Objective To explore the feasibility and accuracy of ultrasound volume navigation (UVN) combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation through a prospective randomized controlled study. Methods Patients with thoracic and lumbar vertebral fractures scheduled for percutaneous pedicle screw fixation between January 2022 and January 2023 were enrolled. Among them, 60 patients met the selection criteria and were included in the study. There were 28 males and 32 females, with an average age of 49.5 years (range, 29-60 years). The cause of injury included 20 cases of traffic accidents, 21 cases of falls, 17 cases of slips, and 2 cases of heavy object impact. The interval from injury to hospital admission ranged from 1 to 5 days (mean, 1.57 days). The fracture located at T12 in 15 cases, L1 in 20 cases, L2 in 19 cases, and L3 in 6 cases. The study used each patient as their own control, randomly guiding pedicle screw implantation using UVN combined with X-ray fluoroscopy on one side of the vertebral body and the adjacent segment (trial group), while the other side was implanted under X-ray fluoroscopy (control group). A total of 4 screws and 2 rods were implanted in each patient. The implantation time and fluoroscopy frequency during implantation of each screw, angle deviation and distance deviation between actual and preoperative planned trajectory by imaging examination, and the occurrence of zygapophysial joint invasion were recorded. Results In terms of screw implantation time, fluoroscopy frequency, angle deviation, distance deviation, and incidence of zygapophysial joint invasion, the trial group showed superior results compared to the control group, and the differences were significant (P<0.05). Conclusion UVN combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation can yreduce screw implantation time, adjust dynamically, reduce operational difficulty, and reduce radiation damage.
ObjectiveTo compare the effective of short-segment pedicle instrumentation with bone grafting and pedicle screw implanting in injured vertebra and cross segment pedicle instrumentation with bone grafting in injured vertebra for treating thoracolumbar fractures. MethodsA prospective randomized controlled study was performed in 40 patients with thoracolumbar fracture who were in accordance with the inclusive criteria between June 2010 and June 2012. Of 40 patients, 20 received treatment with short-segment pedicle screw instrumentation with bone grafting and pedicle screw implanting in injured vertebra in group A, and 20 received treatment with cross segment pedicle instrumentation with bone grafting in injured vertebra in group B. There was no significant difference in gender, age, affected segment, disease duration, Frankel grade, Cobb angle, compression rate of anterior verterbral height, visual analogue scale (VAS) score, and Japanese Orthopaedic Association (JOA) score between 2 groups before operation (P>0.05). The operation time, blood loss, Cobb angle, compression rate of anterior vertebral height, loss of disc space height, Frankel grade, VAS and JOA scores were compared between 2 groups. ResultsThere was no significant difference in the operation time and blood loss between 2 groups (P>0.05). Primary healing of incision was obtained in all patients, and no early complication of infection or lower limb vein thrombus occurred. Forty patients were followed up 12-16 months (mean, 14.8 months). No breaking or displacement of internal fixation was observed. The improvement of Frankel grading score was 0.52±0.72 in group A and 0.47±0.63 in group B, showing no significant difference (t=0.188, P=0.853) at 12 months after operation. The Cobb angle, compression rate of anterior verterbral height, and VAS score at 1 week and 12 months, and JOA score at 12 months were significantly improved when compared with preoperative ones in 2 groups (P<0.05). No significant difference was found in Cobb angle, disc space height, VAS score, and JOA score between 2 groups at each time point (P>0.05), but the compression rate of anterior verterbral height in group A was significantly lower than that in group B (P<0.05). The loss of disc space height next to the internal fixation or the injured vertebra was observed in 2 groups at 12 months, but showing no significant difference (P>0.05). ConclusionCompared with cross segment pedicle instrumentation, short-segment pedicle screw instrumentation with bone grafting and pedicle screw implanting in injured vertebra can recover and maintain the affected vertebra height in treating thoracolumbar fractures, but it could not effectively prevent degeneration of adjacent segments and the loss of kyphosis correction degree.
