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 4ml of 0.5% bupivacaine and 1ml of triamcinolone acetate (40mg/1ml). 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 preinjection 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.