Bone disorders - Lecture notes 1 PDF

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Summary

Type 1 or postmenopausal, in females at 45-55 years. Osteoclasts have estrogen receptors, whose union inhibits their activity. After menopause, by lowering estrogens, osteoclastic activity is exacerbated. Mostly affects the part lock¬Cular, especially in the vertebrae.
+ Type 2 or senile, in b...

Description

Bone disorders Is the loss of bone mass by decoupling between OsteoclasTheosteolisis) and osteoblasts (osteogenesis) by: -Increase of osteolisis. -Decrease in osteogenesis. Causes - Osteoporosis involutiva: + Type 1 or postmenopausal, in females at 45-55 years. Osteoclasts have estrogen receptors, whose union inhibits their activity. After menopause, by lowering estrogens, osteoclastic activity is exacerbated. Mostly affects the part lockCular, especially in the vertebrae. + Type 2 or senile, in both sexes from 65 years. It is probably caused by vitamin D deficiency. It mainly affects the cortical of the bones of the extremities (hip, femur). -Prolonged immobilization. Lack of mechanical stimulus Depresses osteogenesis, producing decoupling. -Endocrine Diseases: + Estrogen deficiency (p.e. After ovarian removal) + hyperthyroidism. excess active thyroid hormones Both osteolisis As Osteogenesis, but desacopladas. + Syndrome Of Cushing's (excess cortisol). Causes osteoporosis due to: "Inhibits protein synthesis, then depresses the activity of osteoblasts. "Inhibits intestinal absorption of Ca + +, producien of Hypocalcemia, which stimulates PTH release, which stimulates osteoliSix. -Hereditary defect of collagen synthesis I, which is what What happens in the osteoporosis of imperfect osteogenesisHe. Symptoms -Decreased bone density. -Dull and low-intensity pain. is produced by the effort that They should make the dorsal muscles to stabilize the altered spine. -Spontaneous fractures or minimal blows. Son CaracterístiThe vertebral microfractures that are deforming the vertebrae. Evidently, the fracture is accompanied by acute pain. Before a fracture of the femur or hip is seen:

+ member shortening. + patient tends to be placed in external rotation. + Sign of the train of the march of Lembourre: You make him put to the paw lame on the healthy leg. "In c.n, the pelvis vascula To the side that supports. "If there is a fracture, the pelvis vascula, But it sinks to the side that does not support, the patient, because it inhibits the contraction muscleTo avoid pain. -Deformation of the vertebrae by the action of repeated microfractures: + in dorsal area, the weight falls on the anterior edge of the vertebral body, which is the one that breaks. This creates a wedge-shaped vertebrae. + In the lumbar area, the weight falls on the center of the vertebrae, which sinks giving an image of "Diabolo"or" fish bone. " These bone deformations have an external manifestation: -old man loses stature, crushing his vertebrae. -The dorsal kyphosis (hump) is accentuated by the wedge shape adopted by the thoracic vertebrae. 2) OSTEOSCLEROSIS It is produced by predominance of osteogenesis. The best known form is Osteopetrosis, which is produced by a An inherited defect in the number of osteoclasts. It is corrected with bone marrow transplantation, which provides a normal number of osteoclasts. Manifestation -Increased bone density. -Pancytopenia (anemia, thrombocytopenia, leukopenia), because the hypertrophic bone leaves a very small medullary cavity. 3) Rickets and OSTEOMALACIA It is the disorders in which the bone suffers a mineralization defect. Bone mass may even be increased to compensate, but it is decalcified. Causes It is produced by a decrease in the plasma concentration of Ca + + and phosphorus, which may be motivated by: A) intestinal malabsorption of Ca + + and phosphorus. b) Vitamin D deficit caused by:

