n. (in anatomy) a rounded projecting part, e.g. the projecting part of the chin (mental protuberance).
At the lower end, the bone is enlarged to form 2 lumps (the condyles) that distribute the weight-bearing load through the knee joint. On the outer side of the upper femur is a protuberance called the greater trochanter. The shaft of the femur is surrounded by muscles which move the hip and knee joints.... femur
Arrangement of the bones In childhood, the bones are independent, gradually fusing together by sutures, and in old age fusing completely so that the cranium forms a solid bony case. At the time of birth the growth of several bones of the infant’s head has not been quite completed, so that six soft spots, or fontanellas, present; here the brain is covered only by skin and membranes, and the pulsations of its blood vessels may be seen. One of these spots, the anterior fontanelle, does not close completely until the child is 18 months to 2••• years old.
Parts of the skull The cranium, enclosing the brain, consists of eight bones, while the face, which forms a bony framework for the eyes, nose and mouth, consists of 14 bones. These two parts can be detached.
Shape of the skull The development of large central hemispheres of the brain in humans has in?uenced the skull shape. Unlike in other mammals, the cranium extends above as well as behind the face which therefore looks forwards. The skull’s proportions change with age: the cranium in children is larger in comparison with the face – one-eighth of the whole head – than is the case in adults, where sizes are about the same. Old age reduces the size of the face because of the loss of teeth and absorption of their bony sockets. Women’s skulls tend to be lighter and smoother with less obvious protuberances than those in men.... skull
Decubitus ulcer Also known as pressure or bed sore. Occurs when there is constant pressure on and inadequate oxygenation of an area of skin, usually overlying a bony protuberance. Elderly or in?rm people, or individuals with debilitating, emaciating or neurological illnesses, are vulnerable to the condition. Long-term pressure from a bed, wheelchair, cast or splint is the usual cause. Loss of skin sensation is a contributory factor, and muscle and bone as well as skin may be affected.
Treatment The most important treatment is prevention, keeping the patient’s back, buttocks, heels and other pressure-points clean and dry, and regularly changing his or her position. If ulcers do develop, repeated local DEBRIDEMENT, protective dressings and (in serious cases) surgical treatment are required, accompanied by an appropriate antibiotic if infection is persistent.
Venous ulcer This occurs on the lower leg or ankle and is caused by chronic HYPERTENSION in the deep leg VEINS, usually the consequences of previous deep vein thrombosis (DVT) – see THROMBOSIS; VEINS, DISEASES OF – which has destroyed the valvular system in the vein(s). The ulcer is usually preceded by chronic OEDEMA, often local eczema (see DERMATITIS), and bleeding into the skin that produces brown staining. Varicose veins may or may not be present. Control of the oedema by compression and encouragement to walk is central to management.... ulcer
animals, diseases from See zoonosis. anisometropia Unequal focusing power in the 2 eyes, usually due to a difference in size and/or shape of the eyes, that causes visual discomfort. For example, one eye may be normal and the other affected by myopia (shortsightedness), hypermetropia (longsightedness), or astigmatism (uneven curvature of the cornea). Glasses or contact lenses correct the problem in most cases. ankle joint The hinge joint between the foot and the leg. The talus (uppermost bone in the foot) fits between the 2 bony protuberances formed by the lower ends of the tibia (the shinbone) and the fibula (the outer bone of the lower leg). Strong ligaments on either side of the ankle joint give it support. The ankle allows for up-anddown movement of the foot.
An ankle sprain is one of the most
common injuries.
It is usually caused by twisting the foot over on to its outside edge, causing overstretching and bruising of the ligaments.
Violent twisting of the ankle can cause a combined fracture and dislocation known as Pott’s fracture.... animal experimentation
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