Lower Extremity Polydactyly Does Not Disturb Finding One's Feet

Little is known about functional outcomes in children with treated lower extremity polydactyly (LEP). No classification system has been shown to be prognostically useful for functional outcomes. This study investigates whether children with treated LEP learn to walk at an age comparable to the population and whether the SAM (severity of syndactyly, axis deviation and metatarsal involvement) classification system is prognostically useful. In a retrospective cohort of 18 patients, we tested for associations between patient characteristics and SAM scores, age at learning to walk, and ability to fit off-the-shelf shoes. The proportion of children with treated LEP able to walk at 18 months of age was compared with the general population. We found no association between the age at which the 17 participants learned to walk and the severity of syndactyly (p =. 214), axis deviation (p =. 723) and metatarsal involvement (p =. 781), nor between the proportion of patients able to wear off-the-shelf shoes compared to those requiring extra wide off-the-shelf shoes and the severity of syndactyly (p = 1.000), axis deviation (p = 1.000) and metatarsal involvement (p = 1.000). We found a trend between older age at surgery and the need for extra wide off-the-shelf shoes (OR = 1.008, p =. 080). We found no significant difference in the proportion of children able to walk at 18 months between our patients (proportion = 1.00) and the general population (proportion = 0.95) (p = 1.000). We found no significant association between different SAM scores and functional outcomes, and none in the proportion of children able to walk at 18 months between treated LEP patients and the general population.