A systematic review of the outcomes of partial ulnar collateral ligament tears of the elbow in athletes treated non-operatively with platelet-rich plasma injection

Background: This study aimed to analyze the effects of platelet-rich plasma (PRP) for partial ulnar collateral ligament (UCL) tears in athletes and predicted positive outcomes. Methods: The researchers systematically reviewed the PubMed, Cochrane CENTRAL, MEDLINE, Scopus, and Google Scholar databases to identify studies with clinical outcomes of PRP for partial UCL tears. They excluded studies that did not stratify data by tear type or included surgical management. Results: Five studies with 156 patients were included. The timing, amount, platelet concentration, type, and number of PRP injections were highly variable among the studies. However, 75% (n = 97/127) of athletes returned to sport (RTS) at a weighted average of 82.1 days (37–84) after PRP injection. One study showed significant improvements in patient-reported outcomes. Two studies showed positive outcomes in the modified Conway scale, complete reconstitution of the UCL in 87% of patients on MRI, and significant improvement in the humeral-ulnar joint space after PRP injection via ultrasound. The Coleman methodology score (CMS) averaged 48/100, indicating an overall poor quality of evidence. Conclusion: This review demonstrates favorable RTS, clinical, and radiographic outcomes in patients receiving PRP for partial UCL tears, but the literature remains heterogeneous and of low quality. Level of Evidence: III.