Objective:To analyze the learning curve of TiRobot-assisted lumbar pedicle screw fixation (LPSF) by cumulative sum (CUSUM) test method.Methods:The clinical data of 50 patients who underwent TiRobot-assisted LPSF from January 2020 to December 2022 in Beijing Friendship Hospital, Capital Medical University were retrospectively analyzed. CUSUM analysis and learning curve fitting were performed with robot usage time as the main indicator with the time for each step refined (robot registration time, path planning time and guide wire placement time), to select the best learning curve fitting model with the R2 value closest to 1. Using the turning point of the learning curve as the boundary, the learning curve was divided into two stages as learning stage and maturity stage, and then the observation indexes were compared between the two stages. Results:All 50 patients successfully completed the surgery without perioperative complications, with a total of 244 pedicle screws implanted. The total robot usage time and robot registration time showed a gradually decreasing trend with the increase of case number, and the learning curves were successfully fitted and reached their peaks at the seventeenth and thirteenth cases respectively. The entire learning process was divided into learning stage (17 cases) and maturity stage (33 cases) based on the turning point of the learning curve of total robot usage time. The path planning time and guide wire placement time did not show significant changes with the increase in the case number. The total robot usage time, robot registration time and the intraoperative blood loss in the learning stage were significantly higher than those in the maturity stage: (35.35 ± 1.58) min vs. (30.61 ± 0.43) min, (20.83 ± 1.56) min vs. (14.94 ± 0.29) min and 400 (150, 500) ml vs. 200 (110, 300) ml, the guide wire placement time of per screw was significantly lower than that in the maturity stage: 2.00 (1.83, 2.34) min/screw vs. 2.33 (2.13, 2.69) min/screw, and there were statistical differences ( P<0.05 or <0.01). There were no statistical difference in the path planning time, path planning time of per screw, guide wire placement time and the accuracy of screw placement between two stages ( P>0.05). Conclusions:TiRobot-assisted LPSF is a new technology with safety and effectiveness, and it has a relatively short learning curve. To achieve technological maturity, at least 17 surgeries are required with accumulated experience, and the robot registration is the main step of the learning process. After reaching maturity stage, the robot usage time is significantly shortened and intraoperative trauma is significantly reduced while the relatively high screw placement accuracy is ensured.

Objective:To analyze the reoperation rate and causes during the early adoption phase of unilateral biportal endoscopy (UBE).Methods:The clinical data of 180 patients who underwent UBE performed by a single surgeon at Beijing Friendship Hospital, Capital Medical University from October 2021 to June 2023 were retrospectively analyzed. Clinical and imaging data of patients who underwent reoperation were collected to analyze the causes of reoperation, and the clinical efficacy of the reoperations was also followed up. Measurement data were expressed as mean ± standard deviation ( ± s), and t-test was used before and after treatment. Results:A total of 180 patients who underwent UBE were included in this study, of which 6 patients underwent reoperation, and the reoperation rate was 3.33%. Among them, 3 cases occurred in the first 90 surgeries and the other 3 occurred in the subsequent 90 surgeries. The causes of reoperation were as follows: recurrent lumbar disc herniation at the same segment postoperatively in 2 cases, insufficient decompression in 2 cases, disc herniation following isolated decompression in 1 case, and immediate postoperative perianal numbness in 1 case. The time between the initial surgery and reoperation ranged from 0 to 187 days, with an average of 63.3 days. The average follow-up time after reoperation was 18.3 months. The visual analogue scale (VAS) and Oswestry disability index (ODI) scores of the patients at the last follow-up were significantly improved compared with those before operation (VAS score of low back pain: 5.2 ± 1.7 before operation, 1.2 ± 0.8 at the last follow-up, P<0.001; VAS score of leg pain: 7.2 ± 1.5 before operation, 1.2 ± 1.2 at the last follow-up, P<0.001; ODI score: 67.3 ± 5.7 before operation, 20.2 ± 8.2 at the last follow-up, P<0.001). The postoperative modified MacNab scores were generally satisfactory (4 cases were rated as excellent, accounting for 66.7%; 2 cases were rated as good, accounting for 33.3%). Except for one patient who experienced dural injury during open revision surgery, there were no serious complications such as nerve damage. Conclusions:In the early stages of UBE surgery, recurrent lumbar disc herniation and inadequate decompression are the primary reasons for reoperation, typically occurring within the first three months postoperatively. Reoperation does not significantly increase the risk of nerve injury. Enhanced early postoperative follow-up is recommended. For symptomatic patients, a second surgery with thorough decompression can yield satisfactory treatment outcomes.

