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Paediatrics
advanced
X-Type

Thumb Hypoplasia - Blauth Classification and Pollicization

Paediatric Upper Limb

A 6-month-old infant is referred with bilateral small thumbs noted at birth. The right thumb is smaller than the left with an unstable MCP joint. Examination reveals a hypoplastic thenar eminence, absent opposition, and an unstable ulnar collateral ligament. The CMC joint is present and stable. Radiographs show a hypoplastic first metacarpal with all phalanges present. The hand surgeon discusses the Blauth classification and treatment options. Regarding thumb hypoplasia and the Blauth classification:

Mark each as TRUE or FALSE

A

BLAUTH CLASSIFICATION of thumb hypoplasia: Type I = minor hypoplasia (small but functional); Type II...

B

The critical distinction is between IIIA and IIIB: Types I-IIIA have a STABLE CMC joint and are amen...

C

Blauth Type IIIB thumbs should undergo reconstruction rather than pollicization because they retain ...

D

POLLICIZATION involves transposition of the index finger to thumb position with: shortening and rota...

E

Thumb hypoplasia is commonly associated with RADIAL LONGITUDINAL DEFICIENCY (radial club hand); VACT...

Answer the questions to see explanations

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