Paper 17: Follow-Up of Heterotopic Ossification (HO) After Platelet-Rich Plasma (PRP) for Groin Injuries

Abstract

Objectives:A 2015 study of PRP for groin injuries in NFL players* alerted us to the possibility of PRP causing heterotopic ossification. This study of athletes seen from 2014 to 2019 provides a more comprehensive analysis of that observation.Methods:All athletes seen at one institution and identified at their first visit as having received PRP for a core muscle injury were followed and compared to core muscle injury patients who had not previously received PRP. HO was observed on MRI and intraoperatively and confirmed pathologically. All PRP patients were followed for at least two years.Results:PRP patients had a 40.7% occurrence of HO, compared to 0.7% in the non-PRP cohort (See Table). Three athletes who had PRP retired early from their sports due to the HO and scar issues. The occurrence of HO did not correlate with any technique of PRP administration. Twenty-two of 28 (78.6%) NFL players who received PRP developed HO, compared to 0 (0%) in 28 NFL randomly selected, age-, position- and injury matched controls. Three-month “success” rates were 67.9% and 96.4% respectively in the two groups (p<0.006) in terms of return to play at previously high-level levels of performance or greater, according to their own subjective assessments. Differences were mostly due to scar issues. Most “failure” patients in the PRP group had returned to play but not at their previously high levels.Conclusions:This longer-term, more comprehensive study confirms the previous preliminary analysis that caregivers should take a cautious approach to treatment with PRP for groin injuries.NoneNoneNoneTable 1.Univariable and multivariable logistic regression models predicting a final graft diameter of 8mm or more. Significant predictors are indicated in bold. 95%CI: 95% Confidence interval, BMI: body mass index.