-Insufficient contribution. Malabsorption. -Lack of sunshine. -Severe hepatic failure, where there is no 25-hydroxylation. -Renal failure, because there is no 1-hydroxylation. -Tumor Factor inhibits hydroxylases. -Normal vitamin is formed, but the tissues are made resistant to their action. Drugsp.e. Antiepileptics), which: "They induce their hepatic transformation. "They create a situation of resistance to vitamin D. Other causes are: -Hypophosphatemia without hypocalcemia: + Failure in resorption of P in proximal tubule in "phosphate diabetes" (Rickets vitamin D resis Tent). + Fanconi syndrome. Acidosis. Bone salts are used to use them as tampons against the H +. Manifestation -In Rx Bone areas with lower bone density are seen along with other areas with increased density by hiperóstosis CompensatedOut. [Areas of Looser are erosions caused by the pulses of the aa Nutritional, they look like bands radiotrasparentes Perpendicular to the edge of the bone and symmetrical; In the neck of the femur, pelvis, and shoulder blade. - Seudofracturas. You see lines of discontinuity in the cortical bone, which are not real fractures. -Dull pain, due to irritation of the periosteum when the bones are deformed. deformations. The bones are "soft", and they warp with the pressure lines. Like this: + Pellet-shaped vertebrae. + Pelvis Narrows. + Acetabulum sinks in. [In rickets, as in children, bone modeling is affected: -Wrists and knees very wide, being the conjunction cartilages.

-"Rosario stunted", which is a set of nodules in the joints costocondrales.] PAGET's disease It is the formation of a normal bone tissue in quantity and mineral But with an altered structure. is produced by a RemodelingLie Excessive and abnormal, in which a osteolisis Exaggerated is followed by an osteogenesis also accelerated, but that originates an abnormal bone tissue and very vascularized. The cause is unknown. Maybe virus. Manifestation -In Rx Zones of higher density are altered with others of lower. -dull pain from irritation of the periosteum by increasing the surrounding bone mass. -Bone deformations: + Enlargement of the skull. + lateral bulging of the femur. + Anterior bulging of the tibia. Biochemical data: Calcemia + Osteomalacia > Normal or something low. + Osteoporosis > may be high if it increases osteoliSix - Fosfatemia: + Osteomalacia > Baja. -Alkaline phosphatase. It is produced by osteoblasts and will therefore be increased when osteogenesis increases: + Paget. + Osteomalacia. Osteocalcin. Also product of Osteoblasts It does not increase in parallel to alkaline phosphatase, but increases when it does osteogenesis: + Paget. + Osteoporosis of turnover Fast. -Urinary elimination of Hydroxyproline, index of osteolisis, is increased by: + Paget. Joint Pathology Arthritis

Is the inflammation of the synovial Causes Mechanical + Post-traumatic. The blow causes joint bleeding (hemartros), and the blood produces inflammation. + Precipitation of uric acid crystals (arthritis gouty). They are phagocytoseded by neutrophils, which release their enzymes and attract more leukocytes. -Infectious (septic arthritis). Germs come to the Articulation usually by via hematic. The most frequent are: Staphylococci. " Tuberculosis. " Candida. -Immune Mechanism: + Type III hypersensitivity arthritis. + Rheumatic fever. The Ag is related to the EstreptoCoco, although it is not well known. + Rheumatoid arthritis. It is probably initiated by exogenous factor, which triggers an autoimmune response. The Target. plasmátiSynovial infiltrate CAs produce rheumatoid factor, capable of forming large complexes with itself and immunocompteIf Ig-rheumatoid factor, activating complement. + lupus erythematosus. Deposit of formed Immunocomplexes By nuclear Ag and its Ac. Consequences -Limitation of joint mobility. Functional impotence. -muscular contraction reflects to place the joint in The position that is less painful. It's usually in slight bending, which is how the capsule is more relaxed. -Inflammation destroys the articular cartilage and even Destroy the subchondral bone. The damage occurs mostly in the periphery of the surfaceCIE articular, which is where the synovial contacts the bone. -Inflammation releases mediators (PGs, etc) that activate Osteoclasts, so that osteoporosis is observed in epiphysis yuxtaarticulares. -After curing, mobility is still reduced by fibrosis and even bone fusion (ankylosis). Manifestations

