Nicole Kelley's essay "Deformity and Disability in Greece and Rome," which is part of the edited volume This Abled Body: Rethinking Disabilities and Biblical Studies, offers an interesting and brief engagement with disabilities and deformities in classical antiquity. She opens by drawing attention to some of the methodological and definitional problems in trying to understand the historical reality of disabled and deformed persons in the ancient world. Despite the probability that disability and deformity were very common, the evidence is relatively sparse, and portrayals in art and literature may not always reflect social reality. The ancients also lacked clearly defined categories like "disabled" or "deformed." Kelley spends the rest of her essay focusing on two figures from Greek mythology: the god Hephaestus, who is often portrayed as congenitally lame, and Teiresias, the blind prophet.
In her discussion of Hephaestus she gives attention to other sources that address congenital disabilities and deformities, including evidence that idealizes the exposure or elimination of infants who are deemed unfit. Whether or not these texts reflect actual practice remains an open question. She also discusses the role of deformed people in entertainment, mentioning, among other things, the evidence that deformed persons were kept as pets in the Roman world and sold in "monster markets." Kelley's treatment of Hephaestus closes by mentioning the economic prospects of disabled persons, noting that there is evidence that their economic outlook "was not necessarily bleak or characterized by utter dependence on family and friends" (41).
Kelley's treatment of Teiresias explores the prevalence of references to seeing impairment in the ancient evidence, the idea that blindness can be a punishment from the gods, sometimes as a result of viewing sacred persons or spaces. Portrayals of the blind sometimes include compensatory powers, such as Teiresias' ability to prophesy.
Kelley's article is worth checking out as a short and nicely balanced introduction to some of the issues and sources for exploring disability in classical antiquity. The entire essay can currently be accessed on Google Books.
If you are interested in researching this area further, here are some of the primary and secondary sources she cites in the essay:
Edwards, Martha Lynn. "Physical Disability in the Ancient Greek World." (Dissertation)
Garland, Robert. The Eye of the Beholder: Deformity and Disability in the Graeco-Roman World.
Rose, Martha L. The Staff of Oedipus: Transforming Disability in Ancient Greece.
Homeric Hymn to Pythian Apollo 316-18
Plato, Republic 460c
Aristotle, Politics 1335b
Soranus, Gynecology 2.10
Plutarch, Lycurgus 16.1
Dionysius Halicarnassus 2.15
Cicero, Laws 3.19
Suetonius, Claudius 3.2
Cicero, On Oratory 2.239
Alciphron, Letters of Farmers 24.1
Plutarch Mor. 234e, 241e, 331b
Dio Chrysostom, Or. 36.10-11