Simultaneous Bilateral Patellar Tendon Ruptures Treated with Primary Repair and Dermal Allograft Augmentation: A Case Report

Abstract

Introduction: Patellar tendon ruptures are a relatively common injury encountered by orthopedic surgeons and typically only occur unilaterally. However, there are rare reports of bilateral patellar tendon ruptures occurring simultaneously, in patients with underlying systemic disorders, higher energy mechanisms, or injury or overuse in high-level athletes. When patellar tendon ruptures occur, and the extensor mechanism is disrupted, patellar tendon repair versus reconstruction is warranted to restore functionality. The use of dermal allografts for the reconstruction of chronic patellar tendon ruptures is well described; however, there is not much literature describing their use in the acute setting. This report describes the primary repair of simultaneous bilateral patellar tendon rupture with the use of the ArthroFLEX Decellularized Dermal Allograft. This is a novel use for this allograft, as it is currently indicated for use in the treatment of various tendon repairs/reconstructions as well as hallux rigidus and hip capsule reconstruction. There are no reports describing the use of the ArthroFLEX Decellularized Dermal Allograft in the acute setting as augmentation of primary patellar tendon repair in a patient with simultaneous bilateral patellar tendon ruptures in the absence of underlying systemic disease; thus, this report presents a novel use for this dermal allograft.

Case report: This patient is a 40-year-old African American male with no active underlying systemic diagnosis who sustained simultaneous bilateral patellar tendon ruptures from a low-energy mechanism. He subsequently underwent bilateral patellar tendon repair during which a dermal allograft augment was utilized to further strengthen this repair. In addition, a defunctioning purse string suture was used to further protect the patellar tendon repair by off loading the extensor mechanism.

Conclusion: This report adds to the body of literature surrounding the rare entity of simultaneous bilateral patellar tendon ruptures in otherwise healthy patients while also presenting a novel use for the ArthroFLEX Decellularized Dermal Allograft in the acute repair of a patellar tendon rupture. This report also supports the use of a defunctioning purse string suture to help offload the healing extensor and decrease the amount of tension across a healing tendon repair.

Keywords: ArthroFLEX decellularized dermal allograft; Simultaneous bilateral patellar tendon ruptures; dermal allograft augmentation; primary patellar tendon repair.

Figure 1

Preoperative lateral X-ray of the right knee showing patella alta and increased Insall-Salvati ratio.

Figure 2

Preoperative lateral X-ray of the left knee showing patella alta and increased Insall-Salvati ratio.

Figure 3

Intraoperative photo of the left knee showing the primary patellar tendon repair with dermal allograft augment sutured to the inferior portion of the tendon with #2 FiberWire.

Figure 4

Intraoperative photo of the left knee showing allograft augment sutured in place over the patellar tendon repair, using #2 FiberWire with tails of native patellar tendon superiorly.

Figure 5

Intraoperative photo of the left knee showing tails of native patellar tendon sewn over the medial and lateral aspects of the allograft augment using 2-0 FiberWire.

Figure 6

Intraoperative photo of the left knee showing allograft augment in place with 2-0 FiberWire purse string suture in place. Purse string suture was passed through a drill hole in the tibial tubercle, around either side of the patellar tendon and around the quadriceps tendon.

Figure 7

Postoperative lateral X-ray of the right knee showing restored patellar alignment.

Figure 8

Postoperative lateral X-ray of the left knee showing restored patellar alignment.