Talar injuries represent serious medico-surgical conditions because of the involvement of the talus in multiple articulations, such as the subtalar, the transverse talar, and the ankle joint complex. Its complete detachment from the surrounding ligaments and bone is known as talar extrusion, a very rare injury with a complicated treatment course. We report a case of a 43-year-old female patient presenting with a non-retrieved complete left talar body extrusion associated with a floating knee, manifested by left tibial shaft fracture and left supracondylar femoral fracture. The patient was treated with open reduction and internal fixation for the floating knee and a manually shaped talar cement spacer with staged tibiocalcaneal arthrodesis for the ankle. The patient was monitored over a six-year period. This case is reported for the extreme rarity of lost open talar body extrusion, and its problematic treatment in the absence of clear guidelines, especially with the presence of multiple concomitant ipsilateral fractures of the limb, such as floating knee, as in this case.