Bone

Question 1

Answer 1

Cleidocranial Dysplasia

AD

Also get wormian bones

Question 2

Frond like fatty tissue affecting the joint or bursa

Answer 2

Lipoma Arborescens

5th-7th decades

Bright on T1 and T2 and saturates on fat sat sequences

Question 3

Answer 3

Enchondromas

Syndromes:

Ollier’s (multiple enchondromas), Mafucci’s (multiple enchondromas + hemangiomas/so you see phleboliths)

Question 4

Answer 4

Fibrous Dysplasia

Syndromes:

McCune Albright (polyostotic fibrous dysplasia, precocious puberty and cafe au lait spots)

Mazabraud (fibrous dysplasia and soft tissue myxomas)

Question 5

2.5 year old boy who won’t bear weight

Answer 5

Osteomyelitis

typical appearance and location for osteomyelitis.

Extension into the epiphysis is typical; may be seen with tumors but more common with osteomyelitis.

The diffuse sclerosis surrounding the lytic lesions represents typical host reaction to the infection.

Question 6

34M with forefoot pain

Answer 6

Psoriatic Arthritis

erosions in the metatarsophalangeal (MTP) and interphalangeal (IP) joints is nonspecific.

However, the florid periostitis strongly suggests either psoriatic arthritis or chronic reactive arthritis.

Question 7

Answer 7

Haglund deformity

”pumps bump”

postero-superior calcaneus from high heels usually

Question 8

Answer 8

Synovial chondromatosis

synovial proliferation leading to multiple cartilaginous loose joint bodies–some ossify

1*– 4th-5th decades, M >F, unknown cause, Knee>Hip>elbow>shoulder

2*– to degenerative changes, fewer and larger fragments, older population, other degenerative findings\

T1

Question 9

Answer 9

CRMO

Multiple sites of osteomyelitis

dx of exclusion

Question 10

Answer 10

Brody abscess

rim lining of an abscess cavity with higher signal intensity than that of the main abscess on T1–>penumbra sign, subacute OM

Question 11

Define:

sequestrum

involucrum

cloaca

sinus tract

Answer 11

• sequestrum: infectious source itself
• involucrum: bone’s response
• cloaca: once it breaks the cortex
• sinus tract: leads to the skin

Question 12

What type of arthritis?

Characteristics?

Answer 12

Erosive OA

old women

See Erosions–> Gull wing deformity

predominantly the IPs, (1st CMC cannot get erosive OA)

Question 13

Stress fractures in healthy young adults vs insufficiency fractures of the hip

locations

Answer 13

Young otherwise healthy adult: basicervical femoral neck (medially)

Old osteopenic/porotic people: subcapital

Question 14

Bennett lesion?

Answer 14

posterior excrescence on the glenoid

seen in pitchers

Question 15

how do we know if this fracture is intraarticular in extension?

Answer 15

Boehler angle is reduced (normally 20-40, here is 10)

CT can confirm (sanders classification)

Question 16

boutonniere deformity

Answer 16

flexed PIP with extended DIP

disruption of middle slip of extensor tendon

can also fracture

Question 17

what is this structure

Answer 17

lateral femoral condylar recess OR condylopatellar sulcus

so its the left femoral condyle

if this is >2mm it is suggestive of ACL injury

Question 18

Answer 18

pencil in cup deformity

Psoriatic Arthritis

Almost always accompanies skin disease, especially nail changes

Mostly involves DIP joints of hands > feet

• There is often resorption of terminal phalanges (acro-osteolysis)
• There is usually no osteoporosis

Question 19

widened physis in an active ped (like a gymnast)

Answer 19

Salter harris I

trauma related osteolysis

Wrists in gymnasts, ankles in runners, proximal humerus in pitchers

Question 20

maisonneuve fracture?

Answer 20

medial malleolar fracture (or deltoid ligament rupture) and syndesmotic disruption extending up the leg with high fibular fracture

deltoid ligament rupture:

presumed with valgus stress, see opening of the medial joint clear space, **Deltoid ligament has to be completely ruptured to allow opening of the joint space

soft tissue swelling location distal to malleolus

(pic is of unstable weber B fracture with deltoid rupture)

Question 21

chronic navicular fracture with remodeling and altered morphology?

Answer 21

Muller-Weiss disease

Question 22

Ulnar variance–what happens with postive and negative?

Answer 22

Positive ulnar variance can cause ulnar impaction syndrome: proximal lunate develops sclerosis, subchondral cysts, and osteophytes

negative ulnar variance: get ulnar impingement syndrome: see edema and degenerative change in ulna/radius.

Can also see lunate osteonecrosis (keinboch malacia..sclerosis + edema in lunate)

Question 23

cortical endosteal and periosteal reaction in a bilateral symmetric distribution

Answer 23

progressive diaphyseal dysplasia

(Engelman Camerati)

Question 24

what do you think of?

Answer 24

Teres muscle edema: think axillary nerve pathology and

quadrilateral space syndrome

Question 25

what does this patient have

In the setting of systemic sclerosis, what do they need?

Answer 25

this is acroosteolysis

in a patient with progressive systemic sclerosis

they need pulmonary screening (get ILD)

Question 26

Buford complex

Answer 26

’cord like’ middle glenohumeral lligament

and partial absence of the anterosuperior labrum
(most of the Labral variants are at the AS aspect, make your mind up about it before you get here)

Question 27

Patterns of psoriatic arthritis

Answer 27

Patterns of Psoriatic Arthritic Changes

Arthritis involving multiple joints with DIP joint involvement

Arthritis resembling Rheumatoid Arthritis

Sacroiliitis (asx–PAIR) and spondylitis (pic)

Arthritis mutilans

Question 28

Erosion of the distal clavicle, think of which pathologies?

Answer 28

Hyperparathyroidism

RA

Question 29

Answer 29

Osteitis condensans ilii

benign, incidental finding (a stress reaction)

Question 30

long lesion in a long bone, think of?

Answer 30

Fibrous dysplasia

*if patient has known renal disease, or you see lots of vascular calcs etc, think of brown tumors