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- II. SPECIAL OSTEOLOGY
- Vertebral column – Columna vertebralis
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FACULTY OF MEDICINE ANATOMY 1 locomotor system Libor Páč Ladislava Horáčková Hana Nechutová Brno 2011 Anatomy is one of elementary fields of study of medicine that the future physicians comes in contact with. It is a science of form, organisation, structure, and posture of human body and its parts. It includes not only forms and structures, which are accessible to a human eye (macroscopic), but also structures, which we can only observe after microscopic maximalisation (microscopic). Thus, we can differentiate between macroscopic anatomy and microscopic anatomy. Anatomy is often incorrectly called morphology. Morphology is more general term than anatomy; it represents the summary of all knowledge about organ form and structure, with respect to its development. The following fields can be classified as morphology fields: anatomy, histology, microscopic anatomy, embryology, cytology, physical anthropology and in clinical sense also pathology (pathological anatomy). Anatomy can be studied from various aspects, directions and for various purposes. The elementary anatomical body position For establishing directions is upright position, upper extremities hanging alongside the body with palms inverted forward. In this position, thumb is the external finger; little finger is the internal finger. Basic planes of the body For purposes of spatial orientation. All three types of planes are mutually perpendicular.
Axes Axis originate in the point of intersection of the above planes (longitudinal, sagittal, and transversal). Establishing the directions in the body In the trunk, on the longitudinal axis, we use this indication: cranialis (superior) – direction towards the head, upper (Latin cranium – skull) caudalis (inferior) – direction towards the lower part of body, lower (Latin cauda – tail) On the sagittal axis: ventralis (anterior) – frontal (Latin venter – abdomen) dorsalis (posterior) – backward, rear (Latin dorsum – back) On the transversal axis: lateralis – external, lying further from the median surface (Latin latus – side) medialis – internal, lying closer to median surface middle – intermedius, if we are to determine the middle formation from the formations, where two are in lateral positions, and the third is in-between From other directions: internus – internal externus – external dexter – right sinister – left superficialis – superficial profundus – deep On both extremities, instead of cranialis and caudalis we use the following terms: proximalis – closer from joining extremity to trunk distalis – more distant from joining extremity to trunk In upper extremity: ulnaris – internal, on the ulnar side of bone – ulna radialis – external, on radial side of bone – radius palmaris – palmar, direction in palm (Latin palma – palm) dorsalis – dorsal, direction to the back, dorsum of palm In lower extremity: tibialis – internal, on the inner side of shin bone – tibia fibularis – external, on the side of calf bone – fibula plantaris – solar, direction to the sole of feet (Latin planta – sole, plant sole) dorsalis – dorsal, direction to the dorsum of feet Main parts of human body The body trunk consists of head – caput, neck – collum (its dorsal part name is isthmus – nucha) and trunk – truncus. On the trunk we differentiate chest – thorax (its frontal part is thorax – pectus and dorsal back – dorsum), next belly – abdomen (its dorsal part is indicated as shoulder – lumbus), pelvis – pelvis (with rear part buttocks – nates or clunes). Extremities include right and left upper extremity – membrum superius dextrum et sinistrum and lower right and left extremity – membrum inferius dextrum et sinistrum. Extremities consist of plexus (cingulum membri superioris et inferioris) and free extremity. Free upper extremity consists of arm – brachium, forearm – antebrachium and hand – manus with palm – palma manus, dorsum hand – dorsum manus and fingers – digiti manus. Free lower extremity include thigh – femur, shin – crus (its dorsal side is called a calf – sura) and foot – pes (where the sole is called as planta pedis and dorsal side of foot – dorsum pedis) and toes – digiti pedis. BoNE SYSTEM (Systema Skeletale, OsteologY) I. GENERAL osteologY The skeleton (skeleton) forms firm, solid and mobile support of body. Together with the system of joints it also forms passive locomotive apparatus (muscles represent the active locomotive apparatus). The skeletal system also forms protective capsules for important organs, such as brain, sensual organs, heart, lungs and others. Skeleton system also has other important function, such as being a deposit of mineral substances; its red bone marrow is organ of haematopoiesis, fat cells of yellow bone marrow are an important source of energy. The bone skeleton of each human consists of 202 bones. Skeleton of each adult human weighs about 12 to 14 kg, i.e. about 16 % of body weight. Knowledge of skeleton bones, their parts, surfaces, formations, channels and holes is an essential pre-requisite for understanding chapters of much greater anatomical importance – skeleton as a whole, its spaces and parts, holes, channels, and slits for vessels and nerves, attachments of muscles and ligaments.
