Anterior Cervical Discectomy And Fusion Research Articles

Is single-level cervical disc arthroplasty associated with a lower reoperation rate than anterior cervical discectomy and fusion?

Long-term meta-analysis of cervical disc arthroplasty (CDA) trials report lower rates of subsequent cervical spine surgical procedures with CDA compared with anterior cervical discectomy and fusion (ACDF). The objective of this study was to compare the rate of subsequent cervical spine surgery in single-level CDA-treated patients to that of a matched cohort of single-level ACDF-treated patients by using records from 2010 to 2021 included in a large national administrative claims database (PearlDiver). This retrospective matched-cohort study used a large national insurance claims database; 525,510 patients who had undergone a single-level ACDF or CDA between 2010 and 2021 were identified. Patients with other same-day spine procedures, as well as those for trauma, infection, or tumor, were excluded, yielding 148,531 patients. ACDF patients were matched 2:1 to CDA patients on the basis of clinical and demographic characteristics. The primary outcome was the overall incidence of all-cause cervical reoperation after index surgery. Secondary outcomes included readmission, any adverse event within 90 days, and overall reintervention after index surgery. Multivariable logistic regression analyses were adjusted for covariates and were employed to estimate the effect of the index ACDF or CDA procedure on patient outcomes. Survival was assessed using Kaplan-Meier estimation, and differences between ACDF- and CDA-treated patients were compared using log-rank tests. After the patients were matched, 28,795 ACDF patients to 14,504 CDA patients were included. ACDF patients had higher rates of 90-day adverse events (18.4% vs 14.6%, adjusted odds ratio [aOR] 0.77, 95% CI 0.73-0.82, p < 0.001) and readmission (11.5% vs 9.7%, aOR 0.87, 95% CI 0.81-0.93, p < 0.001). Over a mean 4.3 years of follow-up, 5.0% of ACDF patients and 5.4% of CDA patients underwent reoperation (aOR 1.09, 95% CI 1.00-1.19, p = 0.059). The rate of aggregate reintervention was higher in CDA patients than in ACDF patients (11.7% vs 10.7%, aOR 1.10, p = 0.002). The Kaplan-Meier 10-year reoperation-free survival rate was worse for CDA than ACDF (91.0% vs 92.0%, p = 0.05), as was the rate of reintervention-free survival (81.2% vs 82.0%, p = 0.003). Single-level CDA was associated with a similar rate of reoperation and higher rate of subsequent injections when compared with a matched cohort that underwent single-level ACDF. CDA was associated with lower rates of 90-day adverse events and readmissions.

A comparative and prospective study of surgical outcomes of cervical artificial disc to anterior cervical discectomy and fusion in the treatment of symptomatic degenerative disc disease of cervical spine in a tertiary care center of Eastern India

Background: Cervical disc degeneration is known to be a primary cause of neck pain and neurologic symptoms and can cause significant morbidity. Degeneration can be related to radiculopathy or myelopathy due to compression of spinal nerves and/or spinal cord. Disc pathology may manifest clinically as localized and radicular pain, myelopathy, and spinal joint instability. If severe, such as in degenerative disc disease, infections, and trauma, surgical methods are indicated. Some studies reported that compared to anterior cervical discectomy and fusion (ACDF), cervical artificial disc (CAD) could provide better neurological outcomes and reduce the rate of adjacent segment degeneration, whereas other studies reported no difference between the two procedures. Aims and Objectives: The aim of this study was to compare surgical outcomes of CAD to anterior cervical discectomy and fusion in the treatment of symptomatic degenerative disc disease in cervical spine. Materials and Methods: It was a comparative study with prospective design conducted among 40 symptomatic cervical disc degenerative disease patients (20 patients undergoing CAD and the remaining 20 anterior cervical discectomy and fusion) at the Department of Neurosurgery, Bangur Institute of Neurosciences, 1PGMER and SSKM Hospital, Kolkata, from January 2021 to December 2022. Respective surgical procedures were done. All patients were required to return for follow-up. Clinical and radiological evaluations were performed at 1 month, 3 months, 1 year, postoperatively, and last follow-up (more than 18 months). Clinical effectiveness was evaluated by the visual analog scale (VAS) score, Japanese Orthopedic Association (JOA) score (17 points system, 1994 revised edition), and neck disability index (NDI) score. Results: Improvement in NDI, VAS, and JOA index was found to be more in CAD as compared to ACDF group with a statistically significant difference as P&lt;0.05. Subsequent surgical intervention was reported among four subjects, out of which one belonged to the CAD group while the rest three to ACDF. Overall success was found to be more in the CAD group (75%) as compared to the ACDF group (55%), though no significant difference was revealed as P&gt;0.05. Conclusion: The findings of the present study support the superior longevity and better outcome of CDA, as compared with ACDF, with regard to need for subsequent surgical intervention and also support better improvement in symptoms in subsequent follow-up in patients undergoing CDA as compared to ACDF despite having comparable mean operative time and blood loss.

