Level Anterior Cervical Discectomy And Fusion Research Articles

Are Variable Screw Angle Change and Screw-to-Vertebral Body Ratio Associated With Radiographic Subsidence Following Anterior Cervical Discectomy and Fusion?

Retrospective Cohort. This study aims to assess the easily measurable radiographic landmarks of screw-to-vertebral body ratio and changes in screw angle to identify if they are associated with early subsidence following an Anterior cervical discectomy and fusion (ACDF). A retrospective cohort study was conducted on patients undergoing 1-3 level ACDF with allograft or PEEK cages. Preoperative, immediate postoperative, and 6-month postoperative radiographs were analyzed to measure intradiscal height (or distance between 2 vertebral bodies) as an anterior vertebral distance (AVD), middle (MVD), and posterior (PVD), screw angle, screw-to-vertebral body length ratio, and interscrew distance. Multivariate stepwise regression analyses were performed. 92 patients were included (42 single-level, 32 two-level, and 18 3-level ACDFs). In single-level ACDFs, a decrease in the caudal screw angle was associated with a decrease in AVD (=.001) and MVD (P = .03). A decrease in the PVD was associated with a decrease in segmental lordosis (P < .001). For two-level ACDFs, a higher caudal screw-to-body ratio was associated with a lower MVD (P = .01). Six months following an ACDF for degenerative pathology, a decrease in the caudal screw angle was associated with an increase in radiographic subsidence at the antero-medial aspect of the disc space albeit largely subclinical. This suggests that the caudal screw angle change may serve as a reliable radiographic marker for early radiographic subsidence. Furthermore, a greater screw-to-vertebral body ratio may be protective against radiographic subsidence in two-level ACDF procedures.

MRI Vertebral Bone Quality Correlates With Interbody Cage Subsidence After Anterior Cervical Discectomy and Fusion.

Retrospective observational study of consecutive patients. The purpose of the study was to evaluate VBQ as a predictor of interbody subsidence and to determine threshold values that portend increased risk of subsidence. Many risk factors have been reported for the subsidence of interbody cages in anterior cervical discectomy and fusion (ACDF). MRI Vertebral Bone Quality (VQB) is a relatively new radiographic parameter that can be easily obtained from preoperative MRI and has been shown to correlate with measurements of bone density such as DXA and CT Hounsfield Units. All patients who underwent 1- to 3-level ACDF using titanium interbodies with anterior plating between the years 2018 and 2020 at our tertiary referral center were included. Subsidence measurements were performed by 2 independent reviewers on CT scans obtained 6 months postoperatively. VBQ was measured on pre-operative sagittal T1 MRI by 2 independent reviewers, and values were averaged. Eight-five fusion levels in 44 patients were included in the study. There were 32 levels (38%) with moderate subsidence and 12 levels with severe subsidence (14%). The average VBQ score in those patients with severe subsidence was significantly higher than those without subsidence (3.80 vs. 2.40, P<0.01). A threshold value of 3.2 was determined to be optimal for predicting subsidence (AUC=0.99) and had a sensitivity of 100% and a specificity of 94.1% in predicting subsidence. VBQ strongly correlates with the subsidence of interbody grafts after ACDF. A threshold VBQ score value of 3.2 has excellent sensitivity and specificity for predicting subsidence. Spine surgeons can use VBQ as a readily available screening tool to identify patients at higher risk for subsidence. Level-IV.

1076 3-Level ACDF Versus 3-Level Laminectomy and Fusion: Are There Differences in Outcomes? An Analysis of the QOD CSM Cohort

