Search Results (9)

Background: Fractures of the upper cervical spine are challenging to treat due to their proximity to critical neurovascular structures and the need for immediate, stable fixation. Open posterior fixation remains the standard but is associated with soft-tissue disruption and morbidity. Minimally invasive, navigation-assisted pedicle screw fixation represents a viable alternative for older populations, significantly reducing surgical morbidity and tissue trauma. The present study evaluates the accuracy, safety, and perioperative outcomes of minimally invasive navigated posterolateral C1–C2 fixation. Methods: We conducted a retrospective consecutive case review of 51 patients who underwent minimally invasive C1–C2 screw fixation between 2019 and 2024. All procedures were performed using intraoperative O-arm imaging and StealthStation S8 navigation. Screw placement accuracy was assessed using the Bredow modification of the Gertzbein–Robbins and Heary classifications. Perioperative data, including operative time, screw dimensions, radiation dose, complications, and hospital stay, were recorded. Results: Fifty-one patients were included in the study. A total of 212 screws were placed. According to Gertzbein–Robbins grading, 92.4% were Grade A, 6.6% were Grade B, and 1% were Grade C. According to Heary grading, 95% were Grade I and 5% were Grade III. No vertebral artery injuries, new neurological deficits, or intraoperative hardware failures occurred. The mean screw lengths were 33.2 mm (SD = 3.38 mm) (C1) and 32 mm (SD = 4.30 mm) (C2). The mean operative time was 128 min (SD = 52.95 min). The mean radiation dose was 629.16 mGy·cm² (SD = 372.2 mGy·cm²). One superficial wound infection occurred. The median postoperative NRS was 4 (IQR: 4–5). The mean hospital stay was 4.21 (SD = 3.77) days. Conclusions: Our findings demonstrate that the presented approach for C1–C2 fixation is a highly accurate and safe alternative to open posterior fixation for upper cervical fractures. Full article

Objectives: The Goel–Harms technique provides rapid stabilization and high fusion rates for atlantoaxial instability but carries a risk of neurovascular injury during lateral mass and pedicle screw insertion. Recently, 3D printing has emerged as a cost-effective and increasingly accessible tool in various surgical fields. This study aimed to compare the clinical and radiological outcomes of C1–C2 fixation using a 3D-printed template versus the free-hand technique. Methods: This retrospective cohort study included patients who underwent C1–C2 fixation with the Goel–Harms technique at two tertiary neurosurgical centers between 2021 and 2023. Operative, radiological, and functional outcomes were reviewed in 21 patients who were operated using either a patient-specific 3D-printed template applied intraoperatively (Group 1; n = 10) or the free-hand technique (Group 2; n = 11). Postoperative screw accuracy was assessed using the Gertzbein–Robbins classification. Results: A total of 84 screws were placed (Group 1: 40; Group 2: 44). In Group 1, 38 of 40 screws (95%) were accurately placed, compared with 41 of 44 screws (93.1%) in Group 2. The mean fluoroscopy and operative times were significantly shorter in Group 1 than in Group 2 (21.90 ± 4.33 s vs. 27.09 ± 13.48 s, p = 0.012; 126.60 ± 28.70 min vs. 171.36 ± 40.44 min, p = 0.010, respectively). Conclusions: The 3D-printed template technique significantly reduced operative and fluoroscopy times compared with the free-hand technique. Three-dimensional printing offers a cost-effective alternative to conventional navigation systems by eliminating their time-consuming preoperative setup in the operating room. Full article

Background/Objectives: Pedicle screw placement is crucial for restoring stability. Emerging robot-assisted technologies may offer enhanced precision and reduced radiation exposure. This study aimed to compare the accuracy and clinical outcomes of robot-assisted versus conventional fluoroscopy-guided pedicle screw placements. Methods: This retrospective cohort study included 218 patients undergoing pedicle screw placement at a single spine center between 2019 and 2023. Of these, 105 patients underwent robot-assisted surgery using the Mazor X™ Stealth Edition (Medtronic, Minneapolis, MN, USA), and 113 underwent conventional fluoroscopy-guided surgery. The primary outcome was screw placement accuracy (Grade 0 = optimal, Grades 1–3 = suboptimal, according to the Gertzbein–Robbins classification). Secondary outcomes included estimated blood loss (EBL), radiation exposure, length of hospital stay (LOS), clinical outcome according to the Macnab classification, postoperative pain, and adverse events. Results: Robot-assisted surgery demonstrated significantly higher accuracy in screw placement, with 93.33% achieving Grade 0 accuracy versus 78.76% in the conventional group (p = 0.002). This corresponded to an odds ratio (OR) of 3.78 (95% CI: 1.55–9.19, p = 0.003). The number needed to treat (NNT) to achieve one additional optimal screw placement was 6.9. Robot-assisted surgery demonstrated significantly higher accuracy in screw placement. Moreover, robot-assisted procedures were associated with reduced estimated blood loss (EBL), shorter length of stay (LOS), and lower radiation exposure times; patient-reported outcomes (VAS and Macnab) were also improved (OR = 3.34, 95% CI: 1.89–5.91). Duration of surgery, adverse events, and revision rates were comparable between the two groups. Conclusions: This study supports the clinical benefits of robot-assisted pedicle screw placement, particularly in achieving higher accuracy and reducing EBL and LOS. Future research should explore long-term outcomes, cost-effectiveness, and the generalizability of these results to a broader patient population. Full article

