Joints of the foot bones

The bones of the foot are connected to the bones of the lower leg (ankle joint) and to each other. The bones of the foot form the connections of the tarsal bones, the bones of the metatarsus, and the joints of the toes.

The joints of the tarsus bones are represented by the subtalar, talon-calcaneo-navicular, transverse joint of the tarsus, heel-cuboid, klinoladevidny and tarsus-metatarsal joints, strengthened with tightly spaced back and plantar ligaments.

Subtalar joint (art. Subtalaris) is formed by the connection of the posterior talus joint surface (calcaneus) and the posterior calcaneus articular surface (talus bone). Joint surfaces conform to each other in shape. Motions relative to the sagittal axis are possible.

The Tar-calcaneus-navicular joint (art talocalcaneo-navicularis) is formed by the articular surface of the head of the talus, articulating with the scaphoid bone in front and the heel bone - below. The joint capsule is strengthened along the edges of the articular surfaces. The joint is strengthened by several ligaments. The interosseous talural calcane ligament (lig. Talocalcaneum interosseum) is very firm, located in the axillary axilla, connecting the surfaces of the grooves of the talus and heel bones. The plantar calcaneoclavicular ligament (lig. Calcaneonavicular plantare) connects the lower medial side of the talus support and the lower surface of the scaphoid bone. The talon-navicular ligament (lig. Talonavicular) connects the posterior surface of the collar of the talus and the scaphoid bone.

The movements in this joint occur together with a subtalar joint around the sagittal axis. The talus bone remains fixed when performing the lead and lead. Together with the turning scaphoid and calcaneal bones, the entire foot moves. When the foot is brought up, its medial edge is raised, and the rear of the foot turns to the lateral side. When the foot is withdrawn, its lateral edge is raised, and its rear surface turns medially. The total volume of movements in this joint relative to the sagittal axis does not exceed 55 °.

The heel-cube joint (art calcaneocuboideum) is formed by the articular surfaces of calcaneal and cuboidal bones facing each other. The joint is saddle-shaped. Its articular surfaces are congruent, and the movements are limited. The joint capsule is strengthened mainly with a long plantar ligament (lig. Plantare longum). This ligament begins on the lower surface of the calcaneus, fanwise diverges anteriorly and attaches to the bases of II-V metatarsal bones. A firm and short plantar heel-cube-shaped ligament (lig. Calcaneo-cuboideum plantare) is located nearby .

The heel-cuboidal and talon-navicular (part of the talus-calcaneus-navicular joint) joints are considered as the transverse joint of the tarsi transversa, or the joints of the joints. In addition to the ligaments that strengthen each of these two joints, the joints have a common bifurcated ligament (lig. Bifurcatum), consisting of two parts. The split ligament begins at the lateral margin of the calcaneus. The first part of this ligament is the calcaneoclavicular ligament (lig. Calcaneo-naviculare) attached to the posterolateral edge of the scaphoid bone, the second part - the heel-cube-shaped ligament (lig. Calcaneocuboideum) - to the rear of the cuboid bone. When the bifurcated ligament is cut, the integrity of the foot is disturbed. Therefore, this ligament is called the "key" of the shopar joint.

Klinoladievidny joint (art. Cuneonaviculare) is formed by flat articular surfaces of scaphoid bone and three wedge-shaped bones. The joint capsule is attached at the edges of the articular surfaces. The joint is strengthened by numerous ligaments: back and plantar wedge-shaped, intercostal interclinical, dorsal and plantar inter-wedge. Movement in the joint is limited.

Tarsometral joints (artt. Tarsometatarseae, lisfrankov joints) are formed by flat articular surfaces of the cuboidal and sphenoid bones, articulating with the bones of the metatarsus. There are three independent joints isolated from each other: the joint of the medial wedge and I metatarsal bones, the articulation of II and III metatarsal bones with an intermediate and lateral wedge, as well as a cuboid bone with IV and V metatarsal bones. Joint capsules are tight, attached to the edges of the articulating surfaces. Joint cavities do not communicate with each other. Capsules are strengthened with dorsal and plantar tarsal metatarsals (ligg. Tarsometatarsalia dorsalia and plantaria). Important is the intra-articular interosseous wedge-metatarsal ligament (ligg. Cuneometatarsea interossea). The medial interosseous clyus synovial ligament connecting the medial wedge bone and the base of the metatarsal II is called the "key of the lisfrank joint". Movements in the tarsus, oblate joints are limited.

The intercellular joints (artt., Intermetatarseae) are formed by the bases of metatarsal bones turned towards each other. Joint capsules are strengthened by transverse rear and plantar metatarsal ligaments (ligg. Metatarsdlia dorsalia and plantaria). Between the articular surfaces facing each other in the joint cavities, there are interosseous metatarsalia interossea (ligg. Metatarsalia interossea). Movement in the intertwined joints is limited.

Ptusnefalangovye joints (artt. Metatarsophalangeae) are formed by the heads of metatarsal bones and the bases of proximal phalanges. The articular surfaces of the phalanges are almost spherical in shape, the articular fossa of the tarsal bones are the shape of the oval. The capsule of each such joint is thin, strengthened laterally with collateral ligaments (ligg. Collateralia), from below - plantar ligaments (ligg. Plantaria). The heads of the metatarsal bones are connected to the deep transverse metatarsal ligament (lig. Metatarsale profundum transversum), fused with the capsule of metatarsophalangeal joints. In the metatarsophalangeal joints, flexion and extension relative to the frontal axis (up to a total of 90 °) are possible. Around the sagittal axis, retraction and reduction in small limits are possible.

Interphalangeal joints (artt., Interphalangeae), block-shaped in shape, are formed by the base and head of adjacent phalanges of toes. The joint capsules are loose, attached to the edges of the articular cartilage. Each capsule is strengthened with plantar and collateral ligaments (ligg. Collateralia et ligg. Plantaria). In the interphalangeal joints, flexion and extension are performed around the frontal axis. The total volume of these movements is not more than 90 °.

[1], [2], [3]