Surgical treatment of Popliteal Artery Aneurysm (PAA), either medial or posterior approach, remains controversial. Debate continues regarding which approach has the less morbidity and the better long patency. A single center retrospective study in our department was done comparing the primary patency between the two different approaches. Both approaches have relatively the same primary patency. Concerning the bypass material, vein bypass stays patent for a longer period of time. By adding the preoperative run-off situations as a variable to compare the two approaches, the posterior approach using the vein as a bypass material has more competitive results. With a poor run-off situation, the prognosis is not promising.