A bone – os is an elementary construction element of a skeleton. Based on their form, we classify bones into five basic categories:
Long bones are characterized by its tubous middle sections, to which terminal parts are connected, usually forming joint heads or joint pits covered with joint cartilage. The middle section of long bone (diaphysis) is hollow, often cylindrical. Its jacket forms compact bone (substantia compacta). Hollow part of the diafysis is called the medullar cavity (cavitas medullaris) and it is filled with bone marrow (medulla ossium). Epiphyses (epiphysis) are at both ends filled by spongious bone tissue (substantia spongiosa), which is surrounded by thin layer of compact bone (corticalis). Epiphyses and diaphysis are separated by growth cartilage, epiphyseal (growth) cartilage (cartilago epiphysialis) in course of bone growth. Short bones usually have various shapes; they have thin corticallis on the surface, and spongious bone on the inside. Joint areas form a big part of their surface. Flat bones are formed by external and internal layer of compacta (lamina externa and lamina interna), the spongiosis in-between is called as diploe. They are typical for skull bones. Pneumatized bones have a hollow cavity inside, covered with mucous membrane. They are created by exvagination of the surrounding mucous membrane into the bone (e.g. from nasal cavity into frontal cavity). Saesamoidal bones originate in muscle ligaments, which help in their function or they protect the joint, which has a ligament passing through. Bone structure The bone is formed by two elementary forms of bone tissue (compact and spongiose). Compact – compact bone (substantia compacta) in humans is formed by lamellar bone, which is characteristically organised into concentric lamellas. Havers lamells create concentric cylinders (in the cross-section these are visible as circles) around the bone vessels. The lamellas system around one vessel forms elementary construction bone unit – osteon. On the bone grinding we find in the middle the Havers channel – the remainder of the original vessel can be found inside on the bone grinding. Intersected lamells – are the remnants of the previous ostheons, which were disrupted by bone reconstruction, and replaced with new Havers systems. Superficial lamells – were created by periostal ossification and bone apposition from cambial layers of periost, these don’t form ostheons. Spongiose – spongious bone (substantia spongiosa) forms frames, which are organised either quite irregularly (diploe of flat skull bones) or they are oriented into certain directions (due to pressure on the bone, they are organised into geometrical shapes – trajectories, which in spatial net optimally transmit pressures into the entire bone matter). This organisation of bone trabecules of spongious bone is called bone architectonics. The spongious trabecules are located in short bones, in diploe of flat bones and in epiphyses and metaphases of long bones of extremities. Due to the changes of functional use of the respective bone, the architectonics of bone tissue also changes. Bone marrow (medulla ossium) – fills all hollows cavities in a bone. It is a haematopoietic tissue, which in a living human is of red, yellow or grey color. Red bone marrow (medulla ossium rubra) is active haematopoietic tissue. It is formed by network of reticular connecting tissue, in which red blood cells and blood platelets are created. In adults red marrow is present only in spongious of flat bones. Yellow bone marrow (medulla ossium flava) originates from red bone marrow by extinction of haematopoiesis, when the red bone marrow is being replaced by fat cells. It is a significant energy source of an organism. Grey bone marrow (medulla ossium gelatinosa) originates in senium by loss of fat from yellow bone marrow. It occurs also in patients with very serious diseases (tumors etc.) Periost (periosteum) covers (with the exception of joint surfaces) bone surface. It is a tough fibrous membrane, which has two main layers: external fibrous and internal cambious layer. Fibrous layer is formed with colagenous fibre tissue with few cells, cambious layer has more cells, and also contain more vessels. Vessels from this layer feed 1/3 of compacts and pass into the bone through independent Volkmann channels. Periost firmly adheres to the bone in site of attachment bands and ligaments, it can be peel off in any other site. The periost is fixed to the compacts using fibrous fibres (Sharpey fibres), helping blood vessels and nerves to enter from periost into compacts. Tearing off the periosteum means destruction of vascularisation of relevant bone region, and because of abundant periost innervation, this injury is very painful. The deep periostal layer cambial layer – is a significant source of bone building activity, participating in bone thickness growth, and in bone remodelling after fracture. Endost (endosteum) is covering inner part of bone cavities, and it is of similar structure as periost. It is a thin layer (cannot be peeled away from the bone), its cells can differentiate into osteoblasts and osteoclasts, it can participate in building of calluses in bone fractures, and contributes to bone reconstruction (e.g. at widening of marrow cavity). Bone arteries. Nutrient arteries (arteriae nutriciae) – one such main artery is present in each bone. Main nutritive arteries originated from vessels, which started enchondrous ossification in bones. They are passing sideways across compacta through foramina nutricia, then they are entering into bone marrow, and here they are branching out. On good developed bone, these holes have their specific position, and typical sideways entering into canales nutricii for each bone. Sideways direction of input holes shows which one of the bone growing cartilages was more active during bone growth. Metaphysal arteries (arteriae metaphysariae) are independent arteries, which penetrate into metaphases, in the vicinity of growing plate, and actively participate in ossification, from its diaphysar side. Here, the vessels create numerous knots, where bacterial cells can be captured, and for this reason it is a predilection site of ostheomyelitides of children age. Epiphyseal arteries (arteriae epiphysariae) represent independent vascularisation of epiphyses in period of growth and ossification. They are entering into epiphyses mostly in site of attachment of joint capsules. They die after the ossification is complete, and their role is taken over by metaphyseal and nutritive arteries. Bone veins. Bone veins pass parallel with arteries. Some veins also run through independent channels (in flat skull bones, in caudal thoracic and lumbar vertebrae). Bone innervation. Periost is richly innervated, neural fibres pass from here into Havers systems and into marrow. Presence of great amount receptors for pain and pressure is the cause of hypersensitivity and painfulness of periost. II. SPECIAL OSTEOLOGYThe bone skeleton is divided into two parts – 1. skeleton of head (skull), 2. axial skeleton and 3. limbs skeleton. 2. Axial skeleton Axial skeleton consists of free vertebras (vertebrae), sacral bone (os sacrum), coccygeal bone (os coccygis), ribs (costae) and sternal bone (sternum). Vertebras – Vertebrae Vertebra consists of body – corpus vertebrae with upper and lower sheet (facies terminalis superior and inferior) for connection with intervertebral discs and from vertebral arch – arcus vertebrae. Dorsal edge of vertebral body and vertebral arch border an opening – foramen vertebrale (alongside the whole length of vertebral column a spinal channel is created – canalis vertebralis, through which the spinal cord runs through). The vertebral arch starts with narrowed part – pediculus arcus vertebrae; on its upper and lower edges are notches – incisura vertebralis superior et inferior. Joining of the two notches of two adjoining vertebras results in foramen intervertebrale, through which the spinal nerve runs through. The vertebra has seven projections – non paired spinous projection – processus spinosus dorsal orienting, paired processus transversi and joint projections – processus articulares superiores (cranial directing) and processus articulares inferiores (caudal directing). Spinous and transversal projections serve for muscle attachments. The basic vertebral schedule – vertebral body, vertebral arch, projections and vertebral opening are the same for all vertebras, with exception of first two cervical vertebras – atlas and epistropheus (axis). Cervical vertebras – Vertebrae cervicales (C1–7) They have smallest bodies. Foramen vertebrale is large, of triangular shape, processus spinosi are short, almost horizontally positioned, and with exception C2 and C7 are bifurcated. At C7 (vertebra prominens) spinal projection is long, and usually have cone shaped enlargement. At head flexion it is easy to palpate them. Sixth cervical vertebra (C6) – on its transversal projection has big tuberculum anterius called tuberculum caroticum. Pressing against it can help to stop bleeding from a. carotis communis. Transversal projections include foramen processus transversi for passing artery and vein vertebralis and on lateral side carrying tuberculum anterius et posterius (anterior tubercle is the remainder of the rudimental cervical rib, posterior tubercle is the actual transversal projection). Atlas, Carrier, the first cervical vertebra (C1). Atlas has no vertebral body, it consists of only two arches (arcus anterior and arcus posterior atlantis). Skull and the second cervical vertebra are attached by joint to the atlas. Arcus anterior has tuberculum anterius on its anterior surface, on its posterior surface it has oval joint surface (fovea dentis) for joining with dens axis. Posterior arch has tuberculum posterius atlantis. Lateral vertebral parts (massae laterales) carry on their cranial surface elongated oval cavities – facies articulares superiores – for joining of atlas with occipital bone condyles. Articulating surfaces for joining with second cervical vertebra are oval facies articulares inferiores. Transversal projections are noticeably large and their tuberculum anterius and tuberculum posterius blend together. Foramen processus transversi is created, and from its begins sulcus arteriae vertebralis, which runs in medial direction (encircle massa lateralis from behind), pass on the upper edge of its arch. Atlas is a transitive vertebra; it’s a part of