INTRODUCTION: Prior studies comparing anterior versus posterior approaches for multilevel cervical spondylotic myelopathy (CSM) are limited by the heterogeneity of levels operated. METHODS: The prospective QOD CSM cohort was queried for fusions across only three interspaces. Surgeries crossing the cervicothoracic junction were excluded. The cohort was divided into anterior cervical discectomy and fusion (ACDF) and posterior laminectomy-and-fusion. 24-month patient-reported outcomes were compared. RESULTS: Of 199 patients (123 ACDF, 76 posterior fusions), 24-month follow-up rates were similar (ACDF: 90.2% vs. 92.1%, p = 0.67). Preoperatively, ACDF were younger (60.8 ± 10.2 vs. 65.0 ± 10.3 yr, p &lt; 0.01), used more private insurance (56.1% vs. 36.8%, p = 0.02), were more often employed (39.8% vs. 22.8%, p = 0.04), and independently ambulatory (14.6% vs. 31.6%, p &lt; 0.01). Otherwise, the cohorts had equivalent baseline mJOA, NDI, NRS Arm-Pain, NRS Neck-Pain, and EQ-5D (p &gt; 0.05). ACDF had shorter hospitalizations (1.6 vs. 3.9 days, p &lt; 0.01) and less non-routine discharge (7.3% vs. 22.8%, p &lt; 0.01) but higher postoperative dysphagia (13.5% vs. 3.5%, p = 0.049). Both groups demonstrated improvements in all outcomes at 24 months (p &lt; 0.05). In multivariable analyses, ACDF was associated with the greatest 24-month NASS Satisfaction (NASS 1)(69.4% vs. 53.7%, OR = 2.44, p = 0.02). Otherwise, the cohorts shared similar 24-month patient-reported outcomes. There were no differences in 3-month readmission (4.1% ACDF vs. 3.9% posterior fusion, p = 0.97) and 24-month reoperation rate (13.5% ACDF vs. 18.6% posterior fusion, p = 0.36). CONCLUSIONS: In a cohort limited to 3-level surgeries, ACDF was associated with reduced blood loss, shorter lengths of hospitalization, and higher routine discharge rates; however, posterior cervical fusion resulted in less dysphagia. After controlling for confounders, the ACDF cohort had a significantly higher odds of maximum satisfaction. Patients should be counseled on the risks and benefits of each approach, given relatively comparable outcomes.

Are Patients With Segmental Cervical Kyphosis Appropriate Candidates for Cervical Disc Arthroplasty (CDA)? A Clinical and Radiographic Analysis Compared to Anterior Cervical Discectomy and Fusion (ACDF).

Retrospective cohort study. To compare the clinical and radiographic outcomes of Anterior Cervical Discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) in patients with preoperative segmental kyphosis. Patients with segmental cervical kyphosis at the operative levels undergoing 1- or 2-level ACDF or CDA from 2017 to 2020 with 2years of follow were identified. Patient demographics, perioperative data, complication rates, radiographic findings and reported outcomes were analyzed. A total of 48 patients met inclusion criteria and were included in our study (ACDF: n = 24, CDA: n = 24). Patient demographic data between the 2 cohorts was similar expect for proportion of males (ACDF: 62.5% vs CDA: 33.3%, P = .043). There was no statistical significance in the change of segmental lordosis (ACDF: +8.09° vs CDA: +5.88°, P = .075) between the preoperative and final postoperative period. Additionally, the change in cervical lordosis was similar between groups (ACDF:+ 9.86° vs CDA: +7.60°, P = .226). VAS scores were similar between the 2 groups at every follow-up interval. NDI scores were significantly different at the 6-month, 12 month and the final follow-up. Mean improvements between preoperative and final postoperative periods were statistically superior in the CDA cohort compared to the ACDF cohort (ACDF: 22.8 vs CDA: 24.1, P = .0375). CDA was superior to ACDR in regards to NDI scores following index procedure in patients with preoperative segmental cervical kyphosis. Those in the CDA cohort had similar complication rates, revision rates and radiographic outcomes as those who underwent ACDF.

Structural Allograft Versus Mechanical Interbody Devices Augmented With Osteobiologics in Anterior Cervical Discectomy and Fusion: A Systematic Review.

