Résumé
Objective To introduce a new spinal surgery navigation system based on structured light scanning(structured light navigation system,SLNS),and to compare accuracy of pedicle screw placement using SLNS,CT based navigation system and free hand technique.Methods Thirty-two calf vertebral pedicles,40 and 32 were placed with pedicle screws using SLNS,CT navigation system,and free hand technique,respectively.The pedicle breakage ratio,transverse section angle (TSA),sagittal section angle (SSA),screw offset deviation of each screw were detected according to CT images.Results The pedicle breakage ratio of pedicle screws in SLNS group,CT navigation group and free hand group were 6%(2./32),5%(2/40),25%(8/32),respectively.The difference between each of the two navigation groups and free hand group were statistically significant regarding frequency of screw misplacement.The difference between the two navigation systems was not obvious.The average SSA error and TSA error in SLNS group were 2.58°±2.74° and 4.26°±5.20°.For CT navigation group,they were 2.95°±2.61° and 3.13°±-2.75°.There was no statistical difference between the two navigation methods for the SSA or TSA error.There was no statistical difference in offset deviation among SLNS group,CT navigation group and free hand group.Conclusion The SLNS is a new and practical navigation system,which has similar accuracy with CT navigation system.