Genetic and Metabolic Bone Diseases PDF

Genetic and metabolic diseases of bone Prof Dr Sergülen Dervişoğlu  Lameller bone Woven bone 0 0 0 Osteoprogenitör hücreler A, Kemik matriksi sentezleyen aktive oseoblastlar ve çevrelerinde iğsi Osteoblastlargörünümdeki osteoprogenitor hücreler...

Genetic and metabolic diseases of bone Prof Dr Sergülen Dervişoğlu  Lameller bone Woven bone 0 0 0 Osteoprogenitör hücreler A, Kemik matriksi sentezleyen aktive oseoblastlar ve çevrelerinde iğsi Osteoblastlargörünümdeki osteoprogenitor hücreler OSTEOKLASTLAR B, Kemik resorbsiyonu yapan osteoklaslar. 0  osteoblast osteoklast  Metabolic bone diseases Osteoporosis Osteomalacia Rickets Primary hyperparathyroidism Renal osteodystrophy Paget disease  Osteoporosis decreaseinbone density Reduced bone mass Normal chemical composition Fully mineralized Localized or diffuse Entire skeleton Excess resorption/decreased formation  Pathogenesis Age related changes—osteoblasts in elderly —reduced reproductive and biosynthetic potential Senile osteoporosis---low turnover rate Proteins in the matrix---diminished capacity to make bone  Pathogenesis Increased parathormon levels or function Insufficient vit-D intake Calcium deficiency during rapid bone growth  Pathogenesis Postmenopausal osteoporosis Hormone dependent acceleration of bone loss 30-40 years after menopause 35% of cortical and 50% of trabecular bone loss Osteoporotic fractures Estrogen deficiency  Pathogenesis Regional osteoporosis Incidental finding on X-rays Immobilized limb ( more than 4 weeks)  Osteoporosis can be classified as primary or secondary. Primary osteoporosis is simply the form seen in older persons and women past menopause in which bone loss is accelerated over that predicted for age and sex. Secondary osteoporosis results from a variety of identifiable conditions that may include: Metabolic bone disease, such as hyperparathyroidism newabnormalgrowthoftissue formationof Neoplasia, as with multiple myeloma or metastatic carcinoma Malnutrition Drug therapy, as with corticosteroids Prolonged immobilization Weightlessness with space travel  Pathogenesis Secondary osteoporosis Drug theraphy Glucocorticoids---affect osteoblasts---inhibition of differentiaiton of preosteoblasts Anticonvulsants Thyroid hormones Endocrine disorders ( DM, Cushing, Acromegaly, hyperparathyroidism and hyperthyroidism)  Modifiable risk factors that may potentiate osteoporosis include: Smoking Alcohol abuse Excessive caffeine consumption Excessive dietary protein consumption Lack of dietary calcium Lack of sunlight exposure (to generate endogenous vitamin D)  Morphology Structurally weak bone Loss of trabecular bone Enlargement of marrow space Cortical porosity Reduction in cortical thickness Increased risk of fracture Pain and deformity Solda normal vertebra, sağda kompresyon kırıkları nedeniyle kısalmış vertebra Osteoporotik vertebrada, horizantal trabeküllerde kayıp ve vertikal trabeküllerde kalınlaşma dikkat çekmektedir. Downloaded from: StudentConsult (on 5 May 2010 06:13 AM) © 2005 Elsevier 0  Risk factors for osteoporosis include: Female sex Age > 70 years Caucasian or Asian race Early onset of menopause Longer postmenopausal interval Inactivity, especially lack of weight bearing exercise  Peer mineralization Osteomalacia of bone matrix Defective mineralization of trabecular and cortical bone matrix Adults Common complication of renal failure Secondary vit D deficiency  Osteomalacia Weakness Diffuse bone pain Easy fatigability and malaise Weakness of proximal muscles Curvature of long bones and spine Coxa vara and kyphosis  The lamina dura may be especially thin in individuals with long-standing or severe osteomalacia. The teeth are not altered in this condition in as much as...  Osteomalacia Failure of mineralization Accumulation of excess amounts of osteoid Surface of bone trabeculae Abnormally soft bones Increased thickness of osteoid seams Radiology loss of normal bone density---osteopenia  Rickets Defective mineralization of epiphyseal growth plate cartilage Vit D deficiency Dietary lack Lack of cutaneous exposure to UV light Malabsorption ( Coeliac dis., pancreatic insufficiency, hepatobiliary disease) Abnormal metabolism ( drugs, renal failure, tumor association) pchildhead padulthood hyperparathyroidi  Hyperparathyroidism Resorbed bone Replacement by small irregular new bone Loss of normal bony architecture Marrow space filled with fibrous tissue Cystic degeneration Osteitis fibrosa cystica---von-Recklinghausen’s disease of bone Giant cell tumor of bone resemblence---brown tumor ( hemosiderin pigment) Reversible Paratiroid adenoma Ektopik adenoma Thyroid parathyroid excess  Beethoven began to lose his hearing at age 28. By age 44, his hearing loss was complete, most likely caused by compression of the eighth cranial nerve associated with Paget's disease of bone. Beethoven's head became large, and he had a prominent forehead, a large jaw, and a protruding chin (see picture)—features that are consistent with Paget's disease. Eventually, his hat and shoes did not fit because of bone enlargement. The cause of Beethoven's deafness is unknown, but it has variously been attributed to syphilis, lead poisoning, typhus, auto- immune disorder (such as systemic lupus erythematosus), and even his habit of immersing his head in cold water to stay awake. The explanation, from the autopsy of the time, is that he had a "distended inner ear" which developed lesions over time.  Paget disease of bone Chronic osteolytic and osteosclerotic disease Uncertain cause One or more bones Pain, skeletal deformities Sarcomatous transformation ,  It is a chronic disorder that typically results in enlarged and deformed bones. The disease is named after Sir James Paget, the British surgeon who first described it in 1877. The excessive breakdown and formation of bone tissue that occurs with Paget's disease can cause bone to weaken, resulting in bone pain, arthritis, deformities, and fractures.  Paget (osteitis deformans) Etiology unknown Intranuclear inclusisons in osteoclasts--- viral? Fifth decade, male predominance Geographical variations Deformity, fractures,deafness, arthritis Flat bones/acral ends of long bones  lion like face Paget disease/ leon facies Paget secondary osteomyelitis  Bone pain is the most common symptom. Bone pain can occur in any bone affected by Paget's disease. It often localizes to areas adjacent to the joints. Headaches and hearing loss may occur when Paget's disease affects the skull. Pressure on nerves may occur when Paget's disease affects the skull or spine. Somnolence (drowsiness) due to vascular steal syndrome of the skull. Paralysis due to vascular steal syndrome of the vertebrae. Increased head size, bowing of limb, or curvature of spine may occur in advanced cases. Hip pain may occur when Paget's disease affects the pelvis or thighbone. Damage to joint cartilage may lead to arthritis. Teeth may spread intraorally - due to the intra-oral force placed on the anterior teeth (especially maxillary central and lateral incisors) by the labial tissues, especially the muscles. Chalkstick fractures. Mosaic bone pattern  Prognosis The outlook is generally good, particularly if treatment is given before major changes in the affected bones have occurred. Any bone or bones can be affected, but Paget's disease occurs most frequently in the spine, skull, pelvis, thighs, and lower legs. In general, symptoms progress slowly, and the disease does not spread to normal bones. Treatment can control Paget's disease and lessen symptoms but is not a cure. Osteogenic sarcoma, a form of bone malignanat tumor, is an extremely rare complication that occurs in less than one percent of all patients. , achondroplasia Akondroplazi kondrodisplazi 0 0  Osteogenesis imperfecta Rare, hereditary disorder Defects in the synthesis or structure of collagen type I Joints, teeth, eyes, ears are affected Reduced matrix formation, crowded osteocytes Deformity from spontaneous fractures, bowing Thin cortices( defect in periosteal bone formation)  Osteogenesis imperfecta Epiphyses are broad, disorganized Blue sclerae---decreased collagen content Translucensy, choroid visualization Misshapen, blue-yellow teeth—def. Of dentin Hearing loss---abnormality in middle/inner ear bones Osteogenesis imperfecta Blue sclerae 8. Nerve pressure Fragile bones  OSTEOPETROSIS Hereditary disease Osteoclast dysfunction Diffuse symmetric skeletal sclerosis Anemia, infections due to leukopenia Increased density in bones Deafness, blindness--- narrowing of exit foramina Osteopetrosis Osteoclast dysfunction Marble bone disease Fibrous stroma Woven bone Chinese letter-like woven bone  Ekxtraskeletal calcification/ossification Postravmatic reactive /heterotopic bone formation – kalça protez operasyonu sonrası – spinal kord zararlanmaları sonrası görülebilir Myositis ossifikans ;heterotopic bone formtion at muscle tissue  Localized posttravmatic myositis ossificans Post travmatic Acute or chronic trauma Multipl enjections Muscle destruction Young male patients Red and painful at trauma side Edematous surface Painfull and restricted chin movement male predominance