-The joint appears swollen, red and hot. Pain. It is characterized by: + is continuous (need painkillers to sleep) + sharp and very intense. + is heightened by moving the joint so that the Muscles are blocked to prevent pain, and there is functional impotence. -Morning stiffness. At night, inflammatory exudate accumulates in the joint. This one is reabsorbed throughout the morning, with the movements. -Biochemical data: + Generals. Are those of any inflammation: " Anemia. Leukocytosis. "Accelerated sedimentation rate. "Increase in acute phase reactants. + Specific: "Hyperuricemia in gouty arthritis. "Ac Antistreptolysin if ESTREPTOCÓCI infectionAs "Rheumatoid Factor in rheumatoid arthritis. "Ac Antinuclears in Lupus -Synovial fluid: + Increases your quantity. In c.n. It is virtual (1-2 ml), but in the inflammations it accumulates 50-100 ml. + turbid. + Increase in the number of cells (up to 50,000/ml). Of They, up to 70% are neutrophils. + Disminute Glucose, consumed by cells. + Decreases viscosity. -The limitation of joint mobility is explored with various maneuvers (v. more Alante): Arthrosis It is the degeneration of hyaline cartilage from the joints. Causes

-Mechanical overload. articular cartilages that withstand greater load for anatomical reasons are affected (the faces articulateNot fit well, knees withstand all the joint weight) or environmental (obese lower limb, dancer hip ballet, upper member of Stevedore). -Metabolic factors. The deposit of foreign products (Urate in Hyperuricemia, Ac.homogentisínico In AlcaptonuAlters the function of chondrocytes and cartilage properties. -Hereditary factors. They are known to exist, but not how they act. Inflammations. In arthritis, cartilage can be Destroyed by inflammation. Manifestations Pain. is produced by the rubbing of the bare bones of Cartilage, release of substances by the degenerative process, etc. It is characterized by: + is dull and not very intense. + only appears with the movement. + Improves with rest or when the movement persists, as the joint is "heated". -Limitation of joint mobility. -Crackling (joint clicking), rubbing the irregular surfaces. -Deformation of the joint, produced by secondary inflammation and by the proliferation of bone osteófitos. Heberden nodules are typical, deformities excrecenYour In the joints interfalangicas of the fingers. -Biochemical data: non-relevant. -synovial: Slightly lowers the viscosity, and increases tambIén lightly the N º of cells and the proportion of neutrophils. -The osteófitos They are proliferations of cartilage remnants in the cartilage-synovial union, which are then calcified. They are used to extend the joint contact surface. Joint disease Exploration: Inflammation Scan: -Fluctuation of synovial fluid in the knee. With one hand he Squeeze over the quadriceps tendon, and with the other squeeze from below, to see if the fluid goes up. -Patellar shock. He hits his kneecap. The liquid moves To the sides, where we capture it. For small spills. Synovial Fluid Analysis: Mobility Exploration:

-If there is spondylitis (swelling vertebrae), the mobility of the spine is limited, which we explore: + with a straight back, L5 and a point are pointed at 10 cm above you. + Forward bending. The normal point is to move to about 15 cm of L5, to straighten the lumbar lordosis. + If there is spondylitis, the distance is still 10 cm, Well, you can't flex. Maneuverfavere". The leg is placed in flexion-rotation-abduction (holding with the other hand the opposite hip): + with Arthritis It's impossible to do it. + With sacroileítis Yes you can, but once placed in that position, you can not lower your knee. -placed in decubitus prone, grabs the leg and makes it lift about 20 º C. + with arthritis you can't. + With sacroileítis Yes, he can, but he can't raise it anymore. Muscle pathophysiology I. Disorders of the transmission of nerve impulse Presynaptic disorder of the release of Oh: -Eaton-Lambert myasthenic syndrome. is the manifestation A non-metastatic neurological carcinoma (usually oat cell lung cancer). In women, it may also be due to inflammatory diseases and granulomassas. OcasioNally, can cause AUTOINMU diseasesnes, sarcoidosis, tubercuLosis, etc. In these processes it seems that they produce autoantiBodies that bind and block the Ca + + channel. Botulism. It is produced by poisoning with the toxin of Clostridium botulinum, which binds and blocks the Ca + + channels. Symptoms are divided into: + Prodromos (Early symptoms of the disease): "Blurred vision. Dizziness. "Difficulty swallowing and sore throat (diplopia). " Ptosis palpebral. + Late Symptoms: Dyslalia. "Striated muscle paralysis. "Smooth muscle paralysis: bladder retention, paralytic ileus, constipationLie. B. cholinesterase reduction or absence