Objective:To evaluate the safety and efficacy of the TiRobot assisted screw placement in patients with lumbar degenerative diseases.Methods:The clinical data of 165 patients with lumbar degenerative diseases from January 2020 to December 2022 in Beijing Friendship Hospital, Capital Medical University were retrospectively analyze, and all patients were treated with posterior lumbar decompression and instrumentation. Among them, 46 patients were used the TiRobot assisted screw placement during surgery (robotic-assisted group), and 119 patients underwent freehand screw placement by C-arm X-ray machine fluoroscopy (freehand group). The operation time, intraoperative blood loss, complication and skelalgia visual analogue scale (VAS), Oswestry disability index (ODI) before and after operation were recorded. The accuracy of screw placement and rate of proximal facet joint violation were compared between two groups.Results:There were no statistical difference in operation time, intraoperative blood loss and incidence of complication between two groups ( P>0.05). In the two groups, the 3 d VAS and ODI after operation were significantly lower than those before operation, robot-assisted group: (3.33 ± 1.40) scores vs. (6.54 ± 2.00) scores and (16.96 ± 8.03) scores vs. (43.09 ± 5.48) scores; freehand group: (3.56 ± 1.29) scores vs. (6.55 ± 1.65) scores and (18.89 ± 6.74) scores vs. (44.91 ± 4.96) scores, and there were statistical differences ( P<0.01); there were no statistical difference in VAS and ODI before operation and 3 d after operation between two groups ( P>0.05). A total of 234 screws were implanted in robot-assisted group, and 590 screws were implanted in freehand group. The accuracy of screw placement in robot-assisted group was significantly higher than that in freehand group: 80.77% (189/234) vs. 74.58% (440/590), the rate of proximal facet joint violation was significantly lower than that in freehand group: 2.56% (6/234) vs. 7.29% (43/590), and there were statistical differences ( χ2 = 3.56 and 6.68, P<0.05). Conclusions:The TiRobot assisted screw placement for lumbar degenerative diseases is safe and effective. Compared to freehand technique, the TiRobot assisted method demonstrates higher screw placement accuracy and a lower rate of proximal facet joint violation.

Objective:To analyze the learning curve of TiRobot-assisted lumbar pedicle screw fixation (LPSF) by cumulative sum (CUSUM) test method.Methods:The clinical data of 50 patients who underwent TiRobot-assisted LPSF from January 2020 to December 2022 in Beijing Friendship Hospital, Capital Medical University were retrospectively analyzed. CUSUM analysis and learning curve fitting were performed with robot usage time as the main indicator with the time for each step refined (robot registration time, path planning time and guide wire placement time), to select the best learning curve fitting model with the R2 value closest to 1. Using the turning point of the learning curve as the boundary, the learning curve was divided into two stages as learning stage and maturity stage, and then the observation indexes were compared between the two stages. Results:All 50 patients successfully completed the surgery without perioperative complications, with a total of 244 pedicle screws implanted. The total robot usage time and robot registration time showed a gradually decreasing trend with the increase of case number, and the learning curves were successfully fitted and reached their peaks at the seventeenth and thirteenth cases respectively. The entire learning process was divided into learning stage (17 cases) and maturity stage (33 cases) based on the turning point of the learning curve of total robot usage time. The path planning time and guide wire placement time did not show significant changes with the increase in the case number. The total robot usage time, robot registration time and the intraoperative blood loss in the learning stage were significantly higher than those in the maturity stage: (35.35 ± 1.58) min vs. (30.61 ± 0.43) min, (20.83 ± 1.56) min vs. (14.94 ± 0.29) min and 400 (150, 500) ml vs. 200 (110, 300) ml, the guide wire placement time of per screw was significantly lower than that in the maturity stage: 2.00 (1.83, 2.34) min/screw vs. 2.33 (2.13, 2.69) min/screw, and there were statistical differences ( P<0.05 or <0.01). There were no statistical difference in the path planning time, path planning time of per screw, guide wire placement time and the accuracy of screw placement between two stages ( P>0.05). Conclusions:TiRobot-assisted LPSF is a new technology with safety and effectiveness, and it has a relatively short learning curve. To achieve technological maturity, at least 17 surgeries are required with accumulated experience, and the robot registration is the main step of the learning process. After reaching maturity stage, the robot usage time is significantly shortened and intraoperative trauma is significantly reduced while the relatively high screw placement accuracy is ensured.

