|
Metatarsal Bones
The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the medial side (the side of the great toe): the first, second, third, fourth, and fifth metatarsal (often depicted with Roman numerals). The metatarsals are analogous to the metacarpal bones of the hand. The lengths of the metatarsal bones in humans are, in descending order, second, third, fourth, fifth, and first. Structure The five metatarsals are dorsal convex long bones consisting of a shaft or body, a base (proximally), and a head (distally).Platzer 2004, p. 220 The body is prismoid in form, tapers gradually from the tarsal to the phalangeal extremity, and is curved longitudinally, so as to be concave below, slightly convex above. The base or posterior extremity is wedge-shaped, articulating proximally with the tarsal bones, and by its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Bone
The long bones are those that are longer than they are wide. They are one of five types of bones: long, Short bone, short, Flat bone, flat, Irregular bone, irregular and Sesamoid bone, sesamoid. Long bones, especially the femur and tibia, are subjected to most of the load during daily activities and they are crucial for skeletal mobility. They grow primarily by elongation of the diaphysis, with an epiphysis at each end of the growing bone. The ends of epiphyses are covered with hyaline cartilage ("articular cartilage"). The longitudinal growth of long bones is a result of endochondral ossification at the epiphyseal plate. Bone growth in length is stimulated by the production of growth hormone (GH), a secretion of the Anterior pituitary, anterior lobe of the pituitary gland. The long bone category includes the femora, tibiae, and fibulae of the legs; the humerus, humeri, Radius (bone), radii, and ulnae of the arms; metacarpals and metatarsals of the hands and feet, the Phalanx bone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distal
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermetatarsal Articulations
The intermetatarsal joints are the articulations between the base of metatarsal bones. The base of the first metatarsal is not connected with that of the second by any ligaments; in this respect the great toe resembles the thumb. The bases of the other four metatarsals are connected by the dorsal, plantar, and interosseous ligaments. * The '' dorsal ligaments'' pass transversely between the dorsal surfaces of the bases of the adjacent metatarsal bones. * The '' plantar ligaments'' have a similar arrangement to the dorsal. * The '' interosseous ligaments'' consist of strong transverse fibers which connect the rough non-articular portions of the adjacent surfaces. Synovial membranes The synovial membranes between the second and third, and the third and fourth metatarsal bones are part of the great tarsal synovial membrane; that between the fourth and fifth is a prolongation of the synovial membrane of the cuboideometatarsal joint. Movements The movement permitted between the tar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metatarsophalangeal Joint
The metatarsophalangeal joints (MTP joints), also informally known as toe knuckles, are the joints between the metatarsal bones of the foot and the proximal bones (proximal phalanges) of the toes. They are condyloid joints, meaning that an elliptical or rounded surface (of the metatarsal bones) comes close to a shallow cavity (of the proximal phalanges). The ligaments are the plantar and two collateral. Movements The movements permitted in the metatarsophalangeal joints are flexion, extension, abduction, adduction and circumduction. File:The feet of C. H. Unthan, the armless fiddler Wellcome L0034227.jpg, Left: toes adducted (pulled towards the center) and spread (abducted); right, both feet clenched (plantar flexed) File:Footgym rings1.jpg, The upper foot is clenching (plantarflexing) at the MTP joints and at the joints of the toes; the central foot is lifting the toes (dorsiflexing) at the MTP joints; and the foot flat on the ground off to the side is in a neutral position ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarsometatarsal Joint
The tarsometatarsal joints (Lisfranc joints) are arthrodial joints in the foot. The tarsometatarsal joints involve the first, second and third cuneiform bones, the cuboid bone and the metatarsal bones. The eponym of Lisfranc joint is 18th-19th century surgeon and gynecologist, Jacques Lisfranc de St. Martin. Structure Bones The bones entering into their formation are the first, second, and third cuneiforms, and the cuboid bone, which articulate with the bases of the metatarsal bones. The first metatarsal bone articulates with the first cuneiform; the second is deeply wedged in between the first and third cuneiforms articulating by its base with the second cuneiform; the third articulates with the third cuneiform; the fourth, with the cuboid and third cuneiform; and the fifth, with the cuboid. The bones are connected by dorsal, plantar, and interosseous ligaments. Dorsal ligaments The dorsal ligaments are strong, flat bands. The first metatarsal is joined to the first cuneif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epiphyseal Plate