Background/Objectives: While biomechanically superior, cervical pedicle screw placement is technically challenging, and therefore typically performed only in centers with the aid of navigation. The purpose of this study was to analyze the accuracy and safety of navigated cervical pedicle screw (CPS) placement using intraoperative imaging with a workflow using a navigated high-speed drill in a large single-center cohort. Methods: We conducted a retrospective analysis of 205 patients undergoing posterior cervical or cervicothoracic instrumentation between January 2018 and June 2024. Accuracy was assessed using the Gertzbein–Robbins classification, with grades 0 and 1 considered satisfactory. Surgical workflow, intraoperative imaging, and complications were analyzed. Results: A total of 1112 pedicle screws, including 888 cervical and 224 upper thoracic screws, were evaluated. 801 were grade 0 (72.0%), 250 grade 1 (22.5%), 56 grade 2 (5.0%), and 5 grade 3 (0.4%). Cervical screws achieved satisfactory placement grades 0 and 1 in 93.1%, and upper thoracic screws in 100% (92.0% grade 0, 8.0% grade 1). Grade 3 breaches occurred in C2, C3, C5, C6, and C7, with one case each. There were no cases of implant-related neurovascular injuries. Conclusions: This study demonstrates high screw accuracy with a low observed complication rate. No revision surgeries were required due to screw malposition, but 7 cases of screw loosening occurred. However, the retrospective design and reliance on intraoperative imaging limit the generalizability of the findings. Full article

Achieving precise pedicle screw placement in posterior lumbar interbody fusion (PLIF) is essential but difficult due to the intricacies of manual preoperative planning with CT scans. We analyzed CT data from 316 PLIF patients, using Mimics software for manual planning by two surgeons. A deep learning model was trained on 228 patients and validated on 88 patients, assessing planning efficiency and accuracy. Automatic planning successfully segmented and placed screws in all 316 cases, significantly outperforming manual planning in speed. The Dice coefficient for segmentation accuracy was 0.95. The difference in mean pedicle transverse angle (PTA) and pedicle sagittal angle (PSA) for automatic planning screws compared to manual planning screws was 1.63 ± 0.83° and 1.39 ± 1.03°, respectively, and these differences were either statistically comparable or not significantly different compared to the variability of manual planning screws. The average Dice coefficient of implanted screws was 0.63 ± 0.08, and the consistency between automatic screws and manual reference screws was higher than that of internal screws (Dice 0.62 ± 0.09). Compared with manual screws, automatic screws were shorter (46.58 ± 3.09 mm) and thinner (6.24 ± 0.35 mm), and the difference was statistically significant. In qualitative validation, 97.7% of the automatic planning screws were rated Gertzbein–Robbins (GR) Class A and 97.3% of the automatic planning screws were rated Badu Class 0. Deep learning software automates lumbosacral pedicle screw planning, enhancing surgical efficiency and accuracy. Full article

(1) Background: Our team has previously introduced the Single-Step Pedicle Screw System (SSPSS), which eliminates the need for K-wires, as a safe and effective method for percutaneous minimally invasive spine (MIS) pedicle screw placement. Despite this, there are ongoing concerns about the reliability and accuracy of screw placement in MIS procedures without traditional tools like K-wires and Jamshidi needles. To address these concerns, we evaluated the accuracy of the SSPSS workflow by comparing the planned intraoperative screw trajectories with the final screw positions. Traditionally, screw placement accuracy has been assessed by grading the final screw position using postoperative CT scans. (2) Methods: We conducted a retrospective review of patients who underwent lumbar interbody fusion, using intraoperative 3D navigation for screw placement. The planned screw trajectories were saved in the navigation system during each procedure, and postoperative CT scans were used to evaluate the implanted screws. Accuracy was assessed by comparing the Gertzbein and Robbins classification scores of the planned trajectories and the final screw positions. Accuracy was defined as a final screw position matching the classification of the planned trajectory. (3) Results: Out of 206 screws, 196 (95%) were accurately placed, with no recorded complications. (4) Conclusions: The SSPSS workflow, even without K-wires and other traditional instruments, facilitates accurate and reliable pedicle screw placement. Full article

