Human Phenotype Ontology term HP_0006433 (Radial ray deficiency) is radial dysplasia, also known as radial longitudinal deficiency, includes radial clubhand and is a disfiguring, and potentially disabling, congenital limb anomaly. The entire upper limb may be involved, although the defect is most evident in the forearm and hand. Affected children suffer a variable degree of hypoplasia or absence of the preaxial skeleton and soft tissues, in particular the thumb, radius, and dorsoradial soft tissues. The hand is usually radially deviated and subluxated off the distal aspect of the ulna, the ulna may be shortened and have a bow-shaped deformity, and there is no true wrist (radiocarpal) joint in Bayne2 type-III and IV radial dysplasia. Also known as: Abnormal radial ray morphology, Deformity of radial ray, Dysplastic radii, Radial club hand, Radial dysplasia, Radial longitudinal deficiency, Radial ray anomaly, Radial ray deformity.