ObjectiveTo re-evaluate the systematic review and meta-analysis (SR/MAs) of the efficacy of robot-assisted pedicle screw placement. MethodsThe CNKI, VIP, WanFang Data, SinoMed, PubMed, Embase, Cochrane Library, and Web of Science databases were electronically searched to collect SR/MAs of robot-assisted pedicle screw placement from inception to April 28, 2023. Two reviewers independently screened literature, extracted data and then assessed the quality of reports, methodological quality, risk of bias, and the strength of evidence quality by using PRISMA, AMSTAR-Ⅱ, ROBIS, and GRADE tool. ResultsA total of 20 SR/MAs were included. The results of the included studies showed that robot-assisted pedicle screw placement was more accurate and had a lower number of complications compared with freehand pedicle screw placement. The quality of reports, methodology, and evidence for pedicle screw placement efficiency in all SR/MAs were low or extremely low, with a high risk of bias. The main reasons included high heterogeneity of included studies, unclear research methods and selection criteria, and missing key reporting processes. ConclusionRobot-assisted pedicle screw placement may have better clinical efficiency than traditional freehand pedicle screw placement. But the quality of relational SR/MAs is low.
Objective To ascertain whether augmentation pedicle screw fixation with polymethylmethacrylate (PMMA) can enhance the stability of unstable thoracolumbar burst fractures of osteoporotic spine. Methods Six fresh frozen female osteoporotic spines (T10-L5) were harvested and an anterior and posterior columnunstable model of L1 was made. Each specimen was fixated with plate and the stability test were performed by flexion, extension, axial rotation and lateral bending. The test of fatigue was done with MTS 858.The tests were repeated after screws were augmented with PMMA. To compare the biomechanical stability of 6 different conditions:○anormal specimens(control), ○bdefectmodel fixed with plate, not augmented and not fatigued, ○cafter fatigued, not augmented, ○dscrews augmented with PMMA, not fatigued, ○e after augmented and fatigued. ResultsIn ○b,○d and ○e conditions, the ranges of motion(ROM) were 6.23±1.56，4.49±1.00，4.46±1.83 inflexion and 6.60±1.80，4.41±0.82，4.46±1.83 in extension. There was no significant difference (Pgt;0.05), they were significantly smaller than those in ○a and ○c conditions (8.75±1.88，1.47±2.25 and 8.92±2.97，12.24±3.08) (Plt;0.01).Conclusion The results demonstrated that augmentation pedicle screws fixation with PMMA can increase the stability of osteoporotic spine.
Objective To develop a high-accuracy, better-safety and low-cost cervical pedicle locator system for guiding cervical pedicle screw placement. Methods Cervical pedicle screw locator system was made of stainless steel. Ten cervical specimens from voluntary donation were divided into two groups according to compatibil ity design: control group inwhich 60 screws were planted into C2-7 by free hand; and experimental group in which 60 screws were planted into C2-7 under the guidance of three-dimensional locator system. The condition of screw insertion was observed and the accuracy was evaluated by the integrity of pedicle walls. Results In the control group, 32 screws (53.33%) were placed inside the pedicles and 28 (46.67%) were outside; 9 screws (15.00%) led to nerve root injury, 5 screws (8.33%) caused vertebral artery injury and no spinal cord injury occurred; and the qual ification ratio of screw insertion was 76.67% (excellent 32, fair 14, poor 14). While in the experimental group, 54 screws (90.00%) were placed inside the pedicles and 6 (10.00%) were outside; 1 screw (1.67%) caused vertebral artery injury and no nerve root injury and spinal cord injury occurred; and the qual ification ratio of screw insertion was 98.33% (excellent 54, fair 5, poor 1). There was significant difference between the two groups (P lt; 0.05). Conclusion Cervical pedicle screw locator system has the advantages of easy manipulation, high accuracy of screw placement and low cost. With further study, it can be appl ied to the cl inical.
OBJECTIVE: To review the anatomic character of lower cervical pedicle, the placement and the biomechanical stability of the cervical pedicle screw fixation, the clinical application and the complication caused by fixation. METHODS: The literature concerned the cervical pedicle screw fixation in recent years were extensively reviewed. RESULTS: The cervical pedicle screw fixation can be widely used in the lower cervical spine instability according to the anatomic character of lower cervical pedicle, and the good biomechanical stability of the cervical pedicle screw fixation, and the complication can be controlled. CONCLUSION: The cervical pedicle screw fixation is an effective internal fixation for the lower cervical spine instability.
