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44-407: The main bones of the ankle region are the talus (in the foot), the tibia , and fibula (both in the leg). The 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. The articulation between the tibia and the talus bears more weight than that between the smaller fibula and the talus. The ankle region

88-403: A more precise voluntary control of the ankle joint. Talus bone The talus ( / ˈ t eɪ l ə s / ; Latin for ankle or ankle bone; pl. : tali ), talus bone , astragalus ( / ə ˈ s t r æ ɡ ə l ə s / ), 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

132-471: A talus fracture may result in complications and long-term morbidity. A 2015 review came to the conclusion that isolated talar body fractures may be more common than previously thought. A fractured talar body often has a displacement that is best visualised using CT imaging. In case a talus fracture is accompanied by a dislocation, restoration of articular and axial alignment is necessary to optimize ankle and hindfoot function. Dice were originally made from

176-434: Is an artery of the leg . It carries blood to the anterior compartment of the leg and dorsal surface of the foot , from the popliteal artery . The anterior tibial artery is a branch of the popliteal artery . It originates at the distal end of the popliteus muscle posterior to the tibia. The artery typically passes anterior to the popliteus muscle prior to passing between the tibia and fibula through an oval opening at

220-401: Is convex, triangular, or semi-oval in shape, and rests on the plantar calcaneonavicular ligament ; the lateral , named the anterior calcaneal articular surface, is somewhat flattened, and articulates with the facet on the upper surface of the anterior part of the calcaneus . The neck of talus is directed anteromedially, and comprises the constricted portion of the bone between the body and

264-400: Is covered with articular cartilage . The distances between the bones in the ankle are as follows: Decreased distances indicate osteoarthritis . 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 . Though it does not span the ankle joint itself,

308-399: Is found at the junction of the leg and the foot . It extends downwards ( distally ) from the narrowest point of the lower leg and includes the parts of the foot closer to the body (proximal) to the heel and upper surface ( dorsum ) of the foot. The talocrural joint is the only mortise and tenon joint in the human body, the term likening the skeletal structure to the woodworking joint of

352-403: 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 . A number of tendons pass through

396-402: Is semi-cylindrical, and it is flanked by the articulate facets for the two malleoli. The ankle mortise, the fork-like structure of the malleoli, holds these three articulate surfaces in a steady grip, which guarantees the stability of the ankle joint. However, because the trochlea is wider in front than at the back (approximately 5–6 mm) the stability in the joint vary with the position of

440-419: Is used in leg swing as opposed to advancing the whole-body center of mass is not clear. Of all major joints, the ankle is the most commonly injured. If the outside surface of the foot is twisted under the leg during weight bearing, the lateral ligament , especially the anterior talofibular portion , is subject to tearing (a sprain ) as it is weaker than the medial ligament and it resists inward rotation of

484-466: The ball-and-socket -shaped talocalcaneonavicular joint . The talus is the second largest of the tarsal bones ; it is also one of the bones in the human body with the highest percentage of its surface area covered by articular cartilage . It is also unusual in that it has a retrograde blood supply, i.e. arterial blood enters the bone at the distal end. In humans, no muscles attach to the talus, unlike most bones, and its position therefore depends on

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528-422: The flexor hallucis longus . Exceptionally, the lateral of these tubercles forms an independent bone called os trigonum or accessory talus; it may represent the tarsale proximale intermedium . On the bone's inferior side, three articular surfaces serve for the articulation with the calcaneus, and several variously developed articular surfaces exist for the articulation with ligaments. For descriptive purposes

572-403: The intermedium , between the bases of the tibia and fibula , and the fourth centrale , lying in the mid-part of the tarsus. These bones are still partially separate in modern amphibians, which therefore do not have a true talus. The talus forms a considerably more flexible joint in mammals than it does in reptiles. This reaches its greatest extent in artiodactyls , where the distal surface of

616-534: The 7th to 8th intrauterine month an ossification center is formed in the anklebone. The talus bone lacks a good blood supply. Because of this, healing a broken talus can take longer than most other bones. One with a broken talus may not be able to walk for many months without crutches and will further wear a walking cast or boot of some kind after that. Talus injuries may be difficult to recognize, and lateral process fractures in particular may be radiographically occult. If not recognized and managed appropriately,

660-513: The ankle joint dorsiflexion and used to manage clinical symptoms resulting from ankle equinus. Occasionally a human ankle has a ball-and-socket ankle joint and fusion of the talo-navicular joint. 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. It has been suggested that dexterous control of toes has been lost in favour of

704-463: The ankle joint. However, due to the multi-planar range of motion at the ankle joint there is not one group of muscles that is responsible for this. This helps to explain the relationship between the ankle and balance. In 2011, a relationship between proprioception of the ankle and balance performance was seen in the CNS. This was done by using a fMRI machine in order to see the changes in brain activity when