Background: Transforaminal lumbar interbody fusion (TLIF) is one of the most frequently performed spinal fusion techniques, and this minimally invasive (MIS) approach has advantages over the traditional open approach. A drawback is the higher radiation exposure for the surgeon when conventional fluoroscopy (2D-fluoroscopy) is used. While computer-assisted navigation (CAN) reduce the surgeon’s radiation exposure, the patient’s exposure is higher. When we investigated 2D-fluoroscopically guided and 3D-navigated MIS TLIF in a randomized controlled trial, we detected low radiation doses for both the surgeon and the patient in the 2D-fluoroscopy group. Therefore, we extended the dataset, and herein, we report the radiation-sparing surgical technique of 2D-fluoroscopy-guided MIS TLIF. Methods: Monosegmental and bisegmental MIS TLIF was performed on 24 patients in adherence to advanced radiation protection principles and a radiation-sparing surgical protocol. Dedicated dosemeters recorded patient and surgeon radiation exposure. For safety assessment, pedicle screw accuracy was graded according to the Gertzbein–Robbins classification. Results: In total, 99 of 102 (97.1%) pedicle screws were correctly positioned (Gertzbein grade A/B). No breach caused neurological symptoms or necessitated revision surgery. The effective radiation dose to the surgeon was 41 ± 12 µSv per segment. Fluoroscopy time was 64 ± 34 s and 75 ± 43 radiographic images per segment were performed. Patient radiation doses at the neck, chest, and umbilical area were 65 ± 40, 123 ± 116, and 823 ± 862 µSv per segment, respectively. Conclusions: Using a dedicated radiation-sparing free-hand technique, 2D-fluoroscopy-guided MIS TLIF is successfully achievable with low radiation exposure to both the surgeon and the patient. With this technique, the maximum annual radiation exposure to the surgeon will not be exceeded, even with workday use. Full article

The insertion of pedicle screws in the lateral position without a position change has been reported. We completed a retrospective comparison of the radiologic and clinical outcomes of 36 patients who underwent either single-position oblique lateral lumbar interbody fusion (SP-OLIF) using the O-arm (36 cases) or conventional OLIF (C-OLIF) using the C-arm (20 cases) for L2–5 single-level lumbar degenerative diseases. Radiological parameters were analyzed, including screw accuracy (Gertzbein-Robbins classification system; GRS), segmental instability, and fusion status. Screw misplacement was defined as a discrepancy of ≥2 mm. Clinical outcomes, including visual analog scale, Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36), and postoperative complications, were assessed. The spinal fusion rate was not different between the SP-OLIF and C-OLIF groups one year after surgery (p = 0.536). The ODI score was lower (p = 0.015) in the SP-OLIF than the C-OLIF group. Physical (p = 0.000) and mental component summaries (p = 0.000) of the SF-36 were significantly higher in the SP-OLIF group. Overall complication rates, including revision, surgical site infection, ipsilateral weakness, and radicular pain/numbness, were not significantly different. SP-OLIF using the O-arm procedure is feasible, with acceptable accuracy, fusion rate, and complication rate. This may be an alternative to conventional two-stage operations. Full article

Background and Objectives: In the literature, spinal navigation and robot-assisted surgery improved screw placement accuracy, but the majority of studies only qualitatively report on screw positioning within the vertebra. We sought to evaluate screw placement accuracy in relation to a preoperative trajectory plan by three-dimensional quantification to elucidate technical benefits of navigation for lumbar pedicle screws. Materials and Methods: In 27 CT-navigated instrumentations for degenerative disease, a dedicated intraoperative 3D-trajectory plan was created for all screws. Final screw positions were defined on postoperative CT. Trajectory plans and final screw positions were co-registered and quantitatively compared computing minimal absolute differences (MAD) of screw head and tip points (mm) and screw axis (degree) in 3D-space, respectively. Differences were evaluated with consideration of the navigation target registration error. Clinical acceptability of screws was evaluated using the Gertzbein–Robbins (GR) classification. Results: Data included 140 screws covering levels L1-S1. While screw placement was clinically acceptable in all cases (GR grade A and B in 112 (80%) and 28 (20%) cases, respectively), implanted screws showed considerable deviation compared to the trajectory plan: Mean axis deviation was 6.3° ± 3.6°, screw head and tip points showed mean MAD of 5.2 ± 2.4 mm and 5.5 ± 2.7 mm, respectively. Deviations significantly exceeded the mean navigation registration error of 0.87 ± 0.22 mm (p < 0.001). Conclusions: Screw placement was clinically acceptable in all screws after navigated placement but nevertheless, considerable deviation in implanted screws was noted compared to the initial trajectory plan. Our data provides a 3D-quantitative benchmark for screw accuracy achievable by CT-navigation in routine spine surgery and suggests a framework for objective comparison of screw outcome after navigated or robot-assisted procedures. Factors contributing to screw deviations should be considered to assure optimal surgical results when applying navigation for spinal instrumentation. Full article