SKELETAL SYSTEM PATHOLOGY

A comprehensive set of QUESTION_AND_ANSWER style flashcards covering common skeletal system pathology topics from the lecture notes.

What is a butterfly vertebra and what is its typical clinical significance?

A congenital vertebral defect that usually has no clinical significance.

What is a cervical rib and what are potential complications?

A supernumerary rib attached to C7; present in about 0.05% of people; usually unilateral; may compress the brachial plexus or subclavian artery and sometimes requires surgical removal.

Osgood-Schlatter disease affects which population and which anatomical site?

Young athletes (ages ~10–16); inflammation of the tibial tuberosity after exercise.

What causes osteogenesis imperfecta and what is a common nickname for the condition?

Deficiency of type I collagen leading to brittle bones; also called brittle bone disease.

What are two severe fetal outcomes associated with osteogenesis imperfecta?

In severe cases, multiple fractures can occur in the fetus; many infants are stillborn or die shortly after birth.

Describe osteopetrosis in terms of bone density and clinical outcome.

Disorder of endochondral ossification with very hard, dense bones (marble bone); bones are brittle and the condition can be fatal at birth or asymptomatic in adulthood; no definitive treatment.

What is the radiographic appearance associated with adult osteopetrosis?

A marbled radiographic appearance indicating a benign form.

What is infantile osteopetrosis?

The lethal form of osteopetrosis occurring in infancy.

Define osteoporosis.

A reduction in bone mass leading to increased fracture risk due to an imbalance between bone destruction and formation.

What are the primary causes of osteoporosis?

Aging and postmenopausal hormonal changes.

What diagnostic method is commonly used to measure bone mineral density?

Dual-energy X-ray absorptiometry (DEXA) scan.

List common fracture sites associated with osteoporosis.

Hip fractures, compression fractures of the vertebral bodies, and Colles’ fractures of the wrist.

What is osteomalacia?

Softening of bones due to insufficient mineralization, often from decreased vitamin D or calcium absorption.

Name two consequences or presentations of osteomalacia.

Bone bowing and possible greenstick fractures; can result from inadequate vitamin D/calcium intake or low sunlight exposure.

What is osteomyelitis and what are two key radiographic features mentioned?

Bacterial bone infection; Brodie’s abscess and sequestrum (an avascular island of bone within an abscess).

What is Brodie’s abscess?

A localized subacute bacterial osteomyelitis abscess within bone.

What is sequestrum in osteomyelitis?

An avascular piece of dead bone ('island') within an abscess.

What are the general treatment considerations for osteomyelitis?

Usually prolonged antibiotic therapy.

What is rheumatoid arthritis (RA) and its basic pathogenesis?

A chronic inflammatory arthritis involving the synovial membranes with pannus formation leading to erosion of cartilage and joints, and eventual ankylosis.

Which gender is RA more common in and what is a classic finger deformity?

More common in women; can cause ulnar deviation of the fingers.

Name two common symptoms and signs of RA.

Morning stiffness and joint pain with ulnar deviation of fingers.

What are typical RA treatments mentioned?

Steroids to reduce inflammation and analgesics (e.g., aspirin) for pain.

Describe ankylosing spondylitis and its characteristic radiographic appearance.

Chronic inflammatory arthritis primarily affecting the sacroiliac joints and spine; causes osteoporosis and fusion, giving a 'bamboo spine' appearance.

What is gout and what causes the symptoms?

Metabolic arthritis due to excess uric acid from purine metabolism, leading to crystal deposition in joints (often the great toe) and inflammatory pain.

Which joints are commonly affected by gout besides the great toe?

Hands and knees.

What is osteoarthritis and its typical radiographic and clinical features?

Most common degenerative joint disease; loss of joint cartilage with formation of bone spurs (osteophytes); presents with joint stiffness and pain that worsens with activity.

How is osteoarthritis typically managed?

