Platelet-rich plasma administration to reduce surgical interventions and improve functional outcomes in patients who have failed physical therapy

The benefit of platelet-rich plasma (PRP) injections for foot and ankle conditions remains controversial. No studies have evaluated validated Patient Reported Outcomes Measurement Information System (PROMIS) measures of physical function (PF) and pain interference (PI) following PRP. Because PROMIS is validated in foot and ankle and exhibits improved reliability and generalizability compared to other commonly used patient-reported metrics, this study aimed to investigate functional outcomes measured by PROMIS following PRP for foot and ankle pathologies. This investigation was a retrospective study of all 81 patients who underwent PRP therapy for any foot and ankle pathology at a single institution (2018-2023). All patients had PRP for any foot and ankle pathology after failing 6-8 weeks of physical therapy and prior to any surgical intervention. 81 patients were contacted via phone and email up to five attempts to complete surveys containing PROMIS, as well as additional questions regarding ability to increase activity compared to pre-injection baseline and whether PRP injection was worth out-of-pocket costs. PROMIS was developed for a US population mean score of 50. Higher PF indicates better physical function, whereas higher PI designates more pain. Primary outcome was PROMIS PF and PI. Secondary outcomes were ability to increase activity compared to pre-injection baseline, self-reported pain resolution, whether surgery was pursued, and whether patients believed PRP was worth out-of-pocket costs. Mean follow-up was 28 months. Across all pathologies, mean PROMIS PF and PI were 49.1±7.3 and 51.6±8.5, respectively. Patients with plantar fasciitis (N=4) had highest average PF (58.2±6.0) and lowest average PI (42.9±5.4). Insertional Achilles tendinosis (N=6) and non-insertional Achilles tendinosis (N=7) exhibited average PFs of 50.8±5.3 and 50.2±4.4, respectively, and PIs of 46.4±7.2 and 49.7±5.7, respectively. Average PF and PI by pathology were, respectively, peroneal tendinosis 45.8±3.8 and 56.0±8.3, posterior tibialis tendinosis 49.0±4 and 50.8±10.4, and ankle arthritis 48.0±9.5 and 53.5±7.2. 75% (N=35/47) of patients increased activity following PRP. 23% (N=11/47) had complete resolution of pain after PRP. 83% (N=39/47) did not pursue surgery following PRP. 77% (N=36/47) agreed that PRP was worth the out-of-pocket cost. Most patients who received PRP for various foot and ankle pathologies scored population mean PROMIS scores, increased activity, avoided surgery, and believed PRP was worth out-of-pocket costs. While our results may suggest a potential role for PRP to be offered as a reasonable nonoperative treatment option for foot and ankle pathology, further studies with larger samples are needed to evaluate PROMIS after PRP.