both the atlantooccipital as well as atlantoaxial connection. Axis, Epistropheus, the second cervical vertebra (C2). Axis has tall body that ends with cranial round point, and based on its shape is called tooth of epistropheus – dens axis. Dens axis has oval joint surface on ventral side (facies articularis anterior for adjoining with fovea dentis on anterior arch of atlas). Little surface on back side of dens axis (facies articularis posterior) is in contact with ligamentum transversum atlantis. Dens axis represents the original body of atlas, which grew into the upper area of axis vertebral body. Pedicles are strong, they blend with the vertebral body, and their cranial surfaces form ovale facies articulares superiores axis. The axis, epistropheus is integral part of atlantoaxial joining, in comparison with other cervical vertebras, it is massive and it carries a significant portion of the head weight. Chest vertebrae – Vertebrae thoracicae (Th1-12) The vertebral bodies are enlarging into caudal direction, and have typical characteristic of chest vertebras – joint surfaces on body sides – foveae costales (always cranial and caudal with exception of Th10-12, where there is only one area) for joining with heads of the ribs. Processus transversi of 1st–10th chest vertebra has one articular area (fovea costalis processus transversi) for adjoining with facies articularis tuberculi costae on the neck of the corresponding rib. Processus spinosi of the chest vertebrae are long, running sideways downwards, overlapping in roof form at the point of middle Th vertebras, at the point of caudal Th vertebrae they are short and running dorsally. Processus articulares stand in frontal plane, cranial joint projections are thin, and their joint surface is running dorsally, whereas lower joint projections are stronger with joint surface running in ventral direction. Lumbar vertebrae – Vertebrae lumbales (L1-5) Have big, large and strong bodies of kidney shape. Pedicles are massive; processus spinosi are strong and large (in form of a plate). Joint projections are oriented into sagittal plane (joint surfaces of cranial projections are running medially, at caudal joint projections they are running laterally). Processus costarii are reduced ribs, running transversally, and are located more ventrally, than the original transversal projections. Original transversal projections are significantly reduced, and are bifurcated into two smaller little bumps. Processus accessorius lies at the posterior edge of processus costarius. Short processus mammillaris steps aside at point of the back edge of processus articularis superior.
Vertebral column – Columna vertebralisDuring development the vertebral column is created by about 33 to 34 vertebral basal elements. Vertebral column of adults has only 24 free vertebras in the definite state, because of sacral and coccygeal vertebras growing together, and forming sacral bone (os sacrum) and coccygeal bone (os coccygis).Sacral bone – Os sacrum (S 1-5) Created by synostosis of five sacral vertebras; in case of so-called sacralisation of lumbar vertebra, when it fuses with L5, alternatively with Co1. It consists of 6–7 vertebras. Sacral bone has triangular shape, wide basis running in cranial direction (basis ossis sacri), caudally narrowing into apex ossis sacri. Canalis sacralis runs through sacral bone, which in point area opens as hiatus canalis sacralis. Facies pelvina (facing into little pelvis) is concave and shows apparent lineae transversae – borders of the original vertebral bodies, and on its lateral ends foramina sacralia pelvina devoted for passing of ventral branches of sacral spinal cord nerves can be found. Facies dorsalis is convex, in medial plane, there is crista sacralis mediana – intergrown thorn projections, crista sacralis medialis (fused joint projections) lies medially from foramina sacralia dorsalia and ends caudally just as cornua sacralia, which border opening into spine channel – hiatus sacralis. Crista sacralis lateralis (fused transversal projections) lies laterally from foramina sacralia dorsalia. Pars lateralis Cranial half part carries joint surface area for joining with the pelvis bone – facies auricularis, in the dorsal direction there is a rough surface – tuberositas sacralis. Basis Runs through proximal big, oval, terminal surface area of first sacral vertebra, its arch borders the entrance into canalis sacralis, in the dorsal direction from the surface area. The frontal edge of S1 protrudes ventrally into a pelvic cavity as foremountain – promontorium, processus articulares superiores are oriented into sagittal plane. Apex is oriented caudally, where it has little oval joint surface area for joining with first coccygeal vertebra (Co1). Coccyx bone – Os coccygis (Co 1-5) Coccyx bone is formed by 4–5 rudimental coccygeal vertebra growing together. It is located in the little pelvis, and bands and muscles run from it, as they together create muscular pelvis bottom (diaphragma pelvis). Dorsal coccyx surface is convex, upper edge carries projections – cornua coccygea running cranially (it is a rudiment of arch and joint projections Co1). The tip – apex ossis coccygis is oriented caudally, it is oval and can be bifurcated.
