The foot (plural: feet) is an anatomical
structure found in many vertebrates
. It is the terminal portion of a limb which bears weight and allows locomotion
. In many animals with feet, the foot is a separate organ at the terminal part of the leg
made up of one or more segments or bones, generally including claws or nails.
The word "foot", in the sense of meaning the "terminal part of the leg of a vertebrate animal" comes from "Old English fot "foot," from Proto-Germanic *fot (source also of Old Frisian fot, Old Saxon fot, Old Norse fotr, Danish fod, Swedish fot, Dutch voet, Old High German fuoz, German Fuß, Gothic fotus "foot"), from PIE
root *ped- "foot."
The "plural form feet is an instance of i-mutation."
thumb|Girl wearing anklet on her foot
The human foot is a strong and complex mechanical structure containing 26 bone
s, 33 joints
(20 of which are actively articulated), and more than a hundred muscle
s, and ligament
[Podiatry Channel, ''Anatomy of the foot and ankle'']
The joints of the foot are the ankle
and subtalar joint
and the interphalangeal articulations of the foot
. An anthropometric study of 1197 North American adult Caucasian males (mean age 35.5 years) found that a man's foot length was 26.3 cm with a standard deviation
of 1.2 cm.
The foot can be subdivided into the hindfoot, the midfoot, and the forefoot:
The ''hindfoot'' is composed of the talus
(or ankle bone) and the calcaneus
(or heel bone). The two long bones of the lower leg, the tibia
, are connected to the top of the talus to form the ankle
. Connected to the talus at the subtalar joint
, the calcaneus, the largest bone of the foot, is cushioned underneath by a layer of fat.
The five irregular bones of the ''midfoot'', the cuboid
, and three cuneiform
bones, form the arches of the foot
which serves as a shock absorber. The midfoot is connected to the hind- and fore-foot by muscles and the plantar fascia
The ''forefoot'' is composed of five toes and the corresponding five proximal long bones forming the metatarsus
. Similar to the fingers of the hand, the bones of the toes are called phalanges
and the big toe
has two phalanges while the other four toes have three phalanges each. The joints between the phalanges are called interphalangeal
and those between the metatarsus and phalanges are called metatarsophalangeal
Both the midfoot and forefoot constitute the ''dorsum'' (the area facing upwards while standing) and the ''planum'' (the area facing downwards while standing).
The ''instep'' is the arched part of the top of the foot between the toes and the ankle.
, and navicular
, and fifth metatarsal bone
There can be many sesamoid bone
s near the metatarsophalangeal joints, although they are only regularly present in the distal portion of the first metatarsal bone
[Platzer 2004, p. 220]
The human foot has two longitudinal
arches and a transverse arch maintained by the interlocking shapes of the foot bones, strong ligaments, and pulling muscles during activity. The slight mobility of these arches when weight is applied to and removed from the foot makes walking and running more economical in terms of energy. As can be examined in a footprint, the medial longitudinal arch curves above the ground. This arch stretches from the heel bone over the "keystone" ankle bone to the three medial metatarsals. In contrast, the lateral longitudinal arch is very low. With the cuboid serving as its keystone, it redistributes part of the weight to the calcaneus and the distal end of the fifth metatarsal. The two longitudinal arches serve as pillars for the transverse arch which run obliquely across the tarsometatarsal joints. Excessive strain on the tendons and ligaments of the feet can result in fallen arches or flat feet
[Mareb-Hoehn 2007, pp. 244–45]
The muscles acting on the foot can be classified into extrinsic muscles, those originating on the anterior or posterior aspect of the lower leg, and intrinsic muscles, originating on the dorsal (top) or plantar (base) aspects of the foot.
All muscles originating on the lower leg except the popliteus muscle
are attached to the bones of the foot. The tibia and fibula and the interosseous membrane separate these muscles into anterior and posterior groups, in their turn subdivided into subgroups and layers.
