Pilot Study of Ultrasound-Guided Corticosteroid Hip Injections by Emergency Physicians

INTRODUCTION Our objective was to assess the efficacy of ultrasound-guided hip injections performed by emergency physicians (EPs) for the treatment of chronic hip pain in an outpatient clinic setting. METHODS Patients were identified on a referral basis from the orthopedic chronic pain clinic. The patient population was either identified as having osteoarthritis of the hip, osteonecrosis of varying etiologies, post-traumatic osteoarthritis of the hip, or other non-infectious causes of chronic hip pain. Patients had an ultrasound-guided hip injection of 4 ml of 0.5% bupivacaine and 1 ml of triamcinolone acetate (40 mg/1 ml). Emergency medicine resident physicians under the supervision of an attending EP performed all injections. Pain scores were collected using a Likert pain scale from patients prior to the procedure, and 10 minutes post procedure and at short-term follow-up of one week and one month. The primary outcome was patient-reported pain score on a Likert pain scale at one week. RESULTS We performed a total of 47 ultrasound-guided intra-articular hip injections on 44 subjects who met inclusion criteria. Three subjects received bilateral injections. Follow-up data were available for 42/47 (89.4%) hip injections at one week and 40/47 (85.1%) at one month. The greatest improvement was at 10 minutes after injection with a mean decrease in Likert pain score from pre-injection baseline of 5.57 (95% CI, 4.76-6.39). For the primary outcome at one week, we found a mean decrease in Likert pain score from pre-injection baseline of 3.85 (95% CI, 2.94-4.75). At one month we found a mean decrease in Likert pain score of 1.8 (95% CI, 1.12-2.53). There were no significant adverse outcomes reported. CONCLUSION Under the supervision of an attending EP, junior emergency medicine resident physicians can safely and effectively inject hips for chronic pain relief in an outpatient clinical setting using ultrasound guidance.