title: Maximum forces applied to the orbital floor after fractures.
abstract: The objective of this study was to measure the force on and displacement of completely detached intraorbital tissue from the bony orbit, as a worst-case scenario after orbital trauma, to preserve the maximum load and predict the necessary strength of reconstruction materials. Six fresh-frozen human heads were used, and orbital floor defects in the right and left orbits were created by the direct impact of 3.0 J onto the globe and infraorbital rim. The orbital floor defect sizes and displacements were evaluated after performing a Le Fort I osteotomy. In addition, after the repositioning of the completely detached intraorbital tissue, the forces and displacements were measured. The mean orbital floor defect sizes were 208.3 (SD, 33.4) mm2 for globe impacts and 221.8 (SD, 53.1) mm2 for infraorbital impacts. The mean intraorbital tissue displacement after the impact and before repositioning was 5.6 (SD, 1.0) mm for globe impacts and 2.8 (SD, 0.7) mm for infraorbital impacts. After repositioning, the displacements were 0.8 (SD, 0.5) mm and 1.1 (SD, 0.7) mm, respectively. The measured forces were 0.10519 (SD, 0.00958) N without the incorporation and approximately 0.11128 (SD, 0.003599) N with the incorporation of reconstruction materials. The maximum forces on the completely detached orbital tissue were minimal (∼0.11 N) and suggest the use of collagen membranes as reconstruction materials for orbital floor defects, at least in medium-sized fractures.
authors.affiliation: Institute of Anatomy, Christian-Albrechts University Kiel, Otto-Hahn-Platz 8, 24118 Kiel, Germany. f.birkenfeld@anat.uni-kiel.de
authors.forename: Falk
authors.initials: F
authors.lastname: Birkenfeld
authors.forename: Martin
authors.initials: M
authors.lastname: Steiner
authors.forename: Matthias
authors.initials: M
authors.lastname: Kern
authors.forename: Jörg
authors.initials: J
authors.lastname: Witlfang
authors.forename: Björn
authors.initials: B
authors.lastname: Möller
authors.forename: Ralph
authors.initials: R
authors.lastname: Lucius
authors.forename: Stephan Thomas
authors.initials: ST
authors.lastname: Becker
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D006801:Humans; D008422:Materials Testing; D008875:Middle Aged; D009917:Orbital Fractures / Q000503:physiopathology* / Q000601:surgery*; D019340:Osteotomy, Le Fort; D019651:Plastic Surgery Procedures / Q000379:methods*; D013314:Stress, Mechanical