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Phalanges

The toes contain a total of 14 phalanx bones (phalanges), arranged in a similar manner as the phalanges of the fingers (see [link] ). The toes are numbered 1–5, starting with the big toe ( hallux    ). The big toe has two phalanx bones, the proximal and distal phalanges. The remaining toes all have proximal, middle, and distal phalanges. A joint between adjacent phalanx bones is called an interphalangeal joint.

View this link to learn about a bunion, a localized swelling on the medial side of the foot, next to the first metatarsophalangeal joint, at the base of the big toe. What is a bunion and what type of shoe is most likely to cause this to develop?

Arches of the foot

When the foot comes into contact with the ground during walking, running, or jumping activities, the impact of the body weight puts a tremendous amount of pressure and force on the foot. During running, the force applied to each foot as it contacts the ground can be up to 2.5 times your body weight. The bones, joints, ligaments, and muscles of the foot absorb this force, thus greatly reducing the amount of shock that is passed superiorly into the lower limb and body. The arches of the foot play an important role in this shock-absorbing ability. When weight is applied to the foot, these arches will flatten somewhat, thus absorbing energy. When the weight is removed, the arch rebounds, giving “spring” to the step. The arches also serve to distribute body weight side to side and to either end of the foot.

The foot has a transverse arch, a medial longitudinal arch, and a lateral longitudinal arch (see [link] ). The transverse arch forms the medial-lateral curvature of the mid-foot. It is formed by the wedge shapes of the cuneiform bones and bases (proximal ends) of the first to fourth metatarsal bones. This arch helps to distribute body weight from side to side within the foot, thus allowing the foot to accommodate uneven terrain.

The longitudinal arches run down the length of the foot. The lateral longitudinal arch is relatively flat, whereas the medial longitudinal arch is larger (taller). The longitudinal arches are formed by the tarsal bones posteriorly and the metatarsal bones anteriorly. These arches are supported at either end, where they contact the ground. Posteriorly, this support is provided by the calcaneus bone and anteriorly by the heads (distal ends) of the metatarsal bones. The talus bone, which receives the weight of the body, is located at the top of the longitudinal arches. Body weight is then conveyed from the talus to the ground by the anterior and posterior ends of these arches. Strong ligaments unite the adjacent foot bones to prevent disruption of the arches during weight bearing. On the bottom of the foot, additional ligaments tie together the anterior and posterior ends of the arches. These ligaments have elasticity, which allows them to stretch somewhat during weight bearing, thus allowing the longitudinal arches to spread. The stretching of these ligaments stores energy within the foot, rather than passing these forces into the leg. Contraction of the foot muscles also plays an important role in this energy absorption. When the weight is removed, the elastic ligaments recoil and pull the ends of the arches closer together. This recovery of the arches releases the stored energy and improves the energy efficiency of walking.

Questions & Answers

where is heart located
medical Reply
thoracic cavity
Ashley
1
Noor
between which line
medical
where is the thorax located at?
angel
heart located between T5-T8
Biplav
thorax is the area between the base of neck to the diaphragm
Biplav
The heart is placed Obliquely behind the body of the sternum and adjoining part of the costal cartilages, so that 1/3 of its lies to the right and 2/3 to the left of the median plane
Manisha
The heart lies in the thoracic cavity in the mediastinum (the space between the lungs) . It lies obliquely, a little more to the left than the right. Presents the base above and the apex below. The apex is 9cm to the left of the midline at the level of the 5th intercostal space
Bashraba
why does a person's complexion change when he relocates to another cold environment & tends to become more light skinned, does this mean the distribution of melanin to the surface of the skin changes ?
Ferrel Reply
what is Aponeurosis
Komolika Reply
aponerosis is modifications of deep fascia of the skin.. it generally covers the muscles Or tendons within it
niyati
A sheet of parly white fibrous tissue that takes the place of tendon in flat muscles having a wide area of attachment
mishra
what is the difference between sex and gender?
Hridya Reply
Those are synonyms
Ferrel
What is Physiology?
Nancy Reply
The study of functions of the human body.
Evans
study of human body
obaidullah
The biochemical study of any organism (eg. different systems) is called Physiology.
Doctor
which category of bone is among the most numerous in the skeleton?
DAMSON Reply
what is a nutrition ?
Jitu Reply
Nutrition is the process of providing or obtaining the food necessary for health and growth.
Gloria
Nutrition is the process of taking food and using it for growth , repair and metabolism ...
Om
how many parts of bone
Amir Reply
know the meaning of both messages
Amir
what is the name of suture that is present between frontal. parietal. occipetal ...
Amir
what is the name of suture that is present between frontal. parietal. occipetal ...
Amir
Coronal suture present between frontal and parietal bone and lambdoid suture present between parietal and occipital bone ...
Om
Squamous suture
Ferrel
& where is the squamous suture ?
Ferrel
what is meant by synovial joint? and what is this role
Fozia
type of joint that is found between bones that move against each other. it's function is to prevent bone friction
Ferrel
epinephrine is the true meaning of epi
Michele Reply
what does the word 'epi' means
Melex Reply
good evening, my question is what are function of metal in human body like aluminum?
Yosef Reply
please want you to help me in understanding digestive system
Hamidu Reply
this is muscular system?
Patel Reply
bruh moment
Viana
It is an organ system consisting of skeletal ,smooth and cardiac muscles
mishra
im too retarded to be here
Viana
naww Viana, I know it's hard to absorb info, I'm having the same issue, but keep practising, chin up.
Katarina
what is the question
Amir
to have a better understanding as to how our human bodies function. the knowledge we gain can improve our quality of life. Without our study of anatomy how could a doctor know what prescription to give us when our bodies is being attacked by a bacteria? We wouldn't!
Robin Reply
discuss nervers system in human being life.
Allen Reply
neuralgia what is other name of it
Muniba

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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