Comparison of Outcomes Including or Excluding the Level of Listhesis After ACDF in the Setting of Degenerative Spondylolisthesis.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: The goal of this study is to evaluate the outcomes of patients with cervical degenerative spondylolisthesis (DS) undergoing anterior cervical discectomy and fusion (ACDF), specifically comparing surgeries that include versus exclude the DS level. SUMMARY OF BACKGROUND DATA: DS has been extensively studied in the lumbar spine associated with both back and leg pain leading to worse patient quality of life measures. Conversely, there is a relative dearth of literature regarding surgical and clinical outcomes in the setting of cervical DS. MATERIALS AND METHODS: A total of 315 patients undergoing ACDF between 2014 and 2018 with minimum of 1-year postoperative patient-reported outcome measures (PROMs) were retrospectively reviewed. Forty-six patients were found to have DS and were categorized based on whether an ACDF was performed at the same level (SL) or at a different level (DL) than the spondylolisthesis. Patient demographics, surgical parameters, preoperative and postoperative radiographs, and PROMs were compared between groups. RESULTS: Of the 315 patients, a total of 46 met the inclusion criteria including 21 SL and 25 DL patients. There were no significant differences in patient demographics between the groups. The SL cohort had a significantly worse preoperative sagittal vertical axis (SL: 34.4 vs. 26.1, P=0.025) but no difference in postoperative or delta sagittal vertical axis. Both patient cohorts reported significant postoperative improvement in all PROMs, except Short-Form 12 Mental Component Score in the SL group. There were no differences between the groups regarding Visual Analog Scale Neck, Visual Analog Scale Arm, Neck Disability Index, or Short-Form 12 Physical Component Score. Regression analysis demonstrated SL to be a significant negative predictor for improvement in Short-Form 12 Mental Component Score (ß: -11.27, P=0.10). CONCLUSION: Patients treated only at their neurologically symptomatic levels, excluding asymptomatic listhesis in their construct, can expect equivalent radiographic as well as physical function, disability, and pain outcomes 1 year after ACDF compared with patients whose listhetic level was included in their construct. LEVEL OF EVIDENCE: Level III.

Patients With Preoperative Cervical Deformity Experience Similar Clinical Outcomes to Those Without Deformity Following 1-3 Level Anterior Cervical Decompression and Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim was to compare the outcomes of patients with incompletely corrected cervical deformity against those without deformity following short-segment anterior cervical decompression and fusion for clinically significant radiculopathy or myelopathy. SUMMARY OF BACKGROUND DATA: Cervical deformity has increasingly been recognized as a driver of disability and has been linked to worse patient-reported outcomes measures (PROMs) after surgery. METHODS: Patients 18 years or above who underwent 1-3 level anterior cervical decompression and fusion to address radiculopathy and/or myelopathy at a single institution between 2014 and 2018 with at least 1 year of PROMs were reviewed. Patients were categorized based on cervical deformity into 2 groups: sagittal vertebral axis (cSVA) ≥40 mm as the deformity group, and cSVA <40 mm as the nondeformity group. Patient demographics, surgical parameters, preoperative and postoperative radiographs, and minimum 1-year PROMs were compared. RESULTS: Of the 230 patients, 191 (83%) were in the nondeformity group and 39 (17%) in the deformity group. Patients with deformity were more likely to be male (69.2% vs. 40.3%, P<0.001) and have a greater body mass index (32.8 vs. 29.7, P=0.028). The deformity group had significantly greater postoperative cSVA (44.2 vs. 25.1 mm, P<0.001) but also had significantly greater ∆cSVA (-4.87 vs. 0.25 mm, P=0.007) than the nondeformity group. Both groups had significant improvements in visual analog scale arm, visual analog scale neck, Short-Form 12 Physical Component Score, and neck disability index (NDI) (P<0.001). However, the deformity group experienced significantly greater ∆NDI and ∆mental component score (MCS)-12 scores (-19.45 vs. -11.11, P=0.027 and 7.68 vs. 1.32, P=0.009). CONCLUSIONS: Patients with preoperative cervical sagittal deformity experienced relatively greater improvements in NDI and MCS-12 scores than those without preoperative deformity. These results suggest that complete correction of sagittal alignment is not required for patients to achieve significant clinical improvement. LEVEL OF EVIDENCE: III.

Cervical Alignment and Proximal and Distal Junctional Failure in Posterior Cervical Fusion: A Multicenter Comparison of 2 Surgical Approaches.

STUDY DESIGN: This was a multicenter retrospective cohort study. OBJECTIVE: The purpose of this study was to compare the surgical and radiographic outcomes of patients undergoing posterior cervical fusion (PCF) with constructs extending from C2 to T2 to patients with constructs extending from C3 to T1. SUMMARY OF BACKGROUND DATA: Limited evidence exists regarding the appropriate level of proximal and distal extension of PCF constructs. METHODS: A multicenter retrospective cohort study of patients who underwent PCF between 2012 and 2020 was performed. Surgical and radiographic outcomes were compared between those who had C3-T1 or C2-T2 constructs. RESULTS: A total of 155 patients were included in the study (C2-T2: 106 patients, C3-T1: 49 patients). There were no significant differences in demographics or preoperative symptoms between cohorts. Fusion rates were significantly higher in the C2-T2 (93%) than the C3-T1 (80%, P=0.040) cohort. When comparing the C2-T2 to the C3-T1 cohort, the C3-T1 cohort had a significantly greater rate of proximal junctional failure (2% vs. 10%, P=0.006), distal junctional failure (1% vs. 20%, P<0.001) and distal screw loosening (4% vs. 15%, P=0.02). Although ∆C2-C7 sagittal vertical axis increased significantly in both cohorts (C2-T2: 6.2 mm, P=0.04; C3-T1: 8.4 mm, P<0.001), correction did not significantly differ between groups (P=0.32). The C3-T1 cohort had a significantly greater increase in ∆C2 slope (8.0 vs. 3.1 degrees, P=0.03) and ∆C0-C2 Cobb angle (6.4 vs. 1.2 degrees, P=0.04). CONCLUSION: In patients undergoing PCF, a C2-T2 construct demonstrated lower rates of pseudarthrosis, distal junctional failure, proximal junctional failure, and compensatory upper cervical hyperextension compared with a C3-T1 construct.