MSK-OPe, OP, OCD/OCL, RSD, osteochondroses

Question 1

osteopenia-definition, mcc

Answer 1

• bone lucency.

- OP=mcc

Question 2

looser zones-what, where, appearance, mcc’s, type of fracture

Answer 2

also known as cortical infractions, Milkman lines or pseudofractures, are wide, transverse lucencies with sclerotic borders traversing partway through a bone, usually perpendicular to the involved cortex, and are associated most frequently with osteomalacia and rickets.

• type of insufficiency fracture
• wide Lucent bands traversing at right angles to cortex
• MC=femoral neck, pubic rami
• img: sclerosis surrounding lucency
• MCC=OM, Rickets; OI (less common)

Question 3

osteoporosis-what, causes, appearance, complications

Answer 3

• low bone density (peaks at 30 yo)
• age (faster in menopause), mx (steroids, heparin, dilantin), endocrine (Cushings, HyperPTH), anorexia, OI
• compl: fractures (spine –> hip –> wrist)

Question 4

order of osteoporotic involved fractures

Answer 4

spine –> hip –> wrist

Question 5

DEXA-T and Z score

Answer 5

Measure of bone mineral density.

• Z score density relative to age-matched control
• T score= density relative to young adult. Defines Ope, OP

Question 6

Significance of Dexa T score: T > -1, -1–>-2.5, <2.5

Answer 6

> 1= N

• 1–>-2.5 = Ope
• <2.5=OP

Question 7

DEXA FPs & FNs

Answer 7

• FP: absent normal structures (ex: s/p laminectomy)

- FN: excessive osteophytes, dermal calcification, metal; too much femoral shaft , compression fx

Question 8

FRAX

Answer 8

Fracture Risk Assessment Tool-predict fractures by RFs +/- femoral neck bone density

• 10 yr fracture risk
• who would benefit from pharmacologic intervention:
  
  • hip fracture risk >3%
  • major fracture risk >20%
• M & F
• recommended for T score -1 –> -2.5

Question 9

Reflex Sympathetic Dystrophy (RSD)/Complex Regional Pain Syndrome/Sudeck Atrophy-what, mc locs, app (Rgx, bone scan)

Answer 9

• minor trauma, infection –> SNS overflow –> persistent pain, tenderness & swelling
• MC=hand, shoulder
• app:
  
  • rgx: severe OPe. UL RA w/ preserved joint spaces
  • 3phase hot bone scan - juxta/?intra-articular uptake 2/2 increased vascularity of synovial membrane
  • delayed always hot

Question 10

Transient osteoporosis

Answer 10

1) transient OP of hip

2) regional migratory OP

Question 11

transient OP of hip-who, where, appearance, mx

Answer 11

• F, 3rd TM, left hip
• MC in men, BL
• app:
  
  • Rgx: OPe
  • MR: edema
  • Bone scan: focal+
  • joint space normal
• mx: self-limited ~ mo’s

Question 12

regional migratory OP-what, who, app, mx

Answer 12

• idiopathic, M>F
• pain in joint –> resolving –> another joint
• self limited

Question 13

transient osteoporosis vs AVN vs Fx

Answer 13

• TO=OPe–> Lucent
• TO vs AVN: both STIR+, T1-, joint effusion
  
  • AVN serpiginous line
• Fx- line less serpiginous

Question 14

osteoporotic compression fracture- MR app

Answer 14

T1 dark band like fracture line. T2 variable

Question 15

neoplastic compression fracture-when, app, next step

Answer 15

• Entire VB replaced with tumor
• diffuse abN sign (not band-like) most prom pst
• next step: look at rest of spine

Question 16

what does dark marrow represent? When is it bad?

Answer 16

• marrow infiltration
• red marrow
• bad = darker than adjacent (N) disc

Question 17

osteochondritis dissecans/lesions (OCD/OCL)-what, why, where, complications, mx

Answer 17

• trauma, AVN –> aseptic sep osteochondral fragment –> fragmentation of articular surface, 2˚OA
• femoral condyle (MC), patella, talus, capitellum
• OA if unstable

Question 18

Staging OCD/OCL

Answer 18

Stage 1-stable, covered by intact cartilage, con’t w/ host bone
Stage 2-stable on probing, partial discon’t w/ host bone
Stage 3-unstable on probing, complete discon’t
Stage 4-dislocated fragment

Question 19

unstable OCD/OCL

Answer 19

high T2 signal undercutting fragment from bone

-edema=FP

Question 20

capitellum lesions: OCD vs panner’s vs pseudo lesion

Answer 20

• OCD: 12-16 yo throwers. Ant convex margin. +/- loose bodies
• Panners: 5-10 yo throwers (Peter Pan). Entire capitellum. (-) LBs
• PL- Pst sloping looks like defect on coronal img

Question 21

capitellum pseudo-lesion

Answer 21

pst capitellum looks like defect on coronal img due to abrupt slope

Question 22

osteochondroses

Answer 22

group of osteonecrotic conditions involving epipyhysis/apophysis (usually childhood) with collapse, sclerosis, and fragmentation

Question 23

Kohler’s osteochondrosis

Answer 23

• tarsal navicular
• Boys 4-6 yo
• mx-conservative

Question 24

Freiberg infraction

Answer 24

• 2nd metatarsal head
• adolescent girls
• 2˚ OA

Question 25

Sever’s osteochondrosis

Answer 25

• calcaneal apophysis

- “normal growing pain?”

Question 26

Panner’s osteochondrosis

Answer 26

• capitellum

- 5-10 yo throwers

Question 27

Perthes (LCP)

Answer 27

• femoral head

- 4-8 yo caucasian

Question 28

Kienbock osteochondrosis

Answer 28

• carpal lunate; ass w/ negative unar variance

- 20-40 yo

Question 29

Scheuermann osteochondrosis

Answer 29

• thoracic spine

- kyphosis > 40˚ + 3 adj VB wedging

Question 30

what is normal AP kyphotic curvature of spine

Answer 30

-20-40˚

Question 31

Sinding-Larsen-Johansson (SLJ)

Answer 31

inferior patella

-10-15 yo jumper

Question 32

osgood-schlatter disease

Answer 32

• tibial tubercle
• 10-15 yo’s, jumper, kicker
• fragmentation + ST swelling