Journal of Craniovertebral Junction and Spine最新文献

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.

Objective: The odontoid process is an important anatomical structure providing a balance of mobility and stability at the craniocervical junction, with structural and biomechanical associations, and morphology that can be quantified with various measurements. The odontoid tilt angle is a measurement that must be accurately performed and can guide further investigations.

Materials and methods: Retrospective analysis of 100 cervical spinal magnetic resonance imaging was performed on patients investigated for neck pain, with a known history of scoliosis, and compared with 50 control patients. Posterior odontoid tilt and Cobb angles were measured by a musculoskeletal radiology fellow and a fellowship-trained musculoskeletal radiologist with more than 10 years of experience, with descriptive statistics then performed on the measurements.

Results: One hundred and thirty-two patients met the inclusion criteria, across both the scoliosis and control groups. 9 (18%) patients from the control group demonstrated posterior odontoid tilt, compared with 35 (43%) of patients in the scoliosis group. A range of scoliosis curve morphologies were demonstrated: 62 thoracolumbar, 10 thoracic, 9 lumbar, and 1 cervicothoracic, with average Cobb angles of 24.3°, 26.9°, 23.4, and 54°, respectively. There was good interobserver agreement for both measurements and a statistically significant difference in the posterior odontoid tilt measurements between groups (99% confidence interval, P = 0.0064).

Conclusion: We recommend opportunistically assessing for the posterior odontoid tilt (Leaning odontoid tower of BRUMES (Botchu; Raja Rasul; Uldin; Morgan;Elias; Sonal, Shashank, Shirodkar). In cases with a posterior tilt angle >5°, we recommend whole spine imaging to assess for scoliosis in the thoracolumbar spine.

A styloid process >3 cm is known as Eagle's syndrome (ES). This syndrome can lead to neurovascular symptoms. Traumatic atlantoaxial rotatory subluxation (AARS) is very rare in adults. We diagnosed AARS in a patient with ES after high-energy trauma. Posterior C1-2 stabilization was performed under traction. We wanted to discuss the mechanism of AARS in ES based on this case.

Introduction: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is commonly used to treat lumbar spine pathologies such as degenerative disc disease and spondylolisthesis. Despite its advantages, standard MIS-TLIF has limitations, including restricted visualization, radiation exposure, and technical challenges. Navigation-assisted modified MIS-TLIF has been developed to enhance precision and safety. This study compares the clinical and radiological outcomes of navigation-assisted modified MIS-TLIF versus standard MIS-TLIF.

Materials and methods: This retrospective study included 66 patients who underwent lumbar fusion surgery between April 2020 and March 2023. Patients were divided into two groups: 30 underwent navigation-assisted modified MIS-TLIF and 36 underwent standard MIS-TLIF. Inclusion criteria included chronic low back pain due to lumbar degenerative conditions unresponsive to conservative management and single level pathology. Parameters evaluated included operative time, blood loss, hospital stay, complication rate, screw placement accuracy, fusion status (Bridwell grading), and functional outcomes assessed using the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS).

Results: The navigation-assisted group demonstrated lower blood loss, shorter hospital stays, and fewer complications. Pedicle screw placement accuracy was higher (96.7% vs. 88.9%). Fusion rates were comparable (Grade 1 fusion: 93.3% vs. 88.9%). Both groups showed significant improvement in ODI and VAS scores over 1 year. Final ODI and VAS scores were slightly better in the standard MIS-TLIF group but not statistically significant.

Conclusion: Navigation-assisted modified MIS-TLIF offers improved accuracy, reduced complications, and enhanced perioperative outcomes as compared to standard MIS-TLIF, while achieving similar long-term clinical and radiological results.

Background: Facet joint degeneration represents a common source of low back pain and contributes to the development of lumbar spinal stenosis (LSS). We sought to identify the prevalence of facet syndrome in patients with LSS planned to undergo decompression and placement of facet cages (FFX^® device, SC Medica) and the relationship of medial branch block (MBB) test results with postoperative visual analog scale (VAS) pain scores.

Materials and methods: LSS patients undergoing decompression and placement of facet cages performed for a period of 1 year were included. Patients who did not undergo an MBB test prior to surgery were excluded.

Results: A total of 22 patients met the inclusion criteria for the study. The mean age was 69.4 ± 12.9 years with a majority of patients (63.6%) being female. Sixteen of the 22 (73%) patients had a positive MBB test. VAS scores were similar at baseline between the MBB positive and negative subgroups. The improvement in postoperative VAS back scores compared to baseline was greater for patients with a positive block test compared to those with a negative test (-4.7 vs. -1.8, respectively). As expected with the decompression part of the procedure, the improvement of VAS leg scores was similar for patients with positive and negative block tests compared to baseline.

Conclusion: The present study documents the high prevalence of facet syndrome in patients with LSS and the clinical benefits associated with the use of facet fusion cages to reduce facet-generated back pain.