Accuracy Of Pedicle Screw Placement Research Articles

Accurate placement of thoracolumbar pedicle screws using a handheld iOS-based navigation device: a prospective intra-patient agreement study

Accurate pedicle screw placement is a challenge with reported misplacement rates of 10% and higher. A handheld navigation device (HND) may provide accuracy equal to CT-based navigation (CT-Nav) but without the cost and complexity. To study the accuracy of a handheld navigation device for pedicle screw placement. This prospective cross-sectional study with consistently applied reference standard enrolled 20 patients undergoing 92 pedicle screw placements. Patients who underwent pedicle screw placement between May 2022 and September 2022. Pedicle screw placement accuracy per Gertzbein-Robbins. Once the screw pilot hole was established, the proposed trajectory of the HND was compared with that proposed by CT-Nav. Postoperatively, screw accuracy was graded according to Gertzbein-Robbins by a blinded radiologist based on CT scans. Accuracy was compared between the two systems and published control for fluoroscopy assisted and CT-Nav placement using Bayesian posterior distribution. The trajectory proposed by the HND and CT-Nav were in agreement in 98.9% (95% Exact CI; 94.09%-99.97%). The HND accuracy was 98.9% with 91 screws rated "A" and 1 rated "C". Non-inferiority to fluoroscopic placement was achieved because the one-sided normal-approximation 95% CI Lower Bound (LB) of 95.3% is greater than the Performance Goal (PG) of 83.4%. Post-hoc analysis demonstrated that the probability of superiority of the HND relative to the historical accuracy rate of 91.5% for fluoroscopy assisted procedures is >0.999 and that the HND's accuracy rate is within 4.5% of CT-Nav of 95.5% is >0.999. No adverse events or intra-operative complications associated with HND were observed. There was 1 (1.1%) intra-operative repositioning and no re-operations for any reason. The accuracy rate of the HND was 98.9%, and the proposed trajectory matched with CT-Nav in 98.9% of the time. This is superior to the historical published accuracy rate for fluoroscopy-assisted procedures and equivalent to the historical published accuracy rate for CT-Nav. Dutch trial register NL74268.058.20.

Robot-assisted pedicle screw insertion versus navigation-based and freehand techniques for posterior spinal fusion in scoliosis: a systematic review and meta-analysis.

The role of robotics in spine surgery remains controversial, especially for scoliosis correction surgery. This study aims to assess the safety and efficacy of robotic-assisted (RA) surgery specifically for scoliosis surgery by comparing RA to both navigation systems (NS) and conventional freehand techniques (CF). As per the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a systematic review and meta-analysis were conducted via an electronic search of the following databases: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL). All papers comparing RA to either NS or CF for posterior spinal fusion in scoliosis were included. Fixed and random effects models of analysis were utilised based on analysis heterogeneity. 10 observational studies were included in total. RA had significantly greater odds of accurate pedicle screw placement relative to both NS (OR = 2.02, CI = 1.52-2.67, p < 0.00001) and CF (OR = 3.06, CI = 1.79-5.23, p < 0.00001). The downside of RA was the significantly greater operation duration relative to NS (MD = 10.74, CI = 3.52-17.97, p = 0.004) and CF (MD = 40.27, CI = 20.90, p < 0.0001). Perioperative outcomes including estimated blood loss, radiation exposure, length of hospital stay, cobb angle correction rate, postoperative SRS score, VAS pain score, JOA score, as well as rates of neurological injury and revision surgery, were comparable between the groups (p > 0.05). RA offers significantly greater pedicle screw placement accuracy relative to NS and CF, however, surgery can take longer. In terms of perioperative outcomes, all three techniques are comparable.

Comparison of Cervical Pedicle Screw Placement Accuracy With Robotic Guidance System Versus Image Guidance System Using Propensity Score Matching.

