HCR 240 Musculoskeletal System PDF

HCR 240 Week 6 – The Musculoskeletal System Lecturer: Farzana Sarder, MS, PA-C  Test Taking Skills If you received less than 70% on the exam, you are required to contact me for office hours o We will revisit any topics that you may need to study further and discuss t...

HCR 240 Week 6 – The Musculoskeletal System Lecturer: Farzana Sarder, MS, PA-C  Test Taking Skills If you received less than 70% on the exam, you are required to contact me for office hours o We will revisit any topics that you may need to study further and discuss test-taking strategies o Do not feel discouraged by low test scores Ø Get extra help by meeting with tutors, advisors, and instructors Ø Study together with classmates Ø Ask yourself what worked and what did not work Ø Remember that it takes time to develop strong test taking skills  Assigned Reading Read the following chapters in the textbook: Chapter 44: The Musculoskeletal System Chapter 45: Alterations of the Musculoskeletal System Chapter 46: Alterations of the Musculoskeletal System in Children McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Basics of the Musculoskeletal System  Musculoskeletal System The musculoskeletal system is composed of two main parts: Soft tissues Bones and joints (muscles, tendons, ligaments) McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Bones Bones are flexible but hard structures made up of bone matrix (collagen fibers and ground substance) The major inorganic components of bone are calcium and phosphate Bone cells create, maintain, and remodel the bone matrix o Osteoblasts: Bone-forming cells; lay down new bone and later mature into osteocytes o Osteocytes: Maintain bone matrix o Osteoclasts: Bone-remodeling cells McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Bone Anatomy Review bone anatomy: Epiphyseal Long Bone Cross Section growth plate during adolescence McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Bone Healing Process Bone repair occurs during injuries such as fractures. Stages: 1. Hematoma formation: fibrin and platelets form a framework for healing 2. Procallus formation: Fibroblasts and osteoblasts create a granulation tissue called procallus 3. Callus formation: Procallus is hardened by increasing phosphate and calcium deposition 4. Replacement: Callus is replaced with lamellar or trabecular bone 5. Remodeling: Bone remodeled to shape and size prior to injury McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Joints Joints help provide stability and mobility synovial joint to the skeleton. Three types of joints: Fibrous: Bone is directly connected to bone by fibers (no movement) Cartilaginous: Bone is connected via cartilage (allow for shock absorbance and some movement) Synovial: Bone is connect via synovial membrane (most movement) McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Soft Tissues Ligament: tissue connecting bone to bone Tendon: tissue connecting muscle to bone Muscles: Skeletal muscle (voluntary) o Striated Smooth muscle (non-voluntary) o Non-striated McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Alterations of the Musculoskeletal System  Musculoskeletal Injuries Most musculoskeletal injuries occur due to… __________________ Leading cause of death between ages 1 - 44 years of age regardless of socioeconomic status or race ________ can cause injuries to the muscles, bones, and joints of the body. ________: break in continuity of a bone; occurs when force is applied that exceeds the tensile or compressive strength of the bone. McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Classification Fractures can be classified in multiple different ways. Open vs closed: is there a break in the skin that exposes the bone? McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Classification Complete vs incomplete: is the bone broken into multiple different pieces or is it still intact? Displaced: Complete fracture in which two different pieces of the bone no longer line up Comminuted: Complete fracture with bone broken into more than two pieces McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Classification Directionality: Which way does the fracture line go? o Transverse: Fracture line goes straight across the bone o Linear: Fracture line is parallel to long axis of the bone o Oblique: Fracture line is slanted across the shaft of the bone o Spiral: Fracture line encircles the bone From left to right: Transverse, linear, oblique, and spiral fractures McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Classification Fractures can also be named after their etiology Stress fractures: Cumulated affects of repeated forces over time Common in athletes Pathologic fractures: Disease process weakens bone and causes fracture Tumors, infections, osteoporosis, etc McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Fracture Classification How would you describe this fracture? https://radiopaedia.org/cases/tibial-midshaft-fracture?lang=us Fracture Classification 19 y/o male track and field athlete comes into the office with complaints of acute on chronic lateral foot pain. No history of trauma. How would you describe this fracture? https://radiopaedia.org/cases/tibial-midshaft-fracture?lang=us  Fracture Symptoms Clinical manifestations of fractures: o Pain, swelling, immobility, unnatural alignment o Impaired sensation (if injury to nerves) o Impaired blood flow to distal limbs (if injury to blood vessels) Bone fractures can cause injury to nearby blood vessels and nerves. McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Treatment Treatment of fractures: Depends on type of fracture and individual May consist of: o Reduction (realignment of bone fragments; may be open vs closed) Ø Traction: closed external reduction using weights, typically used pre-operatively o Fixation (immobilization of bone; may be be internal vs external) Ø Splints, casts, or other devices McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Fracture Treatment Examples of traction – the use of weights to reduce bone fractures into proper alignment. Typically only used for a short time if the patient is delayed to go to surgery due to medical