The Collaborative International Dictionary of English v.0.48:

Hunchbacked \Hunch"backed`\, a.
   Having a humped back.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hunchbacked
    adj 1: characteristic of or suffering from kyphosis, an
           abnormality of the vertebral column [syn: crookback,
           crookbacked, humped, humpbacked, hunchbacked,
           gibbous, kyphotic]