A retrospective study. To compare the accuracy of cervical pedicle screw (CPS) placement using a robotic guidance system (RGS) with that of using an image guidance system (IGS; navigation system) through propensity score matching. The RGS may provide accurate CPS placement, which may outperform IGS. However, no study has directly compared the accuracy of CPS placement with the RGS to that with the IGS. We retrospectively reviewed the data of patients who had undergone cervical fusion surgery using CPS with the RGS or IGS. To adjust for potential confounders (patient demographic characteristics, disease etiology, and registration material), propensity score matching was performed, creating robotic guidance (RG) and matched image guidance (IG) groups. The accuracy of CPS placement from C2 to C6, where the vertebral artery runs, was evaluated on postoperative computed tomography images according to the Neo classification (grade 0 to grade 3). Furthermore, the intraoperative CPS revisions and related complications were examined. Using propensity score matching, 22 patients were included in the RG and matched groups each, and a total of 95 and 105 CPSs, respectively, were included in the analysis. In both the axial and sagittal planes, the clinically acceptable rate (grades 0 + 1) of CPS placement did not differ between the RG and matched IG groups (97.9% vs 94.3% and 95.8% vs 96.2%, respectively). The incidence of CPS revision was similar between the groups (2.1% vs 2.9%), and no CPS-related complications were documented. Meanwhile, the incidence of lateral breach (grades 1 + 2 + 3) was significantly lower in the RG group than in the matched IG group (1.1% vs 7.7%, P= 0.037). The RGS and IGS can equally aid in accurate and safe CPS placement in clinical settings. Nonetheless, RGS can further reduce the lateral breach, compared with IGS.

A Novel Intraoperative CT Navigation System for Spinal Fusion Surgery in Lumbar Degenerative Disease: Accuracy and Safety of Pedicle Screw Placement.

Background: In recent years, intraoperative computed tomography (CT) navigation has become widely used for the insertion of pedicle screws in spinal fusion surgery. However, conventional intraoperative CT navigation may be impaired by infrared interference between the infrared camera and surgical instruments, which can lead to the misplacement of pedicle screws. Recently, a novel intraoperative CT navigation system, NextAR, has been developed. It uses a small infrared camera mounted on surgical instruments within the surgical field. NextAR navigation can minimize the problem of infrared interference and be expected to improve the accuracy of pedicle screw placement. Methods: This study investigated the accuracy of pedicle screw insertion under NextAR navigation in spinal fusion surgery for lumbar degenerative diseases. The accuracy of pedicle screw placement was evaluated in 15 consecutive patients using a CT grading scale. Results: Screw perforation occurred in only 1 of the total 70 screws (1.4%). Specifically, there was one grade 1 perforation within 2 mm, but no perforations larger than 2 mm. There were no reoperations or neurological complications due to screw misplacement. Conclusions: NextAR navigation can provide high accuracy for pedicle screw insertion and help ensure safe spinal fusion surgery for lumbar degenerative diseases.

Efficacy of computer-assisted robotic based clinical training program for spinal oncology education on pedicle screw placement.

Pedicle screw placement (PSP) is the fundamental surgical technique that requires high accuracy for novice orthopedists studying spinal oncology education. Therefore, we set forth to establish a computer-assisted robotic navigation training program for novice spinal oncology education. Novice orthopedists were involved in this study to evaluate the feasibility and safety of the computer-assisted robotic navigation (CARN) training program. In this research, trainees were randomly taught by the CARN training program and the traditional training program. We prospectively collected the clinical data of patients with spinal tumors from 1st May 2021 to 1st March 2022. The ability of PSP was evaluated by cumulative sum (CUSUM) analysis, learning curve, and accuracy of pedicle screws. The patients included in both groups had similar baseline characteristics. In the CUSUM analysis of the learning curve for accurate PSP, the turning point in the CARN group was lower than that in the traditional group (70th vs. 92nd pedicle screw). The LC-CUSUM test indicated competency for PSP at the 121st pedicle screw in the CARN group and the 138th pedicle screw in the traditional group. The accuracy of PSP was also significantly higher in the CARN group than in the traditional group (88.17% and 79.55%, P = 0.03 < 0.05). Furthermore, no major complications occurred in either group. We first described CARN in spinal oncology education and indicated the CARN training program as a novel, efficient and safe training program for surgeons.

284 CT-Based Assessment of Prone Versus Lateral Pedicle Screw Placement Accuracy: A Retrospective Single-surgeon Study

INTRODUCTION: Lateral lumbar interbody fusion (LLIF) including the anterior-to-psoas oblique lumbar interbody fusion (OLIF) has conventionally relied on pedicle screw placement (PSP) for construct stabilization. Single-position surgery with lumbar interbody fusion (LIF) in the lateral decubitus position with concomitant PSP has been associated with increased operative efficiency. What remains unclear is the accuracy of PSP with robotic guidance when compared to the more familiar prone patient positioning. METHODS: We identified all consecutive patients treated with interbody fusion and PSP in the prone or lateral position by a single surgeon between January 2019 and October 2022. All pedicle screws placed were analyzed using CT imaging to determine appropriate positioning according to the Gertzbein-Robbins Classification Grading System. Multivariate logistic regression models were constructed to identify risk factors for the occurrence of a radiographically significant breach. RESULTS: 89 consecutive patients were included (n = 690 screws), of whom 46 were treated in the prone position (n = 477 screws) and 43 in the lateral decubitus position (n = 213 screws). There were fewer breaches in the prone (n = 13; 2.7%) versus lateral decubitus group (n = 15; 7.0%; p = 0.012). Nine (1.9%) radiographically significant breaches occurred in the prone group compared to 10 (4.7%) in the lateral decubitus group (p = 0.019), for a prone vs. lateral decubitus pedicle screw accuracy rate of 98.1% vs. 95.3%. There were no significant differences in BMI between prone vs. lateral decubitus cohorts (30.1 vs. 29.6) or breached patients vs. non-breached patients (31.2 vs. 29.5). In multivariate models, prone position was the only significant protective factor for screw accuracy; we did not identify any other significant risk factors for screw breach. CONCLUSIONS: The present data suggest pedicle screws placed with robotic assistance have higher placement accuracy in the prone position.

Analysis of guide wire displacement in robot-assisted spinal pedicle screw implantation

Robot-assisted pedicle screw placement is prone to guide wire migration, and the related influencing factors have not yet been discussed. Therefore, this study aimed to investigate and analyze the causes of robot-assisted spinal pedicle guide wire displacement and summarize the relevant treatment strategies. The surgical outcomes of 82 patients who underwent robotic-assisted pedicle screw spinal placement at our hospital between July 2022 and June 2023 were retrospectively analyzed. A total of 342 screws were placed in 82 patients; 47 guide wires were offset, 47 guide wires were replaced, and 295 guide wires were not significantly offset, with a first guide wire offset rate of 13.7% and a total guide wire offset rate of 12.1%. Univariate analysis showed that Screw placement level, whether respiration was controlled during guide wire placement, Hu value of CT, the position of needle insertion point, and operation time had a significant effect on guide wire deviation (P < 0.05). Multivariate logistic regression analysis showed that the inclusion of screw placement segments, whether breathing was controlled during guide wire placement, and Hu value of CT had a significant effect on guide wire offset (P < 0.05). Whether the guide wire was offset had no significant effect on the accuracy of subsequent pedicle screw implantation (P > 0.05). The level of screw placement, whether breathing was controlled during guide wire placement, and Hu value of CT were independent risk factors for guide wire deviation. When causing an excursion, screw orientation can be adjusted during intraoperative screw placement, and guide wire excursion has no significant impact on the accuracy of subsequent pedicle screw placement.

Clinical outcomes of 20 brachycephalic dogs with thoracolumbar spinal deformities causing neurological signs treated with spinal stabilization using 3D-printed patient-specific drill guides.

To describe the clinical outcomes for pugs and French bulldogs with congenital vertebral malformations, undergoing thoracolumbar spinal stabilization surgery using 3D-printed patient-specific drill guides. To evaluate the accuracy of pedicle screw placement in this group of dogs. Retrospective descriptive study. Twenty dogs (12 pugs and eight French bulldogs). Medical records searched between August 2018 and March 2021 for pugs and French bulldogs diagnosed with congenital vertebral abnormalities via magnetic resonance imaging (MRI) scan and computed tomography (CT) scan causing T3-L3 myelopathy signs that underwent spinal stabilization surgery using 3D-printed patient-specific drill guides followed by a postoperative CT scan. The short-term outcome was based on the neurological grade (modified Frankel score-MFS) on the day after surgery, day of discharge, and at the follow-up examination at 4 to 6 weeks after surgery. The mid-term outcome was obtained via an online questionnaire (or direct examination in one case). Twenty dogs met the inclusion criteria (19/20 grade 2 MFS, 1/20 grade 4 MFS). No complications were reported in the immediate postoperative period and optimal pedicle screw placement was obtained in 169/201 of screws. Twenty-four hours after surgery 16/20 dogs displayed an unchanged neurological grade. Short-term outcomes revealed a static (17/20) or improved (2/20) neurological grade. Ten owners participated in the online questionnaire. All patients were reported to be ambulatory; however, 7/10 dogs displayed abnormal gait. Neurological signs had remained static (6/10) or improved (3/10) in comparison with the dogs' preoperative status at a median of 883.5 days from the surgery. Dogs in this study had a favorable short-term outcome and mid-term outcome evaluation revealed a static/improved neurological status. Thoracolumbar spinal stabilization surgery using 3D-printed patient-specific drill guides showed a favorable outcome in brachycephalic breeds affected by vertebral deformities.

