Angle of insertion and confirmation of angles measured after in vitro implantation during laminar vertebral stabilization in vertebral columns obtained from canine cadavers

作者：Knell Sebastian C^*; Kircher Patrick; Dennler Matthias; Montavon Pierre M; Voss Katja; Hurter Karin

来源：American Journal of Veterinary Research, 2011, 72(12): 1674-1680.

Objective-To determine angles of insertion for laminar vertebral fixation of L1 and L2 by use of a locking plate in dogs and to confirm screw placement by use of computed tomography (CT).
Sample-Vertebral specimens harvested from 8 canine cadavers.
Procedures-The point of insertion and minimum and maximum insertion angles for laminar and facet screws for laminar vertebral stabilization were determined by use of CT. A precontoured locking plate was then placed by use of 1 locking screw in the lamina of each lumbar vertebra and 1 nonlocking screw in the facet joint. The position and angle of the screws were examined by use of CT and penetration into the vertebral canal was recorded.
Results-Mean +/- SD insertion angles for L1 and L2 were 18 +/- 4 degrees and 21 +/- 5 degrees toward the vertebral canal and 11 +/- 4.4 degrees and 10 +/- 30 degrees in a dorsal direction, respectively. Insertion angles for the facet joint were between 24 +/- 4 degrees ventrally and 12 +/- 2 degrees dorsally. Insertion of the screw did not penetrate the vertebral canal for 23 of 24 (96%) screws. For 23 of 24 inserted screws, the previously determined angle was maintained and purchase of bone and cortices was satisfactory.
Conclusions and Clinical Relevance-Placement of laminar and facet screws in canine vertebrae was possible and can be performed safely if angles of insertion determined pre-operatively via CT are maintained. (Am J Vet Res 201172:1674-1680)

• 出版日期2011-12