Boyd and Knight classification of talar body fractures

Boyd and Knight classification of fractures of the body of talus divides them into two basic groups that can be further divided according to displacement.

Type Description
Type I - Coronal or sagittal shear fracture
Type Ia undisplaced
Type Ib displacement at ankle joint
Type Ic displacement at ankle and subtalar joint
Type Id total displacement
Type II - Horizontal shear fracture
Type IIa undisplaced
Type IIb displaced

References:

1. Boyd HB, Knight RA. Fractures of the astragalus. South Med J. 1942;35:160–167.
2.
Ebraheim NA, Patil V, Owens C, Kandimalla Y. Clinical outcome of fractures of the talar body. Int Orthop. 2008 Dec;32(6):773–7.