anatomy of the adult foot

 the foot consists of twenty-eight bones -about a quarter of all the bones in the hunman body are in both feet . the foot's bones are easiest to picture by looking down at the top of toot ,as in figure 1, drew by fromufoot company .  in this view ,you see the three sections of the foot ,the fore foot,the midfoot,and the hindfoot,the forefoot includes the toes,each of which have two or three phalanx bones (collectively they are phalanges) and the matatarsals ,the long bones attached to the toes ,the big toe (hallux vargus) have two phalanx bones and one interphalangeal joint ,and the other four toes each have three phalanx bones ,and two interphalangeal joints,the phalanx bones are named in sequence ,with the nearest to the foot called the proximal and distal ,the toes join to the metatarsals at the metatarsophalangeal joint ,which are at the ball of the foot ,below the head of the first metatarsal are two small bones called sesamoids.

figure 2   ,drew by from you foot = fromufoot company 

the midfoot have five tarsal nones of different shapes and sizes, this part of foot forms the foot's arch ,seen in the side ,view in figure2, and acts like stress,or shock, absorber,  the hind foot have two bones , the ankle boneand heel bones ,and three joints ,the ankle bone connects to the two long lowerleg bones by the ankle joint ,which is a hinge joint that gives the foot its ability to move up and down ,the heel bone the largest in the foot , connects to the ankle bone at the subtalar joint ,the third joint in the hindfoot is the midtarsal joint ,which actually consists of two joints , the calcaneocuboid ,which joins the calcaneus bone to the cuboid bone,and the talonavicular ,which joins the talus  boneto the navicular bone , this midtarsal joint allows are midfoot to turn inward relative to the hindfoot, the hindfoot's are seen in the side view in figure 2,and also in the view looking at the back of the heel in figure 3, drew by fromufoot .

the many joints in the foot and ankleprovide flexibility and allow motion whereever bones meet ,joints meet.joints consist of four types of tissue: cartilage capsule, ligament ,and tendon ,cartilage is a tough ,wear-resisitant tissue that covers the ends of bones in joints and provifes protection and cushioning for bones while the joint moves ,its smooth surface allows bonesto glide over one another with minimal friction ,most of us are familar with cartilage as the tissue that gives flexibility to our ears and nose ,although joint cartilage is a sepcialized type that is much harder than the cartilage found in the ears and nose .

capsule is  a soft tissue that forms a structure to encase and support joints,think of capsule tissue as a form-fitting envelop around a  joint .the envelope is lined with a menbrane that secrets a fluid to lubricate the joint and reduce friction ,ligaments are bundles of fibers that connect one bone to another ,hold tendons in place ,and help to stabilize  joints ,the longest ligament in the foot is pantar fascia ,which starts at the bottom of the heel and runs underneath  the foot  to insert  into the base of each toe ,.the plantar fascia contributes to the support ,stress absorption ,and stability of the foot's bones and joints tendons help a joint to move ,the largest and strongest tendon is the achills tendon , which connects the calf muscles to the back of heel ,when a person walks,the achilles tendon elevates the heel from the ground and contributes to the downward motion of the front of the foot ,this tendon's strength enables people to run ,jump ,and stand on tiptoes .other tendons in the foot include  the extensor tendons ,on the tops of the toes to pull the toes up  and the flexor tendons, on the bottoms of the toes to pull the toes down ,

the big toehas its own flexor and extensor tendons ,so it can move separatel ,while the four smaller toes share on muscle  with four extensor tendon slips,or branches off the main tendon ,when the muscle contracts, all four toes extend upward together .similarly ,these toes share a flexor muscle and tendon .the tibial tendons and peronea tendon play an important role in stabilizing the foot during walking ,the tibial tendons help to move the foot in ward  toward the midline of body ,while the peroneal tendon help to move the foot outward ,away from the midline of the body .

   muscles and tendon both give the its shape and enable it to move,. the foot's main muscles allow it to move up and doen  and in and out , help support the foot's arch .life and curl the toes ,and give the toes grip in the ground .

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