Reading about scholasticism, medieval natural philosophy, liberal arts, it appears to me that, of all the Ancient Greece philosophers, only Aristotle was studied.
For instance, this passage (Blair 2006):
Rather than singling out the Renaissance as a time of decadent or eclectic Aristotelianism, recent scholarship has emphasized the vitality and variety of Aristotelian philosophy throughout the nearly 500 years of its dominance (c. 1200- 1690).
Why was Aristotle almost like the only Greek philosopher studied during the Middle Ages?
References:
Blair, Ann. "Natural Philosophy." In The Cambridge History of Science: Volume 3, Early Modern Science, edited by Katherine Park and Lorraine Daston, 365-405. Cambridge: Cambridge University Press, 2006.