The =fibula= of the horse is a much reduced long bone, situated along
the outer side of the tibia.
The =shaft= or =body= (Corpus fibulæ) is a slender rod which forms the
outer boundary of the interosseous space; it usually terminates below in
a pointed end about one-half to two-thirds of the way down the external
border of the tibia.
The =proximal extremity= or =head= (Capitulum fibulæ) is relatively
large, and is flattened transversely. Its internal surface presents a
narrow area along the upper border for articulation with the tibia. The
external surface is rough and gives attachment to the external lateral
ligament of the stifle joint. It has rounded anterior and posterior
borders.
[Illustration: