Comparative Biomechanical Study of Cervical Spine Stabilisation by Cage Alone, Cage with Plate, or Plate-Cage: A Porcine Model

PURPOSE: To compare stability and subsidence associated with 3 types of cervical spine stabilisation. METHODS: The C3 to C4 vertebrae of 28 Polish pigs were used. Pigs with intact vertebrae (group 1) underwent standard anterior cervical discectomy (group 2), followed by stabilisation using a cage alone (group 3), a cage with plate (group 4), or a plate-cage (group 5). Cervical spine stability and subsidence were compared in all 5 groups. RESULTS: Stability was significantly increased after stabilisation by a cage with plate or a plate-cage, but not by a cage alone. The difference between stabilisation by a cage with plate and a plate-cage was not significant. Subsidence was maximal after the cage-alone stabilisation (3.1 mm), being 1.6 mm after the cage-with-plate and plate-cage stabilisations. CONCLUSION: Additional plating as a supplement to anterior interbody cervical cage stabilisation significantly improves segmental stability and subsidence.