A New Method to Evaluate Pressure Distribution Using a 3D-Printed C2-C3 Cervical Spine Model with an Embedded Sensor Array

Cervical degenerative disc diseases such as myelopathy and radiculopathy often require conventional treatments like artificial cervical disc replacement or anterior cervical discectomy and fusion (ACDF). When designing a medical device, like the stand-alone cage, there are many design inputs to consider. However, the precise biomechanics of the force between the vertebrae and implanted devices under certain conditions require further investigation. In this study, a new method was developed to evaluate the pressure between the vertebrae and implanted devices by embedding a sensor array into a 3D-printed C2-C3 cervical spine. The 3D-printed cervical spine model was subjected to a range of axial loads while under flexion, extension, bending and compression conditions. Cables were used for the application of a preload and a robotic arm was used to recreate the natural spine motions (flexion, extension, and bending). To verify and predict the total pressure between the vertebrae and the implanted devices, a 3D finite element (FE) numerical mathematical model was developed. A preload was represented by applying 22 N of force on each of the anterior tubercles for the C2 vertebra. The results of this study suggest that the sensor is useful in identifying static pressure. The pressure with the robot arm was verified from the FE results under all conditions. This study indicates that the sensor array has promising potential to reduce the trial and error with implants for various surgical procedures, including multi-level artificial cervical disk replacement and ACDF, which may help clinicians to reduce pain, suffering, and costly follow-up procedures.

Efficacy of Allograft Versus Bioactive Glass-Ceramic Cage in Anterior Cervical Discectomy and Fusion: A Randomized Controlled Study.

A randomized controlled trial. The aim of this study is to compare the efficacy of allografts and bioactive glass-ceramic (BG) cages for anterior cervical discectomy and fusion (ACDF) in treating cervical degenerative disc disease. We conducted a single-center, randomized controlled trial between August 2017 and August 2022. Participants were randomized into two groups, and consecutive patients requiring ACDF were randomly assigned to receive either the allograft cage or the BG cage. The surgical outcomes measured included pain levels, neck disability, surgical details, and radiological assessments. Of the 45 assessed, 40 participants were included, with 18 in the allograft cage group and 22 in the BG cage group. By the 12-month follow-up, both groups exhibited significant improvements in pain levels and disability scores, with no notable intergroup differences. Over 85% of patients in both groups were satisfied with their outcomes. Radiological assessments revealed stability in the cervical spine with both cage types post intervention. Although both materials showed a trend toward increased subsidence over time, the difference between them was not statistically significant. Fusion rates were comparable between the groups at 12 months, with BG cage showing a slightly higher early fusion rate at 6 months. No significant differences were observed between the two groups in terms of complications. Both allograft and BG cages are effective in ACDF surgeries for cervical degenerative disc disease, with both contributing to substantial postoperative improvements. Differences in disc height, interspinous motion, and subsidence were not significant in the last follow-up, indicating both materials' suitability for clinical use. Future research with a larger cohort and longer follow-up is needed to confirm these preliminary findings.

Assessment of organ doses, peak skin doses and effective doses in patients undergoing anterior cervical discectomy and fusion utilising VirtualDose-IR software.

In this study, the effect of patient- and procedure-related parameters on organ doses (ODs), peak skin dose (PSD) and effective dose (E) during anterior cervical discectomy and fusion (ACDF) was evaluated. Patient- and procedure-related parameters, as well as fluoroscopy time, kerma-area product (KAP), cumulative air-kerma (Kair) and incident Kair, were analysed for 50 ACDF procedures performed with a mobile C-arm. These parameters were inserted in VirtualDose-IR software implementing sex-specific and body mass index (BMI)-adjustable anthropomorphic phantoms to calculate OD, PSD and E. The BMI, gender and type of implants did not significantly affect KAP, incident Kair, PSD and E. However, the type of fusion significantly affected the E. The single fusions in C5/C6 resulted in significantly higher KAP, incident Kair and E than C4/C5 levels, while those performed in C6/C7 resulted in significantly higher E and PSD than C4/C5 levels. The thyroid, oesophagus and salivary glands received the largest doses in all groups studied. The BMI did not significantly affect ODs. The salivary glands absorbed significantly higher doses in males than females, while the extrathoracic region's dose significantly increased for multi- than single-level fusions. The fusions in C6/C7 resulted in significantly higher oesophagus and thyroid doses than C3/C4 and C4/C5 levels, as well as fusions performed in C5/C6 compared with C4/C5 levels. The data presented here could be used by the neurosurgeons as a comparator for future studies in optimising radiation protection during ACDF procedures in the operating theatre by keeping the ODs, PSD and E as low as reasonably practicable.

Optimizing Patient Outcomes in Spinal Surgery: An Investigation Into Anesthesiologists' Case Volume.