Steroids to reduce inflammation, analgesics (aspirin) for pain, and joint replacement surgery in advanced cases.

What is Paget’s disease (osteitis deformans) and where is it commonly seen?

Abnormal bone remodeling with cycles of destruction and excessive growth; commonly seen in the pelvis, lumbar spine, and skull.

Name two signs or complications associated with Paget’s disease.

Bone pain, deformity, arthritis, and fractures.

Define spondylolysis.

A fracture or defect in the pars interarticularis; usually bilateral; results in loss of neural arch continuity, most commonly between L5 and S1.

Differentiate spondylolysis from spondylolisthesis.

Spondylolysis is a pars defect; spondylolisthesis is forward displacement (subluxation) of a vertebral body on the one below it.

What are the four grades of spondylolisthesis and common treatments?

Four grades (I–IV) based on the degree of slippage; treatment includes back braces or surgery.

What does spondylosis refer to?

General degeneration of the spine.

What is spondylitis?

Inflammation of the vertebrae that can lead to arthritis.

What is osteopoikilosis and its typical clinical presentation?

Osteosclerotic bone dysplasia with multiple small radiopaque densities (bone islands); etiology unknown and usually asymptomatic.

Describe bone cysts and their clinical significance.

Common benign, expansile, radiolucent, fluid-filled lesions; more common in males; unknown etiology; may cause pain or pathologic fracture, otherwise typically insignificant.

What are the two general categories of bone tumors and how do they differ radiographically?

Osteolytic tumors (cause bone destruction, lucent appearance) and osteoblastic tumors (increase bone density, opaque appearance).

What is enchondroma and where is it commonly found?

A benign cartilaginous tumor located in bone marrow; most common in hands, feet, and ribs of young adults; radiolucent with calcifications.

Describe osteochondroma and its typical radiographic appearance.

Benign projection of bone with a cartilaginous cap; commonly arises from the metaphysis of long bones, ribs, and pelvis; often has a mushroom or cauliflower appearance.

What is multiple myeloma and its cardinal radiographic findings?

Malignant proliferation of plasma cells; causes multicentric (punched-out) osteolytic lesions; Bence-Jones proteins in urine; marked osteoporosis with vertebral compression fractures.

How is multiple myeloma typically treated given there is no curative therapy?

Suppression and containment with chemotherapy, stem cell treatment, and steroids.

What is osteosarcoma and which age group is most affected?

Second most common malignant bone tumor; osteoblastic; usually affects ages 10–25; around the knee is the most common site; commonly metastasizes to the lungs with poor prognosis.

What is chondrosarcoma and its relative frequency among malignant bone cancers?

An expansile, osteolytic primary malignant bone tumor; accounts for about 10% of malignant skeletal cancers.

Describe fibrosarcoma in the skeletal system.

Osteolytic malignant bone cancer with a moth-eaten radiographic appearance; primary cancer of the skeletal system often affecting the knee and pelvis.

What is secondary bone cancer and its common primary sources?

Most common type of bone malignancy; metastases from prostate, breast, thyroid, colon, and kidneys; seeds to long bones, ribs, and spine; can be osteolytic or osteoblastic.

Define Colles’ fracture.

Transverse fracture of the distal radius with posterior (dorsal) displacement.

Define Smith’s fracture.

Transverse fracture of the distal radius with anterior (volar) displacement.

Describe Bennet’s fracture.

Fracture at the base of the first metacarpal bone.

Describe Boxer's fracture.

Transverse fracture of the fifth metacarpal bone.

Describe Barton’s fracture.

Fracture involving part of the wrist with displacement of another part.

What is a Greenstick fracture?

A fracture where the bone bends and cracks on one side without breaking into multiple pieces.

What is a comminuted fracture?

A fracture in which the bone is broken in at least two places.

What is an open fracture?

A fracture with an open wound or break in the skin near the fracture site.

What is a transverse fracture?

A fracture that runs horizontally, perpendicular to the long axis of the bone.