Factors Associated With Functional Mobility in 256 Children With Arthrogryposis Multiplex Congenita: A Multicentric Cross-Sectional Study.

OBJECTIVE

To describe functional mobility among children, adolescents, and young adults with arthrogryposis multiplex congenita (AMC) and identify factors associated with mobility outcomes.

DESIGN

Multisite cross-sectional study.

SETTING

Eight orthopedic hospitals for children.

PARTICIPANTS

A total of 256 individuals (N=256) aged 5-21 years with a confirmed clinical diagnosis of AMC were recruited between October 2019 and December 2022. AMC subtypes included amyoplasia (n=122), distal arthrogryposis (n=62), and Central Nervous System (CNS)/syndromic AMC (n=39).

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: Functional mobility was assessed using the mobility domain of the Functional Independence Measure for Children (WeeFIM) and the Gillette Functional Assessment Questionnaire (FAQ). Multivariable models were used to examine associations with perinatal and current clinical and environmental factors.

RESULTS

Children with CNS/syndromic and amyoplasia subtypes demonstrated significantly lower WeeFIM scores (coefficients [Exp(B)]=0.74 and 0.85, respectively; both P<.05) and reduced odds of higher FAQ levels (adjusted odds ratio [AOR]=0.16 and 0.18, respectively; both P<.001) compared with those with distal arthrogryposis. Greater joint involvement, particularly at the knees, was a strong negative factor. Each additional perinatal joint contracture was associated with a 3.1% reduction in WeeFIM scores (Exp(B)=0.97, P<.001) and an 8.2% decrease in the odds of higher FAQ levels (AOR=0.92, P<.05). Current knee involvement was associated with a 27.7% reduction in WeeFIM scores (Exp(B)=0.72, P<.001) and nearly 90% lower odds of higher FAQ levels (AOR=0.10, P<.001). Parental unemployment (AOR=0.44, P<.05) and higher musculoskeletal surgical burden (AOR=0.24, P<.001) were significantly associated with poorer mobility.

CONCLUSIONS

This is the largest cohort to date examining functional mobility in AMC. Clinical and socioeconomic factors identified may guide tailored rehabilitation strategies to promote positive outcomes in children with AMC.