Systematic Literature Review. Perform a systematic review evaluating postoperative fusion rates for anterior cervical discectomy and fusion (ACDF) using structural allograft vs various interbody devices augmented with different osteobiologic materials. Comprehensive literature search using PubMed, Embase, The Cochrane Library, and Web of Science was performed. Included studies were those that reported results of 1-4 levels ACDF using pure structural allograft compared with a mechanical interbody device augmented with an osteobiologic. Excluded studies were those that reported on ACDF with cervical corpectomy; anterior and posterior cervical fusions; circumferential (360° or 540°) fusion or revision ACDF for nonunion or other conditions. Risk of bias was determined using the Cochrane review guidelines. 8 articles reporting fusion rates of structural allograft and an interbody device/osteobiologic pair were included. All included studies compared fusion rates following ACDF among structural allograft vs non-allograft interbody device/osteobiologic pairs. Fusion rates were reported between 84% and 100% for structural allograft, while fusion rates for various interbody device/osteobiologic combinations ranged from 26% to 100%. Among non-allograft cage groups fusion rates varied from 73-100%. One study found PEEK cages filled with combinations of autograft, allograft, and demineralized bone matrix (DBM) to have an overall fusion rate of 26%. In one study comparing plate and zero-profile constructs, there was no difference in fusion rates for two-level fusions. There was limited data comparing fusion outcomes of patients undergoing ACDF using structural allograft vs interbody devices augmented with osteobiologic materials to support superiority of one method.

The Use of Osteobiologics in Single versus Multi-Level Anterior Cervical Discectomy and Fusion: A Systematic Review.

Systematic literature review. In this study we assessed evidence for the use of osteobiologics in single vs multi-level anterior cervical discectomy and fusion (ACDF) in patients with cervical spine degeneration. The primary objective was to compare fusion rates after single and multi-level surgery with different osteobiologics. Secondary objectives were to compare differences in patient reported outcome measures (PROMs) and complications. After a global team of reviewers was selected, a systematic review using different repositories was performed, confirming to PRISMA and GRADE guidelines. In total 1206 articles were identified and after applying inclusion and exclusion criteria, 11 articles were eligible for analysis. Extracted data included fusion rates, definition of fusion, patient reported outcome measures, types of osteobiologics used, complications, adverse events and revisions. Fusion rates ranged from 87.7% to 100% for bone morphogenetic protein 2 (BMP-2) and 88.6% to 94.7% for demineralized bone matrix, while fusion rates reported for other osteobiologics were lower. All included studies showed PROMs improved significantly for each osteobiologic. However, no differences were reported when comparing osteobiologics, or when comparing single vs multi-level surgery specifically. The highest fusion rates after 2-level ACDF for cervical spine degeneration were reported when BMP-2 was used. However, PROMs did not differ between the different osteobiologics. Further blinded randomized trials should be performed to compare the use of BMP-2 in single vs multi-level ACDF specifically.

Analysis of Complications in Multilevel Anterior Cervical Discectomy and Fusion Using Osteobiologics Other than Bone Morphogenetic Protein: A Systematic Review.

Systematic review. The aim of this study is to analyze the complications related to multilevel anterior cervical discectomy and fusion (ACDF) using osteobiologics other than bone morphogenetic protein (BMP). A systematic review of the literature was conducted using PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov databases. The search to identify studies reporting complications in multilevel ACDF surgery using osteobiologics other than bone morphogenetic protein was performed in August 2020. The study was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). A total of 584 articles were found after searching the databases and removing duplicates. Next, screening was performed in a double reviewer process, and 153 eligible articles-with 4 retrospective studies-in full-text were selected; these met all inclusion criteria. A total of 197 patients received 3-level ACDF, while 72 patients received 4-level ACDF. Osteobiologics were used in all selected articles, allograft was used in 4 studies, autologous bone graft was utilized in 3 articles, and hydroxyapatite was used in 1 article. The main complications reported were dysphagia, adjacent segment disease, and pseudarthrosis. Given the limited evidence, no conclusions on complications in multilevel ACDF using osteobiologics other than BMP could be made. However, descriptively, the most common complications found were dysphagia, adjacent segment disease, and pseudoarthrosis. Further prospective studies separately analyzing complications in multilevel ACDF by osteobiologics and a number of treated levels are needed.

A Comparison between Structural Allografts and Polyetheretherketone Interbody Spacers Used in Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-analysis.

