Objective To investigate the effectiveness of computer-assisted and robot-assisted atlantoaxial pedicle screw implantation for the treatment of reversible atlantoaxial dislocation (AAD). MethodsThe clinical data of 42 patients with reversible AAD admitted between January 2020 and June 2023 and met the selection criteria were retrospectively analyzed, of whom 23 patients were treated with computer-assisted surgery (computer group) and 19 patients were treated with Mazor X spinal robot-assisted surgery (robot group). There was no significant difference in gender, age, T value of bone mineral density, body mass index, etiology, and preoperative Japanese Orthopaedic Association (JOA) score, Neck Dysfunction Index (NDI) between the two groups (P>0.05). The operation time, screw implantation time, intraoperative blood loss, hand and wrist radiation exposure, and complications were recorded and compared between the two groups. Gertzbein classification was used to evaluate the accuracy of screw implantation. JOA score and NDI were used to evaluate the function before operation, at 3 days after operation, and at last follow-up. At last follow-up, the status of screws and bone fusion were observed by neck three-dimensional CT. Results The operation time and hand and wrist radiation exposure of the computer group were significantly longer than those of the robot group (P<0.05), and there was no significant difference in the screw implantation time and intraoperative blood loss between the two groups (P>0.05). All patients were followed up 11-24 months, with an average of 19.6 months. There was no significant difference in the follow-up time between the two groups (P>0.05). There was no significant difference in the accuracy of screw implantation between the two groups (P>0.05). Except for 1 case of incision infection in the computer group, which improved after antibiotic treatment, there was no complication such as nerve and vertebral artery injury, screw loosening, or breakage in the two groups. The JOA score and NDI significantly improved in both groups at 3 days after operation and at last follow-up (P<0.05) compared to those before operation, but there was no significant difference between the two groups (P>0.05). At last follow-up, 21 patients (91.3%) in the computer group and 18 patients (94.7%) in the robot group achieved satisfactory atlantoaxial fusion, and there was no significant difference in the fusion rate between the two groups (P>0.05). ConclusionComputer-assisted or robot-assisted atlantoaxial pedicle screw implantation is safe and effective, and robotic navigation shortens operation time and reduces radiation exposure.
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 compare the effectiveness of percutaneous short-segment injured vertebra pedicle screw fixation combined with bone grafting versus percutaneous short-segment injured vertebra pedicle screw fixation alone for the treatment of thoracolumbar fractures. Methods The clinical data of 54 patients with single-level thoracolumbar fractures who met the selection criteria between January 2023 and February 2024 were retrospectively analysed. Based on whether bone grafting was performed on the injured vertebra, the patients were divided into a control group (28 cases, percutaneous short-segment injured vertebra pedicle screw fixation alone) and a study group (26 cases, percutaneous short-segment injured vertebra pedicle screw fixation combined with bone grafting using a self-made minimally invasive bone grafting funnel). No significant difference was observed between the two groups (P>0.05) in baseline data, including age, gender, surgical segment, cause of injury, AO classification, and preoperative anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, visual analogue scale (VAS) score, and Oswestry Disability Index (ODI). The operation time, intraoperative blood loss, fracture healing status, removal time of internal fixator, and complications were recorded and compared between the two groups. Effectiveness was assessed using anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, VAS scores, and ODI taken preoperatively, at 1 week postoperatively, and at last follow-up. ResultsAll patients in both groups successfully underwent surgery. The operation time and intraoperative blood loss in the control group were significantly less than those in the study group (P<0.05). No significant difference was observed in the follow-up time between the study group [(14.46±2.00) months] and control group [(14.36±1.83) months] (P>0.05). The fracture healing time of the study group was significantly shorter than that of the control group (P<0.05). One patient in the study group was found to have bilateral titanium rod breakage by X-ray reexamination at 8 months after operation, and there was no subsequent vertebral height collapse occurred, and the internal fixator was removed following complete fracture healing. The other patients had no complication such as spinal cord injury, internal fixator loosening and breakage. There was no significant difference in the removal time of internal fixator between the two groups (P<0.05). The anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, VAS score, and ODI significantly improved in both groups at 1 week after operation and at last follow-up (P<0.05). Among them, the VAS score, and ODI further improved at last follow-up when compared with at 1 week after operation, Cobb angle lost a little at 1 week after operation, while anterior-vertebral height compression ratio and mid-vertebral height compression ratio slightly increased when compared with 1 week after operation, and the differences were significant (P<0.05). There was no significant difference between the two groups in Cobb angle at last follow-up, VAS score and ODI at 1 week after operation (P>0.05), while the other indicators in the study group were significantly better than those in the control group at all time points (P<0.05). Conclusion Compared to percutaneous short-segment injured vertebra pedicle screw fixation alone, the technique combined with intravertebral bone grafting can shorten fracture healing time, effectively restore and maintain vertebral body height, correct kyphotic deformity, and improve clinical outcomes for patients with thoracolumbar fractures.
