Arthritis imaging

Question 1

Which study should you order first?

Answer 1

an xray/ plain radiograph ordered first

gives overview and xray corrlated to other non xray studies

Question 2

Why order a CT scan?

Answer 2

if cortical bone is to be evaluated, for early or subtle change
good anatomy detail

Question 3

Why order an MRI?

Answer 3

if soft tissue and marrow edema inducing pathology to be studied
highly sensitive

Question 4

How do you choose MRI or CT?

Answer 4

second study based on pathology

Question 5

Bone scan?

Answer 5

more multiple sites/screens

metastasis

Question 6

Arthritis?

Answer 6

disease affecting joint space, bones and soft tissues on both sides of articulation

Question 7

Classify, 4 types of arthritis?

Answer 7

Degenerative
Inflammatory
Septic/infection/osteomyelitis
Metabolic

Question 8

Degenerative?

Answer 8

osteophytes, subchondral sclerosis, loss of joint space-usually uneven, cysts (geodes)

Question 9

Inflammatory?

Answer 9

eroisions, juta-articualr osteoporosis, uniform loss of joint space, usually soft tissue swelling

Question 10

Septic/infection/osteomyelitis?

Answer 10

rapid onset, usually monarticular, effusion, bone destruction/demineralization

Question 11

Metabolic?

Answer 11

lumpy/bumpy soft tissue swelling, characteristic marginated bony erosion with overhanging edges

Question 12

Osteoarthritis?

Answer 12

Disruption/ injury/ degeration of articular cartilage eventually exposing subchondral bone

diarthrodial weight bearing joints, 1 cmc and mtp joints and dip joints of hands, increased incidence with age

any arthritis can develop into this

aggregated by use, relieved by rest, morning stiffness

Question 13

Osteoarthritis-DJD?

Answer 13

cyst formation, long standing

Question 14

eburnation?

Answer 14

occurs at areas of cartilage loss

Question 15

DJD of hand?

Answer 15

CMC joint

nodes

Question 16

Rheumatoid Arthritis?

Answer 16

Autoimmune/ connective tissue disorder
bilaterally symmetric, soft tissue swelling
2nd and 3rd MCP, 4th and 5th MTP of feet

late- eroisions, marked joints, space narrowing, joint destruction, subchondral cyst, subluxation, fusion, acetabuli protusio (acetabulum into hip)

Question 17

Eburnation with RA?

Answer 17

no

Question 18

Other signs of RA?

Answer 18

atlantoaxial subluxation
eroision
osteopenia, joint space narrowing

Question 19

Septic arthritis?

Answer 19

infection most commonly spread hematogenously from synovium to joint

rapid course, early cortical destruction, pain/swelling, signs of infection (WBS) and monoarticular
high index of suspicion and joint aspiration

Question 20

Septic arthritis Xray findings?

Answer 20

joint effusion, periarticular osteoporosis, destruction of articular cartilage and cortex on both side of jt rapid onset

Question 21

Sign of septic arthritis?

Answer 21

severly irregular cortex- white line destruction

Question 22

Tuberculous arthritis?

Answer 22

insidious course, may take months to have same appearance as pyogenic takes days/weeks

synovitis with pannus leads to chrondronecrosis
phemister triad-gradual, slow joint space narrowing, marginal eroisions, juxtaartricular osteoporosis
condused with atypical monoarticular RA

Question 23

Sequestration?

Answer 23

space with bone in it

Question 24

Acute osteomyelitis?

Answer 24

new born formation, abscess, effusion, soft tissue swell, rule out tumor

Question 25

Diabetic osteomyelitis?

Answer 25

less bony density, osteopenia, irregular vascular calcification--diabetes significant soft tissue swell

Question 26

Three phase bone scan?

Answer 26

hot- tumors, infections, cellulitis with bone | cellulitis- wont see increased activity

Question 27

Crystal induced arthropathy?

Answer 27

CPPD and Gout crystal deposition in cartilage and soft tissues, inflammation CPPF: Chondrocalcinosis with arthritis resembling OA, subchondral cysts

Question 28

Joints involved Crystal induced arthropathy?

Answer 28

knee, wrist, and hip involvement common | more common in males

Question 29

Chondrocalcinosis?

Answer 29

seen with gout and crystal deposit well outlined disc calcification in joint

Question 30

Classic gout?

Answer 30

1st MTP classic, erosion with overhanging edge, joint space maintained

Question 31

Advantages of plain xray?

Answer 31

quick, not expensive, relatively low radiation

Question 32

Disadvantage of plain xrays?

Answer 32

not 3D, can miss pathology, may still require other imaging studies

Question 33

CT scanning?

Answer 33

excellant anatomic detail will detect almost all pathology related to cortical bone injury great for showing displacement or joint involvement

Question 34

Advantages of MRI?

Answer 34

no radiation we can slice through the body using any imaging plane MRI is very good for looking at the soft tissues MRI is very sensitive in detecting water

Question 35

Bone scan?

Answer 35

Tc99m labeled MDP injected into a vein tracer accumulates in osteblasts increased osteoblasts in fracture, tumor and infection