Starting with A for "ACE inhibitor" and continuing through to Y for "Yolk Sac Tumour", we give you succinct explanations for scientific and medical terms in clear and simple words.
- O-linkedrefers to a type of bond that occurs between a carbohydrate side chain and the protein to which it is attached; usually occurs at a serine or threonine residue in the protein
- ObesityBody weight with a body-mass index of over 30 kg/m2, i.e. marked overweight, which leads to impairment of health. Obesity is a risk factor for secondary diseases (particularly metabolic syndrome with diabetes mellitus, hyperlipidaemia, hypercholesterolaemia,hypertension, arteriosclerosis).
- Obstipationsee constipation
- Obstipationsee constipation
- Obstructive JaundiceJaundice (see Icterus) from obstruction of the bile ducts (cf. Bile Ducts).
- Occlusion of the mesenteric arteriesOcclusion of arterial blood vessels of the small intestinal mesentery, which serves the small and large intestine.
1. Acute mesenteric infarct: Caused by arterial embolism with occlusion of the upper or lower mesenterial artery with death of the tissue in the affected intestinal sections.
Symptoms: Typical clinical course in three stages: Initial stage with sudden diffuse body pains, particularly round the navel, which last ca. six hours. There is often no muscular defence in the abdominal wall and lack of pain on pressure; then an interval in which the symptoms improve, the so-called false peace, and which lasts ca. 12 hours. Terminal phase with acute abdominal pain, muscular defence in the abdominal wall, deterioration in the general state (acute abdomen) due to inflammation of the diaphragm, intestinal occlusion and shock with bloody diarrhoea.
Thorough interview of the affected individual by the physician, increased concentration of white blood cells, blood acidity (metabolic acidosis and lactate acidosis), X-ray of the abdomen, ultrasound investigation of the abdominal organs, X-ray imaging of the intestinal vessels with contrast medium.
If possible, operative removal of the embolism in the initial stage, followed by treatment with anticoagulant drugs, perhaps surgical removal of a section of the intestine
Chronic Occlusion of the Mesenteric Arteries
Disturbances in the perfusion of the intestines during occlusive arterial disease, with the symptoms of angina abdominalis. Shunt circulation is mostly well developed and the symptoms are often only mild.
- Occlusive arterial diseaseAbbreviated as OAD
Diseases which are caused by changes which narrow or close arteries and which lead to disturbances in the perfusion of the tissues or organs which they serve. Occlusion of central arteries is mostly isolated and restricted to a single segment. In contrast, occlusion of peripheral arteries may often occur multiply and over long stretches.
1. Peripheral OAD mostly affects the arteries of the legs and feet (ca. 80 %), more rarely the shoulder girdle or arm. 2. Brain (see disturbances in cerebral perfusion), particularly in the jugular artery; 3. Internal organs: see renal arterial stenosis, mesenteric arterial occlusion; 4. Heart: see coronary heart disease
1. Acute: acute arterial occlusion; 2. Chronic: arteriosclerosis, inflammatory diseases of the vessels
Symptoms and diagnosis
The extent and consequences mostly depend on the site and development of the occlusion, the formation or possibility of adequate by-passes (shunts) and the general state of the circulation. The severity of the disturbance in perfusion is assessed with the Fontaine stages. Occlusion in the arteries of the arms and legs can mostly be recognised by interviewing the patient, followed by clinical investigation, particularly appearance (pallor or reddening, ulceration or necrosis), palpation (pulse status) and by listening to accessible arteries with the stethoscope (vessel sounds) and simple tests of clinical function, such as the walking test. Apparative methods include ultrasound diagnosis (Doppler and duplex sonography), angiography and other procedures.
Peripheral OAD treated on the basis of the Fontaine stage. Acetylsalicylic acid in all stages. Stage I: Clinical course monitored; Stage II: particularly walking training. Stages III and IV. Angioplasty (expansion of the vessels with balloon catheter) and operative reconstruction of the vessels. Drugs tried out before amputation.
- occultclinically inapparent
- Ocular fundusalso known as the eyeground
Internal surface of the eyeball, which is visible during examination with the ophthalmoscope. The retina, choroids, optical nerve, yellow spot can be examined and the circulation in the blood vessels directly observed. This assists in the assessment of the clinical course of numerous general diseases (e.g. type 2 diabetes, type 1 diabetes, arteriosclerosis and high blood pressure).
- Oculomotorius paralysisParalysis of the external eye muscles which are served by the Nervus oculomotorius (third cranial nerve), the elevator palpebrae superioris or the internal eye muscles which are served by the parasympathetic side of the Nervus oculomotorius.