Objective To evaluate the therapeutic effects of expandable pedicle screw (EPS) combined with interbody fusion cage on lumbar spondylolisthesis. Methods From June 2004 to March 2008, 23 patients with lumbar spondylolisthesiswere treated, including 9 males and 14 females aged 24-72 years old (average 48.7 years old). The course of the disease varied from 6 months to 6 years (average 30.4 months). There were 18 cases of degenerative spondylol isthesis and 5 of isthmic spondylolisthesis, including 1 case at L3,4 level, 14 at L4,5 level, and 8 at L5 and S1 levels. There were 17 cases of grade I, 4 of grade II, and 2 of grade III (including 1 case of recurrent L5 spondylolysis) according to Meyerding classification system. Posterior lumbar interbody fusion was performed using 48 PLIVIOS interbody fusion cages, and spondylolisthesis reduction and internal fixation were conducted using 84 pieces of EPS. The indications for use of EPS were initial operation with bone mass reduction or osteoporosis, reoperation of previous pedicle instrumentation, intraoperative screw relocation, sacral anchoring, and construct reinforcement. Cl inical outcomes, radiographic reduction of spondylol isthesis and bone fusion of lumbar interbody were evaluated based on JOA score, Boxall index, and Cook criteria. Results The incision healed by first intension in all cases except for one revision case that suffered from postoperative cerebrospinal fluid leakage and obtained delayed-healing without infection 23 days after operation using conservative treatment. No operative compl ications such as nerve and organ injuries were found.All cases were followed up for 12-39 months (average 17.8 months). X-ray exams of spine AP, lateral, fully extended position and fully flexed position view showed all 84 EPS were fully expanded within vertebral body. The improvement rate of JOA at the final follow-up visit was markedly effective in 14 cases, and effective in 5 cases, and noneffective in 4 cases, with a total effective rate of 82.61%. Anatomic reduction was achieved in 14 cases, improvement was obtained in 6 cases, no improvement was observed in 3 cases, and the reduction rate was 86.69%. Lumber interbody fusion was achieved in 20 cases, fixation was achieved in 2 cases, failure was observed in 1 cases, and the fusion rate was 86.69%. Conclusion EPS in complex with interbody fusion cage provides effective reduction, internal fixation and interbody fusion for the reconstruction of lumbar spondylolisthesis.
