Journal of Craniovertebral Junction and Spine最新文献

Background: Atlantoaxial stabilization is indicated for traumatic or degenerative pathologies. The procedure is technically demanding due to delicate neurovascular anatomy and narrow bone corridors. Recent technologies such as neuronavigation and intraoperative computed tomography (iCT) may improve screw placement and reduce complications. This study reports our experience with C1-C2 stabilization using these tools.

Materials and methods: This retrospective single-center study included 15 consecutive patients who underwent C1-C2 stabilization. Clinical assessment was performed pre- and postoperatively using the Neck Disability Index and American Spinal Injury Association score. Fractures were classified using standard parameters; degenerative cases were assessed with positional magnetic resonance imaging. Other data collected included pathology, surgical technique, sagittal/coronal alignment, complications, and follow-up duration. All surgeries used iCT for navigation and intraoperative control. Screw accuracy was assessed with a modified Gertzbein-Robbins scale.

Results: Mean patient age was 63 years. Indications were traumatic (47%) or degenerative (53%). Screws were placed into C1-C2 lateral masses. Of 60 screws, 54 were grade A and 6 were grade B. One case required recalibration due to neuronavigation inaccuracy. Alignment was restored in all cases. Thirteen patients showed significant clinical improvement. Mean follow-up was 12 months, with no complications recorded.

Conclusions: Neuronavigation with iCT for C1-C2 screw placement proved safe and accurate. Our data show 90% grade A and 10% grade B screws, with a mean deviation of 0.13 mm and no intra-or postoperative complications attributable to the technique.

Background: The Barricaid annular closure device (Intrinsic Therapeutics, Inc., Woburn, MA) functions to prevent reherniation in patients undergoing primary discectomies for L4-L5 or L5-S1 disc herniation with large annular defects. However, there are limited investigations assessing patient safety. This study analyzed clinical data on device malfunctions and adverse events to inform potential areas for improvements.

Methods: Adverse event reports related to the Barricaid device filed from January 1, 2020, to February 28, 2025, were retrieved from the U. S. Food and Drug Administration Manufacturer and User Facility Device Experience database. Event date, device type, device malfunction, and adverse event were recorded.

Results: 101 adverse event reports were included in this study. The most common malfunction was device migration (30.7%), followed by unsuccessful implantations (26.7%), which were addressed either intraoperatively (22.8%) or in revision surgeries (4.0%). Reherniation was the most frequently reported device-related adverse event (36.6%), while other postoperative complications were anticipated following spine surgeries that involved implants. Revision surgeries were performed in 67 reports following discoveries of device malfunction and/or adverse events (66.3%). 46 reoperations involved partial or complete device removal (45.5%).

Conclusion: Device malfunctions and adverse events inform the importance of careful patient selection, meticulous device handling, and improved device design in enhancing patient safety and outcomes. Patients with frailty, comorbidities, or postimplant adverse events could be subject to increased morbidity and reoperations. Continued postmarketing improvements are needed to mitigate device malfunctions and adverse events.

Context: Posterior spinal fixation surgery can improve performance status (PS), alleviate neurological deficits, and reduce pain in patients with metastatic spinal tumors. However, surgical indications and timing vary based on individual patient conditions.

Aims: To evaluate postoperative course and improvement in PS following posterior spinal fixation surgery for metastatic spinal tumors.

Settings and design: Single-center and retrospective case-series study.

Subjects and methods: We included 33 patients who underwent posterior spinal fixation surgery for metastatic spinal tumors from April 2017 to April 2024. PS and modified Frankel classification for paralysis were assessed 2 weeks' postsurgery.

Statistical analysis used: Fisher's exact test and Kaplan-Meier survival curves with a log-rank test were used for the analysis.

Results: The cohort included 33 patients (25 men, 8 women; average age, 69 years). Lung cancer was the most common primary tumor (n = 10). Surgical sites included the cervical (n = 4), thoracic (n = 14), thoracolumbar junction (n = 10), and lumbar/sacral (n = 5) regions. The median postoperative survival time was 25 months. Preoperative PS was 0-2 in 23 cases and 3-4 in 10 cases. Preoperative modified Frankel classification included A (n = 3), B (n = 2), C (n = 3), D (n = 9), and E (n = 16). Significant PS improvement was observed in the PS 0-2 group compared with that in the PS 3-4 group (P = 0.0209). Paralysis improvement was observed in 3 cases.

