Diseases of Bone PDF

Chapter 43: Disorders of the Skeletal System: Trauma, Infections, Neoplasms, & Childhood Disorders Chapter 44: Disorders of the Skeletal System: Metabolic & Rheumatic Disorders  Fracture: any discontinuity...

Chapter 43: Disorders of the Skeletal System: Trauma, Infections, Neoplasms, & Childhood Disorders Chapter 44: Disorders of the Skeletal System: Metabolic & Rheumatic Disorders  Fracture: any discontinuity of the bone Most common fracture sites. hand, clavicle , humerus ↳ ppl fall , extend arms, pursing endire body weight on arms Activities where fractures can occur ↳ Rollerblading , ice shating · falling from these activities can result in fracture of wrise Fractures common : femur , pervis among elderly Vertebral fracture. Common in those doing a lot of physical intensive jobs Not well fed ppl : Osteoporosis common 114 Compact Bone · bone inward to outward grows · bone breaks outward to inward for bone ? Why is exercise good Whenyoustretchthe periosteum,itpromota b bone cells · osteon fundamental unit of a long or bone compact outwards · Cylinder, go periosteum medullary · external Osteoblasts layer usually of the bone below it that holds blood cavity external surface of bone endosteum Haversian canals compact bone Volkmann’s (contain blood + lymphatic vessels and nerves) inflammation here = blood cut off (can cause necrosis (perforating) canal supply · of bone) Osteon (Haversian System) lamella osteocyte in a lacuna HC canaliculi  Requirements for normal bone density Bone discuse 2 I cat protein / rit mineral r/ + matrix itself (protein) intercellular matrix (e g to osteoblastsf r build intracellular matrix Dietary brought 61 tracts : amino acids · proteins absorbed by our. calcium salts (crystals) confer hardness calcium carbonate calcium phosphate without crystallization, bone hardness does not occur  · ① Need protein (collagen) En have intracellular matrix (ICM) ② Wi ICM , you start to have deposit of the calcium carbonate + phosphate ↳ these deposits make bone stronger ③ Vitamins needed; C e production of connective tissue, D For absorbing more calcium · Osteoblast make bones · Osteoclast : break bone  Requirements for normal bone density Hormones estrogens & testosterone ~ gonna not aveona decrease osteoclast sensitivity to PTH calcitonin vitamins C & D to · wh menopause en estrogen, Osteoclast des estrogen morejensitivity Physical activity stimulates osteoblast  Osteopenia Costeoblast) Losteoclast) Imbalance between bone formation & breakdown. bone formed , broken down ↳a less more Decreased mineralization. contributes ⑨ to all bone diseases Normal formation & breakdown are balanced to: – Replace damaged bone – Maintain the amount and density of bone · Most common bone disease nutrition · seen commonly in post menopausal women + ppl not getting enough  Osteoporosis Disease of reduced bone density predisposes to fractures, especially of the hip and vertebra most common metabolic disease in women (estrogen lus drop) · very common in everly Bone · bone synthesis less than synthesis reabsorption Bone Bone synthesis resorption Bone resorption ↑  Complications of Osteoporosis Spine fractures kyphosis scoliosis [Compression fractures)  Complications of Osteoporosis Hip fractures & nech of femur rit: Otherosclerosis of femor arteries (dec blood supply causing weather bones  Dual Energy X-ray Absorptiometry (DEXA) The most widely used screening tool for measuring bone density is the DEXA DEXA is also useful for monitoring the effects of various medications used to treat osteoporosis  Osteoporosis  Non Pharmacological  exercise  increased dietary intake of calcium ·  decreased dietary intake of phosphates  vit D supplements  smoking cessation  Osteoporosis Pharmacolocical Bisophosphonates – inhibit bone resorption – alendronate, zoledronic acid rh-PTH – stimulates bone remodeling selective estrogen receptor modulator (SERM) – acts on specific estrogen receptors – Raloxifene · Calcitonin – endogenous peptide – partially inhibits osteoclastic activity RANKL inhibitor denosumab – s/c q 6 months – suppress bone resorption & secondary bone formation reu  Osteo-malacia Inadequate mineralization of bone osteoid (soft bone) Deficiencies of Vitamin D d/t decreased: dietary intake intestinal uptake (fat soluble) renal tubular disease vitD) (getting rid of too much bile · Need : Amylase , lipids , protease + vitamins L Pancreatic or liver issues - not absorbing  · Osteomalacia  vitamin D  intestinal uptake of Ca++  serum Ca++  PTH secretion  PTH secretion  osteoclast activity  serum Ca++ i  Ca++ reabsorption by the kidney  PO4-3  mineralization Osteomalacia  Paget’s Disease neoplasm of bone increased bone remodeling (resorption & formation) bone enlarges & softens affects skull, vertebrae, sacrum, sternum, pelvis, femur patch become porous * Hallmark sign : Cotton wool seen of Osteoporosis (bones · as opposite lots of ↳ WI PD , neoplasm of Osteoblasts a multiplying rapidlybones , laid down , the bone tissue being enlarging to