[Platzer 2004, p. 256]
= ''Anterior group''
''Extensor group'': the tibialis anterior
originates on the proximal half of the tibia and the interosseous membrane and is inserted near the tarsometatarsal joint
of the first digit. In the non-weight-bearing leg, the tibialis anterior dorsiflexes the foot and lift its medial edge (supination
). In the weight-bearing leg, it brings the leg towards the back of the foot, like in rapid walking. The extensor digitorum longus
arises on the lateral tibial condyle and along the fibula, and is inserted on the second to fifth digits and proximally on the fifth metatarsal. The extensor digitorum longus acts similar to the tibialis anterior except that it also dorsiflexes the digits. Extensor hallucis longus
originates medially on the fibula and is inserted on the first digit. It dorsiflexes the big toe and also acts on the ankle in the unstressed leg. In the weight-bearing, leg it acts similar to the tibialis anterior.
[Platzer 2004, p. 258]
''Peroneal group'': the peroneus longus
arises on the proximal aspect of the fibula and peroneus brevis
below it. Together, their tendons pass behind the lateral malleolus
. Distally, the peroneus longus crosses the plantar side of the foot to reach its insertion on the first tarsometatarsal joint, while the peroneus brevis reaches the proximal part of the fifth metatarsal. These two muscles are the strongest pronators and aid in plantar flexion. The peroneus longus also acts like a bowstring that braces the transverse arch of the foot.
[Platzer 2004, p. 260]
= ''Posterior group''
The ''superficial layer'' of posterior leg muscles is formed by the triceps surae
and the plantaris
. The triceps surae consists of the soleus
and the two heads of the gastrocnemius
. The heads of gastrocnemius arise on the femur
, proximal to the condyles, and the soleus arises on the proximal dorsal parts of the tibia and fibula. The tendons of these muscles merge to be inserted onto the calcaneus as the Achilles tendon
. The plantaris originates on the femur proximal to the lateral head of the gastrocnemius and its long tendon is embedded medially into the Achilles tendon. The triceps surae is the primary plantar flexor. Its strength becomes most obvious during ballet dancing. It is fully activated only with the knee extended, because the gastrocnemius is shortened during flexion of the knee. During walking it not only lifts the heel, but also flexes the knee, assisted by the plantaris.
[Platzer 2004, p. 262]
In the ''deep layer'' of posterior muscles, the tibialis posterior
arises proximally on the back of the interosseous membrane and adjoining bones, and divides into two parts in the sole of the foot to attach to the tarsus. In the non-weight-bearing leg, it produces plantar flexion and supination, and, in the weight-bearing leg, it proximates the heel to the calf. The flexor hallucis longus
arises on the back of the fibula on the lateral side, and its relatively thick muscle belly extends distally down to the flexor retinaculum
where it passes over to the medial side to stretch across the sole to the distal phalanx of the first digit. The popliteus
is also part of this group, but, with its oblique course across the back of the knee, does not act on the foot.
[Platzer 2004, p. 264]
On the top of the foot, the tendons of extensor digitorum brevis
and extensor hallucis brevis
lie deep in the system of long extrinsic extensor tendons. They both arise on the calcaneus and extend into the dorsal aponeurosis
of digits one to four, just beyond the penultimate joints. They act to dorsiflex the digits.
[Platzer 2004, p. 268]
Similar to the intrinsic muscles of the hand, there are three groups of muscles in the ''sole of foot'', those of the first and last digits, and a central group:
''Muscles of the big toe
'': the abductor hallucis
stretches medially along the border of the sole, from the calcaneus to the first digit. Below its tendon, the tendons of the long flexors pass through the tarsal canal
. The abductor hallucis
is an abductor and a weak flexor, and also helps maintain the arch of the foot. The flexor hallucis brevis
arises on the medial cuneiform bone and related ligaments and tendons. An important plantar flexor, it is crucial to ballet dancing. Both these muscles are inserted with two heads proximally and distally to the first metatarsophalangeal joint
. The adductor hallucis
is part of this group, though it originally formed a separate system (see contrahens
). It has two heads, the oblique head originating obliquely across the central part of the midfoot, and the transverse head originating near the metatarsophalangeal joints of digits five to three. Both heads are inserted into the lateral sesamoid bone
of the first digit. The adductor hallucis acts as a tensor of the plantar arches and also adducts the big toe and might plantar flex the proximal phalanx.
