Gross motor delays in infants and young boys with Duchenne muscular dystrophy

Abstract

Background Duchenne muscular dystrophy (DMD), an X-linked progressive neurodegenerative disorder, is being added to required universal screening programs for newborns in the United States. It is estimated that this will result in around 880 patients presenting at clinics in infancy. Very little is known about the early gross motor abilities in infants and young boys with DMD. Objective Describe the early gross motor skill acquisition in boys in our clinic with DMD. Methods Between the years 2016 and 2024, 90 boys with DMD under the age of 6 years (2 months – 5 years 10 months at their first visit) were evaluated as part of their standard of care during regularly scheduled clinic visits using the using the Bayley Scales of Infant & Toddler Development, Third Edition (Bayley-III). Forty-seven boys were seen in clinic longitudinally with two to six follow up visits for a total of 129 assessments. Results Ninety four percent of the boys with DMD seen in our clinic demonstrated delays in gross motor skills across the age span when compared with normative controls. None of the boys reached a ceiling on the Bayley-III despite being older than the intended age range of the test. Conclusions Our clinic data showed an almost universal gross motor delay in infants and toddlers that did not diminish over time.