This is a simple joint, of limited action, and formed by the union of the lower extremity of the os suffraginis with the upper extremity of the small pastern. The ligaments which unite these bones together are a capsular ligament, two strong short lateral ligaments, some of the fibres of which descend and ultimately become connected with the extremities of the navicular bone, and two short posterior ligaments (fig. 357).

Its movements are those of flexion and extension.