Rare nonunion of tibial plateau fracture with patellar tendon rupture: A case report.

INTRODUCTION: Tibial plateau fractures (TPFs) are often complex, resulting from high-energy mechanisms of injury, such as being struck by a heavy object, falling from a height, or colliding with a motor vehicle. Due to the increasing geriatric population, TPFs have become more common, comprising approximately 8% of all fractures in patients aged > 65 years, and complex patterns are defined as Schatzker V and VI. Patellar tendon avulsion from the tibial tubercle is one of the most common and serious forms of extensor mechanism rupture; however, TPFs associated with rupture of the patellar tendon are extremely rare, with only one case being reported in the literature. TPF nonunion is relatively rare and has various causes, including age, injury severity, fracture classification, and the presence or absence of important diseases, such as anemia and hypoproteinemia. As observed, no case associated with patellar tendon rupture, and TPF nonunion has been reported previously. Herein, we report the first such case.

PATIENT CONCERNS: A 74-year-old man with no history of drug allergies, chronic diseases, or family diseases was injured in a car accident on August 3, 2021. The patient was referred to the emergency department for anterior knee pain, bleeding, chest pain, and abdominal pain that prevented him from standing and walking.

THERAPEUTIC PROCESS: The wound surface in the anterior knee was approximately 5 cm × 6 cm, which exhibited soft-tissue defects with bone exposure. Radiographs were obtained and showed a tibial plateau comminuted fracture, classified as Schatzker type V. Subsequently, postoperative radiography showed that the plateau articular surface had achieved good reduction, and the metallic anchor and hollow tension screws were rigidly fixed. Fracture reduction was observed, and the implant position was quite similar to previous radiographs. Computed tomography (CT) showed a small bony callus in the fracture area approximately 3 months after surgery. CT revealed delayed fracture healing, with some patients also having deformities approximately 12 months after surgery.

OUTCOMES: When reviewed after 2 years, the patient had no significantly pain and did not use walking aids. Knee function was preserved, with full extension and flexion to 90°. CT revealed TPF nonunion.