Comparison of the S8 navigation system and the TINAVI orthopaedic robot in the treatment of upper cervical instability.

The objective isto compare the clinical efficacy and safety of the S8 navigation system and the Tinavi orthopaedic surgery robot in the treatment of upper cervical instability. The research methods adopted are as follows. The clinical data of patients with upper cervical instability who underwent surgery from May 2021 to December 2021 were analysed retrospectively. Patients were divided into a navigation group (assisted by the S8 navigation system) and a tinavi group (assisted by the Tinavi robot) according to the auxiliary system used. Computed tomography and digital radiography were performed after the operation. The accuracy of pedicle screw placement was evaluated using the criteria put forward by Rampersaud. Degree of facet joint violation, visual analogue scale score, neck disability index and Japanese orthopaedic association score were recorded and assessed during follow-up examinations in both groups. Record two groups of surgery-related indicators. Record the complications of the two groups. A total of 50 patients were included. 21 patients in the navigation group and 29 in the tinavi group. The results of the study are as follows.The average follow-up time was 12.1months. There was no significant difference in nail placement accuracy between the navigation and tinavi groups (P > 0.05); however, the navigation group had a significantly higher rate of facet joint violation than that of tinavi group (P < 0.05), and the screws were placed closer to the anterior cortex (P < 0.05). Significantly more intraoperative fluoroscopies were performed in the tinavi group than in the navigation group, and the operation time was significantly longer in the tinavi group than in the navigation group (P < 0.05). The time of single nail implantation, intraoperative blood loss and incision length in navigation group were significantly longer than those in tinavi group. There were no statistically significant differences in other indicators between the two groups (P > 0.05). We come to the following conclusion.The Stealth Station S8 navigation system (Medtronic, USA), which also uses an optical tracking system, and the Tinavi Orthopedic robot have shown the same high accuracy and satisfactory clinical results in the treatment of upper cervical instability. Although the S8 navigation system still has many limitations, it still has good application prospects and is a new tool for spine surgery.

Comparative efficacy of robotic-assisted and freehand techniques for pedicle screw placement in spinal disorders: a meta-analysis and systematic review.

The efficacy and safety of robotic-assisted pedicle screw placement compared to traditional fluoroscopy-guided techniques are of great interest in the field of spinal surgery. This systematic review and meta-analysis aimed to compare the outcomes of these two methods in patients with spinal diseases. Following the PRISMA guidelines, we conducted a systematic search across PubMed, Embase, Web of Science, and Cochrane Library. We included randomized controlled trials comparing robotic-assisted and fluoroscopy-guided pedicle screw placement in patients with spinal diseases. Outcome measures included the accuracy of pedicle screw placement, postoperative complication rates, intraoperative radiation exposure time, and duration of surgery. Data were analyzed using Stata software. Our analysis included 12 studies. It revealed significantly higher accuracy in pedicle screw placement with robotic assistance (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 2.20-3.64, P < 0.01). Postoperative complication rates, intraoperative radiation exposure time, and duration of surgery were similar between the two techniques (OR = 0.72, 95% CI = 0.31 to 1.68, P = 0.56 for complication rates; weighted mean difference [WMD] = -0.13, 95% CI = -0.93 to 0.68, P = 0.86 for radiation exposure time; WMD = 0.30, 95% CI = -0.06 to 0.66, P = 0.06 for duration of surgery). Robotic-assisted pedicle screw placement offers superior placement accuracy compared to fluoroscopy-guided techniques. Postoperative complication rates, intraoperative radiation exposure time, and duration of surgery were comparable for both methods. Future studies should explore the potential for fewer complications with the robotic-assisted approach as suggested by the lower point estimate.