The epiphyseal plate (or epiphysial plate, physis, or growth plate) is a hyaline cartilage plate in the metaphysis at each end of a long bone. It is the part of a long bone where new bone growth takes place; that is, the whole bone is alive, with maintenance remodeling throughout its existing bone tissue, but the growth plate is the place where the long bone grows longer (adds length). The plate is only found in children and adolescents; in adults, who have stopped growing, the plate is replaced by an epiphyseal line. This replacement is known as epiphyseal closure or growth plate fusion. Complete fusion can occur as early as 12 for girls (with the most common being 14-15 years for girls) and as early as 14 for boys (with the most common being 15–17 years for boys). Structure Development Endochondral ossification is responsible for the initial bone development from cartilage in utero and infants and the longitudinal growth of long bones in the epiphyseal plate. The plate' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tendon
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability to withstand significant amounts of tension. Tendons are similar to ligaments; both are made of collagen. Ligaments connect one bone to another, while tendons connect muscle to bone. Structure Histologically, tendons consist of dense regular connective tissue. The main cellular component of tendons are specialized fibroblasts called tendon cells (tenocytes). Tenocytes synthesize the extracellular matrix of tendons, abundant in densely packed collagen fibers. The collagen fibers are parallel to each other and organized into tendon fascicles. Individual fascicles are bound by the endotendineum, which is a delicate loose connective tissue containing thin collagen fibrils and elastic fibres. Groups of fascicles are bounded by the epitenon, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plantar
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubercle (anatomy)
In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to. In the case of certain orchids and cacti, it denotes a round nodule, small eminence, or warty outgrowth found on the lip. They are also known as podaria (singular ''podarium''). When referring to some members of the pea family, it is used to refer to the wart-like excrescences that are found on the roots. In fungi In mycology, a tubercle is used to refer to a mass of hyphae from which a mushroom is made. In animals When it is used in relation to certain dorid nudibranchs such as '' Peltodoris nobilis'', it means the nodules on the dorsum of the animal. The tubercles in nudibranchs can present themselves in different ways: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligament
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the: * Peritoneal ligament: a fold of peritoneum or other membranes. * Fetal remnant ligament: the remnants of a fetal tubular structure. * Periodontal ligament: a group of fibers that attach the cementum of teeth to the surrounding alveolar bone. Ligaments are similar to tendons and fasciae as they are all made of connective tissue. The differences among them are in the connections that they make: ligaments connect one bone to another bone, tendons connect muscle to bone, and fasciae connect muscles to other muscles. These are all found in the skeletal system of the human body. Ligaments cannot usually be regenerated naturally; however, there are periodontal ligament stem cells located near the periodontal ligament which are involved in the adult regener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wedge (geometry)
In solid geometry, a wedge is a polyhedron defined by two triangles and three trapezoid faces. A wedge has five faces, nine edges, and six vertices. A wedge is a subclass of the prismatoids with the base and opposite ridge in two parallel planes. A wedge can also be classified as a digonal cupola. Comparisons: * A wedge is a parallelepiped where a face has collapsed into a line. * A quadrilaterally-based pyramid is a wedge in which one of the edges between two trapezoid faces has collapsed into a point. Volume For a rectangle based wedge, the volume is :V = bh\left(\frac+\frac\right), where the base rectangle is ''a'' by ''b'', ''c'' is the apex edge length parallel to ''a'', and ''h'' the height from the base rectangle to the apex edge. Examples Wedges can be created from decomposition of other polyhedra. For instance, the dodecahedron can be divided into a central cube with 6 wedges covering the cube faces. The orientations of the wedges are such that the triangle and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