- Génetico. It is asymptomatic, except when giving succinylcholine or anesthetics. -Acquired by: "MAO inhibitor poisoning. Hepatopathies. C. postsynaptic disorder due to failure of recipients of Oh. -Toxic blocking receptors (curare, etc). -Myasthenia gravis. It is an autoimmune disease (in 95% there is autoAcIn which Ac are produced that bind to the receptors of OhBy blocking them. They are usually associated with thymus hyperplasia (75% hyperplasia, Thymoma 10%). The symptoms are: " Ptosis. " Diplopia. " Disatria, dysphagia, Dysphonia. "Proximal muscles paralysis. Smooth muscle and tenderness are not affected. The Osteotendon reflexes are retained. It only affects skeletal muscle (yes, anyone), and can appear at any age. II. Abnormalities of the excitability of muscle MB Myotonic syndromes. The miotonía is the qualitative alteration Of muscle contraction, by which a persistent contraction appears after the voluntary. It is due to an alteration of the fatty acids of the fosfolípifos In the mb, by which this is made impervious to Cl-. Therefore, the mb It is unstable and late potentials arise that delay muscle relaxation. that is; The mb It hiperexcitable, not enough to unload spontaneously, but to prolong a depolariOrganization Induced. -Disease of Steinert (Myomyotonic dystrophy). is an Enfermedad genétiCA autosomal dominant by alteration in a gene of chromosome 19 Q. Appears at 15-30 years and is characterized by: + Bird face. + Alopecia frontal. + Protusión frontal. + Ptosis. + Sharpening arms and legs. + Miotonía. + Waterfalls. + sterility.

+ Cardiomyopathy. + Mental retardation. -Thomsen's myopathy. Autosomal dominant. Appears from birth, although it is milder than the Steinert: + No mental retardation or cardiomyopathy. + Miotonía General. They fall to the ground, they can't hold an object. + stiffness that is accentuated with rest and cold. + muscular hypertrophy (Herculean appearance), but they are weak -Becker myopathy. Autosomal recessive. It's the same as Thomsen's, but it's different because: + Late appearance. + More frequent. + More serious. - Paramiopatía Congenital, appearing alone in the cold. - Miotonía condrodistrófica. Autosomal recessive. It appears in childhood. It is characterized by: + muscular atrophy. + Stunted growth. + Skeletal deformity. Familial periodic paralysis. Very rare pictures of Character Hereditary. They are due to alterations of the channels and pumps involved in the process of depolarización/repolarization, particularly the pump Na+/K +. Because of this, there is alteredIn the K + and the mb is made temporarily inexcitable, which is why severe weakness in limbs and trunk appears. There are several ways with Normo, hyper or hypokalemia. c) Diskaliemias. are alterations acquired in the concentration of K + (Hyper e hypokalemia). In both there is a decrease in the excitability of the mb. d) tetany. It is produced by the decrease of the Ca + + serum (and Also of the Mg + +), which produces a hiperexcitabilidad In the mb Muscle and nerve (miógeno and neurogenic). As consequentialoccur, there are contrac-Sustained muscle conditions that manifest as: + Hand in Comadrón. + Signs of Trouseau And Chvostek. III. Contractile protein disorders: Muscular dystrophies Muscular dystrophies are genetic diseases (primary) that produce a progressive degeneration of muscle fibers, with consequent atrophy.