Objective To investigate the effectiveness of injured vertebra fixation with inclined-long pedicle screws combined with interbody fusion for thoracolumbar fracture dislocation with disc injury. Methods Between January 2017 and June 2022, 28 patients with thoracolumbar fracture dislocation with disc injury were underwent posterior depression, the injured vertebra fixation with inclined-long pedicle screws, and interbody fusion. There were 22 males and 6 females, with a mean age of 41.4 years (range, 22-58 years). The causes of injury included falling from height in 18 cases, traffic accident in 5 cases, and bruise in 5 cases. Fracture segment included 1 case of T11, 7 cases of T12, 9 cases of L1, and 11 cases of L2. According to the American Spinal Injury Association (ASIA) scale, the spinal injuries were graded as grade A in 4 cases, grade B in 2 cases, grade C in 11 cases, and grade D in 11 cases. Preoperative spinal canal encroachment ratio was 17.7%-75.3% (mean, 44.0%); the thoracolumbar injury classification and severity score (TLICS) ranged from 9 to 10 (mean, 9.9). Seventeen patients were associated with other injuries. The time from injury to operation ranged from 1 to 4 days (mean, 2.3 days). The perioperative indicators (operation time, intraoperative blood loss, and the occurrence of complications), clinical evaluation indicators [visual analogue scale (VAS) score and Oswestry Disability Index (ODI)], radiologic evaluation indicators [anterior vertebral height ratio (AVHR), kyphosis Cobb angle (KCA), intervertebral space height (ISH), vertebral wedge angle (VWA), displacement angle (DA), and percent fracture dislocation displacement (PFDD)], neurological function, and interbody fusion were recorded. Results The operation time was 110-159 minutes (mean, 130.2 minutes). The intraoperative blood loss was 200-510 mL (mean, 354.3 mL). All incisions healed by first intention, and no surgical complications such as wound infection or hematoma occurred. All patients were followed up 12-15 months (mean, 12.7 months). The chest and lumbar pain significantly relieved, VAS scores and ODI after operation were significantly lower than those before operation, and further decreased with the extension of postoperative time, with significant differences (P<0.05). At last follow-up, the ASIA classification of neurological function of the patients was grade A in 3 cases, grade B in 1 case, grade C in 1 case, grade D in 10 cases, and grade E in 13 cases, which was significantly different from preoperative one (Z=?4.772, P<0.001). Imaging review showed that AVHR, KCA, ISH, VWA, DA, and PFDD significantly improved at 1 week, 3 months and last follow-up (P<0.05). There was no significant difference between different time points after operation (P>0.05). At last follow-up, according to the modified Brantigan score, all patients achieved good intervertebral bone fusion, including 22 complete fusion and 6 good intervertebral fusion with a few clear lines. No complications such as internal fixation failure or kyphosis occurred during follow-up.Conclusion The injured vertebra fixation with inclined-long pedicle screws combined with interbody fusion is an effective treatment for thoracolumbar fracture dislocation with disc injury, which can correct the fracture dislocation, release the nerve compression, restore the injured vertebral height, and reconstruct spinal stabilization.
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 investigate the accuracy of progressive three-dimensional navigation template system (abbreviated as progressive template) to assist atlas-axial pedicle screw placement. MethodsThe clinical data of 33 patients with atlas-axial posterior internal fixation surgery between May 2015 and May 2017 were retrospectively analyzed. According to the different methods of auxiliary screw placement, the patients were divided into trial group (19 cases, screw placement assisted by progressive template) and control group (14 cases, screw placement assisted by single navigation template system, abbreviated as initial navigation template). There was no significant difference in gender, age, cause of injury, damage segments, damage types, and preoperative Frankel classification between the two groups (P>0.05). The operation time and intraoperative blood loss of the two groups were compared. The safety of screw placement was evaluated on postoperative CT by using the method from Kawaguchi et al, the deviation of screw insertion point were calculated, the angular deviation of the nailing on coordinate systems XOZ, XOY, YOZ were calculated according to Peng’s method. ResultsAll patients completed the operation successfully; the operation time and intraoperative blood loss in the trial group were significantly less than those in the control group (t=–2.360, P=0.022; t=–3.006, P=0.004). All patients were followed up 12–40 months (mean, 25.3 months). There was no significant vascular injury or nerve injury aggravation. Postoperative immediate X-ray film and CT showed the dislocation was corrected. Postoperative immediate CT showed that all 76 screws were of grade 0 in the trial group, and the safety of screw placement was 100%; 51 screws were of grade 0, 3 of gradeⅠ, and 2 of gradeⅡ in the control group, and the safety of screw placement was 91.1%; there was significant difference in safety of screw placement between the two groups (χ2=7.050, P=0.030). The screw insertion point deviation and angular deviation of the nailing on XOY and YOZ planes in the trial group were significantly less than those in the control group (P<0.05). There was no significant difference in angular deviation of the nailing on XOZ between the two groups (t=1.060, P=0.290). ConclusionCompared with the initial navigation template, the progressive navigation template assisting atlas-axial pedicle screw placement to treat atlas-axial fracture with dislocation, can reduce operation time and intraoperative blood loss, improve the safety of screw placement, and match the preoperative design more accurately.
