Osteomyelitis and Osteoporosis PATH1016 Past Paper PDF

Osteomyelitis and Osteoporosis PATH1016 PATH1016_Osteomyelitis_Osteoporosis 2024-25 1  What is Osteomyelitis Infection in the bone Reaches bone by 2 methods 1. Indirect blood (Hematogenous) 2. Direct – trauma or surgery (Exogenous) Predisposing factor Vascular...

Osteomyelitis and Osteoporosis PATH1016 PATH1016_Osteomyelitis_Osteoporosis 2024-25 1  What is Osteomyelitis Infection in the bone Reaches bone by 2 methods 1. Indirect blood (Hematogenous) 2. Direct – trauma or surgery (Exogenous) Predisposing factor Vascular insufficiency IV drugs Immunodeficiency/Immunosuppression Most common pathogen is Staph Aureus. PATH1016_Osteomyelitis_Osteoporosis 2024-25 2 INDIRECT - Hematogenous Organism reaches the target tissue via blood vessel and attach Bacterial growth =>bone destruction and abscess formation => purulent exudate Minimal swelling Exudate beneath periosteum, shearing blood vessels => necrosis Sequestra (devascularized fragments of bone) PATH1016_Osteomyelitis_Osteoporosis 2024-25 3 Hematogenous Osteomyelitis (A) Infectious organisms reach the metaphysis through a nutrient blood vessel. (B) Bacterial growth results in bone destruction and abscess formation; spreads between the trabeculae into the medullary cavity of compact bone, then through cortex to the outside. (C) Purulent exudate finds its way beneath the periosteum; leads to necrosis of cortical bone and formation of devascularized fragments, called sequestra. (Porth 2020) Fractures & Osteomyelitis Osteomyelitis – click on link above – click on link above PATH1016_Osteomyelitis_Osteoporosis 2024-25 4 Manifestations Signs & symptoms of bacteremia accompanied by symptoms relating to site of bone lesion Pain Fever Loss of movement Tenderness Erythema (over affected bone) Swelling PATH1016_Osteomyelitis_Osteoporosis 2024-25 5 Diagnosis and treatment Diagnosis X-rays may show periosteal elevation Bone scan MRI Blood cultures Bone aspiration culture Treatment Antimicrobials Analgesia Debridement and surgical drainage PATH1016_Osteomyelitis_Osteoporosis 2024-25 6  Generally, occur secondary to an open wound May be due to delayed treatment or inadequate treatment of hematogenous osteomyelitis Chronic Can persist for years Osteomyelitis Hallmark feature Presence of sequestrum that has separated from living bone (McCance et al., 2014) Formation of involucrum around dead bone PATH1016_Osteomyelitis_Osteoporosis 2024-25 7 Chronic Osteomyelitis Diagnosis: X-ray Bone scan Sinograms Wound culture & Sensitivity Treatment: Antimicrobials Surgery to remove sequestra and long-term antibiotics (ABX) Immobilization PATH1016_Osteomyelitis_Osteoporosis 2024-25 8 DIRECT – Trauma and/or Fracture Bacteria introduced right into the bone by penetrating wound or fracture (#) Injury from local inflammation and trauma may devitalize bone Leads to an inert matrix for organism to proliferate PATH1016_Osteomyelitis_Osteoporosis 2024-25 9 Manifestations - Symptoms Recurrent fever Increased pain at trauma/operative site Poor incisional healing Wound drainage Wound separation PATH1016_Osteomyelitis_Osteoporosis 2024-25 10 Treatment Antibiotics May not respond to antibiotics Surgical management Surgical decompression used to release intramedullary pressure and remove drainage PATH1016_Osteomyelitis_Osteoporosis 2024-25 11  Review: Growing Bones ▪ Osteoblasts: (bone forming cells) form new bone cells in a process called remodeling ▪ Osteoclasts: (bone destroying cells) break down calcium and phosphorus in a process called resorption ▪ Osteocytes: maintain bone as a living tissue ▪ Osteopenia: decreased bone density PATH1016_Osteomyelitis_Osteoporosis 2024-25 12 What is Osteoporosis? Decreased bone mass Porous bone, chronic, progressive metabolic disease Can lead to increased risk of fractures Imbalance between bone resorption and formation Predisposing factors Common in elderly women (estrogen deficiency) Elderly (Senile osteoporosis) Elevated cortisol (Cushing’s) Chronic diseases Kidney failure – VitD and Ca+ Prolonged immobilization Poor diet PATH1016_Osteomyelitis_Osteoporosis 2024-25 13 Clinical Features Changes in diaphysis and metaphysis of bone Loss of trabeculae Post menopausal osteoporosis Increase osteoclast activity in bones with large surface area Trabeculae become thinned Leads to microfractures and vertebral collapse Senile osteoporosis Osteoporotic complex is thinned by resorption Haversian systems enlarge Leads to fractures PATH1016_Osteomyelitis_Osteoporosis 2024-25 14  Clinical Features Loss of trabeculae from cancellous bone and thinning of the cortex = fractures https://study.com/cimages/multimages/ 16/photo_spongy_bone.png PATH1016_Osteomyelitis_Osteoporosis 2024-25 15 Manifestations Compression of vertebrae Fractures most people unaware until fracture occurs or until a bone scan is done Development of kyphosis “dowager’s hump” in middle age Decrease in height, back pain PATH1016_Osteomyelitis_Osteoporosis 2024-25 16 Diagnosis BMD assessment Dual-energy x-ray absorptiometry (DEXA) Screening Bone mass density (BMD) determined by Genetic factors Sex Hormone levels Exercise Calcium intake Age related PATH1016_Osteomyelitis_Osteoporosis 2024-25 17 Treatment Treatment = Prevention Vitamin D intake Calcium Weight bearing exercises Medications 1. Bi-phosphonates 2. selective estrogen receptor modulators 3. Calcitonin 4. recombinant PTH PATH1016_Osteomyelitis_Osteoporosis 2024-25 18