Orbital blowout trauma occurring at the workplace - clinical, biomechanical and legal aspects

Introduction and objective. Craniofacial injury at the workplace may lead to orbital blowout fractures. The aim of the study is the development of own numerical model of the eye orbit, assessment of the damage zones, and comparing them with clinical examinations. In addition, the current legal status of patients after injuries is presented. Materials and method. In laboratory tests performed on bones collected from the upper and medial orbital wall (examination on fresh corpses), the Young’s modulus was determined for these bones. Based on the CT image, a numerical model of the eye orbit was created. The damage zones within the eye socket were assessed after a blow (dynamic model) to the inferior and lateral walls, and only to the inferior wall. Comparative clinical material were 9 patients with orbital blowout fracture treated at the Clinic of Otolaryngology Results. Experiment 1: the damage zone covered an area of 0.54cm2, and was located medially and laterally from the infraorbital nerve canal. Experiment 2: the damage zone was smaller – 0.38 cm2, and located medially to the infraorbital nerve canal. The results obtained in the experiment were compared with the CT image of the eye sockets of patients after injuries. On this basis, presumptions were made concerning the mechanism of the trauma. Conclusions. The finite element method is a good tool for assessing the pathomechanism of trauma, as well as for an attempt to determine the circumstances of the event. Based on analysis of the numerical and clinical images, the necessity for using protective measures which absorb the impact to the inferior wall and temporal areas should be emphasised, as well as the fact that using merely goggles is insufficient protection of the eye orbit.