<unk>  is a very rare medical condition in which the<unk>  bone is not developed. This results in a typical position of the arm in which the wrist is plantarflexed and radially deviated.
The aetiology of radial club hand or radial dysplasia can be divided into:
VACTERL or VATER syndrome
Holt-Oram syndrome
Edwards syndrome
haematopoietic syndromes:
Fanconi anemia
Thrombocytopaenia with<unk>  (TAR syndrome)
craniofacial syndromes:
Nager's syndrome
Goldenhar's syndrome
Mobius syndrome
cleft lip and palate
Treacher-Collins syndrome
skeletal syndromes and isolated skeletal associations:
Klippel-Feil syndrome
Sprengel deformity
syndactyly
scoliosis
teratogens:
radiations
valproic acid
thalidomide
Fanconi anemia
Thrombocytopaenia with<unk>  (TAR syndrome)
Nager's syndrome
Goldenhar's syndrome
Mobius syndrome
cleft lip and palate
Treacher-Collins syndrome
Klippel-Feil syndrome
Sprengel deformity
syndactyly
scoliosis
radiations
valproic acid
thalidomide
Absent radius
Dislocated patella x ray
Accessory navicular bone
Bipartite patella
Carpometacarpal bossing
Accessory spleen
Varus deformity
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