Introduction Nearly one million patients in the United States undergo spine surgical procedures annually to seek relief from chronic back and neck pain. A multidisciplinary approach is key to ensuring the efficiency and safety of the surgical process, with the anesthesia team, nursing, surgeon, and healthcare facilities all playing a role. The purpose of this study is to capture potential associations between the anesthesiologists' case volume and patient postoperative outcomes in the early recovery period. Methods A retrospective review of anterior cervical discectomy and fusion (ACDF), lumbar decompression (LD), and lumbar fusion (LF) patients from July 2019 to June 2023 was performed. Anesthesiologists were categorized into low, medium, and high volumes of spine surgical cases. Univariate analysis was performed on patient demographics, intraoperative measures, post-anesthesia care unit (PACU) measures, and postoperative measures by anesthesiologist volume. Results This study included 545 ACDF, 815 LD, and 1,144 LF patients. There were no differences between groups in ACDF patients by anesthesiologist volume. When examining patients undergoing LD, there was a difference in patients with an American Society of Anesthesiologists (ASA) physical status classification of three or greater (low volume: 41.7% vs. medium volume: 53.7% vs. high volume: 45.0%; p=0.029). When examining patients undergoing LF, there were differences in patients with low temperatures in PACU (low volume: 2.8% vs. medium volume: 7.3% vs. high volume: 4.2%; p=0.044) and the percentage of patients with a 90-day emergency department return (low volume: 7.7% vs. medium volume: 11.9% vs. high volume: 7.0%; p=0.024). Conclusion While this study found a minimal impact of anesthesiologist volume on postoperative outcomes, recent literature has emphasized the critical role of teamwork and specialized surgical teams to enhance efficiency and patient care. Further studies are warranted to identify other variables in anesthesia, nursing, and surgical team workflow that may impact postoperative outcomes in spinal surgeries.

Monomelic Amyotrophy/Hirayama Disease: Surgical Outcome in a Large Cohort of Indian Patients

Hirayama disease (HD) is a cervical compressive myelopathy. Anterior cervical discectomy and fusion (ACDF) is identified as the best surgical approach. We evaluated surgical outcomes and factors influencing ACDF in HD. Between 2015 and 2019, 126 patients with HD underwent ACDF. Contrast magnetic resonance imaging of the cervical spine in full flexion was performed. Clinical examination and preoperative/postoperative assessment of hand function using Fugl-Meyer assessment, Jebsen-Taylor hand function test, and handheld dynamometry were performed at 3-monthly intervals for 1 year. Surgical outcomes were assessed as per the Odom criteria and Hirayama outcome questionnaire. Age at onset and duration of illness were 12-31 years (mean, 18 ± 2.7) and 1-96 months (32.7 ± 24.4), respectively. All patients had progressive weakness and wasting of the affected limb. Cord atrophy was seen in 97.1%, with epidural detachment and engorgement of the posterior epidural venous plexus in all. All patients underwent ACDF. Of these patients, 54% had an excellent/good outcome and 39% had a satisfactory outcome as per the Odom scale at last follow-up (mean, 44.9 ± 16.5 months) after surgery. Handheld dynamometry showed improvement from preoperative values to 1 year follow-up. Duration of illness and age at onset had a negative correlation and the preoperative Fugl-Meyer score had a positive correlation with improvement. ACDF resulted in remarkable improvement or stabilization in neurologic deficits in many patients with HD. Because motor disability ensues over time, early surgical intervention during the progressive phase is advocated.

Predicting conversion of ambulatory ACDF patients to inpatient: a machine learning approach

Background ContextMachine learning is a powerful tool that has become increasingly important in the orthopedic field. Recently, several studies have reported that predictive models could provide new insights into patient risk factors and outcomes. Anterior cervical discectomy and fusion (ACDF) is a common operation that is performed as an outpatient procedure. However, some patients are required to convert to inpatient status and prolonged hospitalization due to their condition. Appropriate patient selection and identification of risk factors for conversion could provide benefits to patients and the use of medical resources. PurposeThis study aimed to develop a machine-learning algorithm to identify risk factors associated with unplanned conversion from outpatient to inpatient status for ACDF patients. Study Design/SettingThis is a machine-learning-based analysis using retrospectively collected data. Patient SamplePatients who underwent one- or two-level ACDF in an ambulatory setting at a single specialized orthopedic hospital between February 2016 to December 2021. Outcome MeasuresLength of stay, conversion rates from ambulatory setting to inpatient. MethodsPatients were divided into two groups based on length of stay: (1) Ambulatory (discharge within 24 hours) or Extended Stay (greater than 24 hours but fewer than 48 hours), and (2) Inpatient (greater than 48 hours). Factors included in the model were based on literature review and clinical expertise. Patient demographics, comorbidities, and intraoperative factors, such as surgery duration and time, were included. We compared the performance of different machine learning algorithms: Logistic Regression, Random Forest (RF), Support Vector Machine (SVM), and Extreme Gradient Boosting (XGBoost). We split the patient data into a training and validation dataset using a 70/30 split. The different models were trained in the training dataset using cross-validation. The performance was then tested in the unseen validation set. This step is important to detect overfitting. The performance was evaluated using the area under the curve (AUC) of the receiver operating characteristics analysis (ROC) as the primary outcome. An AUC of 0.7 was considered fair, 0.8 good, and 0.9 excellent, according to established cut-offs. ResultsA total of 581 patients (59% female) were available for analysis. Of those, 140 (24.1%) were converted to inpatient status. The median age was 51 (IQR 44–59), and the median BMI was 28 kg/m2 (IQR 24–32). The XGBoost model showed the best performance with an AUC of 0.79. The most important features were the length of the operation, followed by sex (based on biological attributes), age, and operation start time. The logistic regression model and the SVM showed worse results, with an AUC of 0.71 each. ConclusionsThis study demonstrated a novel approach to predicting conversion to inpatient status in eligible patients for ambulatory surgery. The XGBoost model showed good predictive capabilities, superior to the older machine learning approaches. This model also revealed the importance of surgical duration time, BMI, and age as risk factors for patient conversion. A developing field of study is using machine learning in clinical decision-making. Our findings contribute to this field by demonstrating the feasibility and accuracy of such methods in predicting outcomes and identifying risk factors, although external and multi-center validation studies are needed.

