Does operative level impact dysphagia severity following anterior cervical discectomy and fusion? a multicenter prospective analysis.

STUDY DESIGN: Prospective multi-center cohort study. OBJECTIVE: To explore the association between operative level and postoperative dysphagia after anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Dysphagia is common following ACDF and has several risk factors including soft tissue edema. The degree of prevertebral soft tissue edema varies based upon the operative cervical level. However, the operative level has not been evaluated as a source of postoperative dysphagia. METHODS: Adult patients undergoing elective ACDF were prospectively enrolled at three academic centers. Dysphagia was assessed using the Bazaz questionnaire, Dysphagia Short Questionnaire (DSQ), and Eating Assessment Tool-10 (EAT-10) preoperatively and at 2, 6, 12, and 24-weeks postoperatively. Patients were grouped based on inclusion of specific surgical levels in the fusion construct. Multivariable regression analyses were performed evaluating the independent effects of number of surgical levels and inclusion of each particular level on dysphagia symptoms. RESULTS: A total of 130 patients were included. Overall, 24 (18.5%) patients had persistent postoperative dysphagia at 24 weeks and were older, female, and less likely to be drink alcohol. There was no difference in operative duration or dexamethasone administration. Patients with persistent dysphagia were significantly more likely to have C4-C5 included in the fusion construct (62.5% vs. 34.9%, P=0.024) but there were no differences based on inclusion of other levels. On multivariable regression, inclusion of C3-C4 or C6-C7 were associated with more severe EAT-10 (ß:9.56, P=0.016 and ß:8.15, P=0.040) and DSQ (ß:4.44, P=0.023 and (ß:4.27, P=0.030) at 6 weeks. At 12-weeks, C3-C4 fusion was also independently associated with more severe dysphagia (EAT-10 ß:4.74, P=0.024). CONCLUSION: The location of prevertebral soft tissue swelling may impact the duration and severity of patient-reported dysphagia outcomes at up to 24 weeks postoperatively. In particular, inclusion of C3-C4 and C4-C5 into the fusion may be associated with dysphagia severity.

Significance of Facet Fluid Index in Anterior Cervical Degenerative Spondylolisthesis.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To correlate cervical facet fluid characteristics to radiographic spondylolisthesis, determine if facet fluid is associated with instability in cervical degenerative spondylolisthesis, and examine whether vertebral levels with certain facet fluid characteristics and spondylolisthesis are more likely to be operated on. OVERVIEW OF LITERATURE: The relationship between facet fluid and lumbar spondylolisthesis is well-documented; however, there is a paucity of literature investigating facet fluid in degenerative cervical spondylolisthesis. METHODS: Patients diagnosed with cervical degenerative spondylolisthesis were identified from a hospital's medical records. Demographic and surgical characteristics were collected through a structured query language search and manual chart review. Radiographic measurements were made on preoperative MRIs for all vertebral levels diagnosed with spondylolisthesis and adjacent undiagnosed levels between C3 and C6. The facet fluid index was calculated by dividing the facet fluid measurement by the width of the facet. Bivariate analysis was conducted to compare facet characteristics based on radiographic spondylolisthesis and spondylolisthesis stability. RESULTS: We included 154 patients, for whom 149 levels were classified as having spondylolisthesis and 206 levels did not. The average facet fluid index was significantly higher in patients with spondylolisthesis (0.26±0.07 vs. 0.23±0.08, p <0.001). In addition, both fluid width and facet width were significantly larger in patients with spondylolisthesis (p <0.001 each). Cervical levels in the fusion construct demonstrated a greater facet fluid index and were more likely to have unstable spondylolisthesis than stable spondylolisthesis (p <0.001 each). CONCLUSIONS: Facet fluid index is associated with cervical spondylolisthesis and an increased facet size and fluid width are associated with unstable spondylolisthesis. While cervical spondylolisthesis continues to be an inconclusive finding, vertebral levels with spondylolisthesis, especially the unstable ones, were more likely to be included in the fusion procedure than those without spondylolisthesis.

Correction of Spinal Sagittal Alignment after Posterior Lumbar Decompression: Does Severity of Central Canal Stenosis Matter?

