Mechanisms of orbital blowout fracture: a critical review of the literature

Abstract

The aim of the present study is to critically review relevant literature regarding the mechanism of blowout fractures of the orbit and provide an answer to the question: Can one theory adequately explain the mechanism of orbital blowout fractures in the light of present day knowledge? A computerised literature search using MEDLINE was conducted for published articles on orbital blowout fractures. Mesh phrases used in the search were: orbital blowout fractures AND mechanisms; orbital blowout fractures AND theory; orbital wall injury AND mechanisms. Only relevant articles were selected for the review. The physical mechanism of orbital blowout fracture has been a subject of debate for years by maxillofacial surgeons, ophthalmologists, plastic surgeons, otolaryngologists and orbitologists. However, only 3 mechanisms of injury have been proposed namely: "hydraulic" theory, "globe-to-wall" theory and "bone conduction" theory. Most of the theories of orbital blowout fractures have been confirmed through brilliant experiments and hypothetical explanation/analysis of clinical and radiologic findings, and each one appears to fit according to the different type of trauma received. Based on contemporary evidence, one theory may not adequately explain all types of fractures completely or be responsible exclusively in a given case for the pattern of fracture observed. Blowout fractures of the orbit could therefore be due to a combination of 2 or more mechanisms.