What is the Marginal Intraoperative Cost of Using an Exoscope or Operative Microscope for Anterior Cervical Discectomy and Fusion? A Time-Driven Activity-Based Cost Analysis

Our primary objective was to compare the intraoperative costs of 3 different surgical visualization techniques for anterior cervical discectomy and fusion (ACDF). Specifically, we used time-driven activity-based costing (TDABC) methodology to compare costs between ACDFs performed with operative microscopes (OM-ACDF), exoscopes (EX-ACDF), and loupes (loupes-ACDF). Total cost was divided into direct and indirect costs. Individual costs were obtained by direct observation, electronic medical records, and through querying multiple departments (business operations, sterile processing, plant operations, and pharmacy). Timestamps for all involved personnel and material resources were documented. We identified all instances of loupes-ACDF (n= 882), EX-ACDF (n= 26), and OM-ACDF (n= 52) performed at our institution. We performed multivariable linear regression analyses to compare costs between these modalities, accounting for patient-specific factors as well as number of levels fused, surgeon, and hospital site. The average total intraoperative costs per loupes-ACDF, EX-ACDF, and OM-ACDF cases were $7081+/- $2,942, $7951+/- $3,488, and $6557+/- $954, respectively. Regression analysis revealed no difference in intraoperative cost between loupes-ACDF and EX-ACDF (P= 0.717), loupes-ACDF and OM-ACDF (0.954), or OM-ACDF and EX-ACDF (0.217). On a more granular level, however, EX-ACDF was associated with increased cost of consumables, including drapes, compared to both OM-ACDF (β-coefficient: $369+/- $121, P= 0.002) and loupes-ACDF (β-coefficient: $284+/- $86, P= 0.001). Although hospitals may be aware of the purchasing fees associated with microscopes and exoscopes, there is no clear documentation of how these technologies affect intraoperative cost. We demonstrate a novel use of TDABC for this purpose.

Overloaded vertebral body: a unique radiographic phenomenon following multilevel anterior cervical discectomy and fusion

PurposeBecause previous studies have not focused on postoperative cervical collapse, the purpose of the present study was to introduce the overloaded vertebral body (OVB) phenomenon following multilevel zero-profile anterior cervical discectomy and fusion (ACDF) as well as to investigate its effects on radiographic outcomes.MethodsWe conducted a retrospective study involving patients who underwent ACDF. A total of 55 patients were included in the analysis, including 110 OVB and 110 non-OVB. The evaluated vertebral parameters included the vertebral cross-sectional area (CSA), wedge angle (WA), vertebral height [anterior (AH) and posterior (PH)] and anterior–posterior vertebral diameter [upper (UD) and lower (LD)].ResultsThe CSA and WA were significantly lower in the OVB group than in the non-OVB group at 3, 6, and 12 months after surgery as well as at the final follow-up (p < 0.01). The AH of the OVB group was significantly lower at 3, 6, and 12 months after surgery as well as at the final follow-up compared to 1 week after surgery (p < 0.01).ConclusionsOVB, a new phenomenon following multilevel ACDF, is defined as the cervical vertebral body located in the middle of the surgical segments in multilevel anterior cervical spine surgery. Statistical analysis of vertebral parameters, including CSA, WA, AH, PH, UD, and LD, showed that OVB occurs mainly at the anterior edge of the vertebra and that its largest radiographic manifestation is the loss of height at the anterior edge of the vertebra in the early postoperative period.

FORAMINOTOMY VERSUS ACDF FOR PROXIMAL FORAMINAL STENOSIS

AbstractObjectivesThere is still controversy in the literature over whether Cervical Foraminotomy or Anterior Cervical discectomy and fusion (ACDF) is best for treating cervical Radiculopathy. Numerous studies have focused on the respective complication rates of these procedures and outcome measures with a lack of due consideration to preoperative MRI findings. Proximal foraminal stenosis can theoretically be accessed via either approach. We aimed to investigate whether patient reported outcome measures (PROMs) favoured one approach over the other in patients with proximal foraminal stenosis.MethodsA single centre retrospective review of patients undergoing either ACDF or Cervical foraminotomy over the period 2012 to 2022. VAS, Neck disability index (NDI), EQ5DL and Patient Satisfaction on a Five Point Likert scale were obtained. Patients who had both an ACDF and a Foraminotomy were excluded. Axial MRI images were analysed and the location of the worst clinically relevant disc herniation stratified as follows: Central (1), Paracentral (2) and Foraminal (3). Correlations and average PROMs were analysed in SPSS.ResultsPROMs scores were available for 33 ACDF patients and 37 Foraminotomy patients. Average surgery time in ACDF group was 167 minutes while Foraminotomy 142 minutes. Average Length of hospital stay was 6.24 days in the Foraminotomy group and 3.54 days in the ACDF group. 18 patients were excluded due to having both surgeries (2 of which developed CSF leaks postoperatively). Of the included patients there were no postoperative complications. 13 patients in the ACDF had Central or Paracentral stenosis in addition to proximal Foraminal stenosis, 3 patients in the Foraminotomy group had some significant Paracentral herniation just before the Proximal foramen. The majority of patients in both groups had pure proximal Foraminal stenosis (N= 17 (ACDF), 20 (Foraminotomy). The results showed no significant difference in PROMs between patients who received an ACDF or a Foraminotomy for Proximal foraminal stenosis (EQ5DL, NDI, and satisfaction, P= 0.268, 0.253 and 0.327). There was no correlation between location of the stenosis and PROM scores in either group.ConclusionsOur data suggest that Proximal foraminal stenosis can be effectively addressed by either an anterior ACDF or a Foraminotomy with no difference in complication rates. Foraminotomy has the benefit of no implant cost but longer hospital stay.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Early radiographic outcomes after anterior cervical discectomy and fusion with anatomic versus lordotic cages

BackgroundAnterior cervical discectomy and fusion (ACDF) interbody implants are shaped anatomically, with a convex superior aspect, or lordotically, with an angle and flat surfaces. However, the effect of implant shape on cervical sagittal balance (CSB) is not well described. MethodsOf the 192 cases reviewed from 2018 to 2019, 118 were included with matching pre- and postoperative imaging. Cases were categorized by interbody implant type (anatomic or lordotic) and number of levels fused (1-level, 2-level, etc.). SurgiMap was used to measure cervical lordosis (CL), C2–C7 sagittal vertical axis (cSVA), T1 slope (T1S), and T1S minus CL (T1S-CL) on pre- and postoperative imaging. Pre- and postoperative parameters were compared within and between each cohort. Change in CL (ΔCL), cSVA (ΔcSVA), and T1S-CL (ΔT1S-CL) were calculated as the difference between pre- and postoperative values and were compared accordingly (1) anatomic versus lordotic and (2) 1-level versus 2-level versus 3-level fusion. ResultsThirty-nine (33.1%), 57 (48.3%), and 22 (18.6%) cases comprised the anatomic, lordotic, and mixed (anatomic and lordotic) groups, respectively. ACDFs improved CL and T1S-CL by 5.71° (p<.001) and 3.32° (p<.01), respectively. CL was improved in the lordotic (5.27°; p<.01) and anatomic (4.57°; p<.01) groups, while only the lordotic group demonstrated improvement in T1S-CL (3.4°; p=.02). There were no differences in ΔCL (p=.70), ΔcSVA (p=.89), or ΔT1S-CL (p=.1) between the groups. Two- and 3-level fusions improved CL by 7.48° (p<.01) and 9.62° (p<.01), and T1S-CL by 4.43° (p<.01) and 5.96° (p<.01), respectively. ConclusionsOverall, ACDFs significantly improved CL and T1S-CL however, there were no differences in CSB correction between the anatomic and lordotic groups. Two- and 3-level fusions more effectively improved CL (vs. single-level) and T1S-CL (vs. 3-level). These results suggest that implants should continue to be personalized to the patient's anatomy, however, future research is needed to validate these findings and incorporate the effects of preoperative deformities.

Longer Screws Decrease the Risk of Radiographic Pseudarthrosis Following Elective Anterior Cervical Discectomy and Fusion.

Retrospective cohort study. In patients undergoing elective anterior cervical discectomy and fusion (ACDF), we sought to determine the impact of screw length on: (1) radiographic pseudarthrosis, (2) pseudarthrosis requiring reoperation, and (3) patient-reported outcome measures (PROMs). A single-institution, retrospective cohort study was undertaken from 2010-21. The primary independent variables were: screw length (mm), screw length divided by the anterior-posterior vertebral body diameter (VB%), and the presence of any screw with VB% < 75% vs all screws with VB% ≥ 75%. Multivariable logistic regression controlled for age, BMI, gender, smoking, American Society of Anesthesiology grade, number of levels fused, and whether a corpectomy was performed. Of 406 patients undergoing ACDF, levels fused were: 1-level (39.4%), 2-level (42.9%), 3-level (16.7%), and 4-level (1.0%). Mean screw length was 14.3 ± 2.3mm, and mean VB% was 74.4 ± 11.2. A total of 293 (72.1%) had at least one screw with VB% < 75%, 113 (27.8%) had all screws with VB% ≥ 75%, and 141 (34.7%) patients had radiographic pseudarthrosis at 1-year. Patients who had any screw with VB% < 75% had a higher rate of radiographic pseudarthrosis compared to those had all screws with VB% ≥ 75% (39.6% vs 22.1%, P < .001). Multivariable logistic regression revealed that a higher VB% (OR = .97, 95%CI = .95-.99, P = .035) and having all screws with VB% ≥ 75% (OR = .51, 95%CI = .27-.95, P = .037) significantly decreased the odds of pseudarthrosis at 1-year, with no difference in reoperation or PROMs (all P > .05). Longer screws taking up ≥75% of the vertebral body protected against radiographic pseudarthrosis at 1-year. Maximizing screw length in ACDF is an easily modifiable factor directly under the surgeon's control that may mitigate the risk of pseudarthrosis.

Prospective, multicenter clinical trial comparing the M6-C compressible cervical disc with anterior cervical discectomy and fusion for the treatment of single-level degenerative cervical radiculopathy: 5-year results of an FDA investigational device exemption study

BACKGROUND CONTEXTVarious total disc replacement (TDR) designs have been compared to anterior cervical discectomy and fusion (ACDF) with favorable short and long-term outcomes in FDA-approved investigational device exemption (IDE) trials. The unique design of M6-C, with a compressible viscoelastic nuclear core and an annular structure, has previously demonstrated favorable clinical outcomes through 24 months. PURPOSETo evaluate the long-term safety and effectiveness of the M6-C compressible artificial cervical disc and compare to ACDF at 5 years. STUDY DESIGNProspective, multicenter, concurrently and historically controlled, FDA-approved IDE clinical trial. PATIENT SAMPLESubjects with one-level symptomatic degenerative cervical radiculopathy were enrolled and received M6-C (n=160) or ACDF (n=189) treatment as part of the IDE study. Safety outcomes were evaluated at 5 years for all subjects. The primary effectiveness endpoint was available at 5 years for 113 M6-C subjects and 106 ACDF controls. OUTCOME MEASURESThe primary endpoint of this analysis was composite clinical success (CCS) at 60 months. Secondary endpoints were function and pain (neck disability index, VAS), physical quality of life (SF-36, SF-12), safety, neurologic, and radiographic assessments. METHODSPropensity score subclassification was used to control for selection bias and match baseline covariates of the control group to the M6-C subjects. Sixty-month CCS rates were estimated for each treatment group using a generalized linear model controlling for propensity score. RESULTSAt 5 years postoperatively, the M6-C treatment resulted in 82.3% CCS while the ACDF group showed 67.0% CCS (superiority p=.013). Secondary endpoints indicated that significantly more M6-C subjects achieved VAS neck and arm pain improvements and showed maintained or improved physical functioning on quality-of-life measures compared to baseline assessments. The M6-C group-maintained flexion-extension motion, with significantly greater increases from baseline disc height and disc angle than observed in the control group. The rates of M6-C subsequent surgical interventions (SSI; 3.1%) and definitely device- or procedure-related serious adverse events (SAE failure; 3.1%) were similar to ACDF rates (SSI=5.3%, SAE failure=4.8%; p>.05 for both). CONCLUSIONSSubjects treated with the M6-C artificial disc demonstrated superior 5-year achievement of clinical success when compared to ACDF controls. In addition, significantly more subjects in the M6-C group showed improved pain and physical functioning scores than observed in ACDF subjects, with no difference in reoperation rates or safety outcomes.

Preoperative Radiographic Simulation for Partial Uncinate Process Resection during Anterior Cervical Discectomy and Fusion to Achieve Adequate Foraminal Decompression and Prevention of Vertebral Artery Injury.