Mostly mechanical compression, disturbances in perfusion (e.g. in type 2 diabetes or type 1 diabetes) or inflammation in the region of the nerve.
- Oesophageal VaricesWidening of the veins in the oesophagus to form varicose veins. This can occur in liver damage, particularly in liver cirrhosis (cf. Liver Cirrhosis), if an increase in the blood pressure in the liver leads to the formation of bulges (sacculation) in the blood vessels in front of this. The main danger with oesophageal varices lies in bleeding, which occurs in 30-50% of cases and which is frequently potentially fatal.
Diagnosis: Endoscopy of the oesophagus, X-ray imaging of the oesophagus and stomach with contrast medium.
- OestrogensFemale sex hormones, which are mostly formed in the ovaries, corpus luteum and placenta, but also at low levels in fat tissue, adrenal cortex and testicles. Oestradiol, oestrone and oestriol are important natural oestrogens.
The female menstrual cycle is steered by oestrogens and gestagens. Generally in the first instance by ostrogens, e.g. follicle maturation, initiation of the release of the hormone LH at ovulation (positive feedback, the so-called Hohlweg effect), egg transport, growth of the mucous membrane in the first half of the cycle, composition of the womb's secretions and of vaginal cells. Oestrogens also have actions outside the reproductive organs.
Oestrogens are used in combination with gestagens for hormone replacement therapy after menopause. They are used locally for vaginal inflammation after the menopause, for the treatment of female sterility and for hormonal contraception.
Oestrogen-dependent tumour, liver disease, thrombosis or emboli, vaginal bleeding, high blood pressure and others.
Skin reactions, itching, giddiness, depression, intestinal problems, oedema, increase in weight. The treatment should be discontinued immediately if there are symptoms of thrombosis, emboli, coronary heart disease, heart attack, stroke, migraine-like headache, acute visual problems, increase in blood pressure, abnormal liver values or acute loss of hearing.
- off-label trialan investigational study designed to determine the efficacy or safety of a drug used contrary to the indication, dosage or method of administration approved by the FDA
- OligosaccharidesDesignation for carbohydrates, which are composed of 3-10 monosaccharide units. Cf. monosaccharides.
- Omega fatty acidsMultiply unsaturated fatty acids, which are characterised by specific chemical structures (double bonds between the carbon atoms). Many unsaturated fatty acids cannot be produced by the body alone. These so-called essential fatty acids must therefore be taken in with food. Omega fatty acids reduce blood fat values (particularly triglycerides). Omega-3 fatty acids are especially contained in cold water fish (e.g. herring, salmon). The omega-6 fatty acids include the essential fatty acids linoleic and linolenic acids, which occur in plant oils. eg. lipid reducers.
- OncogenesAlso carcinogenic genes; genes with oncogenic potency.
Genes which can cause malignant growths. Two groups are distinguished.
1. Viral oncogenes: Hereditary information which comes from viruses and is incorporated into cells and which leads to malignant changes in the affected cell; see Viruses, oncogenic.
2. Cellular oncogenes: Natural genes, some of the functions of which are unknown, but which participate in the normal processes of growth and development. These oncogenes are sometimes activated, for example by certain chemicals or radioactive radiation, and can contribute to the development of cancer.
- open-label studya study in which both subjects and investigators know which drug the subjects are receiving
- Oral Hairy LeukoplakiaFlat or raised white deposits on the edge or underside of the tongue which cannot be removed by wiping. Presumably caused by infection with the Epstein-Barr virus when the immune system is disturbed (very frequent in HIV disease). The foci heal spontaneously within months, but may reoccur. Oral hairy leukoplakia is an indication of HIV infection and usually occurs some months or years before full blown AIDS develops.
- Organic nitratesEsters of nitric acid, such as nitroglycerol
Relax smooth muscle, expand veins (more than arteries), with subsequent reduction in the preload and afterload of the heart. The reduction in heart load reduces the requirement for oxygen and can terminate an attack of angina pectoris. Prior treatment can raise the level of stress before the symptoms develop.
To terminate or to prevent an attack of angina pectoris. Termination is carried with orally dosed, rapidly absorbed and short acting nitrates. Prevention may be achieved by nitrate plasters, with absorption through the skin. Also late treatment of myocardial infarction and for heart failure.
Initially often headache, attacks of flushing, occasionally disturbances of the upright stance, drop in blood pressure, reactive increase in heart rate. The activity can decrease in long-term treatment, particularly when this is continuous. Dosage with intervals is therefore recommended.
