Paper #19 - ISHA Annual Scientific Meeting 2016

Outcomes of Intra-articular Corticosteroid Injections for Adolescents with Hip Pain

Jennifer Tangtiphaiboontana, MD, San Francisco, CA UNITED STATES
Alan L. Zhang, MD, San Francisco, CA UNITED STATES
Nirav Pandya, MD, San Francisco, CA UNITED STATES

University of California, San Francisco Medical Center, San Francisco, CA, UNITED STATES

FDA Status Not Applicable

Summary: Fluoroscopic guided corticosteroid hip injection may have limited efficacy for therapeutic treatment of hip pain secondary to FAI in adolescents as 67% of patients required surgical intervention within 14 months of injection. However, for adolescents without FAI, 88% improved with CSI alone (despite MRI diagnosis of labral tear) and did not require further treatment within 2.5 years.

Introduction: Conditions such as femoroacetabular impingement (FAI) and labral tears have received increased attention as causes of hip pain in the pediatric and adolescent populations. Intra-articular injection of corticosteroid and anesthetic (CSI) under fluoroscopic guidance is a useful tool for localization of pain secondary to an intra-articular process; however, the effectiveness of CSI as a stand-alone treatment for hip pain in adolescent patients is unknown. The purpose of this study is to evaluate the use of intra-articular CSI for the treatment of hip pain in adolescents and determine factors that may affect outcomes after injection. Methods: We performed a retrospective chart review of adolescent patients who underwent fluoroscopic guided hip injection with corticosteroid for treatment of hip pain at a single institution from 2012 to 2015. Anesthesia was used for patient comfort and physical examination of the hip. Each injection consisted of 40 mg of kenalog, 3 mL of 1 percent lidocaine, and 3 mL of 0.125 percent bupivacaine. Patients were tracked to assess outcomes after injection including conversion to surgical intervention. Variables including gender, age, prior history of hip surgery, radiographic findings on x-ray and magnetic resonance imaging (MRI), and pre-injection and intraoperative hip range of motion (ROM) were analyzed. Statistical analysis was performed using the chi-squared test and the fisher exact test. Results: A total of 26 hips in 23 patients (18 females, 5 males) underwent fluoroscopic guided CSI under anesthesia. The mean age at time of injection was 15.7 years (range 13 – 19). Diagnostic imaging revealed osseous lesions consistent with FAI (cam or pincer deformity) in 18 hips and labral tears in 20 hips. With mean follow-up of 32 months, fifty-four percent (14/26 hips) went on to surgical intervention after the injection. Thirteen hips were treated arthroscopically while one required an open femoral and pelvic osteotomy. Average time to surgical conversion was 15.7 months after CSI. There was no difference in gender, age, history of prior hip surgery, hip ROM or presence of labral tears between patients that underwent surgery and patients that improved with CSI alone. Cam or pincer deformities consistent with FAI were present in 93% (13/14 hips) of the operative group as 72% (13/18 hips) with osseous deformity would undergo surgical treatment. Patients with FAI were more likely to need surgical intervention than patients without FAI (RR= 5.8, 95% CI 0.9-36.0, p = 0.009) but presence of a labral tear did not affect risk for surgical intervention as 88% (7/8 hips) with labral injury on MRI but no osseous lesion improved with CSI alone. Conclusion: Fluoroscopic guided corticosteroid hip injection may have limited efficacy for therapeutic treatment of hip pain secondary to FAI in adolescents. However, for adolescents without osseous deformity, CSI may offer prolonged improvement of symptoms even in the presence of labral tears.