An intramuscular gluteal injection of triamcinolone acetate reduced hip pain at the 2-week follow-up in patients with hip osteoarthritis compared with placebo, according to results of a double-blind study reported at the 2016 Osteoarthritis Research Society International (OARSI) World Congress.
“Intramuscular corticosteroid injection is an effective method to reduce patients’ pain in hip osteoarthritis for a period of at least up to 12 weeks,” stated lead author Desirée M. Dorleijn, MD, Erasmus University Medical Center, Rotterdam, Netherlands, at a poster presentation here on April 1.
Dr. Dorleijn said that, while intra-articular corticosteroid injections are often recommended in guidelines, “injection into the hip joint is challenging and needs ultrasound or fluoroscopic guidance…[which makes it] almost impossible in general practice.” An intramuscular injection might be less complex, she suggested.
Dr. Doleijn and colleagues randomised a total of 107 patients (106 of whom were included in the intention-to-treat [ITT] analysis) with hip osteoarthritis who had been both clinically (as per American College of Rheumatology [ACR] criteria) and radiographically assessed (Kellgren-Lawrence grade 2 or higher) and who, despite using oral analgesics, still had hip pain of severity 3 or higher (scale of 0 to 10, with 0 = no hip pain). In all, 70% of patients had had symptoms for at least 1 year. A total of 68% were female, and the mean age was 64 years.
Study treatment was either triamcinolone acetate 40 mg (n = 52) or placebo (n = 54), via a single intramuscular injection into the gluteus muscle ipsilateral to the hip with osteoarthritis.
The investigators evaluated differences between the 2 treatment groups using linear mixed models and repeated measures, with adjustments for variables that changed the effect estimate >10%.
The primary outcome was defined as severity of hip pain at 2 weeks. On a numeric rating scale (NRS; 0 to 10, with 0 = no pain), hip pain at rest was found to be significantly lower with the corticosteroid treatment compared with placebo at 2 weeks (difference: -1.3 points, 95% confidence interval [CI]: -2.3 to -0.3, P = .01). The difference remained significant at the 4, 6, and 12 week visits. Pain during walking also showed a numerically lower score on the NRS with active treatment versus placebo, which was, however, not significant at 2 weeks (P = .07), but was significant at 4, 6, and 12 weeks.
On the pain subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC; 0 to 100, with 0 = no pain), pain was rated as lower among corticosteroid-treated patients compared with placebo at all follow-up time points; however, it did not reach statistical significance until weeks 6 and 12.
The investigators assessed pain using the Intermittent and Constant Osteoarthritis Pain (ICOAP), which was significantly lower at all follow-up time points after the corticosteroid injection compared with placebo, for the intermittent and constant subscores as well as the total score.
Dr. Dorleijn noted that neither adverse events nor the need for medical cointerventions (e.g. oral analgesics, healthcare visits) differed between the 2 treatment groups.[Presentation title: Intramuscular Corticosteroid Injection Versus Placebo Effective In Pain Reduction In Patients With Hip Osteoarthritis. Abstract 310]