Modified Tap-drilling Technique for Mid-cervical Pedicle Screw Placement: A Case Series of 473 Consecutive Screws.

Retrospective cohort study. To report our modified tap-drilling technique for mid-cervical pedicle screw placement and to evaluate its safety and accuracy. Cervical pedicle screw fixation, which provides a strong stabilization, has been a major concern due to the potential risks to neurovascular structures despite its increasing use. Several insertion techniques have been described so far to improve the cervical pedicle screw placement accuracy. This study retrospectively reviewed patients who underwent mid-cervical (C3-C6) pedicle screw fixation between September 2005 and September 2020. Laminectomy, laminoforaminotomy, or notch-referred anatomic landmark methods were used to adjust the entry point and the direction of the screws. After the cortical bone was removed at the entry point with a diamond burr, the cancellous bone was slowly drilled with a hand drill starting from 8 to 10 millimeters in length. Then, all of the bone walls were checked with a ball-tip probe to determine if there was any breach. The procedure was repeated several times. After completing the drilling, the screw was inserted without tapping. The breach rate of pedicle screws was analyzed on postoperative computed tomography scans. A total of 473 mid-cervical pedicle screws were placed in 122 consecutive patients. No navigation or computer-assisted system was used, and the first 2 authors inserted all of the screws. All patients completed the surgery, and no evident intraoperative complications occurred. Postoperative CT scans were obtained for 405 screws. Although deviation was observed for 131 pedicle screws, a critical deviation was observed for only 25 pedicle screws. Cervical pedicle screw insertion is a risky but applicable technique. Checking all of the bone walls with a ball-tip probe before gradually advancing the hand drill in small amounts, as presented in this article, may lead to the safe and effective placement of cervical pedicle screws.

Robotic-Assisted Versus Fluoroscopic-Guided Surgery on the Accuracy of Spine Pedicle Screw Placement: A Systematic Review and Meta-Analysis.

Spinal fusion is a common method by which surgeons decrease instability and deformity of the spinal segment targeted. Pedicle screws are vital tools in fusion surgeries and advancements in technology have introduced several modalities of screw placement. Our objective was to evaluate the accuracy of pedicle screw placement in robot-assisted (RA) versus fluoroscopic-guided (FG) techniques. The PubMed and Cochrane Library databases were systematically reviewed from January 2007 through to August 8, 2022, to identify relevant studies. The accuracy of pedicle screw placement was determined using the Gertzbein-Robbins (GR) classification system. Facet joint violation (FJV), total case radiation dosage, total case radiation time, total operating room (OR) time, and total case blood loss were collected. Twenty-one articles fulfilled the inclusion criteria. Successful screw accuracy (GR Grade A or B) was found to be 1.02 (95% confidence interval: 1.01 - 1.04) times more likely with the RA technique. In defining accuracy solely based on the GR Grade A criteria, screws placed with RA were 1.10 (95% confidence interval: 1.06 - 1.15) times more likely to be accurate. There was no significant difference between the two techniques with respect to blood loss (Hedges' g: 1.16, 95% confidence interval: -0.75 to 3.06)or case radiation time (Hedges' g: -0.34, 95% CI: -1.22 to 0.53). FG techniques were associated withshorter operating room times (Hedges' g: -1.03, 95% confidence interval: -1.76 to -0.31), and higher case radiation dosage (Hedges' g: 1.61, 95% confidence interval: 1.11 to 2.10).This review suggests that RA may slightly increase pedicle screw accuracy and decrease per-case radiation dosage compared to FG techniques. However, total operating times for RA cases are greater than those for FG cases.

Assessing intraoperative pedicle screw placement accuracy using biplanar radiographs compared to three-dimensional imaging.

