Avulsion fracture of the tibial tuberosity is an uncommon lesion generally seen in adolescents. Intra-articular lesions combined with a tibiaal tuberosity fracture reported in the literature are; 3 patellar tendon ruptures, 2 anterior cruciate ligament tears, 2 medial collateral ligament tears, 2 medial meniscus tears, one arcuate ligament tear, and one lateral meniscus tear. In our study, both cases sustained an avulsion fracture of the tibial tuberosity. Preoperative MRI in one case revealed posterior cruciate ligament rupture. Under the image intensifier, we treated both patients by closed reduction and percutaneous screwing with 2 cancellous screws. Radiographic assessment showed complete healing of the avulsion fractures in both cases. Both of our patients gained previous levels of daily and sporting activity prior to the injury, and were completely asymptomatic. Our objective in reporting this case study is to point to the fact that there is no previous reporting of the avulsion fracture of the tibial tuberosity accompanied by posterior cruciate ligament rupture in the literature and to evaluate the findings of the minimal invasive treatment method we applied to both cases.