −17.6 to −0.1; P =.05) after glucocorticoid vs placebo injection. Stiffness, assessed with the WOMAC stiffness scale, was also improved at 6 and 12 weeks after glucocorticoid vs placebo injection.
A limitation of this study was the assessment of only 1 injection, resulting in the lack of evaluation of whether multiple injections would provide a greater effect on hip pain.
“The administration of an [intramuscular] injection is much easier than an [intra-articular] hip joint injection without the need for ultrasound/radiologic guidance and can, therefore, be performed in both secondary and primary care,” concluded the study authors.
Reference
Dorleijn DMJ, Luijsterburg PAJ, Reijman M, et al. Intramuscular glucocorticoid injection versus placebo injection in hip osteoarthritis: a 12-week blinded randomised controlled trial [published online March 7, 2018]. Ann Rheum Dis. doi: 10.1136/annrheumdis-2017-212628