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Anatomy of the Cervical Vertebrae Many animals with a spine have backbones made up of vertebrae, which are a specific set of bones in the body that serve a very crucial purpose. Among these many bones are those called the cervical vertebrae. These particular vertebrae are composed of seven bony rings that make up the neck where it lies between the bottom, or base, of the skull and the vertebrae in the body’s torso, the thoracic. The following is a brief look at cervical vertebrae anatomy and terminology. These vertebrae, being the thinnest, are also the most fragile of the bones that make up the spinal column. But, thin and fragile as they are, they serve very important functions. They safeguard the spinal column, hold up the head, and aid motion in the head and neck. Cervical vertebrae anatomy may seem complicated, but it will help your understanding if you think of the vertebrae as a stack of fitted parts that almost interlock, sort of like pieces in a jigsaw puzzle. The bones fit together in a column that runs from the head to the chest and are named according to their positions in relation to the other vertebrae. For example, the one at the top is known as the first cervical vertebra, or superior, or C1. The last is known as the seventh cervical vertebra, or inferior, or C7. The C1 vertebra, which supports the head, is called the atlas, after the Greco-Roman myth of Atlas who held the world on his shoulders. The C2 is known as the axis. This is because it is the axis the skull and atlas pivot on when you move your head from side to side. Every cervical vertebra has a thin bone ring which surrounds a large hole in the middle, called the vertebral foramen. This is where the spinal cord is housed. On either side of the large foramen, are the little transverse foramina, little holes which encircle the very crucial arteries and veins that carry blood to and from the brain. Coming out from the arch of the foramen are many bony projections, like arms, that deal with the movement and attachment of muscles in the neck. There is also a thicker piece of bone, called the body, that lies behind the vertebral foramen, constituting the main piece of bone in all vertebrae, except the atlas, C1, or first cervical vertebra. The fundamentals of cervical vertebrae anatomy tell us that the bodies provide strength to the vertebrae while continuing to support the weight of the head and neck. There are also pieces of pliable fibrocartilege between the vertebrae, called intervertebral disks, which cushion the bodies and offer a little in the way of neck flexibility by keeping the vertebrae a small distance apart so they can move around a little. Flat faces alongside the bodies form joints with the neighboring vertebrae and the skull. This construction is partly responsible for our being able to move our necks. Although comparatively small in relation to the rest of the body, or even the rest of the spinal column, cervical vertebrae are crucial. They protect important nerves and blood vessels. They provide support for the head and neck so it doesn’t just go bouncing about. And cervical vertebrae offer increased flexibility which allows the head to move in many directions not otherwise possible.
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Milos Rock u temi Anatomija Kralježak Svaki kralježak nepravilna je kost i ima valjkasto tijelo kojega su gornja i donja ploha malo uleknute. Oblik tijela vratnih kralježaka uglavnom je poprečno jajolik; u prsnih je trokutast, u donjih prsnih i gornjih slabinskih postaje okrugao, a u donjih je slabinskih kralježaka bubrežast.Veličina se tijela kralježaka povećava sve do gornjih križnih kralježak. Na stražnjoj je strani tijela luk kralješka, arcus koji obuhvaća kralježnični otvor. Slaganjem kralježaka u niz kralježnični otvori oblikuju kralježničnu cijev u kojoj je zaštićena kralježnična moždina.Luk je urezan odmah uz tijelo kralješka i to s donje strane dublje, a s gornje strane pliće, pa između kralježaka u nizu nastaju u cijevi kralježnice među kralježnični otvor.U kanalu kralježnice smještena je kralježnična moždina pa kroz među kralježnične otvore njezini živci izlaze u tijelo. Vratni kralješci su do sedmog kralješka naprijed malo viši nego straga.Trnasti su nastavci gotovo vodoravni i na vrhu su rascijepljeni.Poprečni su nastavci također rascijepljeni te imaju otvor kroz koji prolazi kralježnična arterija.Trnasti nastavak sedmog vratnog kralješka osobiti je dugačak i strši u šiji,vertebra prominens. Prvi vratni kralježak je glavonoša, atlas.Nedostaje mu tijelo i trnasti nastavak, zato je sličan prstenu. Drugi je vratni kralježak obrtač, axis i s njegova tijela prema gore strši zub u prednji dio atlasova prstena, koji se okreće oko njega.Stoga se glava pretklanja i zaklanja u zglobu između zatiljne kosti i atlasa, a u stranu se naginje i obrće zahvaljujući svezi između glavonoše i obrtača. Prsni kralješci imaju obostrano na gornjem stražnjem kutu tijela približno kružne zglobne plohe te kružnu zglobnu plohu na vrhu poprečnog nastavka.Manji ili veći dio zglobne plohe nalazi se i na donjem stražnjem kutu tijela (osim u prvog, jedanaestog i dvanaestog prsnog kralješka). Slabinski kralješci su vrlo krupni jer preuzimaju težinu cijelog gornjeg dijela tijela, a najveći je peti slabinski kralježak. Križna kost uglavnom je trokutasta oblika i tvori je pet sraštenih križnih kralježaka.Križna je kost s petim slabinskim kralješkom spojena u vrlo izraženom tupom kutu što strši prema naprijed .Križna je kost u muškarca uža, duža i izrazitije udubljena, a u žena je šira, kraća i plića. Trtična kost nastavlja se na donji kraj križne kosti.Tvori je četiri ili pet koščica, od kojih je najgornja pomično spojena s križnom kosti, a ostale s godinama života srastu.