Biophysical Bases for Delayed and Aberrant Motor Development in Young Children with Achondroplasia

Development in children with achondroplasia: a prospective clinical cohort study

“…2,4,6 The 90th centile ages of achievement for those items also assessed by Fowler et al 2 Commando crawling was the most frequently seen preorthograde movement strategy with 100% of the children demonstrating this (Table II). Half the sample (n=24) utilized reverse snow ploughing while forward snow ploughing and traditional crawling were the least frequently seen movement strategies.…”

“…Despite possible changes in management, results from this paper support previously published data by Fowler et al 2 that children with achondroplasia are delayed in the development of gross motor skills. While it is unclear whether children within the cohort studied by Fowler et al 2 were managed with restricted early sitting, it appears unlikely as data were collected from 93 children over a 14-year period. While most of the results for items in common were similar in the 90th centile age of achievement, rolling was reported much earlier in the current cohort (9.9mo vs 20mo).…”

“…7,12 Recommendations made within the Health Supervision Guidelines when implemented in the clinical setting may have influenced the timing and age of acquisition of developmental milestones since the previous prospective study. 2 For example, restricted early sitting and the resulting increased time spent in the supine and prone positions may influence the timing of later milestone development, e.g. walking and the types of preambulation strategies that a child utilizes.…”

“…Current results support previous findings that children with achondroplasia demonstrate a number of unique preambulation movement strategies including reverse and forward snow ploughing. 2,4 Commando crawling was the most popular preambulation motor strategy in all participants, which would allow children to accommodate the rhizomelic limb shortening and hypotonia more effectively, through increased proximity to the floor. Less than one-third (n=15) of the children demonstrated the more typical four-point crawling.…”

“…1 The primary biomechanical and anatomical differences seen in individuals with achondroplasia, which include marked limb shortening (more evident proximally than distally), macrocephaly, ligamentous laxity, and hypotonia, are known to contribute to developmental delays in motor skills, particularly during the first 2 years. [2][3][4][5][6][7] The delays seen in achievement of motor milestones indicate a clear need for achondroplasia-specific developmental trajectories against which to measure milestone attainment, allowing children to be compared directly with their peers. Three studies over the past 30 years have provided clinicians and families of children with achondroplasia with scattered, populationspecific developmental profiles across a range of gross motor, fine motor, feeding, and communication skills.…”