Platelet-rich plasma injections = placebo in patients with nonsurgically treated acute Achilles tendon ruptures

Reference

Boesen AP, Boesen MI, Hansen R, et al. Effect of platelet-rich plasma on nonsurgically treated acute achilles tendon ruptures: a randomized, double-blinded prospective study. Am J Sports Med 2020;48(9):2268-2276.

Synopsis

These authors recruited adult patients (18 to 60 years of age) with a suspected acute Achilles tendon rupture who were evaluated in emergency departments in Denmark within 72 hours of their injury. The patients had their ruptures confirmed by clinical examination and ultrasound. All patients were treated with a continuously worn ankle orthosis that kept the foot plantar flexed for 8 weeks. After the orthosis was applied, the patient was allowed to bear weight. Every 2 weeks, the researchers lessened the degree of plantarflexion. Once the orthosis was removed, the patients wore shoes with a standard 1-cm heel cap. After 9 weeks, all patients began an ankle rehabilitation program designed to improve mobility, balance, plantar flexor function, and strength. The researchers randomized patients to receive 4 ultrasonically guided injections of PRP (n = 20) or isotonic saline (n = 20). They injected the patients every 2 weeks starting within 4 days of the injury. They explicitly told the patients not to look away. (I'm not sure why, but the authors felt they had to include that in the methods.) They evaluated the patients' outcomes at the time of removing the orthosis and again at 3, 4.5, 6, 9, and 12 months after the injury. None of the patients, injecting clinicians, outcome assessors, or statisticians knew which patients received PRP or placebo. One patient in each group re-ruptured their Achilles and dropped out of the study. Based on a variety of measures that included pain, function, mobility, return to activity, range of motion, and so forth, the patients in each group improved at each point in time, and the degree of improvement was similar. After one year, the patients in both groups still had minor and probably not significant functional impairment in the injured ankle compared with the uninjured ankle. The authors did not report rates of adverse events.