Repond: 100-200 words.
The foot is a part of the lower section of the body with a total of 28 bones, over a 100 ligaments, and multiple muscles and tendons which work together to keep the upper body stable and move the body around. (Foot care, 2015). There are special movements that are associated with the foot. Dorsiflexion is the opposite of plantar flexion; dorsiflexion is standing flat on your feet and pointing your toes upward to your face while plantar flexion is pointing your toes downward, for example, tiptoeing (Saladin, 2015). Inversion is the opposite of eversion; inversion is a foot movement where the sole of foot is turn inward to the body. While eversion the sole is turn outward, away from the body. Pronation and supination are opposite to each other and mainly associate with forearms movement. At times pronation is confused with inversion and also supination confused with eversion (Foot care, 2015). Pronation is a combination of dorsiflexion, eversion and abduction. Pronation can be observe in walking, when the heel make contact with the ground to disperse the pressure the foot rolled in ward to bear some of the impact. Supination is a combination of plantar flexion, inversion and abduction. Supination is an extreme outward movement of the foot and ankle when walking and the toes move and turn toward the other foot and the sole of the foot move in the same direction as well (Foot care, 2015). All these movement terminologies of the foot are also common with the forearms movement.
Extrinsic vs. intrinsic muscles
Muscles can be divided into two distinctive groups; intrinsic and extrinsic. Extrinsic and intrinsic muscles are located in places such as the tongue, larynx, back, hand and foot muscles. Intrinsic muscles are contained in a specific region and responsible for more fine motor skills (Saladin, 2015). There are ten intrinsic muscles in the plantar of foot that comes together to stabilize the arch of the foot and control the digits movement (Muscles of the foot, n.d.). Extrinsic muscles are group of muscles that lies outwardly on a structure, extrinsic muscles of the foot is responsible for eversion, inversion and plantar flexion and dorsiflexion of the foot (Muscles of the foot, n.d). Intrinsic muscles support extrinsic muscles in their actions.
Resources
Muscles of the foot (n.d.). Retrieved on May 17, 2016 from https://teachmeanatomy.info/lower-limb/muscles/foot/
North coast foot care (2015). Biomechanics. Retrieved on May 17, 2016 from https://www.northcoastfootcare.com/pages/Biomechanics.html
Saladin, K. S. (2015). Anatomy & Physiology: The unity of form and function. (7th Ed.). New York, NY: McGraw- Hill