- Oropharyngeal CarcinomaMalignant tumour of the mouth and throat, mostly round the tongue, the pharyngeal tonsils and the floor of the mouth.
Causes: Frequent after syphilis, liver cirrhosis and during severe iron deficiency (so-called Plummer-Vinson syndrome). Factors which can contribute to the development of cancer include nicotine and alcohol consumption. Oropharyngeal cancer is particularly frequent in India and Sri Lanka, as many people in these countries chew tobacco or betel nuts or smoke small cigarettes with the glowing end in the mouth.
Therapy: Operative removal of the tumour, possibly with neck dissection, subsequent radiotherapy. If the tumour cannot be operated, it is treated with combined radiotherapy and chemotherapy.
- OseltamivirVirostatic drug (neuraminidase inhibitor) for the early treatment of influenza (influenza virus types A and B). Cf virostatic drugs.
Side-effects of the Drug
Nausea, vomiting, heartburn, headache
- osmosisdiffusion of water through a semipermeable membrane in response to a concentration gradient
- Ossificationalso known as osteogenesis
Ossification is the formation of bone tissue. Normal ossification begins in foetuses, with the direct conversion of connective tissue into bones (desmal ossification; e.g. formation of the collarbone and fibrous bones in the skull). The second form of ossification during the development of the foetus is perichondral ossification and in this the bone tissue is formed round the rods of cartilage in the future long bones. The regeneration of this cuff of bone (e.g. after a fracture) is called periostal ossification in adults. The final phase in the development of the foetus is endochondral ossification. This occurs up to the end of longitudinal growth and starts from a specific growth zone between the end and the middle of a long bone. Renewal of bone throughout life (remodelling of bone tissue) is called endostal ossification. Pathological forms of ossification include ectopic ossification, which means ossification of other types of tissue (cartilage, connective tissue, musculature).
- osteitis fibrosa cysticaan inflammatory degenerative condition in which normal bone is replaced by cysts and fibrous scar tissue
- OsteoblastsOsteoblasts are cells which form bone. These cells arise from embryonic connective tissue (mesenchyma). They lie close to the bone at the site of bone deposition and produce uncalcified bone ground substance (osteoid), in which they are gradually enclosed. In this way, osteoblasts are transformed into bone cells which are no longer able to divide (osteocytes). Cf. remodelling of bone tissue.
- OsteochondromaTumour originating in cartilage and bone tissue, also known as ossifying chondroma. The tumour can turn malignant (osteosarcoma). Cf. Bone Tumours.
- Osteoclasia1. increased breakdown of bone substance as a result of activation of the osteoclasts, for example in dialysis osteopathy or primary hyperparathyroidism. Can also be extended to include breakdown because of tumour growth; 2. orthopaedic osteoclasia: Correction of axial malpositioning caused by a badly healed bone fracture or malformation of the tubular long bones from rickets. The affected bone is broken over a cushioned wedge and then fixed in plaster.
- OsteoclastomaAn osteoclastoma is an aggressive bone tumour which grows invasively into bone, but which only rarely forms metastases (lung metastases in 10% of cases, see metastases). The tumour is classified into three groups on the basis of its malignancy: benign, semimalignant and malignant. Osteoclastoma mostly occurs at the ends of the long tubular bones, particularly on the knee. The peak occurrence is between 30 and 40 years of age, with uncharacteristic pain. The affected bone may break spontaneously.
Diagnosis: The diagnosis is made on the basis of X-rays and microscopic investigation of bone tissue samples (biopsy)
Therapy: The affected bone tissue is removed operatively as a whole. The tumour recurs in 50% of cases (relapses).
- OsteoclastsOsteoclasts are giant cells with multiple nuclei which break down bone substance. They often lie in small hollows in the bone substance formed by their own action, the so-called Howship lacunae. Cf. bone tissue.
- OsteocytesOsteocytes are bone cells which are formed from osteoblasts, the cells which form bone. They can no longer divide. Osteocytes are present in small cavities in bone tissue and possess branched extensions into the small channels in the bone, by which they connect to each other. Cf. osteoclasts.
- OsteodensitometryMeasurement of bone density; Procedure for determining the mass of the bone. This is mostly carried out on the spoke of the lower arm (radius), thigh bone (femur) or the lumbar spine, to assess the individual risk of bone fractures or the severity of osteoporosis. Conventional methods are based on the principle of photon absorption (uptake of light energy by the bone) or computer tomography. Measurement of bone density or stiffness are also performed by ultrasound, for example on the heel bone. A decrease in bone density is found in osteoporosis, osteomalacia and other low calcium osteopathies.
