In humans and many other primates, the calcaneus (; from the Latin ''calcaneus'' or ''calcaneum'', meaning heel) or heel bone is a
bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...
of the
tarsus of the
foot
The foot ( : 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 ...
which constitutes the
heel
The heel is the prominence at the posterior end of the foot. It is based on the projection of one bone, the calcaneus or heel bone, behind the articulation of the bones of the lower Human leg, leg.
Structure
To distribute the compressive for ...
. In some other animals, it is the point of the
hock
Hock may refer to:
Common meanings:
* Hock (wine), a type of wine
* Hock (anatomy), part of an animal's leg
* To leave an item with a pawnbroker
People:
* Hock (surname)
* Richard "Hock" Walsh (1948-1999), Canadian blues singer
Other uses:
* A t ...
.
Structure
In humans, the calcaneus is the largest of the
tarsal bone
In the human body, the tarsus is a cluster of seven articulating bones in each foot situated between the lower end of the tibia and the fibula of the lower leg and the metatarsus. It is made up of the midfoot (cuboid, medial, intermediate, and la ...
s and the largest bone of the foot. Its long axis is pointed forwards and laterally.
The
talus bone
The talus (; Latin for ankle or ankle bone), talus bone, astragalus (), or ankle bone is one of the group of foot bones known as the tarsus. The tarsus forms the lower part of the ankle joint. It transmits the entire weight of the body from the ...
, calcaneus, and
navicular bone
The navicular bone is a small bone found in the feet of most mammals.
Human anatomy
The navicular bone in humans is one of the tarsal bones, found in the foot. Its name derives from the human bone's resemblance to a small boat, caused by the ...
are considered the proximal row of tarsal bones.
In the calcaneus, several important structures can be distinguished:
[Platzer (2004), p 216]
There is a large calcaneal tuberosity located posteriorly on plantar surface with medial and lateral tubercles on its surface. Besides, there is another peroneal tubecle on its lateral surface.
On its lower edge on either side are its lateral and medial processes (serving as the origins of the
abductor hallucis
The abductor hallucis muscle is an intrinsic muscle of the foot. It participates in the abduction and flexion of the great toe.
Structure
The abductor hallucis muscle is located in the medial border of the foot and contributes to form the prom ...
and
abductor digiti minimi). The
Achilles tendon
The Achilles tendon or heel cord, also known as the calcaneal tendon, is a tendon at the back of the lower leg, and is the thickest in the human body. It serves to attach the plantaris, gastrocnemius (calf) and soleus muscles to the calcaneus (h ...
is inserted into a roughened area on its superior side and the
cuboid bone
In the human body, the cuboid bone is one of the seven tarsal bones of the foot.
Structure
The cuboid bone is the most lateral of the bones in the distal row of the tarsus. It is roughly cubical in shape, and presents a prominence in its inf ...
articulates with its anterior side. On its superior side there are three articular surfaces for the articulation with the
talus bone
The talus (; Latin for ankle or ankle bone), talus bone, astragalus (), or ankle bone is one of the group of foot bones known as the tarsus. The tarsus forms the lower part of the ankle joint. It transmits the entire weight of the body from the ...
.
Between these superior articulations and the equivalents on the talus is the tarsal sinus (a canal occupied by the
interosseous talocalcaneal ligament
The interosseous talocalcaneal ligament forms the chief bond of union between the talus and calcaneus.
It is a portion of the united capsules of the talocalcaneonavicular and the talocalcaneal joints, and consists of two partially united layers ...
). At the upper and forepart of the medial surface of the calcaneus, below the middle talar facet, there is a horizontal eminence, the talar shelf (also sustentaculum tali).
Sustentaculum tali gives attachment to the
plantar calcaneonavicular (spring) ligament, tibiocalcaneal ligament, and medial talocalcaneal ligament. This eminence is concave above, and articulates with the middle calcaneal articular surface of the
talus; below, it is grooved for the tendon of the
flexor hallucis longus
The flexor hallucis longus muscle (FHL) is one of the three deep muscles of the posterior compartment of the leg that attaches to the plantar surface of the distal phalanx of the great toe. The other deep muscles are the flexor digitorum longus an ...
; its anterior margin gives attachment to the plantar calcaneonavicular ligament, and its medial margin to a part of the
deltoid ligament
The deltoid ligament (or medial ligament of talocrural joint) is a strong, flat, triangular band, attached, above, to the apex and anterior and posterior borders of the medial malleolus.
The deltoid ligament is composed of 4 fibers:
1. Anterior ti ...
of the
ankle-joint
The ankle, or the talocrural region, or the jumping bone (informal) is the area where the foot and the leg meet. The ankle includes three joints: the ankle joint proper or talocrural joint, the subtalar joint, and the inferior tibiofibular joint ...
.