Objective To assess the outcomes of pedicle subtration osteotomy and short-segment pedicle screw internal fixation in kyphosisdeformity. Methods From June 2001 to November 2003, 16 cases of kyphosis deformity were treated with pedicle subtration osteotomy and short-segment pedicle screw internal fixation, including 11 males and 5 females and aging 24-51 years. The kyphosis deformity was caused by ankylosing spondylitis in 12 cases, old lumbothoracic fracturedislocation in 2 cases, and vertebral dysplasia in 2 cases. The disease course was 7-25 years with an average of 12.8years. The whole spine radiographs were taken pre-and postoperatively. The sagittal balance was assessed by measuring thoracic kyphosis angle, lumbar lordosis angle, acrohorizontal angle and distance between posterosuperior point of S1and the vertical line. The clinical outcomes were assessed by Bridwell-Dewald scale for spinal disorders. Results The mean follow-up period was25.6 months. The mean bleeding was 1 100 ml. Satisfactory bone graft healing was achieved at final follow-up. Complications were paralytic intestinal obstruction in 1 case, dura laceration in 1 case, and temporary lower limb paralysis in 2 cases. Final follow-up radiograph showed an increase in lumbar lordosis angle from 9.6±16.4° to 42.6±14.3°(P＜0.05), whereas thoracic kyphosis angle remained relative stable. The distance between posterosuperior point of S1 and the vertical line was decreased from 97.5±45.6 mm to 10.7±9.6 mm(P＜0.05). Satisfactory clinical outcome was achieved by evaluating the changes of pain, social and working status. Conclusion Pedicle subtraction osteotomy and short-segment pedicle screw internal fixation is effective for correction of kyphosis deformity.
Objective To assess the cl inical significance of transpedicular screw insertion in lower cervical vertebra assisted by multi-spiral CT (MSCT) three dimentional (3D) image reconstruction techniques. Methods Eight cervical vertebra specimens were examined by MSCT, and the messages were sent to SGI02 Workstation; according to the parameter requirements of lower cervical pedicle fixation, by using post-process of volume rendering (VR) the condition was judged and multi-plannar reformation (MPR) was used to do individual analysis; and the ideal path of screw insertion was obtained andthe related parameters were measured. After preoperative plan being finished, referring to these measured parameters, 3.5 mm screws were inserted into C3-7 pedicles of these 8 specimens. After insertion of screws, MSCT scanning and 3D reconstruction were performed again to evaluate the accuracy of lower cervical pedicle screw inserting. From May 2007 to November 2009, 28 patients who received screw insertion in lower cervical spines were given MSCT scanning and 3D reconstruction to evaluate the illness situation, to confirm shortest fixation volumes, and to collect the parameters of aim pedicle screw insertion. Results The time of insertion for each screw was (392 ± 62) seconds. It was found that one pedicle was clausura (1.25%, 1/80) and five pedicle diameters in coronal view were less than 3 mm (6.25%, 5/80), which all were not fit for screw insertion. A total of 74 screws were placed successfully. One-time success rate of screw insertion was 95.95% (71/74). The total accuracy rate was 91.89% (68/74). Six screws penetrated (8.11%). According to the Richter penetrating classification: grade one was 6.76% (5/74) and grade two was 1.35% (1/74). There were significant differences (P lt; 0.05) in penetrated rate between our study and anatomic landmark local ization (47.37%), Miller methods (25.00%), and there was no significant difference (P gt; 0.05) when compared with Abumi method (6.70%), hopper method (7.10%), pipel ine deoppilation method (5.20%) and navigation technique (11.30%). In cl inical 28 cases, 121 screws were inserted; one pedicle was clausura and one was fissure fracture, which all were unfit for insert screw in preoperative plan, the surgery project was adjusted. After operation, 17 patients (76 screws) were given MSCT scanning again. A total of 67 screws (88.16%) were placed successfully. Nine screws (11.84%) penetrated, grade one was 7.89% (6/76) and grade two was 3.95% (3/76). Conclusion It is accurate to apply MSCT 3D reconstruction techniques to measure the ideal screw canal in preoperative individual ized plan. Strictly following individual quantitative data, the safety and accuracy of the surgery can be improved. And it is feasible and available to use MSCT MPR imaging to evaluate the accuracy of pedicle screw insertion.