- Osteodystrophia deformansAlso known as Ostitis deformans or Paget's disease
Osteodystrophia deformans is the name of a disease which begins insidiously, with changes in one or more bones. In North America most patients are over 50; the disease is rare in Asia.
The disease may be caused by a hereditary predisposition, coupled to viral infection of the cells which break down bone (osteoclasts).
Curvature and thickening of individual long bones. When the skull is involved, the face may be deformed, sometimes accompanied by intense bone pain which resembles rheumatism, tendency to spontaneous bone fractures, neurological symptoms (e.g. paralysis, damage of the spinal chord from pressure from deformed vertebrae, loss of hearing). In advanced stages, a bent carriage may develop.
The disease is usually diagnosed by chance during an X-ray investigation of the skeleton, on the basis of changes in the internal and external sections of the bone. Skeletal scintigraphy is a type of investigation with radioactively labelled substances (cf.scintigraphy) and in the course of such measurements there is increased storage of radioactive markers in the so-called Paget foci. In the laboratory, marked increases are found in alkaline phosphatase and urinary hydroxyproline, a component of collagen.
Calcitonin, bisphosphonates and treatment of the symptoms
- Osteodystrophia fibrosa generalisataalso known as Osteodystrophia fibrosa cystica generalisata or Recklinghausen-Applebaum disease
Osteodystrophia fibrosa generalisata is a disease which is caused by hyperparathyroidism (increased formation of parathormone). It involves a disturbance in the metabolism of calcium phosphate and numerous bone cysts.
Increases in the blood concentrations of calcium and phosphate, frequent kidney stones and irregular bone remodelling, involving decalcification and bone breakdown by osteoclasts, with formation of cavities in the bones. This is accompanied by simultaneous formation of new bone, formation of granulation tissue with spots of bleeding and cysts, particularly on the long tubular bones and more rarely on the skull. This condition has a chronic course, with frequent uncharacteristic rheumatic problems. Cf. dialysis osteopathy.
- Osteogenesissee ossification
- Osteogenesis imperfectaColloquially known as glass bone disease
Osteogenesis imperfecta is a hereditary disease of the cartilage, which leads to increased fragility of the bones. There are multiple defects in the formation in the body of connective tissue.
Types I a, b (Hoeve syndrome, Lobstein disease): mild disease. The conjunctiva is blue and there is premature tooth decay. The teeth are easily worn down and are coloured transparent brown or grey-blue. Loss of hearing; Type II a, b, c (Vrolik disease): Shortening of the long bones, particularly the ribs, as a result of multiple fractures. This is present even at birth. Marked curvature of the long bones. Ends in death; Type III: Severe form with thin curved bones; Type IV a, b: Variable clinical course, with or without involvement of the teeth.
Trials with calcitonin, calciferols or the metabolic products of calciferol plus fluorides. Surgical and orthopaedic care of the bone fractures.
- OsteoidUncalcified bone matrix (matrix ossea), which consists of the so-called ground substance and collagen fibres. Osteoid is produced by the osteoblasts, the cells which form bone. Mineralisation occurs outside the cells (extracellularly).
- OsteoidosteomaThis is a benign bone tumour which produces bone mass. It appears in X-rays as a light zone in the external hard bone tissue, with a border zone. The diameter is rarely more than 2 cm. The tumour mostly occurs in the femur or shin bones.
Symptoms: Bone pains are typical. These can be clearly localised and mostly occur at night. They are alleviated by aspirin (acetylsalicylic acid). In some cases the soft tissue round the bone is swollen.
Therapy: The affected bone is removed by operation (resection) and the resulting cavity filled up with healthy bone (spongioplastic surgery).
- OsteolysisDissolution and degradation of bone tissue, e.g. with bone tumours or inflammation of the bone.
- OsteomalaciaIncreased softness of the bones which tend to bend, as a result of deficient incorporation of minerals into normal or excessive levels of bone ground substance (osteoid), as a form of secondary disturbances in ossification.
Disturbance in calcium or phosphate metabolism, e.g. in kidney disease, deficient nutrition or vitamin D deficiency. Osteomalacia in children or young people is known as vitamin D deficiency rickets (see rickets).
Diffuse skeletal complaints extending to marked restriction to movement as a result of pain.
Lack of visibility of the trabecula (small bars) of the bones in X-rays. Reduction in density of the base and body of the vertebrae, peeling off of the external layers of the bone, particularly in the long bones of the arm and blurred contrast in relation to the internal mass of the bone, sometimes with so-called Looser transformation zones. Early cases are not recognisable in X-rays. Markedly decreased values are found in osteodensitometry. In the laboratory, low levels of blood calcium and sometimes of blood phosphate are found. There are increases in alkaline phosphatase and parathormone.
