SLR - July 2015 - Anthony Rizzardi
Double-blind, Randomized, Placebo-controlled Study Evaluating the Use of Platelet-rich Plasma Therapy (PRP) for Acute Ankle Sprains in the Emergency Department
Reference: Rowden A, Dominici P, D'Orazio J, Manur R, Deitch K, Simpson S, Kowalski MJ, Salzman M, Ngu D. Double-blind, Randomized, Placebo-controlled Study Evaluating the Use of Platelet-rich Plasma Therapy (PRP) for Acute Ankle Sprains in the Emergency Department. J Emerg Med. 2015 Jun 2.
Scientific Literature Review
Reviewed By: Anthony Rizzardi, DPM
Residency Program: Pinnacle Health
Podiatric Relevance: Platelet-rich plasma (PRP) is an autologous concentration of platelets that is thought to improve healing by promoting inflammation through growth factor and cytokine release. PRP is a commonly used modality by podiatric surgeons for various foot and ankle conditions. One such condition where platelet-rich-plasma may be utilized is ankle ligament strains/sprains. Over 23,000 people per day require treatment for ankle sprains. Studies to date have shown mixed results, with few randomized trials. The authors of this study looked to determine patient function among patients randomized to receive standard therapy plus PRP, compared to patients who receive standard therapy plus placebo injection.
Methods: Patients with severe ankle sprains were randomized. Severity was graded on degree of swelling, ecchymosis, and ability to bear weight. PRP with lidocaine and bupivacaine was injected at the point of maximum tenderness by a blinded physician under ultrasound guidance. The control group was injected in a similar fashion with sterile 0.9% saline. Both groups had visual analog scale (VAS) pain scores and Lower Extremity Functional Scale (LEFS) on days 0, 3, and 8. LEFS and a numeric pain score were obtained via phone call on day 30. All participants were splinted, given crutches, and instructed to not bear weight for 3 days; at this time patients were reevaluated.
Results: Over a period of 1 year there were 1156 patients screened and 37 were enrolled. Four withdrew before PRP injection was complete; 18 were randomized to PRP and 15 to placebo. There was no statistically significant difference in VAS and LEFS scores between groups at days 0, 3, and 8. There also was no significant statistical difference noted on LEFS and numeric pain scores at day 30.
Conclusions: In this prospective, randomized, double-blinded, placebo-controlled trial, PRP did not provide benefit in either pain control or function over placebo for acute ankle sprains. Furthermore, given the limited number of participants in the study, the results remain speculative. As PRP injections have been shown beneficial in the treatment of various other foot and ankle conditions, further research should be conducted using proper control groups, randomization, blinding, and validated disability outcome measures for pain and function to assess the validity of PRP for treatment of acute foot and ankle injuries such as ankle sprains.