Percutaneous ultrasonic tenotomy effectively debrides tendons of the extensor mechanism of the knee: A technical note

Background: Percutaneous ultrasonic tenotomy (PUT) is a minimally-invasive method of treating patellar tendinosis, but its immediate effect on tendon structure has never been studied. Given the crucial nature of the extensor mechanism of the knee, it is important to understand the procedure's effect on tendon structure prior to clinical implementation. The aim of this study was to analyze the tendon structure of the extensor mechanism of the knee after PUT in a cadaveric model. Methods: Four fresh-frozen cadaveric specimens (two patellar and two quadriceps tendons) underwent PUT. The tendons were then sectioned and stained with hematoxilin & eosin (H&E). The sections were analyzed for a clear area of debridement. The area of debridement was calculated as an average of three measurements. Results: All four tendons demonstrated a clear area of debridement limited to the treatment area without damaging any surrounding tissue. The area of debridement for the patellar and quadriceps tendons treated was 2.89 mm2, 15 mm2, 2.98 mm2 and 7.29 mm2, respectively. Conclusions: Percutaneous ultrasonic tenotomy effectively debrided the treatment area in all tendons without damaging surrounding tissue. Further work is needed to report clinical outcomes, assess the risk of post-procedure tendon rupture and define return-to-sport progression. (C) 2020 Elsevier B.V. All rights reserved.