Medial collateral sesamoid ligament

In carnivores, the lateral and medial collateral sesamoidean ligaments are short, flat bands on each side of the metacarpophalangeal joint, each subdivided in two parts, one connecting the lateral (or medial) surface of the sesamoid to the distal surface of the metacarpal bones palmar to the proximal attachments of the collateral ligaments of the metacarpophalangeal joint, and the second part, connecting the lateral (or medial) surface of the sesamoid to the lateral (or medial) tubercle of the base of the proximal phalanx.

In horses, the medial and lateral collateral sesamoid ligaments are attached proximal to the depressions on each side of the distal end of the first phalanx, run palmarodistally and insert on the lateral angle of the distal sesamoid bone (navicular bone), coffin bone and ungual cartilages.