Objective To investigate the classification of atlas pedicles and the methods of the pedicle screw fixation. Methods To study the classification of atlas pedicles, 48 dry adult atlas specimens were measured. By atlas 3D-CT reconstruction, two transverse sections were establ ished by going through the one third of the lateral atlas pedicle and 2 mmbelow the vertebral artery sulcus. By setting 3.50 mm and 1.75 mm as the standardized diameter and radius for the screwand according to the thickness of bone substance of vertebral artery sulcus that went through the one third of the lateralatlas pedicle, the anatomical morphology of atlas pedicles were classified into three types: general type with 40 specimens (83%), l ight variation type with 6 specimens (13%), and severe variation type with 2 specimens (4%). The entry pathway was confirmed by the intersection l ine of the two transverse sections that went through the lateral one third of the atlas pedicle and 2 mm below the vertebral artery sulcus. The project-point of the entry pathway on the atlas posterior arch was considered to be the entry point. Forty-eight dry atlas specimens were used to measure the following relevant anatomic data with an electronic cal iper: the distance between the entry point and the posterior margin of the lateral mass (L1), the height of atlas pedicle at the entry point (L2), the vertical distance between the entry point and the inferior articular facet of the lateral mass (L3), the mass height at the entry point (L4), the mass width at the entry point (L5), the width of the atlas pedicle at the entry point (L6), the thickness of the pedicle under the vertebral artery sulcus at the entry pathway (H1). To research the method of the pedicle screw fixation, 12 fresh-frozen adult atlas specimens were adopted to simulate the fixation of the pedicle screw. The thickness of the bone substance of vertebral artery sulcus on both the left and the right sides of the pathway was grinded into 3 types: 1.5 mm and 2.5 mm, 1.5 mm and 4.0 mm, 2.5 mm and 4.0 mm, and each type had four specimens. The entry pathway was confirmed by the intersection l ine of two transverse sections that went through the lateral one third of atlas pedicle and 2 mm below the vertebral artery sulcus. Results On the left side, L1 was (5.79 ± 1.24) mm, L2 (4.55 ± 1.29) mm, L3 (5.12 ± 1.06) mm, L4 (12.43 ± 1.01) mm, L5 (12.66 ± 1.37) mm, L6 (7.86 ± 0.77) mm, and H1 (4.11 ± 1.25) mm. On the right side, L1 was (5.81 ± 1.26) mm, L2 (4.49 ± 1.22) mm, L3 (5.15 ± 1.05) mm, L4 (12.49 ± 0.98) mm, L5 (12.65 ± 1.38) mm, L6 (7.84 ± 0.78) mm, and H1 (4.13 ± 1.29) mm. There was no significant difference between the two sides (P gt; 0.05). After simulation of inserting screws, no screw in the specimens was found to break the bone substance in the sulcus of vertebral artery. Conclusion For the pedicle screw fixation of those patients whose atlas posterior arches are not high enough, we might partly drill through or beyond the atlas posterior arch. The entry point should be ascertained by preoperative 3D-CT reconstruction and intra-operative exploration.
