BIOlogic Augmented Repair of Complex Anal Fistula Using Acellular Matrix and/or Autologous Platelet-rich Plasma

Control patients will receive usual standard of care surgical repair of their complex fistula by LIFT or advancement flap technique without any biologic adjunct.

Participants will have 40-50cc of peripheral whole blood drawn into a syringe pre-loaded with acid citrate dextrose (ACD) anticoagulant and concentrated PRP harvested by double centrifugation technique using the manufacturer's kit and benchtop centrifuge. This typically yields 5-8cc of PRP that is 18-times more concentrated than baseline.

"Participants will receive 200g of paste matrix and 200g injected at the following sites: the internal opening closure site at level of the sphincter muscle, within the walls of the fistula tract along its length, and within the tissue of an advancement flap particularly at areas of tissue apposition."