The Use of Polyaxial Pedicle Screw for the Fusion of Lumbar Vertebra in Sheeps

Abstract

In this study, 10 sheeps with the average age of 1.5 years old, weighing approximately 50-70 kg were used. Hemilaminectomy was performed in the interspace between L(4) and L(5) on the left side. The pedicle screws were attached to each other by means of a rod and the fixation process was accomplished by screwing the nods on the top of the screws. Cortical bone graft obtained during the decortications of proc. transversus and proc. articularis and of laminas in the interspace between L(3) and L(6) was combined with grafts taken from ilium and placed between proc. transversuses. No screw loosed in none of the cases in 12 weeks period. Radiographic assessments were made on the 4, 8 and 12th weeks. In the assessments on 12th week, it was observed that ankylosis was completely formed.