Aement of Biomechanic of Orbital Fracture: A tudy in Goat and Implication for Oculoplatic urgery in Human

Purpoe To determine the biophyical characteritic of energy aborption of the variou orbital tructure and the amount of force/energy required to produce an orbital fracture in goat, and to interpret reult in term of human clinical applicability. Deign Experimental animal tudy. Method The energy required to fracture the orbit on direct globe impact wa meaured. We ued a variety of other meaurement, including high-peed videography, intraocular preure, and intraorbital preure meaurement to decribe the biophyic of floor fracture. Twenty-one goat and 42 orbit were tudied in thi ingle intitutional ite tudy. Reult Our meaurement determined the fracture threhold for the caprine orbit averaged 26.5 N (E 3.1 N) with a total energy threhold for fracture of 2600 mJ (E 280 mJ). Eye deformation meaured 6 mm with deformation energy diipation meauring 100 to 180 mJ (E 10 mJ). Eye diplacement meaured 10 mm with diipation meauring 50 to 75 mJ (E 4.0 mJ). The deconvoluted bone fracture energy averaged 2350 mJ (E 260 mJ). Concluion Impact energy applied to the orbit through the eyeball i aborbed and diipated by three primary mechanim: (1) globe deformation, (2) globe diplacement, and (3) orbital fracture. Exce energy (above the energy required for deformation and diplacement) ≥2350 mJ will reult in an orbital fracture.