Presentation
Knee pain post fall. Total knee replacement one month ago.
Patient Data
Joint effusion and prepatellar soft tissue swelling. Lateral patellar tilt and the patella is low-lying. Tibiofemoral components are appropriately positioned. No periprosthetic lucency.
Total knee replacement with patellar resurfacing. No periprosthetic lucency. Small joint effusion. Skin staples.
Complete rupture of the quadriceps tendon just proximal to the patellar attachment with hematoma and fluid filling the defect gap.
Patellar tendinosis with no demonstrable patellar tendon tear.
Moderate degree of knee joint effusion. Total knee replacement is observed.
Minimal edema noted around the tibial plate in the proximal tibia without any demonstrable fracture. Minimal edema noted in the medial femoral condyle deep to the femoral plate. Mild degree of edema along the fibular head with unremarkable appearance of the superior tibiofibular joint.
Courtesy of Dr Manish Mittal.
Case Discussion
Quadriceps rupture post total knee replacement is a rare complication (0.1% incidence). When comparing the two x-rays, the alignment of the patellar is easily seen to have changed from the immediate post-operative x-ray. Clinical suspicion for a quadriceps tendon was high and after the MRI the patient proceeded to surgical repair.