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Hand & Upper Limb
intermediate
X-Type

Polydactyly

Congenital Hand Anomalies

A 6-month-old infant is referred with a duplicated thumb. The parents noticed the extra digit at birth. Examination reveals two well-formed thumbs on the left hand with a common metacarpophalangeal joint. The radial thumb is slightly smaller and deviates ulnarly. Radiographs show bifurcation at the level of the proximal phalanx with both components having separate distal phalanges. Regarding polydactyly:

Mark each as TRUE or FALSE

A

Polydactyly is classified as preaxial (radial/thumb), central (index-ring), or postaxial (ulnar/smal...

B

The Wassel classification is used for thumb duplication (Types I-VII); Type IV (duplicated proximal ...

C

Polydactyly is always isolated with no syndromic associations; the Wassel classification applies to ...

D

Surgical principles for thumb duplication include: preserving the larger, more functional digit; rec...

E

Associated syndromes must be considered: preaxial polydactyly with Holt-Oram syndrome (cardiac defec...

Answer the questions to see explanations

Click T (True) or F (False) for each option