Conclusions: Spinal fixation can improve PS in patients with preoperative PS of 0-2. Patients with poor initial PS may not experience expected improvements, requiring cautious surgical intervention, and thorough prognostic evaluation.

Introduction: Chiari I malformation (CMI) is a complex condition characterized by cerebellar herniation through the foramen magnum and is frequently coincident with other craniovertebral junction abnormalities. Symptoms are varied, and the complete disease etiology is poorly understood. The primary aim of our study is to assess atlantal facet geometry in CMI patients to further elucidate disease pathogenesis.

Materials and methods: Forty-six CMI-affected female patients (29.48 years ± 8.35) (Chiari1000 database) and 55 female controls (32.11 years ± 4.81) (New Mexico Decedent Image Database [NMDID]) were included. Twenty 3D landmarks were placed around the perimeter of each facet by a blinded landmarker. Coordinates were subjected to a generalized Procrustes superimposition. A between-groups principal component analysis (bgPCA) was used to explore differences between groups. The protocol was completed by a second landmarker to validate results.

Results: The bgPCA scores were significantly different between CMI patients and controls (W = 689, P = 0.00022). Chiari malformation patients tended to have more negative overall scores, which coincided with smaller, more horizontally oriented facets. These differences were driven largely by the anterior aspect of the facets, which in CMI patients were notably blunted, lacking the typical medial angulation that contributes to the facet's usually reniform shape. The error study conducted by the second blinded landmarker yielded similar differences between CMI and control groups (W = 704, P = 0.00104).

Conclusions: The geometric analysis suggests distinct facet differences in CMI facet shape. CMI etiology is complex, and wholistic anatomical assessment using geometric or multiplanar methods may identify new clinical targets or provide a fresh approach to morphologically driven pathogenesis.

Introduction: While C1 screws provide an additional fixation point in occipitocervical (OC) fusion, they are often skipped due to surgical feasibility. In patients undergoing OC fusion with atlantooccipital dissociation (AOD), we sought to evaluate the impact of skipping C1 screws on: (1) construct length, (2) perioperative outcomes, and (3) long-term outcomes.

Methods: A retrospective cohort study was performed for patients with traumatic cervical injury with AOD requiring OC fusion from 2003 to 2022. The primary outcome was total levels of fusion. Perioperative outcomes included operative time, estimated blood loss, and postoperative infections. Long-term outcomes included mechanical complications and reoperation. Bivariate and multivariable linear regression controlling for age, sex, and body mass index was performed.

Results: Ninety-two patients underwent OC fusion with AOD (mean age: 40.2 ± 17.2 years) with a median follow-up of 0.9 (interquartile range: 0.4-2.8) years, and 54 (58.7%) received C1 instrumentation. Instrumenting C1 led to decreased fusion levels (2.5 ± 0.8 vs. 3.8 ± 1.0, P < 0.001) but increased operative time (192.7 ± 68.8 vs. 166.3 ± 40.5 min, P = 0.032), blood loss (369.8 ± 424.8 vs. 167.0 ± 95.8 ml, P = 0.002), and postoperative infections (11.1% vs. 0.0%, P = 0.040). There was no difference in mechanical complications (1.9% vs. 2.6%, P = 1.000) or reoperation (5.6% vs. 7.9%, P = 0.688). Mechanical complications were screw loosening (50.0%), instrumentation failure (50.0%), and pseudarthrosis (50.0%). On multivariable linear regression, C1 instrumentation was independently associated with decreased levels fused (β = --1.06, 95% confidence interval = --1.56 - -0.67, P < 0.001).

Conclusion: In OC fusion for cervical trauma, 41% of patients did not receive C1 screws. Skipping C1 was associated with longer constructs but reduced operative time, blood loss, and infection, without affecting complication or reoperation rates, highlighting the trade-offs of skipping C1 fixation.

