pathophysiology exam 4

fracture definition

A fracture is any break in the continuity of bone caused by trauma, overuse, or disease (e.g., osteoporosis, cancer).

closed (simple)

-Bone breaks but skin remains intact

-Least risk of infection

open (compound)

-Bone breaks through skin

-High infection risk (osteomyelitis)

greenstick 

-Incomplete break; bone bends and cracks on one side

-Common in children (flexible bones)

comminuted

-Bone shattered into 3+ fragments

-Severe trauma, may need surgical repair

transverse 

-Break straight across bone shaft (horizontal line)

-Often from direct blow

oblique

-Diagonal break across bone

-Twisting or angled impact

spiral

-Bone twisted apart in a spiral line

-Seen in rotational injuries (child abuse red flag)

impacted

-Ends of bone driven into each other

-Common in falls, especially on outstretched arm

depressed

-Bone pressed inward

-Common in skull fractures

compression

-Bone collapses, often in vertebrae

-Seen in osteoporosis

pathologic

-Occurs due to weakened bone from disease (osteoporosis, cancer)

-Minimal trauma may cause break

stress (hairline)

-Tiny crack from repetitive stress

-Runners, athletes — often tibia or metatarsals

fracture healing stages

1. Hematoma Formation (1–3 days): Bleeding → clot → inflammation.

2. Granulation (3–14 days): Capillaries and fibroblasts form soft tissue bridge.

3. Callus Formation (2–6 weeks): Osteoblasts create soft callus → hard callus.

4. Ossification (3–6 months): Bone becomes stronger and more stable.

5. Remodeling (months–years): Compact bone replaces spongy bone; normal shape restored.

fracture complications

• Infection (osteomyelitis) – especially open fractures.

• Fat embolism syndrome – long bone fractures (femur).

• Compartment syndrome – swelling → ischemia.

• Delayed union / malunion / nonunion – poor healing.

• Avascular necrosis – loss of blood flow (femoral head common).

treatment of fractures

• Reduction: Align bone (closed vs. open).

• Immobilization: Cast, traction, external fixator, ORIF (open reduction internal fixation).

• Rehabilitation: Physical therapy, gradual weight bearing.

• Pain & Infection control: Analgesics, antibiotics (if open).

osteosarcoma

• Teens & young adults (10–25 yrs)

• Long bones (femur, tibia, humerus)

• Most common primary bone cancer; painful enlarging mass; “sunburst” or “Codman’s triangle” on X-ray

Ewing’s sarcoma

• Children & adolescents

• Pelvis, femur, ribs

• Small round blue cells on biopsy; “onion-skin” periosteal reaction; fever & systemic symptoms common

chondrocarcoma

• Middle-aged to older adults

• Pelvis, femur, shoulder

• Arises from cartilage cells; slow-growing; resistant to chemo/radiation

fibrosarcoma /malignant fibrous histiocytoma

• Middle-aged adults

• Long bones, soft tissue

• Local pain/swelling; variable prognosis

multiple myeloma

• Adults >40

• Vertebrae, ribs, skull

• Plasma cell cancer; bone pain, anemia, hypercalcemia; “punched-out” lesions on X-ray

metastatic bone disease

• adults

• Axial skeleton (spine, pelvis, ribs)

• Most common bone malignancy overall; from breast, lung, thyroid, kidney, prostate (“BLT with a Kosher Pickle”)

pathophysiology of bone cancer

• Uncontrolled proliferation of abnormal bone cells → destruction of bone matrix.

• Osteolytic lesions (bone resorption) cause pain, fractures, and hypercalcemia.

• Tumor cells may secrete substances that interfere with bone remodeling.

diagnostics and manifestations of bone cancer

• Deep, persistent bone pain (worse at night, unrelieved by rest).

• Swelling or palpable mass.

• Pathologic fractures.

• Fatigue, weight loss, fever (systemic signs).

