Paper 58: The Use of Intraoperative Platelet Rich Plasma Increases the Risk for Heterotopic Ossification in Patients Undergoing Primary Hip Arthroscopy

OBJECTIVES: Platelet-rich-plasma (PRP) is becoming an increasingly popular biologic treatment to enhance healing in quality of tissue and/or speed of recovery. While many use PRP to avoid surgery, some use PRP as an adjunct intraoperatively to accelerate healing and recovery. While there are few reports of "complications" associated with PRP injection, there are anecdotal reports of heterotopic ossification associated with PRP use, particularly in the treatment of core muscle injury. There is, however, little data regarding its safety profile in hip arthroscopy. METHODS: We queried the IBM® MarketScan® Research databases (formerly Truven Health Analytics) to identify patients who underwent hip arthroscopy from 2007 to 2015. This database is a collection of commercial inpatient, outpatient, and pharmaceutical claims of more than 75 million employees, retirees, and dependents representing a substantial portion of the U.S. population covered by employer-sponsored insurance. Patients that underwent hip arthroscopy were stratified into groups based on whether or not they received platelet rich plasma during their surgery. Complications and reoperations for both groups were assessed for 90 days after surgery. Patients without laterality codes were excluded to assure any complications and/or reoperations were on the operated extremity. A multivariate logistic regression analysis was used to control for confounding factors. RESULTS: 35,263 patients met the inclusion criteria of this study, of which 253 (0.7%) received PRP at the time of hip arthroscopy. Age and rates of diabetes, hypertension, hyperlipidemia, obesity, and tobacco use were similar between cohorts. However, there were significant differences in the concomitant procedure distribution. Unadjusted composite complications rates were significantly different between the two cohorts (arthroscopy only 7.9%, arthroscopy + PRP 14.2%, p = 0.0002). Heterotopic ossification was the main driver of this difference, occurring more commonly in the PRP cohort (10.7% vs 5.7%, p = 0.0006). When stratifying by procedure type, intraoperative PRP was associated with higher complications in patients undergoing femoroplasty (25.0% vs 10.4%, p < 0.0001), labral repair (18.8% vs 9.2%, p = 0.0002), and acetabuloplasty (20.3% vs 10.8%, p = 0.0009). In multivariate regression analysis, after controlling for all other variables, PRP did lead to higher rates of postoperative complications after hip arthroscopy (ref: no PRP, OR 1.9, 95% CI 1.3 – 2.7, p = 0.0003.). Unadjusted reoperation rate at 90 days was similar between cohorts (arthroscopy 3.5% vs PRP 4.0%, p = 0.6757) but through 2-years patients who received PRP had higher re-operation rates (13.0% vs 9.3%, p = 0.0381). CONCLUSIONS: Patients receiving intraoperative PRP during hip arthroscopy were at increased risk of developing a post-operative complication, particularly heterotopic ossification. Consideration should be made on which patients may benefit the most from PRP. Further reserach is needed to determine the pathophysiology of heterotopic ossification related to platelet rich plasma, and to elucidate whether or not a link exists between the biochemical process of heterotopic ossification and PRP.