Among interbody implants used during anterior cervical discectomy and fusion (ACDF), structural allografts and polyetheretherketone (PEEK) are the most used spacers. Currently, no consensus has been established regarding the superiority of either implant, with US surgeons preferring structural allografts, whereas UK surgeons preferring PEEK. The purpose of this systematic review (level of evidence, 4) was to compare postoperative and patient-reported outcomes between the use of structural allografts PEEK interbody spacers during ACDF. Five electronic databases (PubMed, Embase, Scopus, Web of Science, and Cochrane) were searched for articles comparing the usage of structural allograft and PEEK interbody spacers during ACDF procedures from inception to April 10, 2023. The searches were conducted using the keywords "Spine," "Allograft," and "PEEK" and were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Subsequent quality and sensitivity analyses were performed on the included studies. Nine studies involving 1,074 patients were included. Compared with the PEEK group, the structural allograft group had comparable rates of postoperative pseudoarthrosis (p=0.58). However, when stratified according to the number of levels treated, the 3-level ACDF PEEK group was 3.45 times more likely to have postoperative pseudoarthrosis than the structural allograft group (p=0.01). Subsequent postoperative outcomes (rate of subsidence and change in the preoperative and postoperative segmental disc heights) were comparable between the PEEK and structural allograft groups. Patient-reported outcomes (Visual Analog Scale [VAS] of neck pain and Neck Disability Index [NDI]) were comparable. This study showed that for 3-level ACDFs, the use of structural allografts may confer higher fusion rates. However, VAS neck pain, NDI, and subsidence rates were comparable between structural allografts and PEEK cages. In addition, no significant difference in pseudoarthrosis rates was found between PEEK cages and structural allografts in patients undergoing 1- and 2-level ACDFs.

A Comparison between Structural Allografts and Polyetheretherketone Interbody Spacers Used in Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-analysis.

Among interbody implants used during anterior cervical discectomy and fusion (ACDF), structural allografts and polyetheretherketone (PEEK) are the most used spacers. Currently, no consensus has been established regarding the superiority of either implant, with US surgeons preferring structural allografts, whereas UK surgeons preferring PEEK. The purpose of this systematic review (level of evidence, 4) was to compare postoperative and patient-reported outcomes between the use of structural allografts PEEK interbody spacers during ACDF. Five electronic databases (PubMed, Embase, Scopus, Web of Science, and Cochrane) were searched for articles comparing the usage of structural allograft and PEEK interbody spacers during ACDF procedures from inception to April 10, 2023. The searches were conducted using the keywords "Spine," "Allograft," and "PEEK" and were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Subsequent quality and sensitivity analyses were performed on the included studies. Nine studies involving 1,074 patients were included. Compared with the PEEK group, the structural allograft group had comparable rates of postoperative pseudoarthrosis (p=0.58). However, when stratified according to the number of levels treated, the 3-level ACDF PEEK group was 3.45 times more likely to have postoperative pseudoarthrosis than the structural allograft group (p=0.01). Subsequent postoperative outcomes (rate of subsidence and change in the preoperative and postoperative segmental disc heights) were comparable between the PEEK and structural allograft groups. Patient-reported outcomes (Visual Analog Scale [VAS] of neck pain and Neck Disability Index [NDI]) were comparable. This study showed that for 3-level ACDFs, the use of structural allografts may confer higher fusion rates. However, VAS neck pain, NDI, and subsidence rates were comparable between structural allografts and PEEK cages. In addition, no significant difference in pseudoarthrosis rates was found between PEEK cages and structural allografts in patients undergoing 1- and 2-level ACDFs.

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.

Clinical and Radiographic Outcomes for Patients with Cervical Adjacent Segment Disease Treated with Anterior Cervical Discectomy and Fusion with Integrated Interbody Spacers

