Avulsion fracture of the inferior pole of the patella treated by transosseous reattachment: A case report

Abstract

Introduction and importance: Avulsions of the patella apex corresponding to patellar ligament ruptures are rare and present a challenge in terms of treatment strategy. Avulsion fractures of the patella apex are a rare clinical entity, but one that should not be misdiagnosed. Surgical management requires careful therapeutic planning. The aim of our study was to present a clinical entity that should not be misdiagnosed and to outline therapeutic strategies. Case report: A 45-year-old patient with no particular medical history suffered an avulsion fracture of the apex of the right patella after falling down the stairs at work. Surgical treatment consisted of reinserting the patellar tendon after lacing with Vicryl 2 using Krakow sutures and drilling transosseous tunnels to allow reinsertion of the patellar tendon. To protect the suture, a wire metal cage was placed with a tunnel at the tibial bone and trans-quadricipital passage at the base of the patella, with the knee held at 30° flexion. Immobilization with a knee brace was carried out for 6 weeks. Partial weight-bearing was authorized after 3 weeks, and full weight-bearing after 6 weeks, followed by functional rehabilitation for more than 6 months with post-operative X-rays showing consolidation of the distal fragment adjacent to the patellar ligament. At the 2-year follow-up, moderate knee stiffness was noted with a Lysholm score of 68 and slight amyotrophy of the right quadriceps. Conclusion: Avulsion fractures of the distal pole of the patella remain rare injuries, but their diagnosis should not be underestimated. Reinsertion of the patellar tendon to the remainder of the patella using transosseous tunnels provides excellent long-term outcomes, although patella baja may explain postoperative stiffness in patients.