Objective To explore some operative problems of correcting paralytic scoliosis(PS) by using vertebral pedicle screwsrods system. Methods From May 2000 to May 2005, 18 patients with PS were corrected by screwsrods system which were made of titanium alloy.There were 10 males and 8 females, aging from 11 to 26 years. The primary disease included poliomyelitis in 13 patients and myelodysplasia (MS) in 5 patients (2 cases for second correction) with scoliosis of an average 85° Cobb angle (55-125°). The pelvic obliquity was found in all patients with an average 24° angle (355°).Of the 18 patients,3 cases were given perioperative halo-pelvic traction, 2 cases were given vertebral wedge osteotomy and correction and fixation, the other patients were purely underwent the treatment of pedicle screwrods system implants. Fusion segment at operation ranged from 6 to 15 sections, applied screws the most was 16,the fewest was 6. Results There were no wound infections and neurologic complications, all wounds healed by the first intention. Allscoliosis obtained obvious correction (P＜0.001), the correction rate averaged 52.95% (44%-81%); the majority of lumbar kyphosis and pelvic obliquity were apparently corrected. The average clinical follow-up (16 cases) was 21 months(6-36 months),there was no implants failure. One patient with MS had a worse Cobb magnitude, the other patients had no curve progression (P＞0.05). Conclusion The use of vertebral pedicle screwsrods fixation to multiple vertebral bodys and short segment fusion for PS, the treatment method is reliable and the outcome is satisfactory. While performing the correcting operative procedures, the spinal, pelvic and lower extremity deformities and functions should be all considered as a whole.
Objective To evaluate the biomechanical stability of a newly-designed Y type pedicle screw (YPS) in osteoporotic synthetic bone. Methods The osteoporotic synthetic bone were randomly divided into 3 groups (n=20). A pilot hole, 3.0 mm in diameter and 30.0 mm in deep, was prepared in these bones with the same method. The YPS, expansive pedicle screw (EPS), and bone cement-injectable cannulated pedicle screw (CICPS) were inserted into these synthetic bone through the pilot hole prepared. X-ray film examination was performed after 12 hours; the biomechanical stability of YPS, EPS, and CICPS groups was tested by the universal testing machine (E10000). The test items included the maximum axial pullout force, the maximum running torque, and the maximum periodical anti-bending. Results X-ray examination showed that in YPS group, the main screw and the core pin were wrapped around the polyurethane material, the core pin was formed from the lower 1/3 of the main screw and formed an angle of 15° with the main screw, and the lowest point of the inserted middle core pin was positioned at the same level with the main screw; in EPS group, the tip of EPS expanded markedly and formed a claw-like structure; in CICPS group, the bone cement was mainly distributed in the front of the screw and was dispersed in the trabecular bone to form a stable screw-bone cement-trabecular complex. The maximum axial pullout force of YPS, EPS, and CICPS groups was (98.43±8.26), (77.41±11.41), and (186.43±23.23) N, respectively; the maximum running torque was (1.42±0.33), (0.96±0.37), and (2.27±0.39) N/m, respectively; and the maximum periodical anti-bending was (67.49±3.02), (66.03±2.88), and (143.48±4.73) N, respectively. The above indexes in CICPS group were significantly higher than those in YPS group and EPS group (P<0.05); the maximum axial pullout force and the maximum running torque in YPS group were significantly higher than those in EPS group (P<0.05), but there was no significant difference in the maximum periodical anti-bending between YPS group and EPS group (P>0.05). Conclusion Compared with EPS, YPS can effectively enhance the maximum axial pullout force and maximum rotation force in the module, which provides a new idea for the design of screws and the choice of different fixation methods under the condition of osteoporosis.
Objective To explore the clinical effect of PSIS-A robot-assisted percutaneous screw in the treatment of thoracolumbar fracture. Methods Patients with thoracolumbar fracture who were hospitalized in Mianyang Orthopedic Hospital between August 2022 and January 2024 and required percutaneous pedicle screw f ixation were selected. Patients were divided into robot group and free hand group by random number table. Operative time, intraoperative bleeding, intraoperative radiation dose and time, implant accuracy rate, small joint invasion rate, Visual Analogue Scale score for pain and other indexes were compared between the two groups. Results A total of 60 patients were included. Among them, there were 28 cases in the robot group and 32 cases in the free hand group. On the third day after surgery, the Visual Analogue Scale score of the robot group was better than that of the free hand group (P=0.003). Except for intraoperative bleeding and radiation frequency (P>0.05), the surgical time, average nail implantation time, and intraoperative radiation dose in the robot group were all lower than those in the free hand group (P<0.05). The accuracy and excellence rate of nail planting in the robot group were higher than those in the free hand group (94.6% vs. 84.9%; χ2=7.806, P=0.005). There was no statistically significant difference in the acceptable accuracy rate (96.4% vs. 91.1%; χ2=3.240, P=0.072) and the incidence of screw facet joint invasion (7.2% vs.14.1%; χ2=3.608, P=0.058) between the two groups. Conclusion The application of PSIS-A type robot assisted percutaneous minimally invasive pedicle screw fixation in the treatment of thoracolumbar fr actures is promising.