On the lateral side is commonly a tubercle called the calcaneal tubercle (or trochlear process). This is a raised projection located between the tendons of the
peroneus longus
In human anatomy, the fibularis longus (also known as peroneus longus) is a superficial muscle in the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body ( eversion) and to extend the foot downwar ...
and
brevis. It separates the two oblique grooves of the lateral surface of the calcaneus (for the tendons of the peroneal muscles).
Its chief anatomical significance is as a point of divergence of the previously common pathway shared by the distal tendons of peroneus longus and peroneus brevis ''en route'' to their distinct respective attachment sites.
The calcaneus is part of two joints: the proximal intertarsal joint and the
talocalcaneal joint
In human anatomy, the subtalar joint, also known as the
talocalcaneal joint, is a joint of the foot. It occurs at the meeting point of the talus and the calcaneus.
The joint is classed structurally as a synovial joint, and functionally as a p ...
. The point of the calcaneus is covered by the calcanean
bursa
( grc-gre, Προῦσα, Proûsa, Latin: Prusa, ota, بورسه, Arabic:بورصة) is a city in northwestern Turkey and the administrative center of Bursa Province. The fourth-most populous city in Turkey and second-most populous in the ...
.
Development
In the calcaneus, an
ossification center
An ossification center is a point where ossification of the cartilage begins. The first step in ossification is that the cartilage cells at this point enlarge and arrange themselves in rows.Gray and Spitzka (1910), page 44.
The matrix in which t ...
develops during the
4th–
7th week of
fetal development
Prenatal development () includes the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal devel ...
.
Function
Three muscles insert on the calcaneus: the
gastrocnemius
The gastrocnemius muscle (plural ''gastrocnemii'') is a superficial two-headed muscle that is in the back part of the lower leg of humans. It runs from its two heads just above the knee to the heel, a three joint muscle (knee, ankle and subtalar ...
,
soleus
In humans and some other mammals, the soleus is a powerful muscle in the back part of the lower leg (the calf). It runs from just below the knee to the heel, and is involved in standing and walking. It is closely connected to the gastrocnemius mu ...
, and
plantaris
The plantaris is one of the superficial muscles of the superficial posterior compartment of the leg, one of the fascial compartments of the leg.
It is composed of a thin muscle belly and a long thin tendon. While not as thick as the achilles te ...
. These muscles are part of the
posterior compartment of the leg
The posterior compartment of the leg is one of the fascial compartments of the leg and is divided further into deep and superficial compartments.
Structure Muscles Superficial posterior compartment
Deep posterior compartment
Blood ...
and aid in walking, running and jumping. Their specific functions include
plantarflexion
Motion, the process of movement, is described using specific anatomical terminology, anatomical terms. Motion includes movement of Organ (anatomy), organs, joints, Limb (anatomy), limbs, and specific sections of the body. The terminology used de ...
of the foot, flexion of the knee, and steadying the leg on the ankle during standing. The calcaneus also serves as origin for several short muscles that run along the sole of the foot and control the toes.
Clinical significance
![Calcaneus Fracture](https://upload.wikimedia.org/wikipedia/commons/e/e8/Calcaneus_Fracture.jpg)
Normally the
tibia
The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...
sits vertically above the calcaneus (''pes rectus''). If the calcaneal axis between these two bones is turned medially the foot is in an everted position (''pes valgus''), and if it is turned laterally the foot is in an inverted position (''pes varus'').
[''Thieme Atlas of Anatomy'' (2006), p 410]
*
Calcaneal fracture
A calcaneal fracture is a break of the calcaneus (heel bone). Symptoms may include pain, bruising, trouble walking, and deformity of the heel. It may be associated with breaks of the hip or back.
It usually occurs when a person lands on their f ...
, also known as ''Lover's fracture'' and ''Don Juan fracture''
Disease
The talar shelf is typically involved in subtalar or talocalcaneal
tarsal coalition
Tarsal coalition is an abnormal connecting bridge of tissue between two normally-separate tarsal bones. The term 'coalition' means a coming together of two or more entities to merge into one mass. The tissue connecting the bones, often referred ...
.
See also
*
Calcar
The calcar, also known as the calcaneum, is the name given to a spur of cartilage arising from inner side of ankle and running along part of outer interfemoral membrane in bats, as well as to a similar spur on the legs of some arthropods.
The cal ...
*
Bohler's angle
*
Sanders classification
The Sanders classification is a system of categorizing intra-articular calcaneal fractures based on the number of articular fragments seen on the coronal CT image at the widest point of the posterior facet.
Classification
See also
* Foot ...
Additional images
File:Left Calcaneus animation03.gif, Left calcaneus. Animation.
File:Ospied-en.svg, Bones of foot
File:Calcaneus.jpg, 3D rendering of a left calcaneus derived from CT scan data. The calcaneus is white, and the other bones of the foot and ankle are clear to illustrate the position and relationship of the calcaneus to the other tarsal bones.
Notes
References
*
*
*
*
External links
* ()
3D printable calcaneus model free download in STL format (Embodi3D.com)
{{Authority control
Bones of the lower limb
Vertebrate anatomy
Bones of the foot
Tarsal bones