748-437: The ankle region. Bands of connective tissue called retinacula (singular: retinaculum ) allow the tendons to exert force across the angle between the leg and foot without lifting away from the angle, a process called bowstringing. The superior extensor retinaculum of foot extends between the anterior (forward) surfaces of the tibia and fibula near their lower (distal) ends. It contains the anterior tibial artery and vein and

792-406: The anterior tibia where it is attached and blends with the superior extensor retinaculum. Along with that course, the band divides and another segment attaches to the plantar aponeurosis . The tendons which pass through the superior extensor retinaculum are all sheathed along their paths through the inferior extensor retinaculum and the tendon of the fibularis tertius muscle is also contained within

836-432: The body from the lower legs to the foot. The talus has joints with the two bones of the lower leg , the tibia and thinner fibula . These leg bones have two prominences (the lateral and medial malleoli ) that articulate with the talus. At the foot end, within the tarsus, the talus articulates with the calcaneus (heel bone) below, and with the curved navicular bone in front; together, these foot articulations form

880-447: The bone has a smooth keel to allow greater freedom of movement of the foot, and thus increase running speed. In non-mammal amniotes , the talus is generally referred to as the astragalus. In modern crocodiles , the astragalus bears a peg which inserts into a corresponding socket on the calcaneum , and the hinge of the ankle joint runs between the two tarsals; this condition is referred to as "croc-normal"; this "croc-normal" condition

924-484: The central nervous system (CNS). Muscle spindles are thought to be the main type of mechanoreceptor responsible for proprioceptive attributes from the ankle. The muscle spindle gives feedback to the CNS system on the current length of the muscle it innervates and to any change in length that occurs. It was hypothesized that muscle spindle feedback from the ankle dorsiflexors played the most substantial role in proprioception relative to other muscular receptors that cross at

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968-428: The entire proximal facet of the ankle articulation; additionally the anterior ascending process gradually extends increasingly proximally. In modern birds, the astragalus is fused with the tibia to form the tibiotarsus. [REDACTED] This article incorporates text in the public domain from page 266 of the 20th edition of Gray's Anatomy (1918) Anterior tibial artery The anterior tibial artery

1012-519: The foot. Equinus refers to the downard deflection of the ankle, and is named for the walking on the toes in the manner of a horse. This does not occur because it is accompanied by an inward rotation of the foot ( varus deformity ), which untreated, results in walking on the sides of the feet. Treatment may involve manipulation and casting or surgery. Ankle joint equinus, normally in adults, relates to restricted ankle joint range of motion(ROM). Calf muscle stretching exercises are normally helpful to increase

1056-402: The foot: with the foot dorsiflexed (toes pulled upward) the ligaments of the joint are kept stretched, which guarantees the stability of the joint; but with the foot plantarflexed (as when standing on the toes) the narrower width of the trochlea causes the stability to decrease. Behind the trochlea is a posterior process with a medial and a lateral tubercle separated by a groove for the tendon of

1100-423: The fracture with metal implants through an open reduction internal fixation ( ORIF ). Significant recovery generally occurs within four months while completely recovery usually takes up to one year. The initial evaluation of suspected ankle pathology is usually by projectional radiography ("X-ray"). Varus or valgus deformity, if suspected, can be measured with the frontal tibiotalar surface angle (TTS), formed by

1144-569: The joint such as from rolling an ankle or from blunt trauma . Types of ankle fractures include lateral malleolus , medial malleolus, posterior malleolus, bimalleolar , and trimalleolar fractures . The Ottawa ankle rule can help determine the need for X-rays. Special X-ray views called stress views help determine whether an ankle fracture is unstable. Treatment depends on the fracture type. Ankle stability largely dictates non-operative vs. operative treatment. Non-operative treatment includes splinting or casting while operative treatment includes fixing

1188-434: The lateral aspect of the medial malleolus and the medial border of the talus at the level of the talar dome, with a measurement greater than 4 mm being abnormal. Loss of any of these normal anatomic spaces can indirectly reflect ligamentous injury or occult fracture, and can be followed by MRI or CT. Clubfoot or talipes equinovarus, which occurs in one to two of every 1,000 live births, involves multiple abnormalities of

1232-406: The lateral border of the posterior tibial malleolus to the medial border of the fibula, with greater than 5 mm being abnormal. The second is tibiofibular overlap , the horizontal distance between the medial border of the fibula and the lateral border of the anterior tibial prominence, with less than 10 mm being abnormal. The final measurement is the medial clear space , the distance between

1276-422: The mid-longitudinal tibial axis (such as through a line bisecting the tibia at 8 and 13 cm above the tibial plafond) and the talar surface. An angle of less than 84 degrees is regarded as talipes varus , and an angle of more than 94 degrees is regarded as talipes valgus . For ligamentous injury, there are three main landmarks on X-rays: The first is the tibiofibular clear space , the horizontal distance from

1320-399: The oval head. Its upper and medial surfaces are rough, for the attachment of ligaments; its lateral surface is concave and is continuous below with the deep groove for the interosseous talocalcaneal ligament . The body of the talus comprises most of the volume of the talus bone (ankle bone). It presents with five surfaces; a superior, inferior, medial, lateral and a posterior: During

