<unk> , also known as<unk>  club hand or<unk>  longitudinal deficiency, is a congenital difference occurring in a longitudinal direction resulting in<unk>  deviation of the wrist and shortening of the forearm. It can occur in different ways, from a minor anomaly to complete absence of the radius,<unk>  side of the carpal bones and thumb. Hypoplasia of the distal humerus may be present as well and can lead to stiffness of the elbow.<unk>  deviation of the wrist is caused by lack of support to the carpus,<unk>  deviation may be reinforced if forearm muscles are functioning poorly or have abnormal insertions. Although<unk>  longitudinal deficiency is often bilateral, the extent of involvement is most often asymmetric. The incidence is between 1:30,000 and 1:100,000 and it is more often a sporadic mutation rather than an inherited condition. In case of an inherited condition, several syndromes are known for an association with<unk> , such as the cardiovascular Holt-Oram syndrome, the gastrointestinal VATER syndrome and the hematologic Fanconi anemia and TAR syndrome. Other possible causes are an injury to the apical ectodermal ridge during upper limb development, intrauterine compression, or maternal drug use (thalidomide).
Radial dysplasia
Multiple epiphyseal dysplasia
Hip dysplasia
Carpal coalition
Metaphyseal dysplasia
Tarsal coalition
Tooth ankylosis
Leri pleonosteosis