The treatment of osteomalacia is aimed at normalising bone metabolism. Depending on the cause of the underlying disease, treatment with calcium, phosphate, or vitamin D. A favourable outcome is probable if the bones are not yet deformed.
- osteomyelitisinfection of the bone
- OsteopathyGeneral name for bone diseases.
- OsteopathyGeneral name for bone diseases.
- Osteopathy, alimentaryAlso called hunger osteopathy
A result of deficient diet, in particular deficiency in protein, calcium and calciferols. Fragility of the skeleton with deficient formation of bone tissue (cf. ossification), although the longitudinal growth of the bones is normal. A deficit in sexual hormones caused by deficient nutrition (for instance in anorexia nervosa) can also be relevant to the development of the disease.
Pain in the bones and increased bone fragility, observed as osteoporosis or osteomalacia, with Looser transformation zones and muscular weakness.
- Osteopathy, intestinalName for changes in the skeleton caused by diseases of the gastrointestinal tract which affect the uptake of nutrients. Intestinal osteopathy is mostly a combination of osteoporosis and osteomalacia. Also see Hyperparathyroidism, secondary.
- Osteopathy, low calciumBone changes from a deficiency in calcium, caused either by impaired intestinal uptake of calcium in food or by decreased intake.
- Osteopathy, renalA disturbance in bone metabolism which affects the whole skeleton, accompanied by osteomalacia (which includes unusually soft bones) or osteodystrophia fibrosa generalisata, in patients who have permanent restriction of kidney function or who are on dialysis (see dialysis osteopathy).
Usually disturbance of vitamin D metabolism (see vitamin D), by reduced formation of the active vitamin in the kidney, with reduction in calcium uptake from the intestine and delayed formation of calcium phosphate in the bones.
Pain in the joints and bones, spontaneously occurring bone fractures, weak muscles near the trunk, itching
Calcitriol, calcium, calcium carbonate, sometimes operative removal of most of the adrenals (which produce parathormone). A functionally important residue should remain.
- OsteopeniaOsteopenia is a decrease in bone tissue: 1. physiological age-related decrease in bone mass. In very old people this cannot be distinguished from osteoporosis in practice; 2. stage preceding osteoporosis; 3. collective radiological term for bone diseases which give a diffuse loss of calcification in X-rays and which cannot be classified as, for example, osteoporosis, osteomalacia or osteodystrophia fibrosa generalisata, without further information. Cf. osteopathy, low calcium.
- Osteopetrosis familiarissee marble bone disease
- OsteoporomalaciaCombination of osteoporosis and osteomalacia. Osteoporomalacia occurs, for example, in alimentary osteopathy, intestinal osteopathy, renal osteopathy and age-related (senile) osteoporosis.
Disease of the skeletal system, with loss or reduction in bone substance and structure and increased susceptibility to bone fracture.
The causes of primary osteoporosis (osteoporosis without underlying disease) remain largely unexplained. They could include a lack of the hormone oestrogen in women, particularly after the menopause, and lack of exercise. Secondary osteoporosis (osteoporosis as a secondary disease) can arise from the following underlying diseases: metabolic diseases (e.g. diabetes mellitus), hereditary cartilage diseases, complex bone diseases (e.g. renal osteopathy and intestinal osteopathy) and cancer (particularly of the bone marrow). Secondary osteoporosis can also be due to drugs (e.g. glucocorticoids) or lack of exercise (e.g. bed rest, paralysis of one side of the body).
1. In the state preceding osteoporosis, neither bone fractures nor deformations of the spine occur. A clear reduction in bone mass is nevertheless evident, in comparison with the normal values for the same age and sex.
2. Marked osteoporosis is characterised by at least one fracture from a slight injury or no injury at all, perhaps accompanied by additional fractures. In severe cases there is shortening of the trunk, humpback, transverse skin folds in the region of the flanks and a syndrome of chronic pain, particularly in the area of the trunk. The four clinical stages are based on the mineral content of the bones and the radiological findings in the spine (cf. radiology). The so-called T-score is important here. This describes the deviation of the bone density from the mean value for healthy young adults, relative to the standard deviation (SD).