Sternum is a flat bone, located on ventral side of the chest between the ribs, it consists of three parts. Manubrium sterni (handle) – the widest, cranial part of the bone. On its upper edge there is a notch – incisura jugularis (easily palpable), on laterocranial edge there is little joint surface for joining with clavicle bone – incisura clavicularis, below it there is notch incisura costalis for joining with gristle of the first rib. The caudal manubrial edge is covered by cartilage for joining with sternal body in an open dorsal angle, (angulus sterni). Here, on the lateral side, there is a notch (incisura costalis) for joining with cartilage of the second rib. Corpus sterni (sternal body) – the largest part of sternum, long and relatively narrow, on both lateral sides it carries notches for joining with gristles of 2nd–7th rib (incisurae costales). The body synchondrotical attaches to processus xiphoideus (synchondrosis xiphisternalis) by the caudal edge. Processus xiphoideus (sword shaped projection) – the smallest and most caudal sternal part, it often has a small notch for joining with seventh rib gristle. Processus xiphoideus can be of various size and shape, it can be for example bifurcated. Traces of the original division of sternum sometimes persist into the adulthood; the sections not fused together are called sternebrae. Ribs – Costae Ribs are arch shaped bend flat long bones. Together with chest vertebras and sternal bone they create skeleton of chest (thorax). There are 12 pairs. Number of ribs isn’t constant. There can be just 11 or also 13. As a general rule, the rib length gradually increases from first rib to the eight rib, whereas from ninth rib to the twelfth rib the rib length gradually decreases. The twelfth rib is shortest followed by the first rib. The first rib, palpable on a living human, is the second rib. Each rib consists of bone part – os costale, which is larger, and attaches from behind to chest spinal column, and of a minor anterior cartilaginous part – cartilago costalis. Depending on the ending of the gristle part, we differentiate three groups of ribs:
The bone part of each rib has dorsal (vertebral) and ventral (sternal), rib body – corpus costae in the middle. Dorsal end of the rib has a little head – caput costae. Neck – collum costae is found lateral from caput costae, in the interface of neck and body rib there is a little bump – tuberculum costae, which has joint area (facies articularis tuberculi costae) for connection with processus transversi of chest vertebra. Rib body is thin, flat, with a bend – angulus costae and two surfaces (external and internal). The lower edge of the rib has on its inner surface a groove – sulcus costae (intercostal nerves and vessels runs through here), caudal rib edge is sharp – crista costae. Special features Costa prima (the first rib) is located transversally (below the collar bone) and can not be palpable on the body. Sulcus arteriae subclaviae is located on the cranial surface, and little bumps for attachment musculus scalenus anterior et medius are located ventrally and dorsally from arterial groove. Costa secunda (the second rib) has, on its cranial surface, rough surfaces for muscle attachments – tuberculum m. scaleni posterioris. 3. LIMB SKELETON Skeleton of upper limb – Ossa membri superioris Upper limb (membrum superius) is a “communication organ”, which enables connection with the surrounding environment and with its own body. Skeleton of the upper extremity consists of arm girdle plexus – cingulum membri superioris created by shoulder blade (scapula) and collar bone (clavicula) that attach upper extremity to the axial skeleton and from bones of the free upper extremity – pars libera membri superioris. Basis of the arm is an arm bone (humerus), basis of the forearm is radius (radius) and ulna (ulna), skeleton of the hand is created by eight wrist bones (ossa carpi), five ossa metacarpalia and finger phalanges. Shoulder blade – Scapula It is flat type of a bone, located in back muscles. It is attached by a joint to collar bone, clavicle and arm bone, humerus.The shoulder blade has a triangular shape with two flat areas (facies costalis, dorsalis), three edges (margo medialis, lateralis, superior) and angles (angulus superior, inferior, lateralis). Facies costalis is facing the ribs and it is mildly concaved (fossa subscapularis). 