Fetal movements are known to play a key role in prenatal skeletal development. We know this from a number of conditions in which reduced or restricted fetal movements are linked to abnormal  affecting newborn babies in which the bones or joints are not properly formed. The most common example is developmental dysplasia of the hip (DDH), where the hip joint is unstable or even dislocated. Another example is arthrogryposis, where multiple joints are abnormally shaped and oriented. We characterised- for the first time- the stresses and strains induced by fetal movements in the bones and joints, and how these stimuli are altered in conditions that predispose a baby to hip dysplasia. We created computational models of babies kicking in utero and calculated the stresses and strains induced in the bones and joints by these kicks.

Dr Stefaan Verbruggen was the postdoctoral researcher leading the research, and the project was funded by Arthritis Research UK (now Versus Arthritis).

Methods

Fetal movements are automatically tracked from cine MRI scans (obtained from our collaborators at King’s College London) as shown below.

Those movements are modelled using finite element and musculoskeletal models to calculate the force generated by the kick, and the muscle forces acting. Next, the muscle forces are applied to fetal skeletal geometries, obtained from collaborators in Great Ormond Street Hospital. The methodological pipeline is shown below.

Publications

Verbruggen SW, Kainz B, Shelmerdine SC, Arthurs OJ, Hajnal JV, Rutherford MA, Phillips AT, Nowlan NC. “Altered biomechanical stimulation of the developing hip joint in presence of hip dysplasia risk factors”. Journal of Biomechanics, in press. Winner of European Society of Biomechanics Perren Award for best scientific paper. (link) (pdf)

Verbruggen SW, Loo JHW, Hayat TTA, Hajnal JV, Rutherford MA, Phillips ATM, Nowlan NC, “Modelling the biomechanics of fetal movements”, 2016. Biomechanics and Modelling in Mechanobiology: 15(4), pp. 995-1004. (link) (pdf)