COMPUTER-ASSISTED PEDICLE SCREW INSTALLAT ION - FIRST 3 CASES

Pedicle screw fixation is sometimes a difficult surgical procedure rel ying on anatomical landmarks that may be modified by vertebral asymmet ries. A significant incidence of cortex penetration and neuro-vascular complications have been documented. Our study evaluates the usefulnes s of a computer-aided pedicle installation system and analyses the res ults for our first 3 clinical cases, The system was used for 3 adolesc ent patients with idiopathic scoliosis undergoing surgical correction and instrumentation. In all cases, selected vertebrae were reconstruct ed in 3D pre-operatively. At surgery, the surgeon compared the compute r-suggested pedicle location to his own opinion; After pedicular hole drilling was done in the usual fashion, hole positions were confirmed per-operatively with the computer software. Post-operatively, software hole positions were measured and compared to the actual screw axis us ing CT-Scans. Three dimensional models produced for all selected verte brae allowed visualization of asymmetrical deformations of the scoliot ic vertebrae. All pedicles were correctly detected by the software. Pe dicular hole measurements agreed with the actual screws positions on p ost-op CT-Scans. The computerized surgical assistant can be of value i n a clinical situation, These initial results warrant a large scale tr ial in order to establish accuracy and reliability.