Abstract
Purpose and Background
Both overall spine shape and the size and shape of individual vertebrae undergo rapid growth and development during early childhood. Motor development milestones such as age of walking influence spine development, with delayed ambulation linked with spinal conditions including spondylolysis. However, it is unclear whether associations between motor development and spine morphology persist into older age. Therefore, these associations were examined using data from the MRC National Survey of Health and Development, a large nationally-representative British cohort, followed up since birth in 1946.
Methods and Results
Statistical shape modelling was used to characterise spinal shape (L5-T10) and identify modes of variation in shape (SM) from dual energy x-ray absorptiometry images of the spine taken at age 60–64 years (N=1327 individuals; 51.8% female). Associations between walking age in months (reported by mothers at 2 years) and SMs were examined with adjustment for sex, birthweight, socioeconomic position, height, lean mass and fat mass.
Later onset of independent walking was weakly associated with greater lordosis (SM1; P=0.05) and more uniform antero-posterior vertebral size along the spine (SM6, P=0.07). Later walking age was also associated with smaller relative anterior-posterior vertebral dimensions (SM3) among women whereas the opposite was found for men (P <0.01 for sex interaction).
Conclusions
Spinal morphology in early old age was associated with the age that individuals began walking independently in childhood, potentially due to altered mechanical loading. This suggests that motor development may have a persisting effect on clinically-relevant features of spine morphology throughout life.
Conflict of interest: None
Funded by the UK Medical Research Council (Grant MR/L010399/1) which supported FRS, SGM and AVP
