OBJECTIVE: To evaluate the correct placement of transpedicular screws in the thoracic, lumbar and sacral spine using the free hand technique. METHODS: Clinical and imaging (CT scan) evaluation of 25 patients (13 female and 12 male) undergoing spinal instrumentation for a total of 124 transpedicular screws applied using the free hand technique. The screws were inserted from T11 to S1, most of which were placed at levels L4, L5 and S1. RESULTS: 94% of transpedicular screws were placed correctly in the pedicle. It was found that 6% (seven screws) were misplaced and among those, only two violated the inferomedial wall, one less than 2 mm and the other between 2 and 4 mm. None of the patients had complications associated with incorrect positioning of the screws. CONCLUSION: The free hand technique is safe to be used in the instrumentation of the thoracic, lumbar and sacral spine.
Lumbar vertebrae; Bone screws; Spinal fusion