Stage 0: state preceding osteoporosis (decrease in bone mineral content, T-score -1 to -2.5 SD), no bone fractures;
Stage I: Osteoporosis without bone fractures (bone mineral content decreased, T-score less than -2.5 SD), no bone fractures;
Stage II: manifest osteoporosis with bone fractures (bone mineral content decreased, 1-3 fractures to the vertebral bodies without the application of external force);
Stage III: advanced osteoporosis (bone mineral content decreased, numerous fractures to the vertebral bodies, often additional bone fractures).
Reduction in the bone mass, as found in the measurement of bone density (osteodensitometry), fractures in the base and end-plate of the vertebral bodies, wedge-shaped deformity to the vertebra, cod-fish vertebra, possible histological study of a bone sample from the iliac crest. Laboratory measurements with blood serum (calcium, phosphorus, alkaline phosphatase) are normal.
Occasion for Treatment
1. Osteoporosis without bone fractures should be treated not later than Stage I, or when the bone density has decreased by more than 2.5 standard deviations from the mean bone density for a young adult; 2. Treatment is indicated for marked osteoporosis with fractures to the vertebral bodies.
Primary osteoporosis and postmenopausal osteoporosis in women:
Basic program (reduction of risk factors, calcium rich nutrition, more exercise, gymnastics, additional calcium), hormone replacement treatment with a combination of oestrogens and gestagens. If there is no menstrual cycle, the treatment can be started at any time. Hormone replacement therapy may be supplemented with calcium and also with vitamin D3 (cf. calciferols) for older women, or with a fixed combination of calcium and vitamin D.
Basic program (see above), fluoride, in addition to hormone replacement and additional calcium; alternatively bisphosphonates.
Basic program (see above), analgesics (analgesics); if the osteoporosis is inactive or the bone metabolic rate is low, the bone-forming cells (osteoblasts) can be stimulated with fluorides, such as sodium fluoride. In an acute phase, with, for example, new bone fractures or a high rate of bone metabolism, treatment is with calcium, hormones (oestrogens plus gestagens, calcitonin), the metabolic products of vitamin D (e.g. alphacalcidol) or bisphosphonates.
Treatment as in Stage II. Depending on age and general state of health, possibly only symptomatic treatment (analgesics); possibly anabolic steroids; calcium and vitamin D if there is a high risk of femoral fracture.
Operative treatment of bone fractures, e.g. artificial hip joint for fracture of the femoral neck.
1. Stabilising physiotherapy: strengthening of the musculature of the stomach and back, equilibrium training in combination with isometric motion exercises; 2. respiratory therapy for the frequent restriction to breathing; 3. practice in pressing and pulling, to stimulate the regeneration of bone substance; 4. thermotherapy with fango packs or short wave radiation and baths (melissa or valerian), to improve perfusion and to reduce the perception of pain; 5. regular and moderate periods in the sun or artificial light baths (see light therapy); 6. ergotherapy; 7. calcium-rich nutrition (milk products); avoidance of alcohol and nicotine.
1. Long-term bed rest is in general not necessary after osteoporotic fracture to the vertebral body. 2. Inadequate dosage with analgesics increases physical inactivity and the loss of bone substance (inactivity osteoporosis). 3. It has not been scientifically proved that magnetic field therapy is useful in osteoporosis. 4. The treatment of the underlying disease is part of the treatment of secondary osteoporosis.
Risk factors should be reduced as far as possible. Preventive measures include calcium-rich nutrition (milk products), additional calcium intake, increase in physical activity with, for example, gymnastics. Alcohol and nicotine should be avoided. Moderate exposure to the sun is reasonable.
- OsteosarcomaOsteosarcomas are highly malignant bone-forming tumours with early formation of metastases in the bone marrow or in distant organs. Lung metastases are detectable in 80% of cases, see metastases. Different types of tumour are distinguished on the basis of their dominant cell type (bone cells, cartilage cells, connective tissue etc.) and of the tumours growth pattern (e.g. with blood vessels, in the bone, on the bone, etc.). The tumour mostly occurs at the end of the long tubular bones (44% in the femur near the knee, 17% in the shin bone near the knee, 15% in the humerus (upper arm)).
Osteosarcoma is the most frequent malignant bone tumour, particularly in male children and adolescents. The peak age is in the second decade of life.
Diagnosis: X-rays, computer tomography, nuclear spin tomography and the microscopic investigation of samples of bone tissue (biopsy) are used in diagnosis. The tumour must be distinguished from other tumours, particularly Ewings sarcoma*, osteoblastoma, giant cell tumour and aneurysmatic bone cysts.
Therapy: The therapy consists of multiple chemotherapy and the radical operative removal of the tumour. If there are no remote metastases, the 5-year survival rate is 60-70%.
