Neck Anatomy

The occiput is the back of the head, the skull base.


The occipital bone is a bone odd and median (single bone in the middle) located to the rear (posterior) and below the skull. The occiput is pierced with a hole (the foramen magnum, also called the foramen magnum) to the passage of the medulla oblongata. The medulla is composed of the upper bulge of the spinal cord containing certain key nerve centers such as regulating breathing. The foramen magnum is bordered on two sides by the hypoglossal nerve and occipital by two ducts. These ducts are shaped cradle and articulate with the first vertebra of the cervical spine, that is to say the part of the spine that supports the skull. This vertebra is named atlas (located above the axis or second cervical vertebra). The articulation at this level allows the inclination of the head.

The occipital bone is almost all of the rear wall and the base of the skull. This bone articulates with the two parietal bones and the two temporal bones through the lambdoid sutures and occipito-mastoid.

The occipital bone is also met the sphenoid bone of the skull base through a narrow blade bone (basilar part of occipital).

Seen from the inside of the skull, the occiput is the walls of the posterior cranial fossa delimiting the cerebellum.
  
The occipito-frontalis muscle is a muscle in two parts (known as belly or middle part), that is to say, the belly and belly frontal occipital. Both bellies are connected by the epicranial aponeurosis. The action of these muscles is as follows: they pull the scalp alternately back and forward.

Neck: Definition

The nape is the back of the neck located below the occiput.


Occipital syndrome (in English occipital syndrome) is characterized by the occurrence of a set of symptoms due to impairment of the brain's occipital lobe (back of the brain). Symptoms include (partial list):

Visual disorders characterized primarily by the appearance of a homonymous hemianopia without involvement of the macula. The hemianopsia is the loss or diminution of vision in one half of the visual field of one eye or two eyes more often. The term homonym means an injury or disorder on the two bodies on the same side, that is located both on the right or left of the median plane (passing through the center of the body). The macula is the depression at the back (posterior) of the retina. Also known as yellow spot, the macula is the area of ​​the retina most sensitive light.
A blind psychic in nature when the lesion is located on the left.
Visual hallucinations.
The occipitalisation of the atlas is the malformation of the area which hinge between the skull base (that is to say the occiput) and the first cervical vertebrae: the atlas. This alteration of the morphology of the skeleton of this part of the neck is characterized by total or partial fusion of the two bones.

Encephalomyelitis is a term derived from the Greek enképhalos: brain and muélos: marrow that means inflammation of the central nervous system (spinal cord). In this condition the patient complains of the following (not exhaustive):

Headache (headache)
Stiff neck
Visual disturbances
Mental and motor disturbance
This neurological disease is sometimes observed after some eruptive fevers. Its evolution is almost always to recovery with or without sequelae.
Some patients encephalomyelitis following an infection by a virus of the Heine-Medin disease.

The hemangiopericytoma is a variety of angioma, occurrence of rare, constituting some of brownish skin tumors appearing mainly on the trunk legs, neck. Sometimes this type of condition also applies when the viscera appearing in the form of visceral tumor.
The development of malignant hemangiopericytoma is sometimes. It is then composed of endothelial cords surrounded by many pericytes that is to say cells with capabilities similar to contraction and smooth muscle cells lining the vessel walls.

The lichen albus von Zumbusch is a variety of lichen porcelain (from Gougerot) based generally on the neck and is characterized by papules that coalesce sometimes white porcelain cupboard rolling contours are angular.

The maduromycose, also called hyphomycétome is a variety of mycetoma, whose type is the disease or Madura foot, may also occur in the neck, and characterized by grains containing large hyphae, fragmented and leading the most often chlamydospores. Slight causes are fungi (maduromycètes), usually Madurella mycetoma, Leptospharia senegalensis and Allescheria boydii.

Münchmeyer's disease is characterized by the production of bone tissue (bone cells) within the same muscle and around him, in the tendons and fascia (membranes covering and protecting muscles). This disease begins early in life through the back muscles and neck and then gradually invades the whole of the musculature.

Acute bulbar paralysis of Leyden, acute bulbar palsy in English, refers to acute inflammation of the basal ganglia located in the medulla (lower polioencéphalite acute) that begins suddenly with headache, pain in the neck, vertigo. This quickly led to a paralysis vélopalatine (soft palate) and sometimes a facial paralysis, dysarthria (slurred speech) and swallowing disorders (difficulty swallowing). Evolution is pejorative, since the death occurs within days. This is preceded by disruption of the cardiac and vascular equipment and sleepiness. This paralysis relates more specifically to individuals intoxicated by alcohol or occurs during the malignant syndrome of certain infectious diseases, the syndrome of Landry or the Heine-Medin disease.

Alopecia areata ophiasique Sabouraud, is a type of alopecia that occurs mainly in children. And that begins with a bald patch at the neck and vertical form. Subsequently plates appear in a horizontal position by adopting the form of wreaths at the lower scalp.

