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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

what is physiology?
Grace Reply
Name three reasons to study anatomy and physiology
Hills Reply
Why do we need to study anatomy and physiology
Hills Reply
I want to study human anatomy
Ibrahim
What is anatomy
Christabel Reply
anatomy is the branch of medicine in which we study structure and part of the body
Ansar
The art of studying the different parts of any organized body, to discover their situation, structure, and economy; dissection.
ChristMas
anatomy is the study of structures that make up the body and how they re realated to each other
BRIAN
Anatomy is the study of structures of the body and shape of the body and body parts and their relationship to one another.
Abubakar
what is the importance of anatomy
Emeria Reply
cockroch ka sir katne ke bad o jinda kyu rahta
Anil
it helps us to understand the function of human metabolic system and also who these systems works which system play what role and so on
Nouman
systemic anatomy in short
Puja Reply
systemic circulation is the circulation in which heart supplies oxygenated blood to cells of body and takes deoxygenated blood away from body to heart
Ajeet
really?
Puja
yeah
BRIAN
ha ji
Ajeet
well much setisfy
Nouman
hello
Limpo
am new here
Limpo
ok
Emeria
am new here
Sindazi
I'm new as well
Crystal
who ask the question about cockroach cutting head
Nouman
the answer is They have an open circulatory system, which there's much less pressure in.After you cut their heads off very often their necks would seal off just by clotting," he adds. "There's no uncontrolled bleeding.The hardy vermin breathe through spiracles, or little holes in each body se
Nouman
does this platform helpful
Sindazi
well it's up-to you how you utilities this
Nouman
thnx ajeet
Puja
hello
AKARAJ
plz anatoy write note
AKARAJ
I think it is helpful
Alfred
Hi
Christabel
hi
Sachin
how do plateletes function in blood clotting
lydia
what are the function of the cell membrane
Elias Reply
the cell membrane helps in allowing and removing substances from the cell. it also aid in protecting the cell and giving it a definite shape.
veezy
The cell membrane is made up of a semipermeable lipid bi-layer which helps to regulate the kind of materials that enters it through active transport and passive diffusion.
Michael
properties of cardiac muscle
hotlan Reply
Myogenic,contain intercalated disc,control involuntary,fond in the heart walls only
AMOS
The exclusive characteristics of heart muscle is consists of Intercalated disc.
Doctor
Among the involuntary muscles only cardiac muscle is Myogenic but rest of involuntary muscles is Neurogenic.
Doctor
What about the exclusive characteristics of smooth muscle apart from lacking myofibrils in it's structure?
AMOS
What is the different between neurogenic and carcinogenic?
AMOS
distinguish between anatomy and physiology
Jonah Reply
Anatomy is the study of body parts and were they are found, physiology is the study of body parts and their functions
Alex
Anatomy is the scientific study of the body structure. While Physiology is the scientific study of the body function
Ossy
Anatomy is te scientic study of body parts and their physical relationship between different systems while physiology is te study of how all body systems works.
AMOS
1, molecules 2, cells 3, organ 4, tissue 5, organ systems 6l, organisms
hamisu Reply
hi
Musaffa
i m new here
Musaffa
hii
Coolx
hi
mushahid
how are you all
mushahid
Am fine bro and you
Nyier
Fine us all
AMOS
smallest part in anatomy
Mood Reply
functions of respiratory system
Dorice Reply
2. If the respiratory rate increases, carbon dioxide is removed from the blood, what effect would this have on blood hydrogen ion levels?
cris Reply
_____________are cells from fibrils and are active in the repair of tissue.
cris
a situations were by a muscle and skin get relation is called?
hamisu Reply
That is the relationship between intergumentary (Skin) and muscular system (muscles).
AMOS
what is exterior?
muslim Reply
outside of the organ cell etc
Amjad
means outside of something
Evania
What's outside!
ChristMas
the opposite of interior
Pinky
in interior out exterior
Hussain
you want to know about exterior
denis
Hope you are asking concerning relative anatomical terms of te body(exterior, posterior, Interior,medial,proximal and deep in te surfaces(interior) and lastly supervision.
AMOS

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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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