Study design: A single-center prospective study evaluating the accuracy and factors influencing robotic-assisted pedicle screw placement in the thoracolumbar spine.

Objectives: To assess the accuracy of robotic-assisted pedicle screw placement in thoracolumbar spine surgeries and to analyze the factors that enhance or hinder the precision of robotic systems in a single-center setting.

Summary of background data: Robotic systems are significant advancement in spinal surgery, offering added advantage in pedicle screw placement compared to conventional methods such as freehand, fluoroscopy-guided, and computer-aided navigation (CAN)-guided techniques. Robots combine CAN with a stable mechanical arm, ensuring accurate placement along preplanned trajectories, particularly advantageous in complex anatomies.

Methods: A total of 410 patients who underwent robotic-assisted thoracolumbar spine surgery were included in the study. Pedicle screws were placed with robotic assistance using an optimized workflow. Screw placement accuracy was evaluated using the Gertzbein-Robbins classification, with screws graded A and B considered clinically acceptable.

Results: Of the 2600 screws placed, 99.2% were clinically acceptable (93.4% Grade A and 5.8% Grade B), with only 0.8% exhibiting breaches requiring revision. Lateral breaches were the most common (59.1%). Robotic system usage averaged 20.6 min, with an average time of 3.8 min per screw insertion. Postoperative outcomes included a mean Visual Analog Scale pain score of 7.3 and an average hospital stay of 4.7 days.

Conclusions: Robotic-assisted pedicle screw placement using the Mazor X system demonstrated high accuracy and minimal revision rates. Robotic integration reduces complications and streamlines workflows, improving patient safety and advancing spine surgery standards.

Context: Cervical laminoplasty is a motion-preserving surgical alternative to laminectomy and fusion for multilevel cervical myelopathy. While studies have explored its clinical outcomes, few have assessed national trends or projected future procedural volumes, particularly within the aging Medicare population.

Aims: The aim of this study is to analyze historical trends in cervical laminoplasty utilization within the Medicare population and project future procedural volumes through 2060.

Settings and design: Retrospective trend analysis using a national database.

Subjects and methods: A retrospective analysis was conducted using the Centers for Medicare and Medicaid Services Medicare Part B National Summary database from 2005 to 2022. Laminoplasty procedures were identified using current procedural terminology codes 63050 and 63051. To account for increasing Medicare Advantage enrollment, a correction factor was applied based on Kaiser Family Foundation data.

Statistical analysis used: Four forecasting models - log-linear, Poisson, negative binomial regression, and auto-regressive integrated moving average - were evaluated to project future utilization. Model performance was assessed using mean absolute error and root mean square error. The Poisson regression model was selected for its balance of predictive accuracy and reliability.

Results: From 2005 to 2022, laminoplasty volume increased 200.7%, from 811 to 2,437 procedures annually. The Poisson model projected an average 5.1% annual growth rate, with procedural volume reaching 15,528 by 2060 (95% confidence interval: 13,992-17,234), representing a 537% increase from 2022 levels.

Conclusions: Cervical laminoplasty utilization is projected to increase considerably through 2060. As demand rises, further studies should explore factors influencing growth and assess broader implications for surgical decision-making and policy.

Background: Cervical pedicle screws provide superior biomechanical fixation with pullout strength four times greater than lateral mass screws, but placement is technically demanding with traditional malposition rates of 6.7%-31.6%. Robotic-assisted spine surgery has demonstrated success in thoracolumbar applications, but cervical translation has been hindered by the lack of cervical-specific instrumentation requiring expensive custom instruments.

Methods: We developed a hybrid technique combining robotic guidance with standard cervical instrumentation using minimally invasive surgery dilators as an interface. Sixty-five consecutive patients underwent robot-assisted cervical pedicle screw placement with 565 screws across C2-C7 levels using MazorX Stealth robotic system with O-arm navigation. Accuracy was assessed using Gertzbein-Robbins and Neo classification systems with 3-6-month follow-up for complications.

