A Dutch retrospective study shows that the lag in the overall development of boys with DMD is noticeable from the age of 2 months

A Dutch study involves a cohort of 76 participants with DMD aged under 26, recruited by invitation via two patient associations, and compared with other data from the medical monitoring of more than 12,000 young people not affected by the disease.
The authors have compiled data from early childhood developmental assessments obtained through clinical monitoring with the Dutch Development Instrument (DDI), an assessment tool used in the Netherlands. It covers 72 activities in 3 areas of development – fine motor activity / adaptive and social behavior, communication, gross motor activity.

The study is based on two types of information:

  • data on the early development of participants, from evaluation made during early clinical follow-up, from 1 month of age to 4 years of age.
  • responses to a questionnaire offered to the parents of participants at the time of inclusion in the study, and comprising items on motor, behavioral and social skills in real life (the responses of 43 parents out of 76 were used).

Data in clinical and real life; a noticeable difference from the age of 2 months
The results show the existence of a delay in the acquisition of fine motor skills, gross motor skills, adaptive responses and communication between the group affected by DMD and the control group, from the age of 2 to 3 month.
So soon after birth, the developmental gap is not yet noticeable, it gradually becomes so.

Regarding fine motor activity, little explored so far, the results show that:

  • at 2 months, 22% of children with DMD cannot follow their gaze by moving their head (10.1% in the control group);
  • at 9 months, 6% fail to catch both feet (1% in the control group);
  • at 12 months, 18% of children with DMD fail to pick up an object between the thumb and forefinger (7.9% in the control group);
  • at 3 years, 33% of children with DMD fail to reproduce a vertical line by drawing it (9.3% in the control group).

These data, obtained very early in childhood, should encourage earlier detection and management of Duchenne muscular dystrophy.


Early developmental milestones in Duchenne muscular dystrophy. van Dommelen P, van Dijk O, de Wilde JA, Verkerk PH. Dev Med Child Neurol. 2020;10.1111/dmcn.14623.