Investigating rolling as mechanism for humeral fractures in non-ambulant infants: a preliminary finite element study.

Abstract

AIM\nTo use personalised computed tomography (CT)-based finite element models to quantitatively investigate the likelihood of self-inflicted humeral fracture in non-ambulant infants secondary to rolling.\n\n\nMATERIALS AND METHODS\nThree whole-body post-mortem CT examinations of children at the age of rolling (two 4-month-old and one 6-month-old) were used. The mechanical moment needed by each infant to perform a rolling manoeuvre was calculated and applied to the finite element model in order to simulate spontaneous rolling from the prone to the supine position.\n\n\nRESULTS\nThe maximum predicted strains were found to be substantially lower (with a difference of >80%) than the elastic limit of the bone.\n\n\nCONCLUSION\nResults of this study challenge the plausibility of self-inflicted humeral fracture caused by rolling in non-ambulant infants and indicate that it is unlikely for a humeral fracture to result from this mechanism without the assistance of an external force.