mineralize is so fast bones are unable ↳ be process , weah beginning + ad at same rate , becoming usoft time bone becomes mineralized , · After some thich massive + hard it becomes very , Pathology  Pathology Note the thickness of the cranial bones “cotton wool” patch Moderate Advanced  Pathophysiology usually asymptomatic early the course brain compression may cause altered cognitive function & dementia compression of cranial nerves may cause sensory & motor changes stress fractures may occur may begin · bone to bend dit how strong it becomes it doesnt need to · Osteoblasts lay down bone issue where go  Osteomyelitis Bacterial infection of bone (marrow t bone itsalf) usually Staphylococcus aureus endogenous = spread from another site of infection in blood (ear, skin, sinus, teeth) exogenous = from without (open wound, compound #, bite, surgery)  Osteomyelitis Inflammation  vessels thrombose exudate fills canaliculi, Haversion & Volkmann’s canals exudate causes periosteal separation, disrupting blood supply  necrosis of underlying bone ↳ dit infection that blocks Haversion Canal blocking blood supply sequestrum formation ,  Complications weakens bone, spreads to joints causes delayed healing of fractures focus of infection causing septicemia · Bone destruction  Complications Delayed wound healing Bone destruction  Osteo-necrosis (bones not getting enough blook supply) hypoxia > ischemic - - > necrosis Caused by ischemia to bone d/t: Bone fracture Thrombosis or embolism Vessel injury Compartment syndrome inside bone (increased intraosseous pressure) Steroid therapy Bone tumors  Benign Bone Tumors Chondroma - hyaline cartilage Climited growth potential , not very aggressive – Endo-chondroma, sub-periosteal/juxta- cortical chondroma Osteo-chondroma/exostosis—cartilage-capped tumor with bony stalk Lusually abnormal growth forming on adolescence) surface of bone near growth Lepiphyseal plate When child · der curing grows plate , will childhood harden + turn or into solid hole If it’s outgrowth of the growth plate (made of bone AND cartilage) then when child grows the osteochondroma will grow lqrger Osteo-clastoma / giant cell tumors - Can grow single or multiple tumors mononuclear & osteoclast-type giant cells; behave like malignant tumors Found predominantly in the end of the long bones in the mini region + wrist, knee and pelvis Named after osteoclast even tho it’s not class of it (the multi nucleated cell found in this tumor they simply resemble osteoclast) Usually found in women 20-40 Relatively rare, painful when happen, small % of these tumors can spread to other areas Osteosarcoma : most common , found of jaw , shoulder , femur , hip + knee Chondrosarcoma : kids Ewing malignant seen surcoma , among consideration: dull in femur ↳ Nursing young person wi pain knee or - PpI wI bone cancer go through lots of paina give pain mess ↑Bone scan showing popcorn pattern Im of Cancer sign  Malignant Bone Tumors Osteosarcoma – Most common primary malignant bone tumor among addescent – Tends to appear in areas with fastest bone growth ↳ of femur knee or proximal end · 75 %, cases before 20 · Even after ampuration , cancer tends to metastasize to lungs ; femur needs to be amputated Chondrosarcoma: Malignant tumor of cartilage forming cells (Chondrocyte Ewing sarcoma From mesenchymal stem cell ; Common in teens + young adults (more common in maler ; mix = 2 : 1) · Rare , found in bone or soft tissue · Affects : pelvis , femur , humerus , ribs , clavicle · Most times theres a sort of generic connection (tranlocation blW chromo 11 + 22)a Good to look of family he Metastatic bone disease – Most common malignancies found in bone  Variations in Growth & Development Angular and torsional deformities – Intoeing & outtoeing – Internal & external femoral torsion – Internal & external tibial torsion Genu varum & genu valgum knock knees ; AppearanceGre bo reventing ossification of bones , hid improperya se - together at an angle  Congenital Disorders Osteogenesis imperfecta—brittle bone disease from mutation in the collagen gene Failure of - to ossify - soft bones , sheletal deformity These deficiency type alt I born defective connective tissue or ability to make it collagen pr usually · wo w La Most cases caused by this · DX confirmed WI DNA test to see if genetic variation or not · No cure , to aimed at preventing symptoms I delaying deformity cause must first Child+ Females , family he among · unknown common Developmental dysplasia of the hip , Congenital clubfoot (Congenital feel combo ; baby womb or generic t e a l deforming ; when dev in mothers uni or bilateral rolated internally a antile cause not to position ↑ bullmayslipoa Juvenile Osteo-chondroses Osteonecrotic – Local degeneration of the apo-physeal or epiphyseal center (found along spine together tissue where I or more bones come I encapsulated wh connective – Legg-Calvé-Perthes disease - necrosis of femoral head · Affects: hip , femur , pervis ball · Blood supply interrupted to part of hip t bone begins