MSK Pathology

Question 1

Rickets

Answer 1

defective mineralization of cartilage in the growth of platesin CHILDREN…
leads to skeletal deformities

VITAMIN D DEFICIENCY
*calcium deficiency too
*phosphate deficiency

sxs
delayed growth
bone pain or tenderness
skeletal deformities
dental problems
muscle weakness

Question 1

Osteomalacia

Answer 1

impaired mineralization of bone matrix…. softening of bones

sxs
diffuse bone pain, esp in hips
muscle weakness
difficulty walking
bone tenderness
fractures with minimal trauma

WHY?
vitamin d deficiency
impaired phosphate metabolism
certian medications
chronic kidney disease

Question 2

Scurvy

Answer 2

impaired collagen synthesis due to vitamin C deficiency;

leads to weakened connective tissues

VITAMIN C DEFICIENCY
think pirate disease

sxs
fatigue
gum disease
poor wound healing
bruising easily
joint and muscle pain
corkscrew hair

Question 3

Ankylosing Spondylitis

Answer 3

Inflammation of axila skeleten

@SACRO-ILIAC joints

leads to progressive stiffness and fusion of the spine

sxs
chronic back pain and stiffness (esp in morning)
pain impoves with exercise but not rest
peripheral arthritis, uvethtis, and enthesitis

GENETIC LINK: HLA-B27

Question 4

Bursitis

Answer 4

inflammation of bursa
Small fluid filled sacs that cushion bones, tendons and muscles near joints

sxs
localized pain and tenderness
swelling and warmth over bursa
limited range of motion in affected joint

EX: rheumatoid arthritis and gout

Question 5

Fibromylagia

Answer 5

central pain processing leading to widespread pain and heightened pain sensitivity

sxs
msk pain
fatigue
sleep disturbances
cognitive difficulties
multiple tender points

Question 6

Myositis … dermatomyositis, polymyositis

Answer 6

autoimmune inflammation of muscle tissue (polymupsitis) or muscle and skin (dermatomyositis)

sxs
symmetrical proximal muscle weakness
muscle pain and tenderness
skin rash (heliotrope rash, gottron’s papules)
difficulty swallowing and respiratory involvement in severe cases

Question 7

Gout

Answer 7

deposition of monosodium urate crystals in joints and soft tissues due to hyperuricemia

sxs
severe joint pain (usually in first metatarsophalangeal joint)
swelling, reddness and warmth
tophaceous depoisits in chronic gout

… overproduction or underexcretion of uric acid…
- high purine diet (A and Gs… meats and organ meats)
- alcohol consumption, or medications

Question 8

Polymyalgia Rheumatica (PMR)

Answer 8

inflammatory disorder causing muscle pain and stiffness, particularly in shoulders and hips

sxs
bilateral shoulder and hip girdle pain and stiffness
morning stiffness (for more than 30 mins)
systemic symptoms like fever, weight less, and fatigue

Question 9

Reactive Arthritis (Reiters Syndrome)

Answer 9

Inflammatory arthritis triggered by na infection elsewhere in the body

sxs
asymmetric arthritis, involves the lower extremities
conjunctivitis or uveitis
urethritis or cervitits
Enthesitis and dactylitis

… typically follows GI or GU infection like chlamydia, salmonella, shigella

Question 10

classic reactive arthritis triad

Answer 10

conjunctivitis (cant see)
Urethritis (cant pee)
Arthritis (cant bend the knee)

Question 11

Tendonitis

Answer 11

inflammation or irritation of a tendon, leads to pain and tenderness near a joint

sxs
pain and tenderness along tendon

BC: overuse or repeititive motion, acute injurt, age related degeneration

Question 12

Osteopetrosis

Answer 12

defective OSTEOCLAST mediated bone resorption leading to abnormally dense but brittle bones

sxs
bone fractures
cranial nerve compression symptoms (vision or hearing loss)
anemia, thrombocytopenia, and leukopenia because of bone marrow failure
hepatosplenomegaly due to extramedullary hemoatpoiesis

