. Which role for synthetic ligaments in the reconstruction of patellar tendon chronic rupture after TKA? Mid-term outcomes using LARS ligament

Background and aim of the work: Patellar tendon rupture is a rare complication after Total Knee Arthroplasty (TKA) which always requires surgical treatment. Patients with chronic lesions or tendon degen- erations showed good results at short-term follow-up (FU) when treated using autografts or allografts, but these techniques showed poor outcomes at long-term FU. Moreover, allografts have high costs and limited availability, not to mention the increased risk of immune reactions and infections. Recently, the use of syn- thetic ligaments for patellar tendon reconstruction has taken hold with encouraging results. We report our experience in the treatment of patellar tendon ruptures after TKA using the Ligament Advanced Reinforce- ment System-LARS®. Methods: Clinical evaluation was performed using the Knee Society Score and record- ing extensor lag. Instrumental evaluation was performed using ultrasound imaging to assess patellar tendon thickness and using conventional x-rays to assess prosthesis’ mobilization signs and patella’s height. Results: At the final FU, 6 knees were included in our study. Patient’s mean age was 66.7. Patellar tendon reconstruc- tion occurred after a mean time of 4 months from the previous surgery. The mean FU was 44,2 months. The mean Knee Score was 63.3 and the mean Function Score was 35. In 4 knees the extensor lag was < 10° while in 2 knees it was > 20°. The mean ISI was 1.16, while the average increment in tendon thickness was 127.12%. Conclusions: In our opinion, synthetic ligaments can be successfully employed for the reconstruction of patel- lar tendon breakage after TKA and rTKA in selected patients, in order to quickly return them to their activity of daily living. (www.actabiomedica.it