Spiegler's tumor is a tumor of multiple rounded shape, which can reach the size of nine, proliferating at the scalp, sometimes his talents towards the temples, forehead and neck. Analysis of cells constituting the tumor shows the kindness and the fact that the tumor was encapsulated, occasionally lobulated or inground pseudocysts (hence the name cylindroma). It is a hereditary condition which transmission is autosomal dominant.

The rétrocollis is a variety of torticollis in which the head is thrown back because of the contraction of the muscles of the neck.

Posterior cervical sympathetic syndrome is characterized by the onset of headache (headache) occipital (located in back of the skull), dizziness, visual problems and hearing problems. Some patients complain of pain even in the face (facial pain). In some cases the patient hears the cracking in his neck when he moves it. It appears in the rheumatoid cervical spine and probably occur as a result of irritation of the nerve surrounding the vertebral artery (Burtscher-Rochaix syndrome).

Thrombus: Treatment

The fibrinolytic (English fibrinolytic) can dissolve fibrin blood clot. Drugs containing this molecule are particularly used in cases of myocardial infarction. It's all about the streptokinase urokinase, prourokinase and scu-PA.L operation Trendelenburg (in English Trendelenburg's operation) is an opening of the pulmonary artery and remove clots that clog the artery. Without this intervention, pulmonary embolism is likely to be life in danger.Le intravenous filter cellar (in English Endovenous filter) also called Mobin-Uddin filter, filter umbrella filter Greenfield filter umbrella is a device which is introduced into a vena cava catheter. The umbrella filter to stop the migration of clots from the veins of the limbs. This system, usually placed in the inferior vena cava, is to impede the onset or recurrence of pulmonary embolism.

Thrombus: Medical tests

The index of the potential thrombodynamique (IPT) is a number that allows you to get a clear idea, based on the results of thrombo-elastogram, the strength of a blood clot. In some pathologies (structural hypercoagulability), this test is worth practicing. For specialists, the potential thrombodynamique index is calculated by dividing the value of Emx by that of K. The figures are normal between 5 and 10. When they are above 12 is referred to as structural hypercoagulability, when they are less than 5, it is hypocoagulability structurale.Le test Fearnley, called in English Fearnley's test, is the time of lysis is ie destruction of the clot from the blood that was diluted. Fearnley's test is normally more than three hours.The von Kaulla test developed in 1958 (known in English euglobulin lysis test) is synonymous with time measurement of lysis of euglobulins is a method to measure the capacity of destruction of the clot (fibrinolysis) by the blood through the study of fibrinolysis activators, mainly plasminogen. Activators of fibrinolysis are contained in a variety of proteins: the euglobulins. These are precipitated (metropolitan area) by adding an acid (acidification) and then diluted and coagulated. Inhibitors of fibrinolysis, which is part antiplasmin, will float in the liquid obtained. Usually, the clot of euglobulins is destroyed (lysis) after 3 hours, sometimes more. When you get a dissolution (destruction, lysis) faster, it witnessed a plethora of activators and therefore a tendency to fibrinolysis. We talk about: The role is to prevent the normal formation of the clot. Nevertheless, they are the source of certain diseases. These substances consist of antibodies that is to say a variety of proteins belonging to the immune system (defense system of the body). Some of these antibodies are specific to a clotting factor, factor VIII generally. When they are highlighted in the body it means that there is a deficit in the factor responsible. Other anticoagulants cancel the clotting process by intervening at one time or another clotting (phase). This has led to a more global disruption of the body. This is mainly antiprothrombinases. One of the diseases caused by circulating anticoagulant is the lupus erythematosus. In this case it is the lupus anticoagulant or "lupus anticoagulant" by Conley and Hartmann are responsible for this pathology.

Thrombus: Causes

The causes behind the occurrence of thrombosis are relatively numerous. Include (not exhaustive):