• Limited ROM if near joint.

• Imaging:

  • X-ray → characteristic patterns (sunburst, onion-skin, punched-out).

  • MRI/CT → tumor extent.

  • Bone scan → metastases.

• Biopsy: Confirms diagnosis & cell type.

• Lab tests:

  • ↑ Alkaline phosphatase, ↑ calcium (bone destruction).

  • CBC & protein studies for multiple myeloma (M protein, Bence-Jones protein).

osteoporosis

Definition: A metabolic bone disease causing decreased bone density and increased fracture risk.

Pathophysiology:

• Imbalance between bone resorption (↑ osteoclast activity) and bone formation (↓ osteoblast activity).

• Leads to porous, fragile bones.

Risk Factors:

• Aging, postmenopausal women (↓ estrogen), family history, smoking, low calcium/vitamin D, sedentary lifestyle, corticosteroid use.

Clinical Manifestations:

• Silent until fracture occurs (hip, wrist, vertebrae).

• Loss of height, kyphosis (“dowager’s hump”).

Diagnostics:

• DEXA scan (T-score ≤ –2.5 = osteoporosis).

• Serum Ca²⁺, vitamin D, and alkaline phosphatase levels.

Treatment:

• Weight-bearing exercise, calcium + vitamin D, bisphosphonates (alendronate), SERMs, fall prevention.

osteomyelitis

Definition: Infection of bone or bone marrow (commonly by Staphylococcus aureus).

Pathophysiology:

• Bacteria enter bone → inflammation → bone necrosis → abscess → impaired blood flow.

Risk Factors:

• Open fractures, surgery, diabetes, vascular disease, IV drug use.

Manifestations:

• Bone pain, fever, redness, swelling, non-healing ulcers.

Diagnostics:

• Elevated WBC, ESR, CRP, MRI, bone biopsy/culture.

Treatment:

• IV antibiotics (6–8 weeks), possible debridement or amputation.

compartment syndrome

Definition: Increased pressure within a closed muscle compartment → impaired perfusion → ischemia.

Causes: Fractures, crush injuries, tight casts/bandages.

6 Ps: Pain (out of proportion), Pallor, Paresthesia, Paralysis, Pulselessness, Pressure.

Treatment:

• Remove restrictive dressing, fasciotomy (emergency).

osteoarthritis

Definition: Degenerative joint disease from cartilage wear and tear.

Pathophysiology:

• Cartilage erosion → bone-on-bone friction → osteophyte formation.

Risk Factors: Age, obesity, joint overuse, trauma.

Manifestations:

• Joint pain/stiffness (worse with activity), crepitus, asymmetrical involvement.

Treatment:

• NSAIDs, weight loss, joint injections, PT, joint replacement.

sprains, strains, & dislocations

Sprain: Ligament injury.
Strain: Muscle or tendon injury.
Dislocation: Bone displacement from joint.

Treatment (RICE): Rest, Ice, Compression, Elevation + pain control.

gout

Definition: Uric acid crystal accumulation in joints → inflammation.

Risk Factors: High purine diet, alcohol, kidney disease, obesity.

Manifestations: Sudden severe pain (often great toe), redness, swelling.

Treatment:

• Acute: NSAIDs, colchicine.

• Chronic: Allopurinol, dietary modifications.

fibromyalgia

Definition: Chronic widespread musculoskeletal pain with fatigue and tender points. (11/18 tender spots)

Pathophysiology: Abnormal pain perception and neurotransmitter imbalance.

Treatment:

• Exercise, antidepressants (SNRIs, TCAs), anticonvulsants (pregabalin).

ankylosing spondylitis

Definition: Chronic inflammatory arthritis of spine and sacroiliac joints.

Manifestations:

• Morning stiffness, back pain, loss of spinal curvature (“bamboo spine”).

Treatment:

• NSAIDs, biologics (TNF inhibitors), PT.

rheumatoid arthritis

Definition: Autoimmune inflammatory joint disease.

