Embryology
Picture ID
Anomalies 1
Anomalies 2
Surgery
1

100 POINTS EACH

Limb bud formation begins by ___ weeks

Hand plate visible by ____ weeks

All limb structures present by ___ weeks


Limb bud formation begins by 4 weeks

Hand plate visible by 5 weeks

All limb structures present by 8 weeks

1

300 POINTS

What is this deformity? What syndrome is it most commonly associated with?

Clinodactylyl (angulation deformity due to bracketed epiphysis at middle phalanx)

Seen in almost 80% of people with Down Syndrome

1

800 POINTS

Describe the Blauth Classification. Hint: comment on size of thumb, thenar musculature, webspace, and joints. 

Classification of thumb dysplasia

Type I: Minor hypoplasia, normal thenar muscles, webspace, and carpus

Type II: Contracted webspace, underdeveloped/absent thenar muscles, unstable MP UCL

Type IIIA: Marked hypoplasia, metacarpal hypoplasia, stable CMC joint

Type IIIB: Same as IIIA with UNstable CMC joint

Type IV: "Pouce flottant" floating thumb, with vascular abnormalities, absent metacarpal, neural rings, etc

Type V: Absent thumb

1

100 POINTS

Failure of what process in utero causes syndactyly?

Apoptosis

1

200 POINTS

What is the treatment of choice for Blauth Type II-IIIA hypoplasia? 

Opponensplasty + webspace deepening/tendon recon etc. 

2

800 POINTS

What growth factor regulates proximodistal growth?

FGF (Fibroblast growth factor) 

2

300 POINTS


Amniotic Band Syndrome

2

300 POINTS

Describe the "radial club hand" deformity.

Shortening of the forearm and radial deviation of the wrist due to hypoplasia or aplasia of radius


2

400 POINTS

What is pollex abductus?

Abnormal connection between EPL and FPL

2
100 POINTS


Where does a pollicization most often borrow from?

Index finger

3

400 POINTS

What growth factor dictates anteroposterior growth? 

SHH (sonic hedgehog) 

3

150 POINTS
What medication did this pregnant woman take that caused this associated birth anomaly? (BONUS 50: What was the indication for this drug in pregnancy?)


Thalidomide

Morning sickness

3

200 POINTS

What is the most common site of congenital amputation?

Proximal third of forearm (below elbow) 

3

200 POINTS

Define:

simple vs complex syndactyly

complete vs incomplete syndactyly


Simple: skin involvement only

Complex: bone involvement

Complete: Fusion from webspace to fingertip

Incomplete: Fusion of webspace, does not extend all the way to fingertip

3

300 POINTS

What is the most common forearm procedure performed for ulnar deficiency?

Corrective osteotomy of the radius, to address bowing

4

DAILY DOUBLE

What growth factor regulates dorsoventral differentiation?

Wnt gradients, LMX-1, EN-1

4

500 POINTS

What is the anomaly and what syndromes is this XR MOST LIKELY to be associated with?

Radial aplasia, associated with TAR (thrombocytopenia absent radius) 

This is less likely to be VACTERL, Holt-Oram, or Fanconi Anemia because thumbs are intact/normal appearing

4

200 POINTS

Define camptylodactyly

Tightness of skin, fascia, or FDS causing flexion contracture at IP joint, most often in SF

4

200 POINTS

What percentage of trigger thumbs seen in infancy will resolve spontaneously by 1 year?

30%

4

300 POINTS

What is the timing for syndactyly release?

3-9 months if there are digits of unequal length involved

Otherwise release at 1-2 years

5

600 POINTS

What is the apical ectodermal ridge and what is the zone of polarizing activity? Be specific. 

AER - area of growth in proximodistal axis

ZPA- area of growth in anteroposterior/radioulnar axis 

5

700 POINTS

Name the defect and what syndrome it is most often associated with?


Triphalangeal thumbs, associated with Diamond Blackfan Anemia

Also associated with Holt-Oram, Aase, and Townes-Brock syndromes

5

200 POINTS

In mirror hand, the hand is usually missing what digit?

Complete duplication of ulnar portion of hand, usually missing thumb
5
100 POINTS


What is the most common anomaly of the human hand?

Polydactyly

5

200 POINTS

What is an indication to do surgical amniotic band release early in infants?

Usually done at 1-2 years

Can be done earlier is there is impending autoamputation or necrosis 

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