Anterior cervical discectomy and fusion (ACDF) is among the most common spine procedures. Adjacent segment disease (ASD), characterized by degenerative disease at an adjacent spinal level to a prior fusion, is a well-recognized and significant sequela following ACDF. Adjacent segment ACDF may be considered after the failure of non-surgical options for patients with symptomatic ASD. This study aimed to assess the incidence of dysphagia and other complications as well as radiographic outcomes in adult patients who have undergone ACDF with an integrated interbody spacer device for symptomatic ASD. This was a retrospective review of patients who underwent ACDF for symptomatic ASD with commercially available integrated interbody spacers by three spine surgeons at an academic institution from March 2018 to April 2022. Demographic, radiographic, and postoperative data were collected, including dysphagia, device-related complications, and the need for revision surgery. There were 48 patients (26 male, 22 female) who met inclusion criteria (mean age 59.7 years, mean body mass index 19.5 kg/m2) who underwent ACDF for symptomatic ASD (1one-level, n= 44; 2-level, n= 4). Overall, 12 patients (25%) experienced dysphagia postoperatively before the first follow-up appointment. Nine of 44 (20.4%) of 1-level ACDF patients experienced dysphagia, and 3 of 4 (75%) of 2-level ACDF patients experienced dysphagia. Three patients had severe dysphagia which prompted an otolaryngology referral. Two of those patients remained symptomatic at 6 weeks postoperatively. Of 43 patients with prior plate cage systems, none required hardware removal at the time of surgery. Preoperative global and segmental lordosis were 9.07° ± 8.36° (P= 0.22) and 3.58° ± 4.57° (P= 0.14), respectively. At 6 weeks postoperatively, global and segmental lordosis were 11.44° ± 9.06° (P= 0.54) and 5.11° ± 4.44° (P= 0.44), respectively. This constitutes a change of+2.37° and+1.53° in global and segmental lordosis, respectively. The mean anterior disc height change between preoperative and immediate postoperative time points was 6.3 ± 3.1 mm. Between the immediate postoperative and 6-week postoperative time points, the mean anterior disc height change was -1.5 ± 2.7 mm. Between the immediate postoperative and 3-month postoperative time points, the mean anterior disc height change was -3.7 ± 5.0 mm. The posterior disc height changes at the same time points were 2.5 ± 1.7 mm, -0.4 ± 1.8. and -0.5 ± 1.4 mm, respectively. This fusion rate was 50% and 70% at 6 months and 1 year post-surgery, respectively. ACDF with integrated spacer is a viable alternative to traditional plate-cage systems for symptomatic ASD. An advantage over traditional plate-cage systems is that the removal of prior instrumentation is not needed in order to place implants. Based on a review of the literature, these standalone systems allowed for a shorter operative time and had less incidence of dysphagia than plate-cage systems for ASD after ACDF. The different standalone and plate-cage systems used in treating ASD after ACDF surgeries should be compared in prospective studies.

Anterior Cervical Discectomy and Fusion With Structural Allograft is Associated With Lower Postoperative Health Care Utilization and Reoperations Compared With Cage Implants.

Implants represent a large component of surgical cost, with several available options for anterior cervical discectomy and fusion (ACDF). Rising ACDF volume highlights the need for accurate cost characterization among implant configurations to inform efficient utilization. A cohort study of patients who underwent 1-level or 2-level ACDF in 2017 was conducted using the MarketScan national insurance databases, which contain deidentified clinical and financial data. Implant configurations included plate with cage, standalone cage, and plate with structural allograft. Patients who switched insurance providers within 2 years after surgery or underwent concurrent posterior cervical surgery, cervical disk arthroplasty, or cervical corpectomy were excluded. A combined plate/cage and standalone cage group was compared with the allograft group followed by the comparison of the plate/cage and standalone cage groups. In total, 30-day, 90-day, and 2-year aggregate costs; component costs of physical therapy, injections, medications, psychological treatment, and subsequent spine surgery; and reoperation rates were evaluated. Of 1723 patients identified, 360 (20.9%) underwent surgery with plate/cage, 184 (10.7%) with standalone cage, and 1179 (68.4%) with allograft. Aggregate costs were lower in the allograft group compared with the combined cage group at 90 days ($36 428 vs $39 875, P = .04) and 2 years ($64 951 vs $74 965, P = .005) postoperatively. There were no significant differences in aggregate costs between the plate/cage and standalone cage groups. The 2-year reoperation rate was higher in the combined cage compared with the allograft group (23.9% vs 10.9%, P < .001) and was also higher in the standalone cage compared with the plate/cage group (32.0% vs 19.7%, P = .002). Compared with alternative ACDF constructs, allograft is associated with lower postoperative costs and reoperation rates. Although costs are similar, reoperation rates are lower with plate/cage constructs compared with those of standalone cages. Surgeons should consider these financial and clinical differences when selecting implant configurations.

