RÉSUMÉ
BACKGROUND: 3D printed bone model was widely used in clinical teaching and simulated surgery training, but it did not pay enough attention to the construction of soft tissue, and the simulation was poor, which cannot reflect the soft tissue exposure process. OBJECTIVE: To explore the feasibility of constructing a simulated lumbar spine surgery model based on 3D printing technology for the training of lumbar pedicle screw placement in junior orthopedic surgeons. METHODS: The solid model of the lumbar spine was printed at the same proportion based on 3D printing technology, and the model of simulated lumbar spine surgery was constructed with plasticine and cloth. Thirty orthopedic residents performed lumbar pedicle screw placement alone on the simulated model, and performed once a day for 10 consecutive days. They recorded the operation time, and evaluated the accuracy of screw placement by postoperative CT scan. By comparing the operation time and screw placement accuracy of the operators in the early stage (the first 5 times) and the later stage (the last 5 times), all above parameters were statistically analyzed. This study was approved by the Ethics Committee of Zigong Fourth People's Hospital. RESULTS AND CONCLUSION: (1) In the early stage (the first 5 times), the average operation time was (100. 00+12. 67) minutes. In the later stage (the last 5 times), the average operation time was (83. 50+10. 14) minutes, and the difference was statistically significant (f=20. 67, P=0. 00). (2) The success rate of former screw placement (including grade I and II screw placement) was 88. 53%, and the failure rate (grade III screw placement) was 11. 47%. The success rate and failure rate of latter screw placement were 97. 47% and 2. 53%, respectively, with statistically significant difference (x2-20. 68, P=0. 00). (3) The simulated model of lumbar spine surgery based on 3D printing technology has high simulation and feasibility, and can be used for the training of lumbar pedicle screw placement in junior orthopedic surgeons.