A novel guide device improves the accuracy of pedicle screw placement

Pedicle screw placement in thoracic and lumbar spine is technically demanding and involves radiation exposure. Commercially available systems for pedicle screw insertion are expensive and cannot be widely used for those less-developed areas. The purpose of our study was to develop a simple guide device assisting pedicle screw placement and improving the accuracy in the operation. A simple guide device was developed with the aim of improving accuracy of pedicle screw technique based on anatomical structures of the spine. We retrospectively collected clinical data of 111 consecutive patients who received treatment of pedicle screw internal fixation between January 2013 and September 2014. In total, 518 screws were inserted by the same surgeon, among which 280 screws were implanted in 60 patients (33 males and 27 females) with conventional freehand technique and 238 screws were implanted in 51 patients (27 males and 24 females) using the guide device. According to postoperative CT evaluation, screws were classified into different grades and accuracy rates were compared between the two groups. A total of 518 screws were placed (238 in the guide group, 280 in the conventional group). No intra-operative or postoperative complications such as infection, vessel and nerve injuries occurred. After postoperative CT evaluation, 215 from guide group and 236 from the conventional group were classified in Grade 1. Only screws in Grade 1 were considered as accurate insertion. Thus, the accuracy rates were 84.3% for the conventional group and 90.3% for the guide group respectively. Through statistical test, there was significant difference in the accuracy rate between two groups. The simple guide device significantly improves the accuracy of pedicle screw placement. Combined with the advantage of cheapness, it can be widely used in spinal internal fixations, especially suitable for those inexperienced spine surgeons in less-developed areas.