Milestone Attainment in Young Children With Arthrogryposis Multiplex Congenita: Developmental Profile and Associated Factors.

Evidence on developmental milestones in children with arthrogryposis multiplex congenita (AMC) under the age of five is scarce. This multisite cross-sectional study described developmental status and examined factors associated with milestone attainment in 143 children aged 0-66 months from a pediatric AMC Registry. Development was assessed using the Ages and Stages Questionnaire, Third Edition (ASQ-3), across Communication, Gross Motor, Fine Motor, Problem-Solving, and Personal-Social domains. Independent variables included demographic, perinatal, clinical, and parental factors. Gross Motor function was the most limited domain, with more than 90% scoring close to/below the ASQ-3 domain-specific cutoff (≥ 2 SD below normative mean). Personal-Social scores were unexpectedly low, and Fine Motor limitations were also frequent, with 53.1% scoring close to/below the cutoff. Communication and Problem-Solving were relative strengths. Longer neonatal intensive-care unit stays were linked to poorer Communication and Fine Motor scores, and higher birth weight was associated with better Problem-Solving performance. Specific joint contractures, particularly those affecting the neck, shoulder, elbow, and knee, were associated with lower performance across domains, while higher parental education was related to better Personal-Social outcomes. Developmental attainment in AMC is shaped by interactions among musculoskeletal, perinatal, and family factors, underscoring the importance of early, coordinated orthopedic, developmental and family-centered interventions.