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.
Objective To investigate the influence of axis pedicle and intra-axial vertebral artery (IAVA) alignment on C2 pedicle screw placement by measuring the data of head and neck CT angiography. MethodsThe axis pedicle diameter (D), isthmus height (H), isthmus thickness (T), and IAVA alignment types were measured in 116 patients (232 sides) who underwent head and neck CT angiography examinations between January 2020 and June 2020. Defined the IAVA offset direction by referencing the vertical line through the center of C3 transverse foramen on the coronal scan, it was divided into lateral (L), neutral (N), and medial (M). Defined the IAVA high-riding degree by referencing the horizontal line through the outlet of the C2 transverse foramen, it was divided into below (B), within (W), and above (A). The rate of pedicle stenosis, high-riding vertebral artery, and different IAVA types were calculated, and their relationships were analysed. Simulative C2 pedicle screws were implanted by Mimics 19.0 software, and the interrelation among the rates of pedicle stenosis, high-riding vertebral artery, IAVA types, and vertebral artery injury were analyzed. ResultsThe rate of C2 pedicle stenosis was 33.6% (78/232), and the rate of high-riding vertebral artery was 35.3% (82/232). According to the offset direction and the degree of riding, IAVA was divided into 9 types, among which the N-W type (29.3%) was the most, followed by the L-W type (19.0%) and the L-B type (12.9%), accounting for 60.9%. The vertebral artery injury rate of simulative implanted C2 pedicle screws was 35.3% (82/232). The vertebral artery injury rate in patients with pedicle stenosis and high-riding vertebral artery was significantly higher than that who were not (P<0.001). The rate of pedicle stenosis, high-riding vertebral artery, and vertebral artery injury were significantly different among IAVA types (P<0.001), and M-A type was the most common. ConclusionVertebral artery injury is more common in pedicle stenosis and/or high-riding vertebral artery and/or IAVA M-A type. Preoperative head and neck CT angiography examination has clinical guiding significance.
ObjectiveTo investigate the effectiveness of cervical pedicle screw implantation technique under regional method.MethodsThe clinical data of 85 patients who met the selection criteria between April 2010 and May 2018 were retrospectively analyzed. There were 57 males and 28 females, aged 35-68 years, with an average of 57.6 years. Among them, there were 10 cases of ossification of posterior longitudinal ligament, 68 cases of cervical spondylosis with multilevel stenosis, 3 cases of cervical tumor, 1 case of congenital malformation, and 3 cases of cervical trauma; the lower cervical spine lesions involved C3-C7. Preoperative Frankel spinal cord injury grading: 2 cases of grade C, 51 cases of grade D, and 32 cases of grade E. Cervical pedicle screw implantation technique under regional method was performed with a total of 618 pedicle screws. Postoperative changes in neurological symptoms were observed; cervical mouth opening anteroposterior and lateral X-ray films and cervical CT examinations were performed to evaluate the pedicle screws position.ResultsThe operation time was 2.5-4.0 hours, with an average of 3.0 hours. The intraoperative blood loss was 180-550 mL, with an average of 345 mL. No intraoperative vascular or nerve injury occurred. The patients with neurological symptoms were relieved to varying degrees. There were 2 cases of superficial incision infection after operation, the wound healed after enhanced dressing change. The postoperative hospital stay was 5-14 days, with an average of 8.4 days. At discharge, Frankel neurological grading was grade D in 26 patients and grade E in 59 patients. All the patients were followed up 6-24 months, with an average of 13 months. At last follow-up, cervical X-ray films showed the good pedicle screw fixation without loosening. Cervical CT evaluated the position of pedicle screws: 523 pedicle screws (84.7%) in grade Ⅰ, 80 (12.9%) in grade Ⅱ, and 15 (2.4%) in grade Ⅲ; the accuracy rate of the screw position was 97.6%.ConclusionCervical pedicle screw implantation technique under regional method can significantly improve the success rate of screw implantation. It is easy to operate, does not destroy the bone cortex, and has stable fixation.