Contact-constrained finite element analysis to evaluate obstetric forceps placement

Obstetric forceps are frequently used when physiologic childbirth fails to progress. It is commonly accepted in obstetrics that the use of the instrument is safe when placed and handled correctly. Conversely, obstetric forceps may cause significant damage to the fetal scalp, skull bones and brain if they are not applied correctly. In this paper, we assess obstetric forceps placement in-silico by creating virtual models of the fetal head and obstetric forceps. We establish mechanical contact between the fetal scalp and forceps blades. We then run implicit quasi-static Finite Element Analyses to assess the deformation of the fetal scalp when in contact with the forceps blades. Progressive steps are described to arrive at a final simulation that compares the symmetric placement of the forceps blades against their asymmetric placement. We show that the deformation of the fetal head is significantly more problematic when the forceps blades are asymmetrically placed relative to the fetal head.