Duchenne's progressive muscular dystrophy. is a disorder Linked to the cr X by a failure of the dystrophin gene, a protein related to the mb. This failure facilitates the entry of Ca + + into the muscular fiber, which activates proteases that destroy it. It is manifested as: -Atrophy of the pelvic waist muscles and Proximal legs. As a consequence: "March of" Duck "or" King of comedy ", with hiperlordoLumbar sis and swagger when walking. "Sign of Gowers: When trying to stand up, Supports your hands on your legs and joins climbingAbout themselves. "Tendon and muscular contracture (" cords at the ankles "). " Seudohipertrofia of the calf. -Atrophy of the shoulder girdle muscles and Next of the arms. As a result, they cannot raise their arms above their heads. -Some mental retardation. Cardiomyopathy. - Cifoescoliosis. -Death ends up coming from insufficiency breathe Marriage The heart rate. -Elevation of the serum CPK, which is released by the Destruction of muscle fibers. This tb It happens in women carriers. Becket muscular dystrophy. Qualitative alteration of the Dystrophin. It is a milder form, without mental retardation or CardiomiopaAunt. It appears from the age of 11 and can survive until 50. c) Muscular dystrophy facioescapulohumeral. d) Muscular dystrophy of the waists. e) Dystrophy oculofaríngea. It appears at 50-60 years old, with ptosis and dysphagia due to failure in the nn cricofaríngeo. In the long run, risk of achalasia and breathing. IV. Inflammatory myopathies A) of known cause: Infectious " Virus (p.e VIH)

Bacteriap.e. Staphylococcus, Streptococcus, ClostriDium) FungiCandida, Aspergillus) " Parásitos (Triquina, Toxoplasma) -Non-infectious (drugs) b) of unknown Cause: - Poliomiositis. It is an inflammation (myositis) of origin Autoimmune and predominance lymphocyte. In 1/3 it is associated with other connective diseases (LED, scleroderma, reumatoi arthritisDE). Dermatomyositis. Similar to the previous, but in addition to the Myositis is skin condition: + Sign of Bottom (erythematous papules) + Heliotrope (edema Purplish In neckline). Both diseases are classified as: -Type 1 > primary polymyositis. -Type 2 > primary dermatomyositis. -Type 3 > P or D associated with neoplasia. -Type 4 > P or D infantile associated with systemic vasculitis -Type 5 > P or D associated with enf. of vascular collagen The Dx of both is done: + Clinic: "Proximal muscular weakness even to do routine things like combing. Myalgias. + Biochemistry: Elevation of: " CPK " Aldolasa. " LDH Transaminases. + ECM Alteration + biopsy. -Myositis of inclusion bodies. It is characterized by altering tions In the cytoplasm of the Affected cells (VacuoThe Basophilic next to inclusions eosinófilas). is an inflammationNot responding to the Tto On steroids.

V. Disorders in the release of energy Glycogenosis. Glycogen cannot be degraded, and therefore lack of glucose to obtain energy: + Type II (Pump) + Type V (McArdle) + Type VII (Tarui) -Carnitine and carnitine defect-palmitil-transferase, which are two proteins involved in the entrance of the FFA into the mitochondria to be oxidized. When they fail, fatty acids cannot enter the mitochondria and cannot be used as a source of energy. -Failures in mitochondria, which do not perform oxidative phosphorylation correctly. All these disorders are characterized by: + Premature depletion of the muscle contractile capacity when subjected to intense exercise. + contractures: After exercising the muscles for a while, They keep contracted for lack of energy to put the Ca + + into the REL. These pathological contractions are not accompanied by electrical activity, and are the basis of rigor mortis. + BQ Tests: In glycogenosis does not increase lactate in the blood because glucose is not used. + biopsy. Substrates that can not be used (glucóge No, lipids) accumulate in the cell. Tb can be seen MitoconChanged Drias. VI. Miscellaneous Muscle disorders appear in the following situations: Endocrine. -Malnutrition, due to AA deficiency. Myoglobinuria. It is the emission of red urine because it is dyed with Mb. This is released into the blood by destroying muscle fibers by: + Trauma (crushing syndrome) + Ischemic Necrosis. + Toxic as alcohol. + Metabolic (glycog...