Synthetic Interbody Devices and Traditional Bone Graft Are Associated With a Similar Rate of Surgical Complications After 1-2 Level Anterior Cervical Discectomy and Fusions.

Retrospective cohort. To compare the rates of all-cause surgical complications of synthetic interbody devices versus allograft or autograft in patients undergoing 1-2 levels anterior cervical discectomy and fusion (ACDF) procedures. Cervical degenerative disorders affect up to 60% of older adults in the United States. Both traditional allograft or autograft and synthetic interbody devices (polyetheretherketone or titanium) are used for decompression and arthrodesis, with increasing utilization of the latter. However, the differences in their postsurgical complication profiles are not well-characterized. Patients who underwent 1-2 level ACDFs for cervical radiculopathy or myelopathy between 2010 and 2022 were identified using the PearlDiver Mariner all-claims insurance database. Patients undergoing surgery for nondegenerative pathologies, such as tumors, trauma, or infection, were excluded. 1:1 exact matching was performed based on factors that were significant predictors of all-cause surgical complications in a linear regression model. The primary outcome measure was the development of all-cause surgical complications after 1-2 level ACDFs. The secondary outcome was all-cause medical complications. 1:1 exact matching resulted in two equal groups of 11,430 patients who received treatment with synthetic interbody devices or allograft/autograft. No statistically significant difference in all-cause surgical complications was found between the synthetic cohort and the allograft or autograft cohort after 1-2 level ACDFs (Relative Risk: 0.86, 95% confidence interval: 0.730-1.014, P = 0.079). No significant differences were observed regarding any specific surgical complications except for pseudoarthrosis (Relative Risk: 0.73, 95% confidence interval: 0.554-0.974, P = 0.037), which was higher in the allograft/autograft cohort. After 1:1 exact matching to control for confounding variables, the findings of this study suggest that all-cause surgical complications are similar in patients undergoing ACDFs with synthetic interbody devices or allograft/autographs. However, the rate of pseudarthrosis appears to be higher in patients with allograft/autographs. Future prospective studies are needed to corroborate these findings.

No Difference in Surgical Outcomes between Stand-Alone Devices and Anterior Plating for 1-2 level Anterior Cervical Discectomy and Fusion: A 1:1 Exact Matched Analysis.

Retrospective cohort. Compare rates of all-cause surgical and medical complications between zero-profile (stand-alone) implants versus any graft type with anterior plate in patients undergoing 1-2 level anterior cervical discectomy and fusion (ACDF) for treatment of degenerative cervical myeloradiculopathy. Degenerative cervical myeloradiculopathy is increasingly prevalent in older adults. ACDF is a common surgical procedure for decompression of neural structures and stabilization and has been shown to have excellent outcomes. While ACDFs performed with a graft and plate has been the gold standard, more recently, zero-profile implants were developed to decrease implant related complications, such as severe postoperative dysphagia. However, there is a paucity of papers comparing the surgical and medical complications profile of zero-profile (stand-alone) implants to grafts with plating systems. Data was extracted from the PearlDiver Mariner Database using CPT codes to classify patients into 1-level, 2-levels, and total 1-2 level ACDFs. Patients undergoing surgery for non-degenerative pathologies such as tumors, trauma, or infection were excluded. 1:1 exact matching created two equal groups of 7,284 patients that underwent 1-2 level ACDF with either grafting with a plate or zero-profile (standalone) implant. There were no statistically significant difference in all-cause surgical complications, pseudarthrosis rate, dysphagia or need for revision surgery between both cohorts (RR 0.99, 95% CI 0.80-1.21, P = 0.95). Additionally, all-cause medical complications were similar between both cohorts (RR 1.07, 95% CI 0.862-1.330, P = 0.573) or any specific surgical or medical complication included in this study. After 1:1 exact matching, the results of this study suggest that zero-profile (stand-alone) implants have similar outcomes compared to grafts with plating systems, with no observed differences in all-cause surgical or medical complications profile.