To date, biplanar imaging (2D) has been the method of choice for pedicle screw (PS) positioning and verified for the anteroposterior view and (spinal midline) M-line method. In recent years, the use of intraoperative three-dimensional (3D) imaging has become available with the Gertzbein-Robbins system (GRS) to assess PS breach and positioning confirmation. The aim is to determine if 2D imaging is sufficient to assess PS position in comparison to advanced 3D imaging.Retrospective review of prospectively collected data from 204 consecutive adult patients who underwent posterior thoracic and lumbar instrumented fusion for degenerative spinal surgery by a single surgeon (2019-2022).Of the 204 patients, 187 (91.6%) had intraoperative images available for analysis. A total of 1044 PS implants were used; 922 (88.3%) were robotically placed. Postoperative CT scans were verified with M-line/GRS findings. Among 103 patients (50.5%) with a total of 362 screws, (34.7%) had postoperative CT, intraoperative 3D scan, and intraoperative 2D scan for analysis. Postoperative CT findings were consistent with all GRS findings, validating that 3D imaging was accurate. Screws (1%) were falsely verified by the M-line as 3D imaging confirmed false negative or positive findings.In our series, intraoperative 3D scan was as accurate as postoperative CT scan in assessing PS breach. A significant number of PS may be falsely read as accurate on 2D imaging, that is in fact inaccurate when assessed on 3D imaging. An intraoperative post-instrumentation 3D scan may be preferable to prevent postoperative recognition of a falsely verified screw on biplanar imaging.

Pedicle screw placement accuracy in robot-assisted versus image-guided freehand surgery of thoraco-lumbar spine (ROBARTHRODESE): study protocol for a single-centre randomized controlled trial

BackgroundRobotic spinal surgery may result in better pedicle screw placement accuracy, and reduction in radiation exposure and length of stay, compared to freehand surgery. The purpose of this randomized controlled trial (RCT) is to compare screw placement accuracy of robot-assisted surgery with integrated 3D computer-assisted navigation versus freehand surgery with 2D fluoroscopy for arthrodesis of the thoraco-lumbar spine.MethodsThis is a single-centre evaluator-blinded RCT with a 1:1 allocation ratio. Participants (n = 300) will be randomized into two groups, robot-assisted (Mazor X Stealth Edition) versus freehand, after stratification based on the planned number of pedicle screws needed for surgery. The primary outcome is the proportion of pedicle screws placed with grade A accuracy (Gertzbein-Robbins classification) on postoperative computed tomography images. The secondary outcomes are intervention time, operation room occupancy time, length of stay, estimated blood loss, surgeon’s radiation exposure, screw fracture/loosening, superior-level facet joint violation, complication rate, reoperation rate on the same level or one level above, functional and clinical outcomes (Oswestry Disability Index, pain, Hospital Anxiety and Depression Scale, sensory and motor status) and cost-utility analysis.DiscussionThis RCT will provide insight into whether robot-assisted surgery with the newest generation spinal robot yields better pedicle screw placement accuracy than freehand surgery. Potential benefits of robot-assisted surgery include lower complication and revision rates, shorter length of stay, lower radiation exposure and reduction of economic cost of the overall care.Trial registrationClinicalTrials.gov NCT05553028. Registered on September 23, 2022

Clinical Observation of Posterior Approach for Surgical Treatment of Thoracolumbar Pseudarthrosis in Ankylosing Spinal Disorders

To evaluate the surgical effectiveness of posterior procedure with long segment stabilization for treating thoracolumbar pseudarthrosis associated with ankylosing spinal disorders (ASD) without anterior fusion or osteotomy. Twelve patients with thoracolumbar pseudarthrosis in ASD were enrolled. All patients underwent posterior long-segment stabilization procedures. In some patients, the percutaneous technique or the aid of a robot or O-arm navigation was utilized for pedicle screw implantation. The clinical results were evaluated by means of the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). Radiological outcomes were evaluated for bone fusion, anterior column defect, local kyphotic correction (LK) and position of the pedicle screws. All patients experienced effective bone fusion at the sites of pseudarthrosis. The mean operative time was 161.7±57.1 min, and the average amount of blood loss was 305.8 ± 293.2 ml. For six patients who underwent surgery with the assistance of a robot or O-arm navigation, there was no statistically significant difference observed in terms of operative time and mean blood loss compared to those who used the freehand technique (P>0.05). The VAS score, ODI value, and mean LK angle showed significant improvements at the final follow-up (P<0.05). The accuracy of pedicle screw placement was 96%. Posterior surgery with long-segment fixation, without anterior fusion or osteotomy, can achieve satisfactory outcomes in ASD patients with thoracolumbar pseudarthrosis. The application of percutaneous techniques, as well as the assistance of robots or navigation technique may be a good choice for the treatment of pseudarthrosis in ASD patients.

Usefulness of the spectral shaping dual-source computed tomography imaging technique in posterior corrective fusion for adolescent idiopathic scoliosis.

