The Collaborative International Dictionary of English v.0.48:

Fettered \Fet"tered\, a. (Zool.)
   Seeming as if fettered, as the feet of certain animals which
   bend backward, and appear unfit for walking.
   [1913 Webster]

WordNet (r) 3.0 (2006):

fettered
    adj 1: bound by chains fastened around the ankles [syn:
           fettered, shackled]