Complete Traumatic Trifocal Failure of the Extensor Mechanism of the Knee: A Case Report and Review of the Literature

Abstract

The unique case of a rare 3-level extensor mechanism failure in a 28-year-old male, involving a tibial tubercle avulsion fracture, a patellar tendon avulsion off the tibial tubercle fragment, and a severely comminuted patella fracture, and the surgical technique required to repair such an injury is presented. Focus is spent on the unique repair of a tendon injury when both proximal and distal bony attachments are damaged. Trifocal knee extensor mechanism is a rare clinical entity with minimal literature available—to date, this injury has only been reported in a retrospective review of combat-related injuries in military personnel. It is important to maintain an understanding of knee extensor mechanism anatomy and perform thorough investigation of high-energy knee injuries to ensure adequate treatment of all injuries. The outcome presented in this case shows that positive results after complex extensor mechanism injuries may be achieved, but limited data exists to elucidate optimum treatment. It is essential for surgeons to have firm grasp of techniques used to treat each segment of the extensor mechanism so that they may be combined when a patient presents with complex, multifocal injury.