Source : Webster's Revised Unabridged Dictionary (1913)

Osteoclasis \Os`te*o*cla"sis\, n. [NL. See {Osteoclast}.]
   (Surg.)
   The operation of breaking a bone in order to correct
   deformity.

Source : WordNet®

osteoclasis
     n : treatment of a skeletal deformity by intentionally
         fracturing a bone