- OsteosclerosisIncrease in the density of the spongy bone tissue. Sometimes accompanied by thickening of the solid outer layer (cortex) of the bone, in the context of various skeletal diseases. The fragility of the bones is increased, as a result of a lack of elasticity. An increase in the density of the shadows in the bone structures is evident in X-rays. Cf. fatigue fracture.
- Osteosclerosis congenita diffusasee marble bone disease
- Ostitis deformanssee osteodystrophia deformans
- Ostitis fibrosa cystica generalisatasee osteodystrophia fibrosa generalisata
- OTC DrugsOTC is an abbreviation for "over the counter"; OTC drugs are drugs which may be obtained without medical prescription. The supply of freely available drugs can be very different in different countries.
- Otitis mediaInflammation of the middle ear
Infection of the middle ear, which mostly develops in the context of an infection of the rhinopharynx, by transmission through the auditory tube. Viruses or bacteria may cause acute otitis media, e.g. Haemophilus influenzae. Otitis media can have a mild course, with a feeling of pressure, moderate pain and loss of hearing. Severe infections are characterised by intense general symptoms, sometimes accompanied by fever and chills. The treatment includes the causative infection of the upper respiratory tract (see colds), and also perhaps treatment with warmth (red light). If the auditory tube is not cleared within 1-2 weeks of when the infection subsides, treatment of the tube should then follow. Severe cases should always be treated with antibiotics and perhaps with surgery.
- Ovarian CarcinomaSee Ovarian Tumours.
- Ovarian FibromaBenign tumour of the ovaries, which mostly occurs on only one side and which mainly consists of solid connective tissue. It occurs predominantly in women after the menopause, grows slowly and can reach the site of a childs head. A quarter of the patients develop the so-called Meigs syndrome: Formation of abdominal water (ascites) and accumulation of water in the chest (hydrothorax). Both the Meigs syndrome and the fibroma are immediately cured by an operation.
- Ovarian TumoursTumours of the ovaries. As the ovaries consist of many different types of cells, there are numerous types of tumour, depending on the cells from which they originate, and these may be benign or malignant. The benign* tumours include, for example, ovarian fibroma. However, the majority of ovarian tumours are malignant. Malignant ovarian tumours grow very rapidly and are the main cause of death in gynaecological cancer. Risk factors: Ovarian tumours in the family (5-10% of the tumours are familial), advanced age, high levels of fat or meat in the nutrition, sterility, lack of children. Long-term administration of hormonal contraceptives (anti-baby pill), completed pregnancies and breast feeding reduce the risk.
Symptoms: There are no specific symptoms in the early stages of the disease. Disturbances in the menstrual cycle develop late in the disease, including painful menstruation, bleeding after the menopause, diffuse symptoms in the lower body, increase in body circumference and impairment in the general state of well-being.
Diagnosis: Gynaecological palpation, ultrasound investigation, computer tomography, nuclear spin tomography, ventroscopy, operation, laboratory tests.
Therapy: Operative removal of the ovaries and ovarian duct, if necessary also removal of neighbouring organ sections, such as appendix or lymph nodes. After the operation, radiation therapy or chemotherapy may be performed, depending on the type and stage of the tumour.
Prophylaxis: Prophylactic removal of the ovaries is recommended for familial hereditary ovarian tumours.
Individuals suffering from overweight have a raised proportion of body fat. In its wider sense, overweight means a body weight which is above the normal value. Depending on the extent, the World Health Organisation (WHO) distinguishes between overweight, marked overweight (obesity) and extreme overweight (morbid obesity). Overweight in the wider sense is the most frequent form of malnutrition in western industrial countries and is regarded as a risk factor for numerous secondary diseases, such as type 2 diabetes, high blood pressure (hypertension), raised blood cholesterol values (hypercholesterolaemia), hyperlipidaemia, metabolic syndrome, vascular diseases (particularly arteriosclerosis), joint diseases (arthrosis) and sleep apnoea syndrome. Overweight also has an unfavourable effect on diseases which are already present. Studies have shown that pathological overweight increases the risk of death.
Overweight can often be shown to be caused by several factors. Disturbances in the feeling of satiety, family traditions in eating, social environment, psyche, a sedentary way of life, the choice of unhealthy energy rich food and low levels of exercise all support the development of overweight. Metabolism and genetic factors often interact with the way of life in influencing the development of overweight. In 20% of individuals with pathological overweight, the energy turnover is reduced as a result of, for example, low thyroid function, brain disease or intake of certain drugs.
