Platelet Rich Plasma Injection for Acute Achilles Tendon Rupture: Path-2 Randomised, Placebo Controlled, Superiority Trial

SLR - March 2020 - Caroline Ko

Reference: Keene DJ, Alsousou J, Harrison P, Hulley P, Wagland S, Parsons SR, Thompson JY, O'Connor HM, Schlüssel MM, Dutton SJ, Lamb SE, Willett K. Platelet Rich Plasma Injection for Acute Achilles Tendon Rupture: Path-2 Randomised, Placebo Controlled, Superiority Trial. BMJ. 2019 Nov 20;367:l6132. doi: 10.1136/bmj.l6132. PubMed PMID: 31748208; PubMed Central PMCID: PMC6863552.

Scientific Literature Review

Reviewed By: Caroline Ko, DPM
Residency Program: Kaiser Permanente North Bay Consortium – Vallejo, CA

Podiatric Relevance: Autologous platelet rich plasma (PRP) is an arising modality often added to augment and presumably accelerate healing with supraphysiological concentrations of platelets, leukocytes, and growth factors. The market for the product is projected to be worth US $383.56 million by 2023. Yet, the scientific evidence on the clinical efficacy has been weak, underpowered and mostly anecdotal. Although platelet rich plasma may positively affect cellular and physiologic healing, quality of clinical efficacy is increasing in its popularity after being endorsed by athletes and leading to increased medical costs for the patients. This study was conducted to determine whether PRP improves outcomes after acute Achilles tendon rupture treated with conservative treatment.

Methods: This randomized, placebo-controlled superiority trial was conducted at 19 hospitals in the United Kingdom. Two hundred thirty adults over the age of 18 years who presented within 12 days of acute Achilles tendon rupture injury and were conservatively treated were included. Excluded were those with injuries at the insertion or musculotendinous junction, major leg injury or deformity, Diabetes, platelet or hematologic disorder, systemic corticosteroids, anticoagulation treatment and other contraindicating conditions. Patients were randomized 1:1 to PRP (n=114) or placebo with dry needle (n=116). The primary outcome of the study was Achilles tendon function at 24 weeks, measured by the limb symmetry index (injured/uninjured x100) during the heel rise endurance test (repeated single leg heel rises until fatigue). Secondary outcomes were patient reported outcomes such as, Achilles tendon rupture score, quality of life (short form 12), pain (visual analog score), patient specific function goal attainment and adverse events. Data from the study were analyzed on the intention to treat basis.

Results: At 24 weeks post-injury, no significant difference was detected neither the primary or the secondary outcomes in patients who received PRP injections and placebo injections. Muscle tendon function in patients who received PRP injections (34.7 percent; SD 17.7 percent) and placebo injections (38.5 percent; SD 22.8 percent) had adjusted mean difference of -3.9 percent.

Conclusions: This trial is allegedly the largest known trial that investigated into the efficacy of PRP in acute tendon ruptures. There currently is no solid evidence that PRP injections can objectively improve muscle tendon function or patient reported outcomes after acute Achilles tendon injuries treated with conservative treatments, and that conclusion is supported in this trial. This may caution podiatric surgeona in the future from utilizing treatment modalities not confirmed with research.