1364-408: The position of the neighbouring bones. Though irregular in shape, the talus can be subdivided into three parts. Facing anteriorly, the head carries the articulate surface of the navicular bone, and the neck , the roughened area between the body and the head, has small vascular channels. The body features several prominent articulate surfaces: On its superior side is the trochlea tali, which

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1408-407: The receptors of the ankle are stimulated. This implicates the ankle directly with the ability to balance. Further research is needed in order to see to what extent does the ankle affect balance. Historically, the role of the ankle in locomotion has been discussed by Aristotle and Leonardo da Vinci . There is no question that ankle push-off is a significant force in human gait , but how much energy

1452-436: The retinaculum. The flexor retinaculum of foot extends from the medial malleolus to the medical process of the calcaneus, and the following structures in order from medial to lateral: the tendon of the tibialis posterior muscle , the tendon of the flexor digitorum longus muscle , the posterior tibial artery and vein , the tibial nerve , and the tendon of the flexor hallucis longus muscle . The fibular retinacula hold

1496-442: The same name. The bony architecture of the ankle consists of three bones: the tibia , the fibula , and the talus . The articular surface of the tibia may be referred to as the plafond ( French for "ceiling"). The medial malleolus is a bony 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

1540-411: The superior aspect of the interosseus membrane. The artery then descends between the tibialis anterior and extensor digitorum longus muscles. It is accompanied by the anterior tibial vein , and the deep peroneal nerve , along its course. It crosses the anterior aspect of the ankle joint , at which point it becomes the dorsalis pedis artery . The branches of the anterior tibial artery are: As

1584-415: The syndesmotic ligament makes an important contribution to the stability of the ankle. This ligament spans the syndesmosis , i.e. 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 bony architecture of the ankle joint is most stable in dorsiflexion . Thus, a sprained ankle

1628-402: The talocrural joint. An ankle fracture is a break of one or more of the bones that make up the ankle joint . Symptoms may include pain, swelling, bruising , and an inability to walk on the injured leg. Complications may include an associated high ankle sprain , compartment syndrome , stiffness, malunion , and post-traumatic arthritis . Ankle fractures may result from excessive stress on

1672-409: The talus bone is divided into three sections, neck, body, and head. The talus bone of the ankle joint connects the leg to the foot. The head of talus looks forward and medialward ; its anterior articular or navicular surface is large, oval, and convex. Its inferior surface has two facets, which are best seen in the fresh condition. The medial , situated in front of the middle calcaneal facet,

1716-433: The talus of hoofed animals, leading to the nickname "bones" for dice. Colloquially known as " knucklebones ", these are approximately tetrahedral . Modern Mongolians still use such bones as shagai for games and fortune-telling , with each piece relating to a symbolic meaning. The talus apparently derives from the fusion of three separate bones in the feet of primitive amphibians; the tibiale , articulating with tibia,

1760-495: The talus underneath the tibia. Because the motion of the subtalar joint provides a significant contribution to positioning the foot, some authors will describe it as the lower ankle joint, and call the talocrural joint the upper ankle joint. Dorsiflexion and Plantarflexion are the movements that take place in the ankle joint. When the foot is plantar flexed, the ankle joint also allows some movements of side to side gliding, rotation, adduction, and abduction. The bony arch formed by

1804-411: The tendons of the fibularis longus and fibularis brevis along the lateral aspect of the ankle region. The superior fibular retinaculum extends from the deep transverse fascia of the leg and lateral malleolus to calcaneus. The inferior fibular retinaculum is a continuous extension from the inferior extensor retinaculum to the calcaneus. Mechanoreceptors of the ankle send proprioceptive sensory input to

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1848-422: The tendons of the tibialis anterior muscle within its tendon sheath and the unsheathed tendons of extensor hallucis longus and extensor digitorum longus muscles. The deep peroneal nerve passes under the retinaculum while the superficial peroneal nerve is outside of it. The inferior extensor retinaculum of foot is a Y-shaped structure. Its lateral attachment is on the calcaneus, and the band travels towards

1892-462: The tibial plafond and the two malleoli is referred to as the ankle " mortise " (or talar mortise). The mortise is a rectangular socket. The ankle is composed of three joints: the talocrural joint (also called talotibial joint, tibiotalar joint, talar mortise, talar joint), the subtalar joint (also called talocalcaneal), and the Inferior tibiofibular joint . The joint surface of all bones in the ankle

1936-405: Was likely ancestral for archosaurs . In dinosaurs (including modern birds) and pterosaurs , the hinge of the ankle instead is distal to the two tarsals. Far rarer are archosaurs with a "croc-reversed" ankle joint, in which the calcaneus bears a peg whilst the astragalus bears a socket. In the theropod dinosaur lineage leading to birds, the astragalus gradually increases in size until it forms

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