Results: The technique achieved 98.76% clinically acceptable accuracy (Gertzbein-Robbins Grade A + B) with 1.24% breach rate. Perfect placement (Grade A) occurred in 95.22% of screws. Vertebral artery protection was excellent with 99.65% showing no foramen breach. Major complications occurred in 1.5% of patients (single vertebral artery injury), with 7.7% experiencing transient C5 weakness that resolved completely. No patients required revision surgery.

Conclusions: This hybrid technique addresses instrument compatibility barriers in robotic cervical spine surgery by eliminating dependence on custom instruments while maintaining robotic accuracy. The technique demonstrates superior outcomes compared to traditional approaches and facilitates broader robotic cervical surgery adoption. Multi-center validation studies are needed to establish the generalizability.

Objective: The objective of this study was to explore the normal matching changes between T1 slope (T1S) and cervical lordosis (CL) in patients with multilevel cervical spondylotic myelopathy (CSM) after anterior and posterior reconstruction surgeries.

Materials and methods: One hundred thirty-four patients diagnosed with multilevel CSM and a normal matching of T1S-CL were enrolled from the medical records spanning 2015-2020. The anterior group comprised 69 patients, and the posterior group included 65 patients. This study retrospectively analyzed perioperative parameters, including clinical parameters of the Japanese Orthopedic Association (JOA) score, Visual Analog Scale (VAS), neck disability index (NDI), and radiologic parameters T1S, CL, C2-7 sagittal vertical axis (SVA), and T1S-CL.

Results: Prior to surgery, there were no significant differences in factors between two groups (P > 0.05). Postoperatively, while the JOA scores were similar between groups (P > 0.05), the anterior group showed significantly lower in NDI, VAS, perioperative parameters, and incidences of complications (P < 0.001). Significant changes were observed in each group for T1S, CL, C2-7 SVA and T1S-CL (P < 0.001). Preoperatively, in the anterior group, significant correlations were identified between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). In the posterior group, significant correlations were observed between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). Following surgery, in the anterior group, the correlations persisted between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). In the posterior group, the correlations between T1S-CL and T1S, and CL were not significant (P > 0.05). The comparative analysis of parameter changes between anterior and posterior groups revealed no significant difference in the changes of T1S and C2-7 SVA (P > 0.05), whereas significant differences were observed in the changes of C2-7 lordosis and T1S-CL (P < 0.001).

Conclusions: Anterior reconstruction surgeries can improve or optimize the normal matching of T1S-CL, while a mismatching of T1S and CL is more likely to occur after posterior surgery, potentially leading to cervical sagittal malalignment and imbalance in patients with multilevel CSM.

Background: L5-S1 is a challenging level for achieving fusion, where traditional transforaminal lumbar interbody fusion (TLIF) techniques may fail to maintain disc height and lordosis. Expandable cages, offering in situ expansion, may improve radiographic outcomes. Their use specifically at L5-S1 has not been previously studied.

Methods: We retrospectively reviewed patients ≥18 years who underwent TLIF at L5-S1 between January 2015 and September 2023. Patients were grouped by cage type (expandable vs. static). Radiographic data included anterior and posterior disc heights, disc angle, L5-S1, L4-S1, and L1-S1 sagittal lordotic angles, and lumbar distribution index. Measurements were recorded preoperatively and at two postoperative intervals.

Results: A total of 43 patients were analyzed (15 expandable, 28 static). At baseline, the expandable group had greater posterior disc height (5.03 mm vs. 3.06 mm, P < 0.001). At first follow-up, expandable cages showed higher anterior disc height (18.86 mm vs. 11.80 mm, P < 0.001), posterior disc height (7.80 mm vs. 5.30 mm, P < 0.001), and disc angle (16.27° vs. 11.82°, P = 0.040). From preoperative to final follow-up, expandable cages had greater gains in anterior disc height (9.22 mm vs. 3.27 mm, P < 0.001), disc angle (7.84° vs. 0.24°, P = 0.002), and L5-S1 lordosis (7.03° vs. 0.81°, P = 0.012).

Conclusions: Expandable TLIF cages at L5-S1 offer significantly improved radiographic correction over static cages, addressing key limitations of traditional posterior approaches.