Objective To investigate short-term effectiveness of spinal navigation with the intra-operative three-dimensional (3D)-imaging modality in pedicle screw fixation for congenital scoliosis (CS). Methods Between July 2010 and December 2011, 26 patients with CS were treated. Of 26 patients, 13 patients underwent pedicle screw fixation using the spinal navigation with the intra-operative 3D-imaging modality (navigation group), while 13 patients underwent the conventional technique with C-arm X-ray machine (control group). There was no significant difference in gender, age, hemivertebra number and location, major curve Cobb angle, and Risser grade between 2 groups (P gt; 0.05). Operation time, operative blood loss, frequency of the screw re-insertion, and postoperative complication were observed. The pedicle screw position was assessed by CT postoperatively with the Richter’s standard and the correction of Cobb angle was assessed by X-ray films. Results All patients underwent the surgery successfully without major neurovascular complication. There was no significant difference in operation time, operative blood loss, and pedicle screw location between 2 groups (P gt; 0.05). A total of 58 screws were inserted in navigation group, and 3 screws (5.2%) were re-inserted. A total of 60 screws were inserted in control group, and 10 screws (16.7%) were re-inserted. There was significant difference in the rate of pedicle screw re-insertion between 2 groups (χ2=3.975, P=0.046). Patients of navigation group were followed up 6-24 months, and 6-23 months in control group. According to Richter’s standard, the results were excellent in 52 screws and good in 6 screws in navigation group; the results were excellent in 51 screws, good in 5 screws, and poor in 4 screws in control group. Significant difference was found in the pedicle screw position between 2 groups (Z= — 1.992, P=0.046). The major curve Cobb angle of 2 groups at 1 week and last follow-up were significantly improved when compared with preoperative value (P lt; 0.05), but there was no significant difference between 1 week and last follow-up (P gt; 0.05). No significant difference in correction rate of the major curve Cobb angle was found between 2 groups at last follow-up (t=0.055, P=0.957). Conclusion Spinal navigation with the intra-operative 3D-imaging modality can improve the accuracy of pedicle screw implantation in patients with CS, and effectually reduce the rate of screw re-insertion, and the short-term effectiveness is satisfactory.
ObjectiveTo explore the application value of thin CT angiography (CTA) of pedicle sagittal plane of axis for preoperative evaluation planning pedicle screw placement.MethodsBetween February 2016 and August 2017, 34 patients (68 pedicles) who underwent thin CTA scan before posterior axial surgery were retrospectively analyzed. The vertebral artery development was statistically analyzed. The continuous layers of transverse process hole pedicle height more than or equal to 4 mm (f) were measured and read. The axial fixation methods, clinical manifestations of vertebral artery and spinal cord injury and the bone union of fractures or implants were recorded. Postoperative results of pedicle screws were evaluated by CT scan.ResultsThe right sides of 8 cases and the left sides of 18 cases were dominant vertebral arteries, and equilibrium was reached in 8 cases; f>9 layers were found in 16 pedicles,f=9 layers in 27 pedicles, f=8 layers in 17 pedicles, and f<8 layers in 8 pedicles. The 43 pedicles off≥9 layers used pedicle screw fixation; in the 17 pedicles of f=8 layers, 16 used pedicle screw fixation, and the other one used laminar screw fixation; in the 8 pedicles of f<8 layers, 4 used pedicle screw fixation, and the other 4 used laminar screw fixation. A self-defined pedicle screw grading system was used to evaluate the excellence, and the result showed that,f>9 layers: 14 pedicles were class A, 2 were class B, none was class C;f=9 layers: 16 pedicles were class A, 7 were class B, 4 were class C; f=8 layers: 3 pedicles were class A, 5 were class B, 8 were class C; f<8 layers: none was pedicles class A or class B, 4 were class C. The other 4 lamina screws fixation didn’'t invade the spinal canal. One case of pedicle class C showed clinical manifestations of mild dizziness and drowsiness. The patients were followed up for 6-11 months with an average of (8±3) months, and the fracture or bone graft fusion were observed after 6 months of following-up.ConclusionBased on preoperative CTA thin layer scanning, through measuring and reading continuous layers of transverse process hole pedicle height more than or equal to 4 mm, can effectively judge the security of axial pedicle screws in order to subsequently choose the reasonable operation methods so as to improve success rate and decrease surgical risk.
Objective To evaluate the accuracy of pedicle guide device for the placement of the pedicle screws. Methods Pedicle guide device was designed and made for the anatomical trait of pedicle. The 3-Danatomical data of the thoracic pedicles were measured by multislice spiral CT in two embalmed human cadaveric thoracic pedicles spine(T1 -T10). Depending on transverse section angle(TSA) and sagittal section angle(SSA) of pedicle axis, the degree of horizontal dial and sagittal dial were adjusted in the guide device. The screws wereinserted bilaterally in the thoracic pedicles by using the device. After pulling the screws out, the pathways were filled with contrast media. The TSA and SSA of developed pathways were measured. Results Analysis of the difference between pedicle axis and developed pathway was of no statistical significance(P＞0.05). Conclusion The guide device could be easilyoperated and guarantee high accuracy of the pathways of screws and the incidence of pedicle penetration could be significantly reduced.