Congenital hand

Question 0

Apical ectodermal ridge

Answer 0

Proximal to distal growth, secretes FGF

Question 1

Swanson classification

Answer 1

Congenital hand deformities 1968

1 failure of formation
2 failure of differentiation
3 duplication
4 overgrowth
5 undergrowth
6 congenital constriction band
7 generalised skeletal deformities

Question 2

Zone of Polarising Activity

Answer 2

Area of mesenchyme at the posterior limb secretes sonic hedgehog.
AP differentiation.

Question 3

Dorsal-ventral axis

Answer 3

wingless-type mouse mammary tumor virus integration site family mem-ber 7a (Wnt-7a)
Molecular factor found in the ectoderm.

Question 4

Blauth classification

Answer 4

Thumb hypoplasia
1 minor generalised hypoplasia
2 hypoplastic/absent thenar muscles, web space narrowed, MCPJ UCL instability
3 extrinsic muscle abnormalities, skeletal deficiency (MC, carpal bones). Type A stable CMCJ, Type B unstable CMCJ.
4 pouce flotant
5 complete aplasia

Question 5

Bayne’s classification

Answer 5

Ulnar longitudinal deficiency 1982

1 hypoplasia
2 partial aplasia
3 total aplasia
4 radiohumeral synostosis

Question 6

Apert’s hand

Answer 6

Type 1 - spade
Type 2 - mitten
Type 3 - rosebud

Question 7

Kirner’s deformity

Answer 7

Curvature of DP of little finger in a radial and palmar direction
Presents in females age 7-14

Question 8

Blauth classification

Answer 8

Thumb hypoplasia 1967

1 - small thumb, all components present
2 - small thumb, lax UCL
3 - absent thenar muscles, abnormal extrinsics
4 - pouce flottant
5 - absent thumb

Manske modification 1977
3A - normal CMCJ and MC length
3B - unstable CMCJ

Question 9

Patterson’s classification

Answer 9

Constriction ring 1961

1 simple soft tissue - groove
2 distal deformity +/- lymphoedema
3 constriction with distal fusion (acrosyndactyly)
- I tips joined
- II tips joined, web creep
- III tips joined, complete syndactyly with proximal sinus
4 resultant amputation