GENETIC: affecting osteoclast function, CLCN7 and TCIRG1

Question 13

Marfan Syndrome

Answer 13

connective tissue disorder due to mutations in the FBN1 gene or …. affecting fibrillin-1

*Autosomal dominant inheritance

sxs
tall stature, long limbs and fingers
oextus excavatum or pextus carinatum
scoliosis
joint hypermobility
CVS manifestations
ocular problems

Question 14

Muscular Dystrophy

Answer 14

progeressive muscle degeneration and weakness due to genetic defects in muscle proteins

sxs
progressive muscle weakness and wasting
delayed motor milestones in children
Gower’s sign (hands to push of ground)
psudohypertrophy in calf muscles
cardiomyopathy and respiratroy failure in advanced stages

GENETIC: DUSCHENNE and BECKER muscular dystrophies

Question 15

Osteogenesis Imperfecta

Answer 15

Defective collagen synthesis leading to brittle bones that fracture easily

sxs
blue sclerae
dental abnormalities
hearing loss
short stature
frequent fractures

GENETIC: COL1A1, COLA1A2… affects type 1 collagen

Question 16

Osteoarthritis OZ / DJD (Degenrative joint disease)

Answer 16

progressive degeneration of articular cartilage with secondary changes in the subchondral bone and synovium

sxs
join pain worsens with activity, improves with rest
morning stiffness more than 30 mins
joint movement
reduced range of motion

Initial trigger???
- small tears
- previous joint injury

Question 17

Osteoporosis

Answer 17

decreased bone density and quality, leading to increased fragility and fracture risk

often asymptomatic until a fracture occues
common fractures sites: hip, spine, wrist
height loss and kyphosis (because of vertebral compression fractures)

*calcium and vitamin D component

Hips, spine, wrist

Question 18

Pagets Disease

Answer 18

Disorganized bone remodeling leading to abnormal bone structure and weakness

**remodeling happens but in a disorganized fashion

sxs
bone pain
bone deformities
enlarged skull
hearing loss
increased warmth over affected bones due to hypervascularity
cardiac failure

WHY: possibly genetic and probably VIRAL

Question 19

Avascular Necrosis

Answer 19

Death of bone tissue due to interrupted blood supply

sxs
pain in affected joint (hip and shoulder)
pain may worsen with weight bearing activities
limited range of motion
progressive joint stiffness

WHY:
FEMORAL HEAD COLLAPSE
OR blood supply to the snuff box // aka scaphoid

Question 20

Chondrosarcoma

Answer 20

malignant tumor of cartilage producing cells leading to the formation of cartilage in bones and soft tissues

sxs
painful, progressively enlarging mass
swelling and local tenderness
possible pathological fractures

ETIIOLOGY:
arises from de novo cartilage cells

Question 21

Ewing sarcoma

Answer 21

highly malignant bone tumor characterized by small round blue cells commonly affecting the diaphysis of long bones and pelvis

GENETIC: EWS-FLI1 fusion gene
- adolescents and young adults

sxs
pain and swelling at tumor site
systemic symptoms: fever, weight loss and fatigue
possible palpable mass

Question 22

Osteoid Osteoma

Answer 22

benign bone tumor typically less than 2 cm, produces osteoid and woven bone surrounded by a zone of reactive bone formation

sxs
nocturnal pain releived by NSAIDs
localized tenderness and swelling
limp or scoliosis if affecting the spine

Question 23

Osteosarcoma

Answer 23

highly malignant bone tumor producitng osteoid, most commonly affecting the metaphysis of long bones
***distal femur, proximal tibia

Genetic: RB1, and TP53

metastasizes to bone and lungs

Question 24

Rhabdomyosarcoma

Answer 24

malignant tumor of skeletal muscle origin, commonly affecting head and neck, genitourinary tract and extremities

sxs
painless mass or welling
orbital, hematuria, vaginal bleeding
fever, weight loss