European Society of Biomechanics S.M. Perren Award 2018: Altered biomechanical stimulation of the developing hip joint in presence of hip dysplasia risk factors

Abstract

Fetal kicking and movements generate biomechanical stimulation in the fetal skeleton, which is important for prenatal musculoskeletal development, particularly joint shape. Developmental dysplasia of the hip (DDH) is the most common joint shape abnormality at birth, with many risk factors for the condition being associated with restricted fetal movement. In this study, we investigate the biomechanics of fetal movements in such situations, namely fetal breech position, oligohydramnios and primiparity (firstborn pregnancy). We also investigate twin pregnancies, which are not at greater risk of DDH incidence, despite the more restricted intra-uterine environment. We track fetal movements for each of these situations using cine-MRI technology, quantify the kick and muscle forces, and characterise the resulting stress and strain in the hip joint, testing the hypothesis that altered biomechanical stimuli may explain the link between certain intra-uterine conditions and risk of DDH. Kick force, stress and strain were found to be significantly lower in cases of breech position and oligohydramnios. Similarly, firstborn fetuses were found to generate significantly lower kick forces than non-firstborns. Interestingly, no significant difference was observed in twins compared to singletons. This research represents the first evidence of a link between the biomechanics of fetal movements and the risk of DDH, potentially informing the development of future preventative measures and enhanced diagnosis. Our results emphasise the importance of ultrasound screening for breech position and oligohydramnios, particularly later in pregnancy, and suggest that earlier intervention to correct breech position through external cephalic version could reduce the risk of hip dysplasia.

Femoral anteversion: significance and measurement

“…The internally rotated position of the hip joint during fetal life could also result in increased anteversion, and the opposite is true for external rotation (Watanabe, 1974). This was confirmed in animal studies with forced internal rotation (Wilkinson, 1962) and by the 10° higher FNA found in children born with breech presentation (Hinderaker et al, 1994); these children often have an internally rotated position in the womb resulting in reduced kicking forces and lower femoral stress and strain during fetal movements (Verbruggen et al, 2018). During childhood, a steady ~1.5° a year decrease in anteversion until completion of growth has been recorded ( Figure 5) (Fabry et al, 1973;Svenningsen et al, 1989;Tönnis and Heinecke, 1991).…”

Developmental Dysplasia of the Hip: A Review of Etiopathogenesis, Risk Factors, and Genetic Aspects

“…Factors such as oligohydramnios [30], high birth weight (HBW) or primiparity [18], present an increased risk for DDH.…”

Design of a Bioreactor to Assess the Effect of Passive Joint Loading in a Live Chick Embryo In Ovo

“…[1][2][3][4][5][6] In musculoskeletal tissues, the importance of mechanical cues in development is especially evident. 7 For example, breech position and other risk factors for developmental dysplasia of the hip are associated with reduced kick forces, 8 suggesting a link between mechanical loading and joint development. In addition, we have shown that altering embryo movement fre-quency in chick embryos in ovo affects lysyl oxidase (LOX) activity and mechanical properties of tendon.…”