Should we recommend occipital plate fixation using bicortical screws or inverted occipital hooks to optimize occipito-cervical junction fusion? A biomechanical study combining an experimental and analytical approach

Autor: Jean-Pierre Richer, A. Delmotte, Louis Petureau, Pascal Doumalin, Jean-Christophe Dupré, Fabrice Brémand, Philippe Maxy, Arnaud Germaneau, Tanguy Vendeuvre, S. d’Houtaud, Philippe Rigoard, Cyril Breque
Přispěvatelé: Institut Pprime (PPRIME), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Centre hospitalier universitaire de Poitiers (CHU Poitiers), Medtronic SNT, Medtronic, Laboratoire d’Anatomie, Biomécanique et Simulation (ABS Lab), Université de Poitiers - Faculté de Médecine et de Pharmacie, Université de Poitiers-Université de Poitiers-Université de Poitiers - Faculté de Sciences fondamentales et appliquées, Université de Poitiers
Rok vydání: 2020
Předmět:
Zdroj: Clinical Biomechanics
Clinical Biomechanics, Elsevier, 2020, 80, pp.105173-. ⟨10.1016/j.clinbiomech.2020.105173⟩
ISSN: 1879-1271
0268-0033
DOI: 10.1016/j.clinbiomech.2020.105173⟩
Popis: Background Occipito-cervical fusion can be necessary in case of cranio-cervical junction instability. Proximal stabilisation is usually ensured by bi-cortical occipital screws implanted through one median or two lateral occipital plate(s). Bone thickness variability as well as the proximity of vasculo-nervous elements can induce substantial morbidity. The choice of site and implant type remains difficult for surgeons and is often empirically based. Given this challenge, implants with smaller pitch to increase bone interfacing are being developed, as is a surgical technique consisting in inverted occipital hook clamps, a potential alternative to plate/screws association. We present here a biomechanical comparison of the different occipito-cervical fusion devices. Methods We have developed a 3D mark tracking technique to measure experimental mechanical data on implants and occipital bone. Biomechanical tests were performed to study the mechanical stiffness of the occipito-cervical instrumentation on human skulls. Four occipital implant systems were analysed: lateral plates+large pitch screws, lateral plates+hooks, lateral plates+small pitch screws and median plate+small pitch screws. Mechanical responses were analysed using 3D displacement field measurements from optical methods and compared with an analytical model. Findings Paradoxical mechanical responses were observed among the four types of fixations. Lateral plates+small pitch screws appear to show the best accordance of displacement field between bone/implant/system interface providing higher stiffness and an average maximum moment around 50 N.m before fracture. Interpretation Stability of occipito-cervical fixation depends not only on the site of screws implantation and occipital bone thickness but is also directly influenced by the type of occipital implant.
Databáze: OpenAIRE
Externí odkaz: