Pack Years of Tobacco Cigarette Smoking as a Predictor of Bony Fusion After Anterior Cervical Discectomy and Fusion.

OBJECTIVE: Smoking tobacco cigarettes negatively impacts bone healing after spinal fusion. Smoking history is often assessed based on current smoker and nonsmoker status. However, in current research, smoking history has not been quantified in terms of pack years to estimate lifetime exposure and assess its effects. Our goal was to investigate the influence of smoking history, quantified in pack years, on bony fusion after anterior cervical discectomy and fusion (ACDF). METHODS: A retrospective chart review of consecutive patients who underwent ACDF for cervical disc degeneration between September 21, 2017 and October 17, 2018 was conducted. Patient demographics, procedural variables, and postoperative outcomes were analyzed. Multivariate logistic regression analysis was performed to identify predictive factors for bony fusion following ACDF. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal discrimination threshold for smoking history pack years in association with nonfusion. RESULTS: Among 97 patients identified, 90 (93%) demonstrated bony fusion on postoperative imaging. Mean number of smoking history pack years was 6.1±13 for the fusion group and 16 ±21 for the nonfusion group. Multivariate logistic regression analysis suggested that increased pack years of tobacco cigarette smoking was a significant predictor of nonfusion (95% confidence interval, [1.0,1.1], p=0.045). The ROC curve analysis revealed that 6.1 pack years best stratified the risk for nonfusion (area under the curve, 0.8). CONCLUSION: Patients with a history of tobacco cigarette smoking >6.1 pack years may have an increased risk of nonfusion after ACDF.

Supraclavicular Artery Island Flap for Treatment of Cervical Wound Defects and Persistent Cerebrospinal Fluid Leaks: A Technical Note and Systematic Review of the Literature.

BACKGROUND: Soft tissue defects and persistent cerebrospinal fluid (CSF) leaks can create complications after cervical spinal surgery. The supraclavicular artery island (SAI) flap is useful in closing tissue defects, particularly in these complex surgeries and multiple reinterventions. However, technical reports in this context are scarce. We describe application of the SAI flap technique to control persistent CSF leak in the first documented instance (to our knowledge) of a low-grade fibromyxoid sarcoma (LGFMS) in the cervical epidural space. Additionally, we conducted a comprehensive review of PubMed, Embase, and Google Scholar from their earliest records through December 17, 2023 using combined terms, "supraclavicular artery island flap AND spine" and "supraclavicular AND flap AND spine". TECHNICAL NOTE: A 56-year-old woman with arm pain and weakness presented with a cervical epidural mass extending from C4-C6 and associated spinal cord compression. She underwent a 3-level corpectomy and tumor resection. Primary dural closure was impossible due to the dural invasion, and reintervention with an SAI flap and definitive lumboperitoneal shunting were required to control and seal the CSF leak. SYSTEMATIC LITERATURE REVIEW: Seven case reports describing SAI flap for spinal surgery complications were identified. The indications in those cases were correcting esophageal and hypopharyngeal perforations after cervical fusion and discectomy and persistent soft tissue coverage after cervical instrumentation. CONCLUSIONS: The SAI flap technique provided wound defect coverage in this case and is suitable for addressing issues such as persistent CSF leaks or soft tissue coverage after cervical spine surgery.

The Effect of Diabetes on Complications after Spinal Fusion: A Systematic Review and Meta-Analysis.

OBJECTIVE: Spinal fusion procedures are used to treat a wide variety of spinal pathologies. Diabetes mellitus (DM) has been shown to be a significant risk factor for several complications following these procedures in previous studies. To the authors' knowledge, this is the first systematic review and meta-analysis elucidating the relationship between DM and complications occurring after spinal fusion procedures. METHODS: Systematic literature searches of PubMed and EMBASE were performed from their inception to October 1, 2022, to identify studies that directly compared postfusion complications in patients with and without DM. Studies met the prespecified inclusion criteria if they reported the following data for patients with and without DM: (1) demographics; (2) postspinal fusion complication rates; and (3) postoperative clinical outcomes. The included studies were then pooled and analyzed. RESULTS: Twenty-eight studies, with a cumulative total of 18,853 patients (2695 diabetic patients), were identified that met the inclusion criteria. Analysis showed that diabetic patients had significantly higher rates of total number of postoperative complications (odds ratio [OR] = 1.33; 95% confidence interval [CI] = 1.12-1.58; P = 0.001), postoperative pulmonary complications (OR=2.01; 95%CI=1.31-3.08; P = 0.001), postoperative renal complications (OR=2.20; 95%CI=1.27-3.80; P = 0.005), surgical site infection (OR=2.65; 95%CI=2.19-3.20; P < 0.001), and prolonged hospital stay (OR=1.67; 95%CI=1.47-1.90; P < 0.001). CONCLUSIONS: Patients with DM had a significantly higher risk of developing complications after spinal fusion, particularly pulmonary and renal complications, in addition to surgical site infections and had a longer length of stay. These findings are important for informed discussions of surgical risks with patients and families before surgery.

Clinical and Radiographic Outcomes of Anterior Lumbar Interbody Fusions (ALIFs) Using a Titanium Cage with a Biomimetic Surface.

OBJECTIVE We analyzed clinical and radiographic outcomes in patients undergoing anterior lumbar interbody fusions (ALIFs) using a new biomimetic titanium fusion cage (Titan nanoLOCK interbody, Medtronic, Minneapolis, Minnesota). This specialized cage employs precise nanotechnology to stimulate inherent biochemical and cellular osteogenic reactions to the implant, aiming to amplify the rate of fusion. To our knowledge, this is the only study to assess early clinical and radiographic results in ALIFs. METHODS We conducted a retrospective review of data for patients who underwent single or multilevel ALIF using this implant between October 2016 and April 2021. Indications for treatment were spondylolisthesis, post-laminectomy syndrome, or spinal deformity. Clinical and radiographic outcome data for these patients were collected and assessed. RESULTS A total of 84 patients were included. The mean clinical follow-up was 36.6±14 months. At 6 months, solid fusion was seen in 97.6% of patients. At 12 months, solid fusion was seen in 98.8% of patients. Significant improvements were seen in patient-reported outcome measures (PROMs) (visual analog scale and Oswestry Disability Index) at 6 and 12 months compared to the preoperative scores (P<0.001). One patient required reoperation for broken pedicle screws 2 days after the ALIF. None of the patients required readmission within 90 days of surgery. No patients experienced an infection. CONCLUSIONS ALIF using a new titanium interbody fusion implant with a biomimetic surface technology demonstrated high fusion rates (97.6%) as early as 6 months. There was significant improvement in PROMs at 6 and 12 months.

Advancing Prone-Transpsoas Spine Surgery: A Narrative Review and Evolution of Indications with Representative Cases.

The Prone Transpsoas (PTP) approach to lumbar spine surgery, emerging as an evolution of lateral lumbar interbody fusion (LLIF), offers significant advantages over traditional methods. PTP has demonstrated increased lumbar lordosis gains compared to LLIF, owing to the natural increase in lordosis afforded by prone positioning. Additionally, the prone position offers anatomical advantages, with shifts in the psoas muscle and lumbar plexus, reducing the likelihood of postoperative femoral plexopathy and moving critical peritoneal contents away from the approach. Furthermore, operative efficiency is a notable benefit of PTP. By eliminating the need for intraoperative position changes, PTP reduces surgical time, which in turn decreases the risk of complications and operative costs. Finally, its versatility extends to various lumbar pathologies, including degeneration, adjacent segment disease, and deformities. The growing body of evidence indicates that PTP is at least as safe as traditional approaches, with a potentially better complication profile. In this narrative review, we review the historical evolution of lateral interbody fusion, culminating in the prone transpsoas approach. We also describe several adjuncts of PTP, including robotics and radiation-reduction methods. Finally, we illustrate the versatility of PTP and its uses, ranging from 'simple' degenerative cases to complex deformity surgeries.

Vertebral Bone Quality Score as a Predictor of Adjacent Segment Disease After Lumbar Interbody Fusion.

BACKGROUND AND OBJECTIVE: With lumbar spine fusion being one of the most commonly performed spinal surgeries, investigating common complications such as adjacent segment disease (ASD) is a high priority. To the authors' knowledge, there are no previous studies investigating the utility of the preoperative magnetic resonance imaging-based vertebral bone quality (VBQ) score in predicting radiographic and surgical ASD after lumbar spine fusion. We aimed to investigate the predictive factors for radiographic and surgical ASD, focusing on the predictive potential of the VBQ score. METHODS: A single-center retrospective analysis was conducted of all patients who underwent 1-3 level lumbar or lumbosacral interbody fusion for lumbar spine degenerative disease between 2014 and 2021 with a minimum 12 months of clinical and radiographic follow-up. Demographic data were collected, along with patient medical, and surgical data. Preoperative MRI was assessed in the included patients using the VBQ scoring system to identify whether radiographic ASD or surgical ASD could be predicted. RESULTS: A total of 417 patients were identified (mean age, 59.8 ± 12.4 years; women, 54.0%). Eighty-two (19.7%) patients developed radiographic ASD, and 58 (13.9%) developed surgical ASD. A higher VBQ score was a significant predictor of radiographic ASD in univariate analysis (2.4 ± 0.5 vs 3.3 ± 0.4; P < .001) and multivariate analysis (odds ratio, 1.601; 95% CI, 1.453-1.763; P < .001). For surgical ASD, a significantly higher VBQ score was seen in univariate analysis (2.3 ± 0.5 vs 3.3 ± 0.4; P < .001) and served as an independent risk factor in multivariate analysis (odds ratio, 1.509; 95% CI, 1.324-1.720; P < .001). We also identified preoperative disk bulge and preoperative existence of adjacent segment disk degeneration to be significant predictors of both radiographic and surgical ASD. Furthermore, 3-level fusion was also a significant predictor for surgical ASD. CONCLUSION: The VBQ scoring system might be a useful adjunct for predicting radiographic and surgical ASD.

Cervical Vertebral Bone Quality Score Independently Predicts Distal Junctional Kyphosis After Posterior Cervical Fusion.

BACKGROUND AND OBJECTIVE: Posterior cervical fusion is the surgery of choice when fusing long segments of the cervical spine. However, because of the limited presence of this pathology, there is a paucity of data in the literature about the postoperative complications of distal junctional kyphosis (DJK). We aimed to identify and report potential associations between the preoperative cervical vertebral bone quality (C-VBQ) score and the occurrence of DJK after posterior cervical fusion. METHODS: The authors retrospectively reviewed records of patients who underwent posterior cervical fusion at a single hospital between June 1, 2010, and May 31, 2020. Patient data were screened to include patients who were >18 years old, had baseline MRI, had baseline standing cervical X-ray, had immediate postoperative standing cervical X-ray, and had clinical and radiographic follow-ups of >1 year, including a standing cervical X-ray at least 1 year postoperatively. Univariate analysis was completed between DJK and non-DJK groups, with multivariate regression completed for relevant clinical variables. Simple linear regression was completed to analyze correlation between the C-VBQ score and total degrees of kyphosis angle change. RESULTS: Ninety-three patients were identified, of whom 19 (20.4%) had DJK and 74 (79.6%) did not. The DJK group had a significantly higher C-VBQ score than the non-DJK group (2.97 ± 0.40 vs 2.26 ± 0.46; P < .001). A significant, positive correlation was found between the C-VBQ score and the total degrees of kyphosis angle change (r 2 = 0.26; P < .001). On multivariate analysis, the C-VBQ score independently predicted DJK (odds ratio, 1.46; 95% CI, 1.27-1.67; P < .001). CONCLUSION: We found that the C-VBQ score was an independent predictive factor of DJK after posterior cervical fusion.

Comparative Analysis of the 3 Cervical Vertebral Bone Quality (C-VBQ) Score Methodologies and Their Correlations to the Lumbar Vertebral Bone Quality (VBQ) Score.

OBJECTIVE: Common complications after spinal fusion, such as pseudoarthrosis, cage subsidence, or instrumentation failure, are affected by patients' bone quality. The cervical-vertebral bone quality (C-VBQ) score, a magnetic resonance imaging (MRI)-based adaption of the lumbar vertebral bone quality (VBQ) score, was developed by 3 separate research groups simultaneously to evaluate bone quality in cervical spinal fusion patients. We present the first analysis comparing these scoring methods to the well-validated VBQ score. METHODS: A retrospective analysis of data for consecutive patients who underwent spine surgery at a single institution was completed. The VBQ score was calculated using the Ehresman et al. METHOD: The C-VBQ scores, named according to placement of the region of interest within the cerebral spinal fluid, were calculated separately using the methods of Soliman et al. (C2-VBQ), Razzouk et al. (C5-VBQ), and Huang et al. (T1-VBQ). Linear regression models were utilized to evaluate correlations to the VBQ score. RESULTS: A total of 105 patients were identified (mean age, 57.0 ± 11.9 years; women, 50.5%). Mean scores were C2-VBQ, 2.37 ± 0.55; C5-VBQ, 2.36 ± 0.61; and T1-VBQ, 2.64 ± 0.68. The C-VBQ scores for the C2 level were significantly higher than those for the C3-C6 levels (3.18 ± 0.96 vs. 2.63 ± 0.77, P < 0.001), whereas the C7 level was found to have significantly lower C-VBQ scores (2.42 ± 0.78 vs. 2.63 ± 0.77, P = 0.04). The C2-VBQ (r = 0.63) score had the strongest correlation to the VBQ score, compared to C5-VBQ (r = 0.41) and T1-VBQ (r = 0.43) (P < 0.001). CONCLUSIONS: This study demonstrates that the C2-VBQ had the strongest correlation to the lumbar VBQ score among all C-VBQ scores.

Tension Parameters of Junctional Tethers in Proximal Junction Kyphosis: A Cadaveric Biomechanical Study.

OBJECTIVE: Proximal junctional failure following surgical correction for adult spinal deformity significantly impacts quality of life and increases the economic burden of treating underlying spinal deformity. The objective of this cadaver study was to determine optimal tension parameters in junctional tethers for proximal junctional kyphosis prevention. METHODS: Cadaveric specimens were used to establish the optimal tension range in polyethylene tethering devices, such as the VersaTie (NuVasive) used in this study. Three specimens were instrumented to test tether tensions of 0, 75, and 150 Newtons (N) at L1-L2, T9-T10, and T3-T4. An optical tracking system was used to measure when specimens reached proximal junctional kyphosis, experienced instrumentation or tissue failure, or reached a cap of 2500 cycles. Radiographs were obtained before and after testing. RESULTS: At all levels, use of a tether at tension forces of 75 N and 150 N elicited a protective effect. The only level in which a higher tension on the tether resulted in more protection was at T3-T4. When averaged, the use of a tether at tension forces of 75 N and 150 N showed 1000 cycles of protection at L1-L2, 2000 cycles at T9-T10, and 1426 cycles at T3-T4. Radiographic analysis corroborated these findings. CONCLUSIONS: The use of a tether in a cadaveric model prevents the development of proximal junctional kyphosis across all tested levels and an increased tension force of 150 N is protective at the proximal thoracic spine. These data can be used to develop further models for a tether system that reproducibly applies a fixed tension force above the thoracolumbar rod construct.

Standalone versus Anterior Cervical Plating for One-To-Two Level Anterior Cervical Discectomy and Fusion: A Propensity Score-Matched Comparative Study.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) can be performed with and without supportive anterior cervical plating. Fusion rates, incidence of dysphagia, and repeat surgery are concerns when performing ACDF with or without plating. We aimed to compare procedural success and outcomes between patients treated with and without cervical plating for 1-2 level ACDF. METHODS: A prospectively maintained database was retrospectively searched for patients who underwent 1-2 level ACDF surgery. Patients were divided into cohorts treated with plating and without (standalone). Propensity score matching (PSM) was performed to eliminate selection bias and control for baseline comorbidities and disease severity. Patient demographics (including age, body mass index, smoking status, diabetes mellitus, osteoporosis), disease presentation (cervical stenosis, degenerative disc disease), and operative details (number of operative levels, cage type used, intraoperative, and postoperative complications) were recorded. Outcomes assessed were fusion observed at 3, 6, and 12 months, patient-reported postoperative pain, and any repeat surgeries. Univariate analysis was performed according to data normality and variables for PSM cohorts. RESULTS: A total of 365 patients were identified (plating=289, standalone=76). After PSM, 130 patients (65 in each group) were included for final analysis. Similar mean operative times (101.3 ± 26.5-standalone; 104.8 ± 32.2-plating; P = 0.5) and mean hospital stays (1.2 ± 1.8-standalone; 0.7 ± 0.7-plating; P = 0.1) were noted. Twelve-month fusion rates were also similar (84.6%-standalone; 89.2%-plating; P = 0.6). Repeat surgery rates were equivalent (13.8%-standalone; 12.3%-plating; P = 0.8). CONCLUSIONS: In this propensity score-matched case-control study, we report comparable effectiveness and outcomes of performing 1-2 level ACDF with and without cervical plating.

Pedicle Screw Placement Accuracy in Robot-Assisted Spinal Fusion in a Multicenter Study.

Pedicle screw fixation is a spinal fusion technique that involves the implantation of screws into vertebral pedicles to restrict movement between those vertebrae. The objective of this research is to measure pedicle screw placement accuracy using a novel automated measurement system that directly compares the implanted screw location to the planned target in all three anatomical views. Preoperative CT scans were used to plan the screw trajectories in 122 patients across four surgical centers. Postoperative scans were fused to the preoperative plan to quantify placement accuracy using an automated measurement algorithm. The mean medial-lateral and superior-inferior deviations in the pedicle region for 500 screws were 1.75 ± 1.36 mm and 1.52 ± 1.26 mm, respectively. These deviations were measured using an automated system and were statistically different from manually determined values. The uncertainty associated with the fusion of preoperative to postoperative images was also quantified to better understand the screw-to-plan accuracy results. This study uses a novel automated measurement system to quantify screw placement accuracy as it relates directly to the planned target location, instead of analyzing for breaches of the pedicle, to quantify the validity of using of a robotic-guidance system for accurate pedicle screw placement.

Complications of the Prone Transpsoas Lateral Lumbar Interbody Fusion for Degenerative Lumbar Spine Disease: A Multicenter Study.

BACKGROUND AND OBJECTIVES: The prone transpsoas (PTP) approach for lateral lumbar interbody fusion (LLIF) is a novel technique for degenerative lumbar spine disease. However, there is a paucity of information in the literature on the complications of this procedure, with all published data consisting of small samples. We aimed to report the intraoperative and postoperative complications of PTP in the largest study to date. METHODS: A retrospective electronic medical record review was conducted at 11 centers to identify consecutive patients who underwent LLIF through the PTP approach between January 1, 2021, and December 31, 2021. The following data were collected: intraoperative characteristics (operative time, estimated blood loss [EBL], intraoperative complications [anterior longitudinal ligament (ALL) rupture, cage subsidence, vascular and visceral injuries]), postoperative complications, and hospital stay. RESULTS: A total of 365 patients were included in the study. Among these patients, 2.2% had ALL rupture, 0.3% had cage subsidence, 0.3% had a vascular injury, 0.3% had a ureteric injury, and no other visceral injuries were reported. Mean operative time was 226.2 ± 147.9 minutes. Mean EBL was 138.4 ± 215.6 mL. Mean hospital stay was 2.7 ± 2.2 days. Postoperative complications included new sensory symptoms-8.2%, new lower extremity weakness-5.8%, wound infection-1.4%, cage subsidence-0.8%, psoas hematoma-0.5%, small bowel obstruction and ischemia-0.3%, and 90-day readmission-1.9%. CONCLUSION: In this multicenter case series, the PTP approach was well tolerated and associated with a satisfactory safety profile.

Outcomes of 2-Level Versus 3- or 4-Level Anterior Cervical Discectomy and Fusion Using a Biomimetic Surface Titanium Cage: Multicenter Experience.

OBJECTIVE: Interbody cages for spinal fusions are primarily constructed from polyetheretherketone or titanium compositions. However, these crude macroscopic materials pose limitations for improving the rates of bony fusions. The authors aimed to compare the fusion rates and postoperative complications in patients who underwent 2-level or 3-or 4-level anterior cervical discectomy and fusion (ACDF) performed with the use of a novel biomimetic surface titanium cage. METHODS: A retrospective multicenter study was conducted that included all patients who underwent multilevel ACDF with this cage between January 2017 and April 2021. Patient demographics and procedure-related, radiographic, and postoperative complication data were collected. RESULTS: A total of 124 patients were identified; 69 (55.6%) had a 3-or 4-level fusion and 55 (44.4%) had a 2-level fusion. The demographics of the 2 groups differed significantly only in terms of age (P = 0.01). At 3 months, a significantly higher solid fusion rate was found for 2-level fusions than 3-or 4-level fusions (83.7% vs. 56.3%, P = 0.004); however, significance was lost at 6-months (98.2% vs. 88.4%, respectively; P = 0.08). No patients required posterior supplemental fixation. Transient dysphagia was the only postoperative complication that was significantly increased in the 3-or 4-level fusion group compared to the 2-level group (27.5% vs. 9.1%, P = 0.02). CONCLUSIONS: Radiographic and clinical outcomes were equivalent in 3-or 4-level and 2-level ACDFs in which these biomimetic surface titanium cages were used. Furthermore, the use of this technology led to high fusion rates with no requirement for posterior supplemental fusions.

Strong Correlation Between the Vertebral Bone Quality Score and the Cervical-Vertebral Bone Quality Score in Spine Surgery Patients.

OBJECTIVE: Osteoporosis is a burgeoning public health problem for over 44 million people in the United States. The magnetic resonance imaging-based vertebral bone quality (VBQ) score and cervical VBQ (C-VBQ) score are two novel approaches that use data routinely gathered during preoperative evaluation to assess bone quality. The goal of this study was to investigate the relationship between the VBQ and C-VBQ scores. METHODS: We performed a retrospective review of chart data for patients who underwent spine surgery for degenerative conditions between 2015 and 2022. Patients eligible for study inclusion had preoperative T1-weighted magnetic resonance imaging of the lumbar and cervical spine available for review. Demographics of each patient were collected. The VBQ score was determined by dividing the median signal intensity (SI) of the L1-L4 vertebral bodies by the SI of the cerebrospinal fluid at L3. The C-VBQ score was calculated by dividing the median SI of the C3-C6 vertebral bodies by the SI of the C2 cerebrospinal fluid space. Pearson's correlation test was utilized to evaluate the association between the scores. RESULTS: We identified 171 patients, with a mean age of 57.44 ± 11.79 years. The interrater reliability of the VBQ and C-VBQ measurements was excellent (intraclass correlation-coefficients were 0.89 and 0.84, respectively). A statistically significant, positive correlation was found between the VBQ score and the C-VBQ score (r = 0.757,P < 0.001). CONCLUSIONS: This is the first study, to our knowledge, to assess the degree to which the newly developed C-VBQ score correlates with the VBQ score. We found a strong positive correlation between the scores.

Predictive Factors of Intraoperative and Early Postoperative Outcome Measures After Anterior Lumbar Interbody Fusions Based on American Society of Anesthesiologists Score.

OBJECTIVE: Anterior lumbar interbody fusion (ALIF) is a surgical treatment that requires a close operative plane to the great vessels, which increases the risk of perioperative complications. To our knowledge, no previous study has investigated the American Society of Anesthesiologists (ASA) Physical Status Classification System as a predictive factor for unfavorable perioperative outcomes in ALIF procedures. We aimed to analyze the ASA score as a predictive factor of intraoperative and postoperative outcomes in patients undergoing ALIFs. METHODS: A retrospective chart review was completed at each center to identify a consecutive set of patients who underwent an ALIF. Univariate and multivariate analyses between patients with preoperative ASA scores of ≤2 and >2 were performed to identify predictive factors that may contribute to adverse intraoperative and early postoperative outcomes. RESULTS: Among 210 patients identified, 59 (28.1%) had an ASA score >2 and 151 (71.9%) had an ASA score ≤2. On multivariate analysis, an ASA score >2 was predictive of increased 90-day reoperations (P = 0.02), estimated blood loss (EBL) (P = 0.02), and operative time (P = 0.02). Previous lumbar surgery was predictive of increased length of stay (P = 0.005), EBL (P < 0.001), 90-day readmission (P = 0.02), and operative time (P < 0.001). Posterior supplemental fixation was predictive of increased length of stay (P = 0.04). Increased number of operative levels was predictive of increased EBL (P < 0.001) and operative time (P < 0.001). Perioperative anticoagulation use was predictive of increased EBL (P < 0.001) CONCLUSIONS: Increased ASA scores were associated with unfavorable outcomes after ALIF and also can be used as a predictive tool for the risk of reoperations.

A Novel Cervical Vertebral Bone Quality Score Independently Predicts Cage Subsidence After Anterior Cervical Diskectomy and Fusion.

BACKGROUND: Surgeons can preoperatively assess bone quality using dual-energy X-ray absorptiometry or computed tomography; however, this is not feasible for all patients. Recently, a MRI-based scoring system was used to evaluate the lumbar spine's vertebral bone quality. OBJECTIVE: To create a similar MRI-based scoring system for the cervical spine (C-VBQ), correlate C-VBQ scores with computed tomography-Hounsfield units (HU), and evaluate the utility of this scoring system to independently predict cage subsidence after single-level anterior cervical diskectomy and fusion (ACDF). METHODS: Demographic, procedure-related, and radiographic data were collected for patients. Pearson correlation test was used to determine the correlation between C-VBQ and HU. Cage subsidence was defined as ≥3 mm loss of fusion segmental height. A multivariate logistic regression model was built to determine the correlation between potential risk factors for subsidence. RESULTS: Of 59 patients who underwent single-level ACDF, subsidence was found in 17 (28.8%). Mean C-VBQ scores were 2.22 ± 0.36 for no subsidence levels and 2.83 ± 0.38 ( P < .001) for subsidence levels. On multivariate analysis, a higher C-VBQ score was significantly associated with subsidence (odds ratio = 1.85, 95% CI = 1.39-2.46, P < .001) and was the only significant independent predictor of subsidence after ACDF. There was a significant negative correlation between HU and C-VBQ (r 2 = -0.49, P < .001). CONCLUSION: We found that a higher C-VBQ score was significantly associated with cage subsidence after ACDF. Furthermore, there was a significant negative correlation between C-VBQ and HU. The C-VBQ score may be a valuable tool for assessing preoperative bone quality and independently predicting cage subsidence after ACDF.

Complications associated with subaxial placement of pedicle screws versus lateral mass screws in the cervical spine (C2-T1): systematic review and meta-analysis comprising 4,165 patients and 16,669 screws.

Lateral mass screw (LMS) and cervical pedicle screw (CPS) fixation are among the most popular techniques for posterior fusion of the cervical spine. Early research prioritized the LMS approach as the trajectory resulted in fewer neurovascular complications; however, with the incorporation of navigation assistance, the CPS approach should be re-evaluated. Our objective was to report the findings of a meta-analysis focused on comparing the LMS and CPS techniques in terms of rate of various complications with inclusion of all levels from C2 to T1. We conducted a systematic review of PubMed and EMBASE databases with final inclusion criteria focused on identifying studies that reported outcomes and complications for either the CPS or LMS technique. These studies were then pooled, and statistical analyses were performed from the cumulative data. A total of 60 studies comprising 4165 participants and 16,669 screws placed within the C2-T1 levels were identified. Within these studies, the LMS group had a significantly increased odds for lateral mass fractures (odds ratio [OR] = 43.2, 95% confidence interval [CI] = 2.62-711.42), additional cervical surgeries (OR = 5.56, 95%CI = 2.95-10.48), and surgical site infections (SSI) (OR = 5.47, 95%CI = 1.65-18.16). No other significant differences between groups in terms of complications were identified. Within the subgroup analysis of navigation versus non-navigation-guided CPS placement, no significant differences were identified for individual complications, although collectively significantly fewer complications occurred with navigation (OR = 5.29, 95%CI = 2.03-13.78). The CPS group had significantly fewer lateral mass fractures, cervical revision surgeries, and SSIs. Furthermore, navigation-assisted CPS placement was associated with a significant reduction in complications overall.

Radiographic alignment outcomes after the single-position prone transpsoas approach: a multi-institutional retrospective review of 363 cases.

OBJECTIVE: The aim of this paper was to evaluate the changes in radiographic spinopelvic parameters in a large cohort of patients undergoing the prone transpsoas approach to the lumbar spine. METHODS: A multicenter retrospective observational cohort study was performed for all patients who underwent lateral lumber interbody fusion via the single-position prone transpsoas (PTP) approach. Spinopelvic parameters from preoperative and first upright postoperative radiographs were collected, including lumbar lordosis (LL), pelvic incidence (PI), and pelvic tilt (PT). Functional indices (visual analog scale score), and patient-reported outcomes (Oswestry Disability Index) were also recorded from pre- and postoperative appointments. RESULTS: Of the 363 patients who successfully underwent the procedure, LL after fusion was 50.0° compared with 45.6° preoperatively (p < 0.001). The pelvic incidence-lumbar lordosis mismatch (PI-LL) was 10.5° preoperatively versus 2.9° postoperatively (p < 0.001). PT did not significantly change (0.2° ± 10.7°, p > 0.05). CONCLUSIONS: The PTP approach allows significant gain in lordotic augmentation, which was associated with good functional results at follow-up.