3 – 4 rough lines (lineae transversae) for beginning of subscapular muscle start from the medial edge. Facies dorsalis is divided by transversally passing ridge (spina scapulae) into two holes. Both holes, fossa supraspinata and fossa infraspinata, serve as point of origin of muscles of the same name. The ridge begins on medial edge of shoulder blade with triangular field, and passes over its lateral angle, where ends with flat acromion (acromion), palpable on live human body. Acromion has a joint area, for connection with the collar bone – facies articularis acromii. A beak projection – processus coracoideus scapulae ventrolaterally protrudes from the lateral end of the upper edge of the shoulder blade – margo superior. From the medial part (shifted aside of beak projection) there is a notch – incisura scapulae. Muscles shift aside from margo medialis (oriented parallel with spinal column) and margo lateralis scapulae (running sideways upwards). At the lateral angle of the shoulder blade (between margo lateralis and margo superior) there is a pit (cavitas glenoidalis) designed for articulation with the head of humerus. Tuberculum supraglenoidale (beginning of long head m. biceps brachii) is on the cranial edge tuberculum infraglenoidale (beginning of long head m. triceps brachii) is on caudal edge. Collum scapulae is a narrowed part of a gristle on the periphery of cavitas glenoidalis.
Clavicle is a long type bone, located transversally between shoulder blade acromion and sternal bone. It connects them via articular connection. Medial end of clavicle – extremitas sternalis – connecting through facies articularis sternalis with manubrium of the chest bone, lateral end – extremitas acromialis connects by facies articularis acromialis with acromion of shoulder blade ridge. Clavicle is goose-neck shaped bent bone, medially with ventral arch, and lateraly with dorsal arch. Its cranial area is smooth; its caudal area has a lateral rough surface, from which ligaments steps off. Arm bone – Humerus Humerus is typical long bone with two epiphyses and diaphysis. Proximal epiphysis is created by head – caput humeri. Collum anatomicum humeri runs through circumference of head joint surface. On the lateral side of proximal end of humerus there is tuberculum majus humeri, more ventrally there is tuberculum minus humeri. Between the both little bumps there is a groove – sulcus intertubercularis (tendo of long head of m. biceps brachii runs through here). Both bumps continue distally as edges of crista tuberculi majoris and crista tuberculi minoris. Humerus is narrowed under both bumps – collum chirurgicum humeri, site of frequent bone fractures. Diaphysis: about halfway down the external part of a triangularly shaped humeral body there is a rough plane tuberositas deltoidea. Shallow sulcus nervi radialis is running spiral-like in laterodistal direction alongside of dorsal side of humerus. Distal epiphysis: is enlarged towards the sides, and ended with joint areas. The lateral one has spheroid form – capitulum humeri – and connects with joint surface on little head of the radius, the medial one has form of a pulley – trochlea humeri and is designed for articulation with incisura trochlearis ulnae. Above joint surfaces, humerus protrudes on medial side into greater epicondylus medialis and on lateral side into epicondylus lateralis humeri (both epicondyles are serving for beginnings of some antebrachial muscles). Behind the medial epicondyle there is a deeper groove – sulcus nervi ulnaris. Proximally from joint planes on distal humeral epiphysis, there are pits: fossa radialis and capitulum humeri, fossa coronoidea over trochlea humeri and fossa olecrani is dorsally above trochlea. While the elbow joint is in extreme positions, corresponding projection of forearm bones sink into these pits. Radial bone – Radius Radius is a long type of a bone, located on the thumb side of a forearm. Proximal epiphysis: is formed by head – caput radii, on it there is proximally located a pit, serving for joining with capitulum humeri – fovea capitis radii. On the periphery of radial head there is a cylindrical joint plane for connecting with