Overview
In the cat the metatarsus (ossa metatarsalia) is made of four functional metatarsal bones, II to V, and a vestigial metatarsal I, a small bony remnant on the medial side. That is why the cat usually has no dewclaw on the pelvic limb. The metatarsals are longer than the metacarpals and, in the digitigrade stance, are held nearly vertical.
Key features
- Metatarsals III and IV: the longest and most central; they bear most of the load.
- Metatarsals II and V: slightly shorter, on either side.
- Base: articulates with the distal tarsal bones.
- Head: articulates with the proximal phalanx; two proximal sesamoid bones per digit lie on its plantar side.
- Metatarsal pad: a single three-lobed pad, plantar to the metatarsophalangeal joints.
Clinical relevance
- Scottish Fold osteochondrodysplasia: short, thickened metatarsals with plantar exostoses that fuse the bones and limit movement.
- Metatarsal fractures: after trauma and crushing injuries.
- Plantigrade stance: in diabetic neuropathy the whole metatarsus rests on the ground.
- Polydactyly: can also affect the hind paw, with extra digits and metatarsals on the medial side.