Abstract
INTRODUCTION: Epicondylitis (lateral and medial) is a common tendinopathy that impairs function and quality of life. Corticosteroid injections (CSI) provide rapid but often short-lived symptom relief, while platelet-rich plasma (PRP) is used as a biologic alternative aimed at tendon regeneration. Comparative effectiveness between PRP and CSI remains uncertain in real-world settings. MATERIALS AND METHODS: We conducted a retrospective cohort study using de-identified electronic health records from the TriNetX Network (2010-2025). Adults ≥18 years with coded epicondylitis and subsequent PRP or CSI were included. Cohorts were 1:1 propensity-score matched on demographics and comorbidities (age, sex, race, type 2 diabetes, obesity, hypothyroidism, nicotine dependence). Outcomes were assessed over a period of 1 year after the index event and included repeat or new medication, opioid exposure, long-term opioid initiation, visits to the emergency department (ED), functional diagnoses (stiffness, weakness, mobility), physical therapy (PT) utilization, and surgical escalation. Hazard ratios (HRs) and risk ratios were estimated. RESULTS: After matching, 1,064 PRP patients were compared with 1,064 CSI patients. PRP was associated with higher hazards of repeat or new medication (HR 1.33; 95% CI 1.18-1.50; RR 1.21), opioid exposure (HR 1.48; 95% CI 1.20-1.83; RR 1.43), PT utilization (HR 1.52; 95% CI 1.27-1.81; RR 1.41), joint stiffness (HR 1.64; 95% CI 1.04-2.59; RR 1.63), dependence on mobility aids (HR 3.63; 95% CI 1.80-7.31; RR 3.60), and surgical escalation (HR 2.57; 95% CI 1.19-5.56; RR 2.30). No significant differences were observed for ED visits, long-term opioid initiation, abnormal gait, muscle weakness, or contracture. CONCLUSION: In this large, multi-institutional real-world cohort, PRP was associated with higher short-term utilization and treatment failure risks compared with CSI. While randomized trials suggest mid-term benefits of PRP, our findings highlight an efficacy-effectiveness gap, likely reflecting heterogeneity in PRP protocols and patient selection. Clinicians should counsel patients about the potential for early symptom flare and higher downstream resource use when considering PRP.