to die I break off easily · Not really Abnormal ossification of cartilaginous tissue – Osgood-Schlatter disease - inflammation of area just below the knee Where tendon from the kneecap (patellar tendon) , attaches to tibic Usually during growth spurt · occurs · Also it stress on bones + muscles if childs athletic be tendons might be dang · Tx: Over the counter meds for pain , rest  Scoliosis Misaligned · curvature minor curvatures Usually · Cause: structural issues posture , · issues rit neuromuscular , congenital be ↳n 155ues this severe need to fixed via surgery  Arthritis “Joint inflammation” · Umbrella term  Osteoarthritis common sites: ↓ Weight-bearing areas hip, knee, hands, spine · Most commun form of arthritis  pathophysiology “wear and tear” articular cartilage erosion sclerosis of underlying bone formation of osteophytes synovitis joint fusion may occur After epiphyseal plate / cartilage dmy Osteoblasts think · , Fracture down bone tissue to connect has occurred and stars to lay these two bones - Want be able to bend certain areas if this occurs Le g: Femur. , tibula + fibula becoming one bone , cand bend leg) ↳ med term Ankylosing is Area ostified wl bone dmy · = ↳ leads to inflammation of joing , joint Fusion  Reactive Arthritis Sterile joint inflammations caused by previous GI infection or STI – Salmonella, Shigella, Campylobacter, Yersinia, Chlamydia Joints not infected at the time of inflammation Reiter syndrome—arthritis, nongonococcal urethritis or cervicitis, and conjunctivitis Entero-pathic arthritis—associated with inflammatory bowel disease or enterogenic bacteria  Psoriatic Arthritis Seronegative inflammatory arthropathy Oligoarticular form—four or fewer joints Spondylitis form—sacroiliitis, spinal involvement Polyarticular/symmetric form—resembles RA Distal interphalangeal joint form Arthritis mutilans—very destructive · Don't memorize  Rheumatoid Arthritis most commonly affects: hands (MCP, · most common i n hands PIP joints), wrists, elbows, hips, ankles, knees, shoulders, hips, spine affected only weight bearing oste cause: where , unlike are · all joints autoimmune disease (Rh factors) inflammation of synovial membrane articular cartilage, joint capsule, ligaments, tendons  Pathophysiology microbes may precipitate the auto- immunne response RF activates complement synovitis joint capsule, ligaments, tendons pannus formation of synovium PMNs & macrophages release enzymes degrading synovium & articular cartilage L lots of macrophages invade tissue + spill own enzymes  Complications joints become swollen, painful, stiff loss of mobility muscle atrophy & flexion contractures Ankylosis rheumatoid nodules eyes bu systemic r  Meds for Rheumatoid Arthritis NSAIDs and COX-2 inhibitors Corticosteroids Disease-modifying antirheumatic drugs (DMARDs) – Methotrexate, leflunomide Biologic agents – Infliximab, abatacept, tocilizumab, tofacitinib  Systemic Lupus Erythematosus (SLE) Type III hypersensitivity reaction ( form most common of lupus) Autoantibodies against self molecules in: – Plasma – Cytoplasm – The cell surface – The cell nucleus—antinuclear antibodies (ANA) · Affects heart , joint in lunge , bu , Kidney , liver · Course of disease unpredictable  Arthralgia, arthritis Skin lesions (butterfly rash) Renal involvement (glomerulonephritis) Pleural effusions, pleuritis Cardiovascular disease (pericarditis, coronary heart disease, hypertension) Hematologic disorders CNS and PNS involvement · Joint paint increased creatinine + blood urea nitrogen  Systemic Sclerosis (Scleroderma) Autoimmune disease Fibroblast activation fibrosis throughout body - extensive Extensive fibrosis throughout the body Affects skin & internal organs Limited & diffuse clinical subsets · Hardens Connective tissue  Spondylo-arthropathies Multisystem inflammatory disorders Sacroilitis—pathologic hallmark Inflammation begins at insertions of tendons and ligaments into bone Axial spondyloarthropathies – Ankylosing spondylitis (vertebrae fuse, cane bend down) Peripheral spondyloarthropathies – Reactive arthritis, psoriatic arthritis Ankylosing Spondylitis  Cause disorder of purine metabolism or excretion HYPERURICEMIA uric acid crystalizes in joints & tissues causing inflammation Gouty Arthitis  · Disorder of purine metabolism or excretion - Hyperuricemia · Uric acid crystalizes in joints + tissue > inflammation - · Connected we renal system -I have to bring uric acid levels down  Rheumatic Diseases in Children Juvenile idiopathic arthritis – Category of diseases Oligoarthritis, polyarticular disorder Juvenile spondyloarthropathies – Associated with ulcerative colitis, regional enteritis Juvenile dermatomyositis – Autoimmune disorder – Proximal muscle weakness, rash  Rheumatic Diseases in the Elderly Osteoarthritis Rheumatoid arthritis – RA diagnosed before age 60 – Elderly onset RA (EORA) diagnosed after age 60 Crystal-induced arthropathies – Gout—monosodium urate – Pseudogout—calcium pyrophosphate Polymyalgia rheumatica—can develop giant cell arteritis