Simultaneous Bilateral Quadriceps Tendon Rupture After Low-Energy Trauma in a 73-Year-Old Man: A Case Report and Literature Review

Simultaneous bilateral quadriceps tendon rupture is an exceptionally rare injury of the knee extensor mechanism and may present a diagnostic challenge, particularly after low-energy trauma. Prompt recognition is essential to restore knee extension and ambulatory function.

We report the case of a 73-year-old man who presented to the Emergency Department after falling while descending stairs and landing directly onto both knees. He developed immediate bilateral knee pain and inability to ambulate. Clinical examination revealed palpable suprapatellar defects bilaterally, inability to perform straight leg raise, and loss of active knee extension in both knees. Plain radiographs demonstrated bilateral patella baja with central calcific densities suggestive of pre-existing degenerative tendon changes. Based on the evident clinical findings, no further magnetic resonance imaging was required.

The patient underwent urgent bilateral surgical repair using a transosseous patellar tunnel technique with No. 5 nonabsorbable Ethibond sutures in a locking Krackow configuration. A structured postoperative rehabilitation program with progressive mobilization and strengthening was implemented.

At 18-month follow-up, the patient reported no pain, independent ambulation without assistive devices, unrestricted activities of daily living, full knee extension, and flexion to approximately 130° bilaterally.

This case highlights that simultaneous bilateral quadriceps tendon rupture may occur even in the absence of major systemic comorbidity and should be considered in elderly patients presenting with acute bilateral knee pain and extensor mechanism dysfunction after minor trauma. Early surgical repair combined with structured rehabilitation can result in excellent functional recovery.