Cervical disc arthroplasty for magnetic resonance-evident cervical spondylotic myelopathy: comparison with anterior cervical discectomy and fusion.

Anterior cervical discectomy and fusion (ACDF) is a standard surgical approach for cervical spondylotic myelopathy (CSM) caused by disc herniations. Although cervical disc arthroplasty (CDA) has become, in the past decade, a viable alternative to ACDF in selected patients, the differences among patients with CSM treated with CDA and ACDF remain elusive. The effectiveness of motion preservation devices in CSM is also unclear. Adult patients who underwent 1- or 2-level CDA or ACDF between 2007 and 2021 were retrospectively reviewed. Patients whose preoperative T2-weighted MRI demonstrated increased intramedullary signal intensity (IISI) were included and analyzed for the following: comparison of the length of IISI on pre- and postoperative MR images as well as range of motion (ROM) at the indexed levels between the CDA and ACDF groups. Measurement for clinical outcomes included the visual analog scale (VAS) of the arm and neck, the Neck Disability Index, and modified Japanese Orthopaedic Association scores. Perioperative clinical data were also compared between the two groups. A total of 122 patients were allocated to the CDA group and 108 to the ACDF group, with mean follow-ups of 46.6 and 39.0 months, respectively. Patients in the CDA group were younger than those in the ACDF group (47.64 ± 12.40 vs 61.73 ± 12.25 years, p < 0.001) (mean ± SD). The ACDF group had more 2-level surgery compared to the CDA group (p = 0.002). Both groups had significant regression of IISI on postoperative MRI compared to that of preoperative imaging (CDA: 1.23 ± 0.84 to 0.28 ± 0.39 cm; ACDF: 1.07 ± 0.60 to 0.37 ± 0.42 cm; both p < 0.001). The decrease in the length of IISI was similar between the two groups (p = 0.058). The postoperative ROM was well preserved in the CDA group (superior to ACDF, which yielded minimal ROM postoperatively). Both the CDA and ACDF groups demonstrated improvement in Neck Disability Index and modified Japanese Orthopaedic Association scores at 24 months postoperatively. The CDA group had significant improvements on VAS scores, whereas the improvement did not reach significance for the ACDF group at 24 months postoperatively. Significant shortening of IISI on T2-weighted MRI was demonstrated after both CDA and ACDF. At 24 months postoperatively, all clinical outcomes demonstrated improvement after both strategies, except that the VAS score was not significantly improved for ACDF. Therefore, CDA is a safe and effective option for patients with MR-evident CSM.

Hybrid fixation versus conventional cage-plate construct in 3-level ACDF: Introduce the “seesaw theory” of stand-alone cage

Study designA retrospective study. BackgroundConventional cage-plate construct (CCP) was widely used in anterior cervical discectomy and fusion (ACDF), but the rigid fixation limits the motion of fused segments. Self-locking stand-alone cage (SSC) was an alternative for ACDF procedures and showed several superiorities. However, the effect of hybrid fixation in 3-level ACDF remains unknown. ObjectiveTo assess the clinical and radiological outcomes of hybrid fixation with SSC and CCP against conventional CCP in 3-level ACDF. MethodA retrospective review of patients who underwent 3-level ACDF at Renji Hospital between January 2018 and December 2019 was performed. Eighty-three patients met the inclusion and exclusion criteria and were stratified into 2 groups based on the fixation methods. The clinical outcomes, functional outcomes, and radiological parameters were collected and analyzed. ResultsNo significant difference was observed between the two groups in the mean age, sex, body mass index, hospital stay, and duration of follow-up. The postoperative C2–7 Cobb angle in the CCP group was significantly greater than that in the hybrid group. The rate of cervical proximal junctional kyphosis (CPJK) in the hybrid group was significantly lower than that in the CCP group. The CCP group suffered significantly higher rates of adjacent segment degeneration (ASD) than the hybrid group at 2 years postoperatively. Moreover, the incidence of postoperative dysphagia was lower in the hybrid group. No significant differences were observed in JOA and NDI scores between the two groups. ConclusionThe hybrid fixation achieved comparable clinical outcomes against CCP fixation, indicating that hybrid fixation is an alternative procedure in 3-level ACDF.