[Platzer 2004, pp. 270–72]
''Muscles of the little toe
'': Stretching laterally from the calcaneus to the proximal phalanx of the fifth digit, the abductor digiti minimi
form the lateral margin of the foot and are the largest of the muscles of the fifth digit. Arising from the base of the fifth metatarsal, the flexor digiti minimi
is inserted together with abductor on the first phalanx. Often absent, the opponens digiti minimi
originates near the cuboid bone and is inserted on the fifth metatarsal bone. These three muscles act to support the arch of the foot and to plantar flex the fifth digit.
[Platzer 2004, p. 272]
''Central muscle group'': The four lumbricals
arise on the medial side of the tendons of flexor digitorum longus
and are inserted on the medial margins of the proximal phalanges. The quadratus plantae
originates with two slips from the lateral and medial margins of the calcaneus and inserts into the lateral margin of the flexor digitorum tendon. It is also known as the flexor accessorius. The flexor digitorum brevis
arises inferiorly on the calcaneus and its three tendons are inserted into the middle phalanges of digits two to four (sometimes also the fifth digit). These tendons divide before their insertions and the tendons of flexor digitorum longus pass through these divisions. Flexor digitorum brevis flexes the middle phalanges. It is occasionally absent. Between the toes, the dorsal
and plantar interossei
stretch from the metatarsals to the proximal phalanges of digits two to five. The plantar interossei adduct and the dorsal interossei abduct these digits, and are also plantar flexors at the metatarsophalangeal joints.
[Platzer 2004, p. 274]
Due to their position and function, feet are exposed to a variety
of potential infection
s and injuries
, including athlete's foot
s, ingrown toenails
, Morton's neuroma
, plantar fasciitis
, plantar wart
s and stress fracture
s. In addition, there are several genetic disorder
s that can affect the shape and function of the feet, including a club foot
or flat feet
This leaves humans more vulnerable to medical problems that are caused by poor leg and foot alignments. Also, the wearing of shoes, sneakers and boots can impede proper alignment and movement within the ankle and foot. For example, High-heeled footwear
are known to throw off the natural weight balance
(this can also affect the lower back). For the sake of posture, flat soles with no heels are advised.
who specializes in the treatment of the feet practices podiatry
and is called a podiatrist. A pedorthist
specializes in the use and modification of footwear to treat problems related to the lower limbs.
s of the foot include:
– in which one or all of the metatarsal
s are displaced from the tarsus
– a fracture of the fifth metatarsal
– a fracture of the distal third of one of the metatarsals occurring because of recurrent stress
is the major cause of foot odor
. Sweat itself is odorless, but it creates a beneficial environment for certain bacteria to grow and produce bad-smelling substances.
In anatomy, pronation
is a rotational movement of the forearm (at the radioulnar joint) or foot (at the subtalar and talocalcaneonavicular joints). Pronation of the foot refers to how the body distributes weight as it cycles through the gait
. During the gait cycle the foot can pronate in many different ways based on rearfoot and forefoot function. Types of pronation include neutral pronation, underpronation (supination), and overpronation.
An individual who neutrally pronates initially strikes the ground on the lateral
side of the heel
. As the individual transfers weight from the heel to the metatarsus
, the foot will roll in a medial
direction, such that the weight is distributed evenly across the metatarsus. In this stage of the gait, the knee
will generally, but not always, track directly over the hallux
This rolling inwards motion as the foot progresses from heel to toe is the way that the body naturally absorbs shock. Neutral pronation is the most ideal, efficient type of gait when using a heel strike
gait; in a forefoot strike, the body absorbs shock instead via flexation of the foot.
As with a neutral pronator, an individual who overpronates initially strikes the ground on the lateral side of the heel. As the individual transfers weight from the heel to the metatarsus, however, the foot will roll too far in a medial direction, such that the weight is distributed unevenly across the metatarsus, with excessive weight borne on the hallux
. In this stage of the gait, the knee will generally, but not always, track inwards.
