
“In man it’s sural part is vestigial and like it’s homologue, the Palmaris, is variable and sometimes absent…”
Grant’s Method of Anatomy, 9th Edition
Plantaris is a small spindle shaped muscle which runs from the outside of the knee, crossing to between the calf muscles to lie on and then merge with the inner aspect of the Achilles tendon. The muscle has a small body, which is narrow in width and unusually long, leading to a vulnerability to injury. The muscle contributes less than 1% of flexion power in the lower limb, but has a much greater role in proprioception, giving the body feedback on where the limb is in space. The plantaris may seem more problematic than useful, but for tree climbing primates it functions to grasp objects with the feet. It’s main function in human males is to interrupt a perfectly good match of tennis. #atleastwewon #letsmakelemonade