Retrospective radiographic study. This study aims to demonstrate the proper resection trajectory of a partial posterior uncinate process resection combined with anterior cervical discectomy and fusion (ACDF) and evaluate whether foraminal stenosis or uncinate process degeneration increases the risk of vertebral artery (VA) injury. Appropriate resection trajectory that could result in sufficient decompression and avoid vertebral artery injury is yet unknown. We retrospectively reviewed patients who underwent cervical magnetic resonance imaging and computed tomography angiography for preoperative ACDF evaluation. The segments were classified according to the presence of foraminal stenosis. The height, thickness, anteroposterior length, horizontal distance from the uncinate process to the VA, and vertical distance from the uncinate process baseline to the VA of the uncinate process were measured. The distance between the uncinate anterior margin and the resection trajectory (UAM-to-RT) was measured. There were no VA injuries or root injuries among the 101 patients who underwent ACDF (163 segments, mean age of 56.3±12.2). Uncinate anteroposterior length was considerably longer in foramens with foraminal stenosis, whereas uncinate process height, thickness, and distance between the uncinate process and VA were not significantly associated with foraminal stenosis. There were no significant differences in radiographic parameters based on uncinate degeneration. The UAM-to-RT distances for adequate decompression were 1.6±1.4 mm (range, 0-4.8 mm), 3.4±1.7 mm (range, 0-7.1 mm), 4.0±1.7 mm (range, 0-9.0 mm), and 4.5±1.2 mm (range, 2.5-7.5 mm) for C3-C4, C4-C5, C5-C6, and C6-C7, respectively. More than half of the uncinate process in the anteroposterior plane should be removed for adequate neural foramen decompression. Foraminal stenosis or uncinate degeneration did not alter the relative anatomy of the uncinate process and the VA and did not impact VA injury risk.

Outpatient Spine Procedures in Poland: Clinical Outcomes, Safety, Complications, and Technical Insights into an Ambulatory Spine Surgery Center.

This study evaluated the safety and efficacy of spine procedures performed in an ambulatory spine surgery unit in Poland. We conducted a retrospective analysis of 318 patients who underwent ambulatory spine surgery between 2018 and 2021, with procedures including microdiscectomy (MLD), anterior cervical discectomy and fusion (ACDF), endoscopic interbody fusion (endoLIF), posterior endoscopic cervical discectomy (PECD), interlaminar endoscopic lumbar discectomy IELD, and transforaminal endoscopic lumbar discectomy (TELD). Patient data were analyzed for pre-operative and post-operative visual analog scale (VAS) scores. The findings indicated that outpatient techniques were safe and effective, with a 2.83% complication rate. All procedures significantly improved VAS scores under short-term observation, and core outcome measurement index (COMI) scores under long-term observation. Ambulatory spine surgery represents a relatively new approach in Poland, with only a select few centers currently offering this type of service. Outpatient spine surgery is a safe, effective, and cost-effective option for patients requiring basic spine surgeries.

The Incidence of Vertebral Artery Injury in Cervical Spine Surgery

Study DesignRetrospective Cohort Study ObjectiveThe purpose of this study is to identify the incidence of vertebral artery injuries (VAI) in patients undergoing cervical spine procedures for degenerative pathologies. Summary of Background DataPreviously reported estimates of VAI during cervical spine surgery relied upon self-reported survey studies and retrospective cohorts which may not be reflective of national averages. The largest study to date reports an incidence of 0.07%; however, significant variation exists between different cervical spine procedures. MethodsA national insurance database was used to access patient data from 2010-2020, who underwent Anterior Cervical Discectomy and Fusion (ACDF), Anterior Corpectomy, Posterior Cervical Fusion (C3-C7), or C1-C2 posterior fusions for degenerative pathologies. Patients who experienced a vertebral artery injury were identified and frequencies for the different procedures were compared. ResultsA total of 224,326 patients were included in this study and the overall incidence of VAI across all procedures was found to be 0.03%. The highest incidence of VAI was estimated in C1-C2 posterior fusion (0.12-1.10%). The number of VAI cases post anterior corpectomy, ACDF, and posterior fusion were 14 (0.06), 43 (0.02) and 26 (0.01) patients respectively. ConclusionsThis is the largest study to date that provides frequencies of vertebral artery injuries in patients undergoing cervical spine surgery in the United States. Our finding of 0.03% is lower than previously reported estimates but significant variability exists between procedures which is important to counsel patients when discussing risks of surgery.

Comparison between 3-level and 4-level anterior cervical discectomy and fusion in the treatment of cervical spondylotic myelopathy: A meta-analysis

ObjectiveOur objective is to estimate the clinical effectiveness of 3-level and 4-level anterior cervical discectomy and fusion (ACDF) in the management of cervical spondylotic myelopathy (CSM). MethodsWe conducted a thorough search in English databases. We gathered the data on surgical variables and complications to contrast the clinical effectiveness between 3-level and 4-level. We utilized RevMan 5.3 and STATA 12.0 to analyze the data. ResultsFinally, eight studies met inclusion criteria of this study. Our findings indicated that operation time [p for heterogeneity = 0.23, I2 = 32 %, p＜0.00001, OR = −24.93, 95%CI (−32.39,-17.49)], blood loss [p for heterogeneity = 0.33, I2 = 10 %, p＜0.00001, OR = −60.87, 95%CI (−85.43,-36.32)] and the total number of complications [p for heterogeneity = 0.36, I2 = 0 %, p = 0.004, OR = 0.37, 95%CI (0.18,0.72)] in 3-level ACDF were significantly less than in 4-level ACDF. No marked difference was found in hospital stay, revision rate, fusion rate, the number of readmissions, infection, hematoma, or pseudarthrosis between 3-level and 4-level ACDF. ConclusionsIt is easy to understand that performing 4-level needs more operation time and blood loss. No obvious discrepancy was found with regard to the subgroups of complications between the two procedures, yet 4-level procedures had a more number of complications.

