Radial Longitudinal Deficiency: A Contemporary Clinical Review From Deformity to Function

Radial longitudinal deficiency (RLD), historically known as radial club hand, is a congenital malformation of the upper limb in which the structures along the preaxial (radial) axis -the thumb, radius, radial carpal bones, and radial-sided soft tissues -are hypoplastic or absent.It occurs across a broad spectrum, from isolated thumb hypoplasia to complete radial aplasia, which may be accompanied by radial deviation of the wrist, forearm shortening, and impaired hand function.Its clinical importance extends well beyond the visible limb difference: a substantial proportion of affected children have systemic anomalies, and RLD can be the presenting sign of conditions with major health implications, including Fanconi anemia, Holt-Oram syndrome, thrombocytopenia-absent radius syndrome, VACTERL association, and Baller-Gerold syndrome.Because these disorders carry independent hematologic, cardiac, renal, and other risks, early recognition and systemic evaluation are integral to the initial assessment rather than secondary to it.Classification systems that describe both the radial deficiency and the associated thumb hypoplasia help stratify severity and guide management, while evaluation is directed at both the limb and possible systemic involvement.Management is individualized and multidisciplinary, spanning hand surgery, genetics, occupational therapy, and psychosocial support, and combines nonoperative measures with surgical reconstruction in more severe cases.The evidence base remains limited, consisting largely of small, heterogeneous, retrospective series with variable outcome measures and short follow-up; however, important questions about optimal technique and timing remain unresolved.Optimal care therefore depends on individualized, multidisciplinary treatment planning that prioritizes long-term function, growth preservation, and the psychosocial well-being of patients and their families.