Since childhood exposure to radiation has been demonstrated to increase cancer risk with increase in radiation dose, reduced radiation exposure during computed tomography (CT) evaluation is desired for adolescent idiopathic scoliosis (AIS). Therefore, this retrospective study aimed to investigate the radiation dose of dual-source CT using a spectral shaping technique and the accuracy of the thoracic pedicle screw (TPS) placement for posterior spinal fusion (PSF) in patients with AIS. Fifty-nine female patients with thoracic AIS who underwent PSF using CT-guided TPSs were included and divided into two groups comprised of 23 patients who underwent dual-source CT (DSCT) with a tin filter (DSCT group) and 36 who underwent conventional multislice CT (MSCT group). We assessed the CT radiation dose using the CT dose index (CTDIvol), effective dose (ED), and accuracy of TPS insertion according to the established Neo's classification. The DSCT and MSCT groups differed significantly (p < 0.001) in the mean CTDIvol (0.76 vs. 3.31mGy, respectively) and ED (0.77 vs. 3.47mSv, respectively). Although the correction rate of the main thoracic curve in the DSCT group was lower (65.7% vs. 71.2%) (p = 0.0126), the TPS accuracy (Grades 0-1) was similar in both groups (381 screws [88.8%] vs. 600 screws [88.4%], respectively) (p = 0.8133). No patient required replacement of malpositioned screws. Spectral shaping DSCT with a tube-based tin filter allowed a 75% radiation dose reduction while achieving TPS insertion accuracy similar to procedures based on conventional CT without spectral shaping.

An Integrated 3-Dimentional Navigation System Increases the Accuracy, Efficiency, and Safety of Percutaneous Thoracolumbar Pedicle Screw Placement in Minimally Invasive Approaches: A Randomized Cadaveric Study.

Cadaveric study. The purpose of this study was to compare a novel, integrated 3D navigational system (NAV) and conventional fluoroscopy in the accuracy, efficiency, and radiation exposure of thoracolumbar percutaneous pedicle screw (PPS) placement. Twelve skeletally mature cadaveric specimens were obtained for twelve individual surgeons. Each participant placed bilateral PS at 11 segments, from T8 to S1. Prior to insertion, surgeons were randomized to the sequence of techniques and the side (left or right). Following placement, a CT scan of the spine was obtained for each cadaver, and an independent reviewer assessed the accuracy of screw placement using the Gertzbein grading system. Outcome metrics of interest included a comparison of breach incidence/severity, screw placement time, total procedure time, and radiation exposure between the techniques. Bivariate statistics were employed to compare outcomes at each level. A total of 262 screws (131 using each technique) were placed. The incidence of cortical breaches was significantly lower with NAV compared to FG (9% vs 18%; P = .048). Of breaches with NAV, 25% were graded as moderate or severe compared to 39% in the FG subgroup (P = .034). Median time for screw placement was significantly lower with NAV (2.7 vs 4.1 min/screw; P = .012), exclusive of registration time. Cumulative radiation exposure to the surgeon was significantly lower for NAV-guided placement (9.4 vs 134 μGy, P = .02). The use of NAV significantly decreased the incidence of cortical breaches, the severity of screw breeches, screw placement time, and radiation exposure to the surgeon when compared to traditional FG.

Comparison of 3D-navigation and fluoroscopic guidance in percutaneous pedicle screw placement for traumatic fractures of the thoracolumbar junction

IntroductionFractures of the thoracolumbar junction are the most common vertebral fractures and can require surgical treatment. Several studies have shown that the accuracy of pedicle screw placement can be improved by the use of 3D-navigation. Still only few studies have focused on the use of navigation in traumatic spine injuries. Research questionThe aim of this study was to compare the screw placement accuracy and radiation exposure for 3D-navigated and fluoroscopy-guided percutaneous pedicle screw placement in traumatic fractures of the thoracolumbar junction. Materials and methodsIn this single-center study 25 patients undergoing 3D-navigated percutaneous pedicle screw placement for traumatic fractures of the thoracolumbar junction (T12-L2) were compared to a control group of 25 patients using fluoroscopy. Screw accuracy was determined in postoperative CT-scans using the Gertzbein-Robbins classification system. Additionally, duration of surgery, dose area product, fluoroscopy time and intraoperative complications were compared between the groups. ResultsThe accuracy of 3D-navigated percutaneous pedicle screw placement was 92.66 % while an accuracy of 88.08 % was achieved using standard fluoroscopy (p = 0.19). The fluoroscopy time was significantly less in the navigation group compared to the control group (p = 0.0002). There were no significant differences in radiation exposure, duration of surgery or intraoperative complications between the groups. Discussion and conclusionThe results suggest that 3D-navigation facilitates higher accuracy in percutaneous pedicle screw placement of traumatic fractures of the thoracolumbar junction, although limitations should be considered. In this study 3D-navigation did not increase fluoroscopy time, while radiation exposure and surgery time were comparable.