The Veterans Rand-12 Physical Composite Score Prognosticates Postoperative Clinical Outcomes in Patients Undergoing Anterior Cervical Discectomy and Fusion

To determine prognostic value of preoperative Veterans RAND 12-Item Health Survey (VR-12) physical composite score (PCS) on outcomes in patients undergoing anterior cervical discectomy and fusion (ACDF). ACDF patients with preoperative VR-12 PCS formed 2 cohorts: VR-12 PCS <35 and VR-12 PCS ≥35. The following patient-reported outcome measures (PROMs) were gathered preoperatively and postoperatively up to 2 years: VR-12 mental composite score (MCS)/PCS, Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System (PROMIS) PF, 9-Item Patient Health Questionnaire (PHQ-9), visual analog scale (VAS) neck/arm pain, and 12-Item Short Form Health Survey (SF-12) PCS/MCS. Comparing PROMs change with established thresholds determined achievement of minimum clinically important difference (MCID). Univariate analysis compared demographics, perioperative characteristics, and preoperative PROMs. Multivariable regression analysis compared postoperative PROMs and MCID achievement. Of 174 patients, 83 had VR-12 PCS <35. Preoperatively, patients with reduced PF displayed lower patient-reported outcome scores in NDI, PHQ-9, and SF-12 MCS (P ≤ 0.008), but not in VAS arm. At 6 weeks postoperatively, these patients continued to score lower in NDI (P ≤ 0.014) and SF-12 PCS (P ≤ 0.001), among others. By the final check, most scores remained lower (P ≤ 0.002) except for PHQ-9 and VAS arm (P > 0.05). Greater improvements at 6 weeks postoperatively were especially noted in patients with lower initial VR-12 PCS for NDI, PROMIS PF, and SF-12 PCS (P < 0.05). However, by final follow-up, only PROMIS PF showed noteworthy improvement (P= 0.19). Regarding MCID achievement, significant differences were largely absent except in NDI, where patients with reduced PF exhibited more MCID achievement (P= 0.016). ACDF patients with VR-12 PCS <35 experienced inferior PF, mental health, and disability postoperatively until final follow-up. There were no significant differences in postoperative improvement magnitude and MCID achievement. Results suggest that baseline VR-12 PCS in ACDF patients may indicate poorer PF, mental health, and disability postoperatively. However, VR-12 PCS does not limit extent of postoperative improvement.

Anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord via one vertebra with two bony channels for adjacent two-segment cervical spondylotic myelopathy: a technical note

BackgroundThe current treatments for adjacent two-segment cervical spondylotic myelopathy (CSM) include two-segment anterior cervical discectomy and fusion (ACDF) and single-segment anterior cervical corpectomy and fusion (ACCF). Long-term follow-up has demonstrated that both procedures have complications such as reduced cervical mobility, accelerated degeneration of adjacent segments and loosening of internal fixation screws. The purpose of this study is to demonstrate the feasibility, safety, and efficacy of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels for the treatment of adjacent two-segment CSM and to present our surgical experience.MethodsAnterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels was performed for 12 patients with adjacent two-segment CSM with follow-up care for at least 12 months. The Visual analog scale (VAS) and the Japanese Orthopedic Association Score (JOA) were recorded, and modified Macnab criteria were used to evaluate the treatment excellence rate. Radiological examinations, including X-ray, computed tomography (CT) and magnetic resonance imaging (MRI), were used to evaluate spinal cord decompression, intervertebral stability and healing of the bony channel.ResultsAll 12 patients completed the operation successfully. No postoperative complications, such as dysphagia, Horner’s syndrome, or laryngeal recurrent nerve palsy, were found. The postoperative VAS and JOA scores were significantly improved compared with those before surgery(P < 0.001). According to the modified Macnab criteria, the clinical outcome was excellent in 8 cases, good in 3 cases and fine in 1 case at the final follow-up and the excellent and good rate was 91.7%. Postoperative and follow-up imaging showed significant spinal cord decompression, well-healed bony channels and no cervical instability.ConclusionsThis study is the first report of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord via one vertebra with two bony channels. This procedure has the advantages of less trauma, faster recovery, fewer complications and no need to implant internal fixators. This is a minimally invasive, feasible and safe surgical procedure for patients with adjacent two-segment CSM.