PMC5902117_01
PMC5902117_02
Plain radiographic anteroposterior view (a) and lateral view (b) of the left knee showing the absence of a patella and the presence of a small heterotopic calcification (white arrow) at the distal side of the quadriceps tendon.
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Plain radiographic examination did not show any fracture of the left knee but detected the absence of the patella and a small heterotopic calcification at the distal side of the quadriceps tendon (Figure 1).
Ultrasound examination showed a loose patellar tendon (within red circle) (a) compared with the contralateral side (b). The right is the cranial side, and the patella can be seen on the far right in (b).
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Ultrasound examination showed a loose left patellar tendon compared with the contralateral side (Figure 2), although it could not identify the rupture site.
T2-weighted magnetic resonance imaging showed a loose patellar tendon (red arrow) and subcutaneous edema (white arrow) (a) and tendon disruption (red arrow) (b) at the proximal side of the patellar tendon.
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Magnetic resonance imaging (MRI) revealed subcutaneous edema and tendon disruption at the proximal side of the left patellar tendon, which indicated patellar tendon rupture (Figure 3).
Intraoperative photographs. The top is cranial and the bottom is caudal. The patellar tendon and patellar retinaculum were completely ruptured. Hematoma filled the rupture site (a). We performed end-to-end suture with two Krackow locking stitches and figure-of-eight sutures (b).
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We made a midline incision instead of an oblique incision along the previous scar and found a complete patellar tendon rupture with both medial and lateral patellar retinaculum rupture with about a 2.0 cm gap filled with a hematoma (Figure 4(a)). We then performed end-to-end suturing with two Krackow locking stitches with #2 Hifi high-strength suture (CONMED, NY, USA) and added approximately twenty figure-of-eight sutures with #0 Hifi high-strength suture (Figure 4(b)).