Robotic-Assisted and Computer-Assisted Navigation Surgery in the Cervical Spine: Current Experiences, Techniques, and Accuracy

Background: In recent years, the role of robotic-assisted and computer-assisted navigation (RA-CAN) systems has significantly expanded in spine surgery, particularly those performed in the thoracic, lumbar and sacral spine showing higher accuracy in pedicle screw placement and improved surgical efficiency. However, there are few reports on these techniques in the cervical spine. The anatomy of the cervical spine possesses additional challenges such as the close proximity to critical neurovascular structures. Purpose: In this article, we present the existing clinical experience of RA-CAN in the cervical spine and evaluate technical considerations. Cervical spine screw fixation and decompression using RA-CAN are reviewed. Results: This analysis covers various aspects such as techniques, accuracy, and the types of procedures reported in the literature. Recent reports include surgical procedures such as anterior cervical diskectomy and fusion’s, odontoid fracture fixation, C1 lateral mass, C2 pedicle, translaminar, subaxial spine lateral mass, and mid-cervical spine pedicle screw fixation. There is potential for enormous clinical benefit to navigated decompression in cervical CAN procedures also. Future opportunities include further improvements in imaging co-localization, pre-surgical planning software, and mechanization of surgical procedures for instrumentation and decompression. Conclusion: The growth of RA-CAN in spinal surgery has shown significant potential in its application in the cervical spine for fusion procedures as well as decompression. By understanding the potential limitations and techniques reported from early experiences, previous techniques can be improved and provide further benefits for accuracy and less invasive surgery.

Case series: O-arm navigation assisted by the Wiltse approach improves the accuracy of pedicle screw placement in ankylosing spondylitis combined with thoracolumbar fractures

Here we assessed the accuracy of O-arm navigation assisted by Wiltse approach to improve based pedicle screw insertion in ankylosing spondylitis combined with thoracolumbar fractures. We then compared it with the freehand pedicle screw insertion technique. The study sample included 32 patients with ankylosing spondylitis combined with thoracolumbar fractures. Pedicle screw reduction and internal fixation was performed under an O-arm navigation system assisted by a Wiltse approach-combined osteotomy (“navigation group,” n = 17) and posterior pedicle screw reduction and internal fixation was performed using freehand technique combined osteotomy (“freehand group,” n = 15). We then compared the operation time and bleeding volume between the 2 groups. The visual analog scale (VAS) and Oswestry disability index (ODI) were then used to evaluate the clinical efficacy and the kyphosis Cobb angle was used to evaluate the radiological efficacy before operation, 3 days after operation and after the last follow-up. All complications were noted when detected. Finally, classification of screw positions as proposed by Neo et al was used to evaluate the relationship of the position between the screw, the bone cortex, and the incidence of screw penetration. All patients were followed up for 18 to 36 months (i.e., 24.2 ± 3.5 months). The operation time and intraoperative bleeding volume of the navigation group were significantly shorter (lower) than those of the freehand group (P &lt; .05). In addition, Both groups showed significantly decreased VAS, ODI, and Cobb angle 3 days after the operation and at the last follow-up when compared to values recorded pre-operation. However, we found no significant difference in VAS, ODI, and Cobb angle between the 2 groups (P &gt; .05). We identified no complications (e.g., infection, VTE/PE, or nerve injury). Moreover, the pedicle screw placement position of the navigation group was better than that of the freehand group (P &lt; .05), and the screw cortical penetration rate was lower than the freehand group (P &lt; .05). During the process of posterior pedicle screw placement, O-arm navigation assisted by the Wiltse approach can significantly reduce operation time, minimize the amount of bleeding volume, and enhance the accuracy of pedicle screw implantation.