ulna – circumferentia articularis. Diaphysis: radius is narrowed under its head into collum radii. Under radial neck on ventromedial side, there is a rough plane – tuberositas radii (serving for attachment m. biceps brachii). Radial body is distally enlarging, and medially (against ulna) creates a sharp edge for attachment of interosseal membrane – margo interosseus. Distal epiphysis: on its medial edge there is a shallow incisura ulnaris radii for articulation with head of ulnar bone, distal joint plane is called facies articularis carpalis and it is designed for contact with carpal bones. On lateral edge the processus styloideus radii protrudes, it serve the purpose of muscle attachments. Ulna – Ulna Ulna is a long type bone, it lies on the little finger side of a forearm, proximally it is bulkier, distally it is narrowing. Proximal epiphysis: on its dorsal side, has apparent projection – olecranon ulnae. Incisura trochlearis is opening into ventrally direction, articulated in elbow joint with trochlea humeri. Distal edge of notch protrudes ventrally as processus coronoideus (when the forearm is being flexed, it fits into fossa coronoidea humeri). Diaphysis: on the ventrally plane of the bone body, below processus coronoideus, a tuberosity – tuberositas ulnae is located. On laterally side of the diaphysis there is a notch for articulation with capitulum ulnae – incisura radialis ulnae, from its dorsal edge a crista – crista supinatoria protrudes distally. Ulna has triangular body, with its sharpest edge on its laterally side – margo interosseus for attachment of interosseal membrane. Distal epiphysis: ulnar head – caput ulnae is joined with radius using circumferentia articularis capitis ulnae. From dorsomedial edge of caput ulnae, processus styloideus ulnae protrudes, which is palpable on living humans. Carpal bones – Ossa carpi Set of eight carpal bones, is organised into two rows of four bones. Proximal row is created, from thumb side, by:
Distal row is created, from thumb side, by:
These two bone rows, based on their form, configuration joint areas, tuberosities, bands and ligaments, create a bone arch (arcus), which is concaved into palm – sulcus carpi (and this after being completed with lig. carpi transversum - retinaculum flexorum, is transformed into canalis carpi, serving for running finger flexors tendons, and n. medianus). Ossification of carpal bones Carpal bones ossification in children can be monitored using X-Ray images. These which serve for evaluation of child development, so-called bone age.
There are five metacarpal bones (numbered from the thumb side). Metacarpal bone consists of proximally located basis (basis ossis metacarpalis), contacting with distal row of carpal bones, a body (corpus ossis metacarpalis), and distally located heads (caput ossis metacarpalis) are jointly connected with bases of proximal phalanges. Except for I. and V. metacarpal, the metacarpal bones, on its medial and lateral sides, also have joint areas for articulation with adjacent metacarpal bones. Sesamoid bones are constantly bilaterally on the palmar side of the head of thumb metacarpus. Phalanges of hand fingers – Phalanges There are three phalanges digitorum manus for each finger (phalanx proximalis, media et distalis), only the thumb has two (phalanx proximlalis et distalis). Each phalanx has a basis proximally, continues into corpus and ends with a head distally – caput phalangis, of almost trochlear shape. Phalanx distalis has instead of a head the trochlea. Tuberosity – tuberositas phalangis distalis is located on the distal end of a terminal phalanx. Directory: 1411 -> podzim2011 -> ZLAN0131p 1411 -> Examination from Medical Chemistry Autumn 2010 1411 -> Recommended list of diagrams for the Anatomy final examination Skeleton, joints, muscles 1411 -> Osteology function of skeleton 1 Protection 2 Support 3 a mechanical basis for movement 1411 -> General arthrology, synarthrosis, syndesmosis synchrondrosis, synostosis, diarthrosis ZLAN0131p -> General Arthrology Synartrosis ZLAN0131p -> SystEm of skeletal junctions systema articulare, syndesmologia 1411 -> 1. Synarthrosis (connective tissue, cartilage, bone) Download 66.79 Kb. Share with your friends:
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