Objective To investigate the safety and accuracy of robot-assisted pedicle screw implantation in the adolescent idiopathic scoliosis (AIS) surgery. Methods The clinical data of 46 patients with AIS who were treated with orthopedics, bone graft fusion, and internal fixation via posterior approach between June 2018 and December 2019 were analyzed retrospectively. Among them, 22 cases were treated with robot-assisted pedicle screw implantation (robot group) and 24 cases with manual pedicle screw implantation without robot assistance (control group). There was no significant difference in gender, age, body mass index, Lenke classification, and preoperative Cobb angle of the main curve, pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The intraoperative blood loss, pedicle screw implantation time, intraoperative pedicle screw adjustment times, and VAS and JOA scores after operation were recorded. The Cobb angle of the main curve was measured on X-ray film and the spinal correction rate was calculated. The screw position and the accuracy of screw implantation were evaluated on CT images. Results The operation completed successfully in the two groups. The intraoperative blood loss, pedicle screw implantation time, and pedicle screw adjustment times in the robot group were significantly less than those in the control group (P<0.05). There was 1 case of poor wound healing in the robot group and 2 cases of mild nerve root injury and 2 cases of poor incision healing in the control group, and there was no significant difference in the incidence of complications between the two groups (P=0.667). All patients in the two groups were followed up 3-9 months (mean, 6.4 months). The VAS and JOA scores at last follow-up in the two groups were superior to those before operation (P<0.05), but there was no significant difference in the difference of pre- and post-operative scores between the two groups (P>0.05). The imaging review showed that 343 screws were implanted in the robot group and 374 screws in the control group. There were significant differences in pedicle screw implantation classification and accuracy between the two groups (89.5% vs 79.1%)(Z=?3.964, P=0.000; χ2=14.361, P=0.000). At last follow-up, the Cobb angles of the main curve in the two groups were significantly lower than those before operation (P<0.05), and there was significant difference in the difference of pre- and post-operative Cobb angles between the two groups (t=0.999, P=0.323). The spinal correction rateswere 79.82%±5.33% in the robot group and 79.62%±5.58% in the control group, showing no significant difference (t=0.120, P=0.905). Conclusion Compared with manual pedicle screw implantation, robot-assisted pedicle screw implantation in AIS surgery is safer, less invasive, and more accurate.
Objective To compare the effectiveness of spinal robot-assisted pedicle screw placement through different surgical approaches and to guide the clinical selection of appropriate robot-assisted surgical approaches. MethodsThe clinical data of 14 patients with thoracolumbar vertebral diseases who met the selection criteria between January 2023 and August 2023 were retrospectively analyzed, and all of them underwent pedicle screw placement under assistant of the Mazor X spinal surgery robot through different surgical approaches. The patients were divided into posterior median approach (PMA) group (n=6) and intermuscular approach (IMA) group (n=8) according to the surgical approaches, and there was no significant difference in age, gender, body mass index, disease type, and fixed segment between the two groups (P>0.05). The operation time, intraoperative blood loss, screw-related complications, and reoperation rate were recorded and compared between the two groups; the inclination angle of the screw, the distance between the screw and the midline, and the caudal inclination angle of the screw were measured based on X-ray films at immediate after operation. Results There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). There was no screw-related complication such as nerve injury in both groups, and no patients underwent secondary surgery. At immediate after operation, the inclination angle of the screw, the distance between the screw and the midline, and the caudal inclination angle of the screw in the IMA group were significantly greater than those in the PMA group (P<0.05). ConclusionThere are differences in the position and inclination angle of screws placed with robot-assisted surgery through different surgical approaches, which may be due to the obstruction of the screw path by soft tissues such as skin and muscles. When using spinal robot-assisted surgery, selecting the appropriate surgical approach for different diseases can make the treatment more reasonable and effective.