Comparison of Flexion Relaxation Phenomenon After Single-Level and Multi-Level Anterior Cervical Discectomy and Fusion

A prospective cohort study. This study aims to assess the influence of the number of fused segments on cervical paravertebral muscles by comparing the changes of the cervical flexion relaxation phenomenon (FRP) after single-level versus multi-level anterior cervical discectomy and fusion (ACDF). A total of 115 patients underwent ACDF were retrospectively recruited, and divided into 1-level group (n=44), 2-level group (n=40) and 3-4-level group (n=31). The flexion relaxation experiment was carried out 3 days preoperatively and 12 months postoperatively by surface electromyography (SEMG). Patients were examined by the neck Visual Analogue Scale (VAS), the cervical Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI) and C2-7 range of motion (ROM). There was a significant difference in the time-related changes of FRR among the three groups before and after surgery (F=85.701, P<0.001). 35 patients (79.55%) with 1 level ACDF and 11 patients (27.5%) with 2 levels ACDF had FRP restored to normal at 12 months postoperatively. However, only one patient (3.33%) had normalized FRP after 3-4 levels ACDF. There were significant differences in the time-related changes of the normalized SEMG RMS values in each phase before and after surgery (P=0.018, P<0.001, P<0.001, P<0.001). A significant correlation was found between the changes in C2-7ROM and FRR in three groups (P=0.007, 0.003 and 0.036). Single-level ACDF contributes to normalize the FRP of cervical paravertebral muscles, which, however, is not ideally recovered by 2-level ACDF. On the contrary, 3 or 4-level ACDF could not normalize the cervical FRP. Our research supported the passive structure hypothesis.

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

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. 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 12months, patient-reported postoperative pain, and any repeat surgeries. Univariate analysis was performed according to data normality and variables for PSM cohorts. 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). 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.

The Effect of Preoperative Exposure to Benzodiazepines on Opioid Consumption After One and Two-level Anterior Cervical Discectomy and Fusion.

Retrospective cohort. Investigate the relationship between preoperative benzodiazepine exposure and postoperative opioid use in patients undergoing primary 1 or 2-level anterior cervical discectomy and fusion (ACDF). Little is known about the effect of preoperative benzodiazepine exposure on postoperative opioid use in spine surgery. Patients undergoing primary 1 or 2-level ACDF at a single institution from February 2020 to November 2021 were identified through electronic medical records. The prescription drug monitoring program was utilized to record the name, dosage, and quantity of preoperative benzodiazepines/opioids filled within 60 days before surgery and postoperative opioids 6 months after surgery. Patients were classified as benzodiazepine naïve or exposed according to preoperative usage, and postoperative opioid dose and duration were compared between groups. Regression analysis was performed for outcomes that demonstrated statistical significance, adjusting for preoperative opioid use, age, sex, and body mass index. Sixty-seven patients comprised the benzodiazepine-exposed group whereas 90 comprised the benzodiazepine-naïve group. There was no significant difference in average daily morphine milligram equivalents between groups (median: 96.0 vs 65.0, P = 0.11). The benzodiazepine-exposed group received postoperative opioids for a longer duration (median: 32.0 d vs 12.0 d, P = 0.004) with more prescriptions (median: 2.0 vs 1.0, P = 0.004) and a greater number of pills (median: 110.0 vs 59.0, P = 0.007). On regression analysis, preoperative benzodiazepine use was not significantly associated with postoperative opioid duration [incidence rate ratio (IRR): 0.93, P = 0.74], number of prescriptions (IRR: 1.21, P = 0.16), or number of pills (IRR: 0.89, P = 0.58). While preoperative benzodiazepine users undergoing primary 1 or 2-level ACDF received postoperative opioids for a longer duration compared with a benzodiazepine naïve cohort, preoperative benzodiazepine use did not independently contribute to this observation. These findings provide insight into the relationship between preoperative benzodiazepine use and postoperative opioid consumption. Level III.

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

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. 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. 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 two groups differed significantly only in terms of age (p=.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=.004); however, significance was lost at 6-months (98.2% vs. 88.4%, respectively; p=.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=.02). 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.