IRCT20200307046714N1 IRCT 2022-01-15 Shahid Beheshti University of Medical Sciences The effect of platelet rich plasma in lateral ankle sprain The effect of platelet rich plasma (PRP) on pain and function in patients with lateral ankle sprain after modified Brostrom surgery, a randomized clinical trial 2022-01-20 anticipated 20 Complete https://irct.ir/trial/60702 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Randomization description: Randomization was performed using an online block randomization tool (www.sealedenvelope.com), with a variable block size of 2 or 4, and stratified based on age (≥40 or < 40 years), Blinding description: Evaluation of the outcomes will be performed by a foot and ankle surgeon who is unaware of patients’ randomization. The physiotherapist who will prescribe the physiotherapy program and the researchers who will perform the statistical analysis will also be blinded to the randomization. N/A lateral ankle sprain. Intervention 1: Intervention group: In this group of patients, 50 ccs of peripheral blood will be taken from each patient by a 50cc syringe in the first, second, and sixth weeks after surgery, then centrifuged and converted to 5 ccs PRP. The first PRP solution will be injected into the site of lateral ligament surgery under ultrasound guide by a physician. The second and third injections will be also injected into the tibiotalar joint by the same physician under ultrasound guide. Intervention 2: Control group: This group receives only routine treatment after surgery. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is There is no more information.