What is the Plantar Interossei?
The plantar interossei are small, deep muscles in the sole of your foot. They sit between the metatarsal bones, which are the long bones that run from your midfoot to your toes. Most people have three plantar interossei, associated with toes 3, 4, and 5. Each one starts from the side of a metatarsal and attaches into the base of its toe and into the tendon system that helps move the toe.