Muscle · Foot

Interossei of the foot

Musculi interossei pedis

The small muscles packed into the spaces between the long bones of the foot. There are two sets: four on top that spread the toes apart, and three underneath that pull them together. Spreading and squeezing the toes sounds trivial, but that is not the point of them — they are the foot's fine-tuners. They stabilise the toes at the knuckles so the foot can push off through a stable platform, and they are constantly making tiny adjustments to keep you balanced when you stand on one leg. When they stop contributing, balance gets worse and the long toe extensors take over, which is what claw toes look like.