A Biomechanical Evaluation of Auricular Cartilage Autografts in Orbital Floor Defect Repair.

Published

Journal Article

OBJECTIVE: Auricular cartilage is used as a surgical implant in the management of orbital floor fractures. However, no specific parameters exist regarding the use/limitations of this potential graft. In order to determine the mechanical efficacy of adult auricular cartilage grafts, a mechanical model was developed and studied for structural threshold size limits. METHODS: Thirty-seven cadaveric auricular cartilage specimens were tested in a laboratory. A plexiglass baseplate was created with four different sized holes, defined as 1.0×, 1.2×, 1.4×, and 1.6× the mean minor axis of the specimens. Each specimen was used to bridge one hole under increasing loads until mechanical failure. Structural stiffness at three different loading stages, structural failure strength, and percent failure of the entire system for each defect size was calculated. RESULTS: Specimens tested on 1.0×, 1.2×, 1.4× and 1.6× defects demonstrated 0%, 0%, 20%, and 60% system failure rates, respectively. Structural stiffness curves showed a similar trend, with ANOVA demonstrating a significant difference in mechanical properties between defect sizes (p = 0.03). The curve representing 1.6 × defect size demonstrated significantly reduced structural stiffness relative to 1.0×, 1.2×, and 1.4× curves. There was no statistical difference between 1.2× and 1.4× testing sets (p = 0.09). CONCLUSION: A clinically significant biomechanical and functional threshold exists between 1.2×and 1.4× defect sizes. Given a mean minor axis of 2.06 cm, orbital blow-out defects <2.4 cm (1.2 × 2.06 cm) are suitable for auricular cartilage grafts; fractures >2.4 cm may require a more rigid material. Cartilage grafts that allow failure, however, may better protect the globe in subsequent injury.

Full Text

Duke Authors

Cited Authors

  • O, TM; Richard, MJ; Cullinane, DM; Binetter, DJ; Fay, A; Der Sarkissian, R

Published Date

  • June 2015

Published In

Volume / Issue

  • 34 / 3

Start / End Page

  • 121 - 126

PubMed ID

  • 25905861

Pubmed Central ID

  • 25905861

Electronic International Standard Serial Number (EISSN)

  • 1744-5108

Digital Object Identifier (DOI)

  • 10.3109/01676830.2015.1014504

Language

  • eng

Conference Location

  • England