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Evaluation of Stem Cell Therapies in a Bilateral Patellar Tendon Injury Model in Rats
Published on: March 30, 2018
Staged Non-simultaneous Bilateral Patellar Tendon Rupture Treated With Direct Repair and Suture Tape Augmentation
Yuko Yagi1, Hironori Kojima1,2, Aiichiro Yamamoto1
1Orthopedics, Otakanomori Hospital, Kashiwa, JPN.
None:
Bilateral patellar tendon rupture is an exceedingly rare injury, with most reported cases involving simultaneous ruptures in patients with predisposing systemic diseases or medication use. This report describes a unique case of a staged, non-simultaneous bilateral patellar tendon rupture that was surgically managed. A 47-year-old man with class I obesity (body mass index, 33 kg/m2) and undiagnosed diabetes mellitus, and a history of long-term basketball participation, sustained a right patellar tendon rupture after a workplace accident. The injury went unrecognized, and two weeks later, a second low-energy fall led to a rupture of the left patellar tendon. Physical examination revealed bilateral patella alta, and radiographs confirmed the diagnosis, with marked calcification noted in the right tendon consistent with chronic changes. The patient underwent a successful direct repair of both patellar tendons, augmented with a suture tape. While both knees achieved favorable functional recovery at the nine-month follow-up, the subacute right knee showed slightly reduced range of motion and residual stiffness compared to the acute left knee. This case highlights that staged bilateral ruptures can occur in patients with metabolic and mechanical risk factors. The slightly reduced function on the subacute side suggests that surgical repair performed within two weeks may yield more favorable outcomes than a delayed repair.
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