Abstract
Metacarpal synostosis is an uncommon hand anomaly that may occur in isolation (ring-small metacarpal) or in connection with a congenital syndrome (Apert, Ellis–van Creveld). It has been hypothesized to be sporadically inherited via x-linked recessive or autosomal dominant traits and is possibly linked to a genetic abnormality in the FGF16 gene. This hand difference likely forms during the first 4–8 weeks of gestation during rapid development of the upper limb.
Children are most often evaluated due to parental concerns regarding a deviated finger, most commonly the small finger that is abducted from the hand. Radiographic examination can confirm the diagnosis of metacarpal synostosis. Treatment is guided by symptoms and digital function. Operative treatments involving osteotomy and bone graft interposition. Though multiple techniques address deformity and length discrepancy, affected digits may remain hypoplastic and stiff and may benefit from amputation.
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Acosta, A.M., Light, T.R. (2023). Metacarpal Synostosis. In: Pajardi, G. (eds) Pediatric Hand Surgery. Springer, Cham. https://doi.org/10.1007/978-3-031-30984-7_18
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DOI: https://doi.org/10.1007/978-3-031-30984-7_18
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