Ankle


Ankle
Ankle
Ankle en.svg
Lateral view of the human ankle
Latin articulatio talocruralis
Gray's subject #95 349
MeSH Ankle+joint

The ankle joint is formed where the foot and the leg meet. The ankle, or talocrural joint, is a synovial hinge joint that connects the distal ends of the tibia and fibula in the lower limb with the proximal end of the talus bone in the foot.[1] The articulation between the tibia and the talus bears more weight than between the smaller fibula and the talus.

The term ankle is used to describe structures in the region of the ankle joint proper.[2]

Contents

Name derivation

The word ankle or ancle is common, in various forms, to Germanic languages, probably connected in origin with the Latin "angulus", or Greek "αγκυλος", meaning bent.

Evolution

It has been suggested that dexterous control of toes has been lost in favour of a more precise voluntary control of the ankle joint.[3]

Anatomy

Bones

The boney architecture of the ankle consists of three bones: the tibia, the fibula, and the talus. The articular surface of the tibia is referred to as the plafond. The medial malleolus is a boney process extending distally off the medial tibia. The distal-most aspect of the fibula is called the lateral malleolus. Together, the malleoli, along with their supporting ligaments, stabilize the talus underneath the tibia. The boney arch formed by the tibial plafond and the two malleoli is referred to as the ankle "mortise." The joint surface of all bones in the ankle are covered with articular cartilage.

Ligaments

The ankle joint is bound by the strong deltoid ligament and three lateral ligaments: the anterior talofibular ligament, the posterior talofibular ligament, and the calcaneofibular ligament.

  • The deltoid ligament supports the medial side of the joint, and is attached at the medial malleolus of the tibia and connect in four places to the sustentaculum tali of the calcaneus, calcaneonavicular ligament, the navicular tuberosity, and to the medial surface of the talus.
  • The anterior and posterior talofibular ligaments support the lateral side of the joint from the lateral malleolus of the fibula to the dorsal and ventral ends of the talus.
  • The calcaneofibular ligament is attached at the lateral malleolus and to the lateral surface of the calcaneus.

Though it does not span across the ankle joint itself, the syndesmotic ligament makes an important contribution to the stability of the ankle. This ligament spans the syndesmosis, which is the term for the articulation between the medial aspect of the distal fibula and the lateral aspect of the distal tibia. An isolated injury to this ligament is often called a high ankle sprain.

The boney architecture of the ankle joint is most stable in dorsiflexion. Thus, a sprained ankle is more likely to occur when the ankle is plantar-flexed, as ligamentous support is more important in this position. The classic ankle sprain involves the anterior talofibular ligament (ATFL), which is also the most commonly-injured ligament during inversion sprains. Another ligament that can be injured in a severe ankle sprain is the calcaneofibular ligament.

Disorders

Fractures

Symptoms of an ankle fracture can be similar to those of ankle sprains (pain), though typically they are often more severe by comparison. It is exceedingly rare for the ankle joint to dislocate in the presence of ligamentous injury alone. However, in the setting of an ankle fracture the talus can become unstable and subluxate or dislocate. People may complain of ecchymosis (brusing), or there may be an abnormal position, abnormal motion, or lack of motion. Diagnosis is typically by X-ray. Treatment is either via surgery or casting depending on the fracture types.

Footnotes

  1. ^ Ankle+joint at eMedicine Dictionary
  2. ^ Ankle at eMedicine Dictionary
  3. ^ Brouwer B, Ashby P. (1992). Corticospinal projections to lower limb motoneurons in man. Exp Brain Res. 89(3):649-54. PMID 1644127

References

  • Anderson, Stephen A.; Calais-Germain, Blandine (1993). Anatomy of Movement. Chicago: Eastland Press. ISBN 0-939616-17-3. 
  • McKinley, Michael P.; Martini, Frederic; Timmons, Michael J. (2000). Human Anatomy. Englewood Cliffs, N.J: Prentice Hall. ISBN 0-13-010011-0. 
  • Marieb, Elaine Nicpon (2000). Essentials of Human Anatomy and Physiology. San Francisco: Benjamin Cummings. ISBN 0-8053-4940-5. 

External links

Media related to Ankle at Wikimedia Commons



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Look at other dictionaries:

  • ankle — (n.) O.E. ancleow ankle, from PIE root *ang /*ank to bend (see ANGLE (Cf. angle) (n.)). The modern form seems to have been influenced by O.N. ökkla or O.Fris. ankel, which are immediately from the Proto Germanic form of the root (Cf. M.H.G. anke… …   Etymology dictionary

  • Ankle — An kle ([a^][ng] k l), n. [OE. ancle, anclow, AS. ancleow; akin to Icel. [ o]kkla, [ o]kli, Dan. and Sw. ankel, D. enklaauw, enkel, G. enkel, and perh. OHG. encha, ancha thigh, shin: cf. Skr. anga limb, anguri finger. Cf. {Haunch}.] The joint… …   The Collaborative International Dictionary of English

  • ankle — [n] joint between leg and foot anklebone, astragalus, bone, talus, tarsus; concepts 392,418 …   New thesaurus

  • ankle — ► NOUN 1) the joint connecting the foot with the leg. 2) the narrow part of the leg between this and the calf. ORIGIN Old English …   English terms dictionary

  • ankle — [aŋ′kəl] n. [ME ancle, ancleou < OE ancleow (& ? ON ǫkkla) < IE base * ang , limb, var. of * ank , to bend > ANGLE1, ANGLE2, Gr ankōn, elbow, ankylos, crooked] 1. the joint that connects the foot and the leg 2. the area of the leg… …   English World dictionary

  • Ankle — The ankle joint is complex. It is made up of two joints: the true ankle joint and the subtalar joint: The true ankle joint is composed of 3 bones: the tibia which forms the medial (inside) portion of the ankle; the fibula which forms the lateral… …   Medical dictionary

  • ankle — /ang keuhl/, n. 1. (in humans) the joint between the foot and the leg, in which movement occurs in two planes. 2. the corresponding joint in a quadruped or bird; hock. 3. the slender part of the leg above the foot. [bef. 1000; ME ankel, enkel (c …   Universalium

  • ankle — n. 1) to sprain, turn, twist one s ankle 2) a well turned ( shapely ) ankle 3) (misc.) ankle deep in mud * * * [ æŋk(ə)l] turn twist one s ankle (misc.) ankle deep in mud a well turned ( shapely ) ankle to sprain …   Combinatory dictionary

  • ankle — 1. n. an attractive woman or girl. (Typically with some.) □ Now, there’s some ankle I’ve never seen around here before. □ Do you get ankle like that around here all the time? 2. in. to walk [somewhere]. □ I have to ankle down to th …   Dictionary of American slang and colloquial expressions

  • ankle */*/ — UK [ˈæŋk(ə)l] / US noun [countable] Word forms ankle : singular ankle plural ankles the part at the bottom of your leg where your foot joins your leg I fell and twisted my ankle. ankle socks/boots (= that come up to your ankle) …   English dictionary