Overweight is characterised by an increase in the proportion of body fat. In women of normal weight this is ca. 20-25% of total weight and in men ca. 15-18%.
A value can be calculated on the basis of the formula for body-mass index (abbreviation BMI) with the help of which it can be recognised whether and to what extent overweight is present. The BMI is calculated from the body weight (kg) divided by the square of the height (m2). According to the WHO classification of BMI, a person with a BMI of from 25.0 to 29.9 kg/m2 has overweight (Class 1), with a BMI of from 30.0 to 39.9 kg/m2 is suffering from obesity or marked overweight (Class 2) and with a BMI of more than 40.0 kg/m2 from so-called morbid obesity or extreme overweight (Class 3). The ratio of hip to waist circumference (waist-hip ratio, abbreviation WHR) is a further parameter and is a measure of the distribution of fat. In men the WHR should be under 1 and in women under 0.8. Higher values suggest that the overweight should be treated, as there is increased risk of metabolic abnormalities and cardiovascular diseases.
Pathological overweight should always be treated, as it is a risk for secondary disease. There are few exceptions, such as advanced age. Treatment is urgent if the overweight is already associated with metabolic diseases such as diabetes mellitus, abnormalities in lipid metabolism or other diseases which are unfavourably affected by overweight (e.g. hypertension, orthopaedic conditions, coronary heart disease). The motivation and self-management of the overweight person is essential for the success of the therapy.
appetite suppressants should only be taken for special medical reasons, as there is the danger of dependence. Conditions for this treatment include combination with a low calorie diet, behavioural therapy and exercise, a BMI of more than 30 kg/m2 and the demonstration of disease which is unfavourably affected by the overweight. Lipase inhibitors decrease the uptake of fat from food.
Operations are only carried out on persons with clearly pathological overweight, i.e. with a BMI of more than 40 kg/m2 or with a BMI of more than 35 kg/m2 with the simultaneous presence of diseases which are unfavourably affected by the overweight. The pathological overweight must have been present for at least five years and not be caused by hormonal abnormalities. Several courses of weight reduction must have been performed before the operation.
Operations should not be carried out on individuals with underlying psychiatric disease, alcoholism or when the risk of the operation is high.
During the operation a so-called gastroplasty is inserted. The resulting reduction in gastric volume causes a more rapid feeling of fullness or satiety. Strict diet is necessary even after the operation, to avoid vomiting after excessive food intake and to achieve effective weight reduction. The expected reduction in weight is between 30 and 70 kg. This treatment may fail if large quantities of highly calorific drinks, mushy food or alcohol are ingested. Secondary operations are often necessary after massive weight (for instance, of the abdominal wall when there is a large apron of fat).
All other operations (bypass in the intestinal area, liposuction of depot fat) are outdated and no longer usual.
Behavioural therapeutic measures should be a component of every treatment of marked overweight. Group discussions or psychological care support the loss of weight and, particularly, improve the long term success.
1. Dietetic therapy: If at all possible, dietetic advice should be given by a specially trained dietetic assistant. The decision whether to use a low calorie mixed diet or a very low calorie diet depends on the concomitant diseases, the urgency of the weight loss, the severity of the overweight and the readiness of the overweight person. Diet should be accompanied by physical endurance training if this is not contraindicated. a) low calorie mixed diet: Energy supply depends on the degree of overweight and the activity of the individual. High fat and high sugar foods and alcohol must be reduced. Fruit, vegetables, wholemeal products, mineral water and tea should be favoured. b) very low calorie diet: A medical examination should take place before the start of the treatment and a weekly medical check-up during the treatment is also required. At least 2 l of zero calorie fluid should be drunk each day. Vitamins and perhaps potassium should also be taken. The expected reduction in weight in four weeks is ca. 10 kg in women and 12 kg in men. This form of diet should not be used with, for example, type 2 diabetes with advanced late complications, cardiac defect, heart failure, severe hypertension, advanced arteriosclerosis, cardiac arrythmia, pregnancy, breast feeding, age under 18 or psychiatric disease. Zero diets and all one sided unscientific forms of fasting are outdated.
2. Physical training: Only endurance sports have a positive effect on metabolism, e.g. swimming, cycling, rowing, walking, mild jogging or ski langlauf. Caution is required, because of the danger of excessive stress on the joints and ligaments. Daily walks are recommended for older people. Exclude contraindications (particularly cardiovascular disease) before starting training.
Regular check of body weight, balanced nutrition, sport several times weekly or plentiful movement. If there is a tendency to overweight, possible reduction in calorie intake.
Glossary entries: Roche and Walter de Gruyter, Berlin