Objective To explore the clinical application value of the spinal robot-assisted surgical system in mild to moderate lumbar spondylolisthesis and evaluate the accuracy of its implantation. Methods The clinical data of 56 patients with Meyerding grade Ⅰ or Ⅱ lumbar spondylolisthesis who underwent minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) between January 2017 and December 2017 were retrospectively analysed. Among them, 28 cases were preoperatively planned with robotic arm and percutaneous pedicle screw placement according to preoperative planning (group A); the other 28 cases underwent fluoroscopy-guided percutaneous pedicle screw placement (group B). There was no significant difference in gender, age, body mass index, slippage type, Meyerding grade, and surgical segmental distribution between the two groups (P>0.05). The screw insertion angle was measured by CT, the accuracy of screw implantation was evaluated by Neo’s criteria, and the invasion of superior articular process was evaluated by Babu’s method. Results One hundred and twelve screws were implanted in the two groups respectively, 5 screws (4.5%) in group A and 26 screws (23.2%) in group B penetrated the lateral wall of pedicle, and the difference was significant (χ2=9.157, P=0.002); the accuracy of nail implantation was assessed according to Neo’s criteria, the results were 107 screws of degree 0, 3 of degree 1, 2 of degree 2 in group A, and 86 screws of degree 0, 16 of degree 1, 6 of degree 2, 4 of degree 3 in group B, showing significant difference between the two groups (Z=4.915, P=0.031). In group B, 20 (17.9%) screws penetrated the superior articular process, while in group A, 80 screws were removed from the decompression side, and only 3 (3.8%) screws penetrated the superior articular process. According to Babu’s method, the degree of screw penetration into the facet joint was assessed. The results were 77 screws of grade 0, 2 of grade 1, 1 of grade 2 in group A, and 92 screws of grade 0, 13 of grade 1, 4 of grade 2, 3 of grade 3 in group B, showing significant difference between the two groups (Z=7.814, P=0.029). The screw insertion angles of groups A and B were (23.5±6.6)° and (18.1±7.5)° respectively, showing significant difference (t=3.100, P=0.003). Conclusion Compared to fluoroscopy-guided percutaneous pedicle screw placement, robot-assisted percutaneous pedicle screw placement has the advantages such as greater accuracy, lower incidence of screw penetration of the pedicle wall and invasion of the facet joints, and has a better screw insertion angle. Combined with MIS-TLIF, robot-assisted percutaneous pedicle screw placement is an effective minimally invasive treatment for lumbar spondylolisthesis.
ObjectiveTo evaluate the clinical efficacy of domestic minimally-invasive percutaneous screw system for thoracolumbar fractures without neurological damage. MethodsSixty patients suffering from unstable thoracolumbar fractures without obvious neurologic deficits treated from January 2011 to April 2012 were studied retrospectively. The patients were divided into two groups:group A (domestic minimally-invasive percutaneous screw system) and group B (imported minimally-invasive percutaneous screw system). Perioperative parameter, pre-and post-operative imaging indexes, visual analog scale (VAS) and modified MacNab evaluation standard were studied for comparison. ResultsAll the patients were followed up from 6 to 18 months with an average of (12.2±3.0) months. The Cobb's angle and anterior height of the fracture vertebral body changed significantly in each group (P<0.05). There was no significant difference in incision size, surgical time, postoperative improvement of Cobb's angle, anterior height of the fracture vertebral body and accuracy of pedicle screw placement between the two groups (P>0.05). ConclusionDomestic minimally-invasive percutaneous screw system is reliable with minimal invasion, which is comparable to imported minimally-invasive percutaneous screw system.
Objective To investigate the application value of intraoperative CT navigation in posterior thoracic pedicle screw placement for scoliosis patients. Methods Between October 2009 and December 2011, 46 patients with scoliosis were treated with thoracic pedicle screw placement under intraoperative CT navigation in 21 cases (group A) or under C-arm fluoroscopy in 25 cases (group B). There was no significant difference in age, gender, type of scoliosis, involved segment, and Cobb angle of main thoracic curve between 2 groups (P gt; 0.05). A total of 273 thoracic pedicle screws were placed in group A and 308 screws in group B. The pedicle screw position evaluated and classified by intraoperative CT images according to the Modi et al. method; and the accurate rate, the safe rate, and the potential risk rate of pedicle screws were calculated on the upper thoracic spine (T1-4), the middle thoracic spine (T5-8), the lower thoracic spine (T9-12), and the entire thoracic spine (T1-12). The accuracy and security of thoracic pedicle screw placement were compared between 2 groups. Results On the entire thoracic spine, the accurate rate of group A (93.4%) was significantly higher than that of group B (83.8%), the safe rate of group A (98.9%) was significantly higher than that of group B (92.5%), showing significant differences between 2 groups (P lt; 0.05). However, the potential risk rate of group B (7.5%) was significantly higher than that of group A (1.1%) (P lt; 0.05). On the upper, the middle, and the lower thoracic spines, there was no significant difference in the accurate rate, the safe rate, and the potential risk rate of pedicle screws between 2 groups (P gt; 0.05). According to CT evaluation results, the potential risk pedicle screws were revised or removed during operation. The patients of 2 groups had no neurological deficits through physical examination of nervous system at 3 days after operation. Conclusion Intraoperative CT navigation can improve the accuracy and security of posterior thoracic pedicle screw placement and it can ensure the safety of operation by finding and promptly removing or revising the potential risk pedicle screws.