An overpronator does not absorb shock efficiently. Imagine someone jumping onto a diving board, but the board is so flimsy that when it is struck, it bends and allows the person to plunge straight down into the water instead of back into the air. Similarly, an overpronator's arches will collapse, or the ankles will roll inwards (or a combination of the two) as they cycle through the gait. An individual whose bone structure involves external rotation
at the hip
, knee, or ankle
will be more likely to overpronate than one whose bone structure has internal rotation
or central alignment. An individual who overpronates tends to wear down their running shoes on the medial (inside) side of the shoe towards the toe area.
When choosing a running or walking shoe, a person with overpronation can choose shoes that have good inside support—usually by strong material at the inside sole and arch of the shoe. It is usually visible. The inside support area is marked by strong greyish material to support the weight when a person lands on the outside foot and then roll onto the inside foot.
An individual who underpronates also initially strikes the ground on the lateral side of the heel. As the individual transfers weight from the heel to the metatarsus, the foot will not roll far enough in a medial direction. The weight is distributed unevenly across the metatarsus, with excessive weight borne on the fifth metatarsal
, towards the lateral side of the foot. In this stage of the gait, the knee will generally, but not always, track laterally of the hallux
Like an overpronator, an underpronator does not absorb shock efficiently – but for the opposite reason. The underpronated foot is like a diving board that, instead of failing to spring someone in the air because it is too flimsy, fails to do so because it is too rigid. There is virtually no give. An underpronator's arches or ankles don't experience much motion as they cycle through the gait. An individual whose bone structure involves internal rotation
at the hip, knee, or ankle will be more likely to underpronate than one whose bone structure has external rotation or central alignment. Usually – but not always – those who are bow-legged
tend to underpronate. An individual who underpronates tends to wear down their running shoes on the lateral (outside) side of the shoe towards the rear of the shoe in the heel area.
Society and culture
Humans usually wear shoe
s or similar footwear for protection from hazards when walking outside. There are a number of contexts where it is considered inappropriate to wear shoes. Some people consider it rude to wear shoes into a house and a Māori Marae
should only be entered with bare feet.
is the most common form of sexual fetish.
is the soft foot of a mammal, generally a quadruped, that has claws or nails (e.g., a cat or dog's paw). A hard foot is called a hoof
. Depending on style of locomotion, animals can be classified as plantigrade
(sole walking), digitigrade
(toe walking), or unguligrade
The metatarsals are the bones that make up the main part of the foot in humans, and part of the leg in large animals or paw in smaller animals. The number of metatarsals are directly related to the mode of locomotion with many larger animals having their digits reduced to two (elk
) or one (horse
). The metatarsal bones of feet and paws are tightly grouped compared to, most notably, the human hand where the thumb metacarpal diverges from the rest of the metacarpus.
[France 2008, p. 537]
Metaphorical and cultural usage
The word "foot" is used to refer to a "...linear measure was in Old English (the exact length has varied over time), this being considered the length of a man's foot; a unit of measure used widely and anciently. In this sense the plural is often foot. The current inch and foot are implied from measurements in 12c."
The word "foot" also has a musical meaning; a "...metrical foot (late Old English, translating Latin pes, Greek pous in the same sense) is commonly taken to represent one rise and one fall of a foot: keeping time according to some, dancing according to others."
The word "foot" was used in Middle English to mean "a person" (c. 1200).
The expression "...to put one's best foot foremost first recorded 1849 (Shakespeare has the better foot before, 1596)".
The expression to "...put one's foot in (one's) mouth "say something stupid" was first used in 1942.
The expression "put (one's) foot in something" meaning to "make a mess of it" was used in 1823.
The word "footloose" was first used in the 1690s, meaning "free to move the feet, unshackled"; the more "figurative sense of "free to act as one pleases" was first used in 1873.
Like "footloose", "flat-footed" at first had its obvious literal meaning (in 1600, it meant "with flat feet") but by 1912 it meant "unprepared" (U.S. baseball slang).
* Flat feet
* Foot binding
* Foot fetishism
* Foot gymnastics
* Foot pressure
* Foot washing
* Gait analysis
* Pes cavus
* Sole (foot)
* Runner's toe
, repetitive injury seen in runners
* Ball (anatomy)
* Squatting position
*Comparison of orthotics