Pathophysiology:

• Synovial inflammation → pannus formation → joint destruction.

Manifestations:

• Symmetrical joint pain, morning stiffness >1 hr, deformities (ulnar drift, swan neck).

Diagnostics:

• ↑ ESR/CRP, RF, anti-CCP antibodies.

Treatment:

• DMARDs (methotrexate), corticosteroids, NSAIDs.

ABG interpretation (acid-base calculations) 

Parameter	Normal Range
pH	7.35–7.45
PaCO₂	35–45 mmHg
HCO₃⁻	22–26 mEq/L

asthma

Definition: Reversible airway obstruction due to inflammation and hyperreactivity.

Manifestations: Wheezing, cough, dyspnea, chest tightness.

Treatment:

• Short-acting bronchodilators (albuterol), corticosteroids, long-acting beta agonists.

pulmonary hypertension

Definition: Elevated pulmonary artery pressure (>25 mmHg).

Causes: COPD, left heart disease, hypoxia, idiopathic.

Manifestations: Dyspnea, fatigue, syncope, RV hypertrophy.

Treatment: Vasodilators, oxygen, diuretics.

respiratory terminology 

• Tidal Volume (TV): Air in/out with normal breath.

• Vital Capacity (VC): Max air exhaled after deep inhale.

• FiO₂: Fraction of inspired oxygen.

• SpO₂: Oxygen saturation (normal 95–100%).

common cold

-rhinovirus

-nasal congestion, sneezing 

-self-limiting

flu

-influenza virus

-fever, body aches, cough

-annual vaccine

pneumonia

-bacterial or viral

-productive cough, fever, crackles

-CXR shows consolidation

tuberculosis TB

-mycobacterium tuberculosis

-night sweats, hemoptysis, weight loss

-airborne isolation

COPD

Includes: Chronic bronchitis + emphysema.
Manifestations:

• Chronic cough, sputum, dyspnea, barrel chest, clubbing.

Treatment:

• Bronchodilators, corticosteroids, oxygen therapy, smoking cessation.

chest complications

• Flail chest: Multiple rib fractures → paradoxical chest movement.

• Pneumothorax: Air in pleural space → lung collapse.

  • Treatment: Chest tube.

• Pleural effusion: Fluid in pleural space → diminished breath sounds.

  • Treatment: Thoracentesis.

epiglottitis 

Definition: Inflammation of epiglottis (often H. influenzae type b).

Emergency Signs: Drooling, dysphagia, distress, tripod position.

Treatment: Airway management, antibiotics (cephalosporins).

acute respiratory distress syndrome ARDS

Pathophysiology:

• Alveolar-capillary membrane damage → fluid leakage → refractory hypoxemia.

Causes: Sepsis, trauma, aspiration.

Treatment:

• Mechanical ventilation (low tidal volume), treat underlying cause.

pulmonary embolism PE 

Definition: Obstruction of pulmonary artery by clot.

Risk Factors: DVT, immobility, surgery, pregnancy.

Symptoms: Sudden dyspnea, chest pain, tachycardia, hypoxia.

Diagnostics: D-dimer, CT angiogram.

Treatment: Anticoagulants (heparin, warfarin), thrombolytics if severe.

cor pulmonale

Definition: Right-sided heart failure secondary to pulmonary disease.

Cause: Chronic hypoxia → pulmonary vasoconstriction → RV hypertrophy.

Manifestations: JVD, peripheral edema, hepatomegaly.

Treatment: Treat underlying lung disease, oxygen therapy, diuretics.

musculoskeletal terms

• Atrophy: Decrease in muscle size.

• Contracture: Permanent muscle shortening.

• Crepitus: Grating sound with joint movement.

• Reduction: Realignment of bone.

• Arthroplasty: Joint replacement surgery.

• Myalgia: Muscle pain