Background: An intra-articular injection of platelet-rich plasma (PRP) may be an effective treatment for osteoarthritis (OA). However, its efficacy in ankle OA has not been investigated yet. The purpose of this study was to assess the safety and efficacy of an intra-articular injection of PRP in patients with ankle OA during a 24-week period.
Methods: Twenty ankles of 20 patients with varus-type ankle OA who received intra-articular injections of PRP were evaluated. PRP was extracted from whole blood by using the double-spin technique. Three injections of 2-mL PRP were administered to the ankle at an interval of 2 weeks under ultrasonographic guidance. Adverse events and efficacy were assessed at 4, 12, and 24 weeks after the last injection. Clinical outcomes were assessed by using the visual analog scale (VAS) for pain, the Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot scale, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q).
Results: No serious adverse effects were observed during the follow-up period. The VAS and JSSF scale scores significantly decreased from baseline to 4, 12, and 24 weeks after treatment ( P < .001). The mean score in the pain-related subscale of the SAFE-Q significantly improved from baseline to 12 weeks after treatment ( P = .04). Overall, the amount of pain reduction was maximal at 12 weeks after the last injection, and the effect was reduced at 24 weeks. The patients with late-stage OA had worse scores in all outcomes than those with early-stage OA.
Conclusion: Intra-articular injections of PRP resulted in no serious adverse effects and significantly reduced pain in the patients with ankle OA. PRP treatment can be safe and effective and may be an option in the treatment of ankle OA.
Level of evidence: Level IV, case series.
Keywords: ankle osteoarthritis; conservative treatment; platelet-rich plasma (PRP); ultrasonographic guidance injection.