reasons. https://surgeryreference.aofoundation.org/orthopedic-trauma/adult-trauma/femoral- shaft/wedge-intact-middle-1-3-fractures/nonoperative-treatment-with-limited-resources  Fracture Treatment If bones are able to heal on their own, then why are fractures a problem? May cause injury to nearby blood vessels or nerves May heal incorrectly Improper immobilization or reduction may result in: Nonunion: Failure of bones to grow back together Delayed union: Reunion of bone is delayed to 8-9 months after injury Malunion: Bone heals non-anatomically Treatment Nonunion or delayed union: stimulate bone healing Malunion: will typically need surgical repair McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Strain and Sprain Strain: Sprain: Injury or tear to Injury or tear to tendon (muscle-bone) ligament (bone- bone) You will need to read more about these in the textbook for homework McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Strain and Sprain Clinical manifestations: Pain, functional limitations and weakness, swelling, discoloration Healing tendon and ligament lacks the strength to withstand a strong pull for 4-5 weeks Treatment: Depends on severity - Protect involved structures via immobilization, early rehabilitation when safe, may need surgery if complete rupture McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Rhabdomyolysis Life-threatening complication of severe trauma to striated muscles and subsequent cell lysis o Seen in crush injuries, compartment syndrome, prolonged falls, etc Rapid breakdown of striated muscle cells causes the release of intracellular protein myoglobin o Myoglobin contains a heme structure and is able to store oxygen in muscle cells for heavy exercise o Myoglobin enters the blood stream where it travels to the kidneys, precipitates, and causes acute kidney injury Classic triad: Pain, weakness, and dark-colored urine (looks like blood but no presence of RBCs) Treatment: rapid hydration to prevent kidney injury; dialysis may be necessary McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Rhabdomyolysis Image from Serum myoglobin immunoassays: obsolete or still clinically useful? by Giuseppe Lippi  Osteoporosis Translated to “porous bone” Low bone mineral density, impaired structural integrity, decreased bone strength, increased risk of fracture McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteoporosis Bone is always being reabsorbed (removed) and mineralized (created) o Process controlled by osteoclasts and osteoblasts and regulated by hormones o Peak bone mass is achieved at the age of 30, after which bone reabsorption starts to exceed bone mineralization o Reabsorption increases post-menopause Even though this is a normal process, it becomes a disease when bone mineral density becomes too low o Osteopenia: bone mineral density is less than normal but not yet severe enough for osteoporosis o Osteoporosis: bone mineral density is severely low McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteoporosis Potential causes may include: o Decreased estrogen and testosterone, decreased activity levels, inadequate vitamin D and calcium, certain medications (steroids or glucocorticoids) Clinical manifestations: o Pain, bone deformities, fractures, kyphosis, diminishing height Prevention: o Regular moderate weight-bearing exercise o Sufficient calcium and vitamin D intake during adolescence o Sufficient magnesium Treatment: o Selective estrogen receptor modulators (SERMs), bisphosphonates, denosumab, teriparatide McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteomyelitis Bone infection Most common agent is Staphylococcus aureus Inoculation may be from external penetrating wound, from existing infection, or from blood (sepsis) Infection spreads under the periosteum and along the bone shaft or bone marrow McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteomyelitis Clinical manifestations o Signs and symptoms of inflammation over a localized area (pain, redness, loss of function, increased temperature) o Systemic symptoms (fever, elevated WBC) o May see necrotic bone tissue on imaging Treatment: o Surgical debridement, antibiotics McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteoarthritis Also called degenerative joint disease Common age-related disorder of synovial joints o Incidence increases with increasing age Characterized by local loss of articular cartilage, sclerosis of underlying bone, and the formation of bone spurs in affected joint Clinical manifestations: o Pain, stiffness, enlargement, deformity, and limited mobility of affected joint o Joint swelling (Herberden and Bouchard nodes) o Symptoms are localized - no systemic manifestations McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Osteoarthritis McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Osteoarthritis Treatment: Rest until joint inflammation subsides Range of motion exercises Weight loss Balanced diet Analgesics and over the counter anti-inflammatory medications Supportive therapy: PT/OT, alternative therapies (acupuncture) If more severe: intraarticular injections of hyaluronic acid or surgical joint replacement McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Rheumatoid Arthritis Systemic autoimmune destruction of synovial membrane and joints o Autoantibodies against joints (rheumatoid factor or anticyclic citrullinated peptide antibodies) o Joint fluid fills with exudate, may get rupture of synovial joint McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Rheumatoid Arthritis Clinical manifestations: Painful stiff joints Symmetrical joint swelling Severe joint deformities Systemic manifestations: can affect organs, leading to organ damage McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Rheumatoid Arthritis Treatment: Disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate (first line), azathioprine, sulfasalazine, hydroxychloroquine, leflunomide, and cyclosporine Anti-inflammatory drugs, systemic steroids, steroid joint injections Supportive therapy (PT/OT) Joint replacement surgery if more severe McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Question: What is the difference between osteoarthritis and rheumatoid arthritis? McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Ankylosing