Thrombus: Physiology

Specifically, coagulation, causing the formation of a blood clot, can stop the bleeding due to injury among others. This coagulation is first involves a first blood clot color white (platelet thrombus or white) which is caused by platelet aggregation between them: this is the primary hemostasis. The next phase is secondary hemostasis or coagulation itself, corresponding to a sequence of reactions involved in the cascade of proteins that are normally present in blood and specifically in plasma (400 g per liter of blood). These proteins are normally in an inactive state until there is activation that is triggered when certain proteins, particularly factor XII, also known as Hageman factor, comes into contact with the wall of a vessel whose Interior (endothelium) has been damaged or is abnormal. At this point, the contact activation triggers the chain of plasma proteins leading to clot formation. The factors involved in the coagulation cascade are the number of 13. They fall into this complex chain of reactions that results in transforming a soluble protein, fibrinogen, a protein in insoluble fibrin. Fibrin is sort of the skeleton of newly constitué.Le clot clot is the result of the conversion of fibrinogen (which is a variety of proteins) to fibrin (another variety of proteins). Fibrinogen content in blood plasma is produced by the liver and plays an important role in blood clotting. Fibrinogen is also known as coagulation factor I, it is a precursor of fibrin which is part of the cascade described above. Thrombin, another element at play in blood clotting, is another blood protein can activate fibrin. When thrombin-activated fibrinogen, it is converted to fibrin. This will then be polymerized fibrin, that is to say make the joining of many monomers (pieces) and become insoluble as having acquired a stabilization by the intervention of another factor: the factor XIII. From there, a set of proteins is assembled, forming a kind of cap that aims to stop the bleeding: is the filling of the wound by the clot définitif.La clot formation will help to stop relatively rapid bleeding of small vessels when they experience trauma (eg a wound). There are circumstances where there has not been accompanied by trauma but nevertheless hemorrhage: the case of the rules and also in this case, the clot acts as a hemostatic (stop bleeding) . The thrombus appears under pathological conditions, that is to say that it is accidental in a vessel so likely to become blocked. This type of clot occurs in the arteries and veins. When he is in the veins, it is the cause of thrombophlebitis, which in turn could cause a pulmonary embolism (blood clots within the blood circulation of the lungs). When clots form inside the arteries of the general circulation of the body, they are sometimes a source of arterial thrombosis in the coronary (myocardial blood supply vessels, that is to say, the heart muscle), in cerebral arteries (the cause of stroke: stroke) or in the peripheral circulation causing arterial thrombosis, that is to say a decrease in size or even the abolition of passing blood in artères.Physiologiquement is to say, normally in a healthy individual, the clot dissolves after several days, thanks to the intervention of a natural process called fibrinolysis. When necessary, that is to say in the presence of thrombosis, it is possible to accelerate fibrinolysis: it is called thrombolysis. In some cases, it is necessary to intervene surgically to make an unblocking pressure.

Thrombus: Definition

Body obtained after coagulation of blood, half-solid consistency, spongy nature (like a sponge) and consists of a variety of protein: the fibrin in the blood. The clot's role is to retain in its meshes, platelets and red blood cells (RBCs) at the origin of its color very dark red.
The term thrombosis means in turn the formation of a clot (thrombus) in a blood vessel or one of the chambers of the heart in living systems. For some authors this term also refers todisorder that leads to thrombosis.


By extension, the term of thrombosis of choledochal bile Chauffard applies to the formation of large stone that occur within the common bile duct (channel flow in which the bile to the duodenum and confer). The process leading to the formation of this large calculation is as follows: deposition of successive layers of a mixture of cholesterol and bile pigments.
When fresh blood is collected and then brought into contact with air, it quickly turns into a kind of mass, after a few hours, eventually retract and let out (by sweating) a liquid serum which is the liquid part of blood. Indeed, the formed elements (white blood cells, red blood cells and platelets) were retained within the clot and the liquid serum (serum) is the clot on its surface.

The slowing circulation, often the result of a sedentary lifestyle exaggerated. The decay of the vessels and more specifically in the intima, which is to say, the inner wall of the vessels, due to infection or deposits of atherosclerosis (fatty substances). The increase in blood viscosity (decreased hematocrit). In the plasma coagulation Gilbert and Weil (abnormal blood clotting), there is a delay of coagulation, red blood cells have time to settle. The clot then presents a kind of defect, since its upper part, whitish transparent, contains platelets and white blood cells that retract more. It includes a second lower red color more opaque than normal clot. Plasma coagulation for certain severe anemia and is also observed in hemophilia. Syndrome of disseminated intravascular coagulation Hardaway and McKay (in English: Disseminated intravascular coagulation syndrome), also known as DIC, defibrination syndrome, coagulopathy consumption Lasch, is a collection of symptoms characterized by disturbances of blood coagulation due to the disappearance of fibrinogen from the circulating blood. The syndrome of disseminated intravascular coagulation is the result of the sudden onset of activation factors of thrombin leading to fibrin deposition in microvessels leading to their obliteration by thrombosis. They persist longer or shorter. Following this mechanism, the blood becomes incoagulable because it has consumed fibrinogen and other clotting factors (factor V and factor VIII) and platelets. This is the source of bleeding. The hypercoagulability (also called thrombophilia) corresponds to an increase in capacity of the blood to clot. Patients with hypercoagulability the following symptoms: increased speed of blood clotting (known hypercoagulable clotting), the test of tolerance to heparin in vitro and thromboelastography are disrupted, there is also increasing the resistance of the clot (in this case it is a structural hypercoagulability). Blood levels of fibrin and platelets in the blood is higher than normal (see below the lab). Other etiologies (origins) are grouped under the term platelet disorder (qv).