Objective:To evaluate the safety and efficacy of the TiRobot assisted screw placement in patients with lumbar degenerative diseases.Methods:The clinical data of 165 patients with lumbar degenerative diseases from January 2020 to December 2022 in Beijing Friendship Hospital, Capital Medical University were retrospectively analyze, and all patients were treated with posterior lumbar decompression and instrumentation. Among them, 46 patients were used the TiRobot assisted screw placement during surgery (robotic-assisted group), and 119 patients underwent freehand screw placement by C-arm X-ray machine fluoroscopy (freehand group). The operation time, intraoperative blood loss, complication and skelalgia visual analogue scale (VAS), Oswestry disability index (ODI) before and after operation were recorded. The accuracy of screw placement and rate of proximal facet joint violation were compared between two groups.Results:There were no statistical difference in operation time, intraoperative blood loss and incidence of complication between two groups ( P>0.05). In the two groups, the 3 d VAS and ODI after operation were significantly lower than those before operation, robot-assisted group: (3.33 ± 1.40) scores vs. (6.54 ± 2.00) scores and (16.96 ± 8.03) scores vs. (43.09 ± 5.48) scores; freehand group: (3.56 ± 1.29) scores vs. (6.55 ± 1.65) scores and (18.89 ± 6.74) scores vs. (44.91 ± 4.96) scores, and there were statistical differences ( P<0.01); there were no statistical difference in VAS and ODI before operation and 3 d after operation between two groups ( P>0.05). A total of 234 screws were implanted in robot-assisted group, and 590 screws were implanted in freehand group. The accuracy of screw placement in robot-assisted group was significantly higher than that in freehand group: 80.77% (189/234) vs. 74.58% (440/590), the rate of proximal facet joint violation was significantly lower than that in freehand group: 2.56% (6/234) vs. 7.29% (43/590), and there were statistical differences ( χ2 = 3.56 and 6.68, P<0.05). Conclusions:The TiRobot assisted screw placement for lumbar degenerative diseases is safe and effective. Compared to freehand technique, the TiRobot assisted method demonstrates higher screw placement accuracy and a lower rate of proximal facet joint violation.

Adjacent segment disease(ASD) refers to the degeneration of adjacent segments after lumbar fusion surgery, including intervertebral disc herniation, stress vertebral fractures, slippage, segmental scoliosis, spinal canal stenosis, and facet joint degeneration, which can lead to corresponding clinical symptoms such as lumbosacral pain, root lower limb pain, or intermittent claudication. The treatment of different pathological types of ASD varies. The patients with mild symptoms require conservative treatment and patients with severe symptoms require surgical treatment. In the past, open fusion surgery with posterior approach or intervertebral foramen approach was commonly used for surgical treatment, which had definite therapeutic effects. However, there were drawbacks such as large surgical trauma, excessive intraoperative blood loss, and slow postoperative recovery. With the booming development of minimally invasive spinal surgery technology in recent years, spinal surgeons actively use minimally invasive surgery for the treatment of ASD. It has advantages such as less bleeding, short hospital stay, fast recovery, and fewer complications (such as deep vein thrombosis and pulmonary embolism), but its indications are limited. Therefore, this article provides a reference for the choice of ASD treatment by reviewing the treatment modalities of ASD with different pathological types.