Spondylitis Chronic autoimmune inflammatory joint disease of the spine or sacroiliac joints, causing stiffening and fusion of the joints Unknown cause but strong association with human leukocyte antigen B27 (HLA- B27) Tends to affect the axial skeletal, especially the spine “Bamboo spine” McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Ankylosing Spondylitis Clinical manifestations include: Low back pain, stiffness, pain, and restricted motion, Loss of normal lumbar curvature (“bamboo spine”) Kyphosis (outward curvature of cervical spine) Chest pain/restricted chest movement Fibrotic changes to organs Treatment: Supportive therapy (PT/OT) Support groups Nonsteroidal anti-inflammatory drugs, pain medications Local steroid injections to affected joint McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Gouty Arthritis Metabolic disorder of the body caused by high concentrations of uric acid o May be due to either overproduction of or inability to excrete uric acid o Uric acid is created from purine metabolism, which may be formed in the body or obtained from a high purine diet o Uric acid is then secreted from the kidneys (urine) or intestines (stool) McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Gouty Arthritis Build up of uric acid concentration leads to crystallization and deposition in connective tissues o Causes acute pain and inflammation of joints o Can be deposited in cartilage, tendons, soft tissues with visible white nodules (tophi) Other signs/symptoms: o Typically affects the great toe o Pain is usually worse at night o Recurrent attack of the same joint Treatment o Weight reduction, dietary changes (avoidance of alcohol, shellfish, and other foods high in purine), pharmaceuticals McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Gouty Arthritis McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Pediatric Issues McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Scoliosis Caused by vertebral rotation (rotational curvature of the spine) Treatment depends on degree of vertebral rotation o Thoracolumbar bracing if curvature of the spine is 25-40 degrees Ø Bracing will not fix the curvature but will instead prevent further progression Surgical treatment if curvature is greater than 40-50 degrees McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Pediatric Fractures Bowing fracture: Occurs almost exclusively in children Most common mechanism is falling on outstretched hand causing radial and ulnar bowing fractures Thinner cortex of pediatric bones allows for greater elasticity and “bowing” upon force; if force exceeds bone strength then microfractures occur and bone remains in “bowing” position No visible fractures on x-ray, but bone is unusually bent McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Pediatric Fractures Greenstick fracture Bowing fracture with a visible fracture line Fracture is incomplete Typically occurs in children 10 years or younger McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Pediatric Fractures Epiphyseal plate fracture May interrupt normal bone growth if not treated properly Salter Harris Classification of Growth Plate Fractures McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Cerebral Palsy Group of nonprogressive movement and posture disorders caused by injury or malformation of developing central nervous system Signs and symptoms vary widely and may include o Spastic gait o Hemiplegia, diplegia, quadriplegia o Motor milestones are not met on physical exams o Comorbid conditions: seizures, intellectual disability, speech and language disorders Treatment o No cure, need multidisciplinary approach for supportive therapy o Physical and occupational therapies, orthotics o Spasticity reduction with pharmaceuticals (baclofen; botox injections) McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Duchenne Muscular Dystrophy Most common muscular dystrophy X-linked recessive inheritance (affects predominantly males while females are carriers) o Deletion of exons of DMD gene on the X chromosome or a nonsense mutation resulting in termination of translation o Encodes for the dystrophin protein which mediates the anchorage of skeletal muscle fibers to the basement membrane o Poorly anchored fibers tear apart under the repeated stress of contraction; free calcium then enters the muscle cells, causing cell death and fiber necrosis McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Duchenne Muscular Dystrophy Clinical manifestations typically appear by 3 or 4 years of age Gower sign: Using hands to support legs when getting up Gait abnormalities (waddling gait) Progressive muscle weakness Progressive respiratory insufficiency Cardiomyopathy Scoliosis Cognitive dysfunction McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Duchenne Muscular Dystrophy Treatment may include: Supportive care with multidisciplinary approach PT/OT with range-of-motion exercises, bracing Surgical release of contracture deformities Genetic counseling Prognosis: Most people can live to 30 years of age and some may reach 50s. McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Bone Tumors – Ewing Sarcoma Malignant round cell tumor of bone and soft tissue Most lethal malignant bone tumor that can occur during childhood (10-20 years of age) Occurs in the diaphysis of the long bones or in flat bones. Clinical manifestations o Pain, soft tissue mass, fever, malaise, anorexia o “Great imitator” – may look like infection or benign lesions on imaging Treatment o Preoperative chemotherapy to shrink tumor size followed by radiation or surgical resection (or both) with continuation of chemotherapy for 12–18 months o Clinical trials for targeted immunotherapy McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier. Bone Tumors – Ewing Sarcoma McCance, K.L. & Huether, S.E. (2019). Pathophysiology: The biologic basis for disease in adults and children (8th ed). Elsevier.  Questions? Read Chapter 44:The Musculoskeletal System Read Chapter 45: Alterations in the Musculoskeletal System Read Chapter 46: Alterations in the Musculoskeletal System in Children for more details.  Assignments See assignments in Canvas Week 6 Worksheet You will need to use the book and complete the assigned readings