STUDY DESIGN: This study adopted a retrospective study design. PURPOSE: Our study aimed to investigate the impact of central canal stenosis severity on surgical outcomes and lumbar sagittal correction after lumbar decompression. OVERVIEW OF LITERATURE: Studies have evaluated sagittal correction in patients with central canal stenosis after lumbar decompression and the association of stenosis severity with worse preoperative sagittal alignment. However, none have evaluated the impact of spinal stenosis severity on sagittal correction. METHODS: Patients undergoing posterior lumbar decompression (PLD) of ≤4 levels were divided into severe and non-severe central canal stenosis groups based on the Lee magnetic resonance imaging (MRI) grading system. Patients without preoperative MRI or inadequate visualization on radiographs were excluded. Surgical characteristics, clinical outcomes, and sagittal measurements were compared. Multivariate logistic regression was performed to determine the predictors of pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), and pelvic incidence minus lumbar lordosis (PI-LL). RESULTS: Of the 142 patients included, 39 had severe stenosis, and 103 had non-severe stenosis. The mean follow-up duration for the cohort was 4.72 months. Patients with severe stenosis were older, had higher comorbidity indices and levels decompressed, and longer lengths of stay and operative times (p <0.001). Although those with severe stenosis had lower lordosis, lower SS, and higher PI-LL mismatch preoperatively, no differences in Delta LL, SS, PT, or PI-LL were observed between the two groups (p >0.05). On multivariate regression, severe stenosis was a significant predictor of a lower preoperative LL (estimate=-5.243, p =0.045) and a higher preoperative PI-LL mismatch (estimate=6.192, p =0.039). No differences in surgical or clinical outcomes were observed (p >0.05). CONCLUSION: Severe central lumbar stenosis was associated with greater spinopelvic mismatch preoperatively. Sagittal balance improved in both patients with severe and non-severe stenosis after PLD to a similar degree, with differences in sagittal parameters remaining after surgery. We also found no differences in postoperative outcomes associated with stenosis severity.

Reimbursement of Lumbar Fusion at an Orthopaedic Specialty Hospital Versus Tertiary Referral Center.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: To explore the differences in Medicare reimbursement for lumbar fusion performed at an orthopaedic specialty hospital (OSH) and a tertiary referral center and to elucidate drivers of Medicare reimbursement differences. SUMMARY OF BACKGROUND DATA: To provide more cost-efficient care, appropriately selected patients are increasingly being transitioned to OSHs for lumbar fusion procedures. There are no studies directly comparing reimbursement of lumbar fusion between tertiary referral centers (TRC) and OSHs. METHODS: Reimbursement data for a tertiary referral center and an orthopaedic specialty hospital were compiled through the Centers for Medicare and Medicaid Services. Any patient with lumbar fusions between January 2014 and December 2018 were identified. OSH patients were matched to TRC patients by demographic and surgical variables. Outcomes analyzed were reimbursement data, procedure data, 90-day complications and readmissions, operating room times, and length of stay (LOS). RESULTS: A total of 114 patients were included in the final cohort. The tertiary referral center had higher post-trigger ($13,554 vs. $8,541, P<0.001) and total episode ($49,973 vs. $43,512, P<0.010) reimbursements. Lumbar fusion performed at an OSH was predictive of shorter OR time (ß=0.77, P<0.001), shorter procedure time (ß=0.71, P<0.001), and shorter LOS (ß=0.53, P<0.001). There were no significant differences in complications (9.21% vs. 15.8%, P=0.353) or readmission rates (3.95% vs. 7.89%, P=0.374) between the 2 hospitals; however, our study is underpowered for complications and readmissions. CONCLUSION: Lumbar fusion performed at an OSH, compared with a tertiary referral center, is associated with significant Medicare cost savings, shorter perioperative times, decreased LOS, and decreased utilization of post-acute resources. LEVEL OF EVIDENCE: 3.

How Does the Severity of Neuroforaminal Compression in Cervical Radiculopathy Affect Outcomes of Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: This study is a retrospective cohort study. PURPOSE: This study aims to determine whether preoperative neuroforaminal stenosis (FS) severity is associated with motor function patient-reported outcome measures (PROMs) following anterior cervical discectomy and fusion (ACDF). OVERVIEW OF LITERATURE: Cervical FS can significantly contribute to patient symptoms. While magnetic resonance imaging (MRI) has been used to classify FS, there has been limited research into the impact of FS severity on patient outcomes. METHODS: Patients undergoing primary, elective 1-3 level ACDF for radiculopathy at a single academic center between 2015 and 2021 were identified retrospectively. Cervical FS was evaluated using axial T2-weighted MRI images via a validated grading scale. The maximum degree of stenosis was used for multilevel disease. Motor symptoms were classified using encounters at their final preoperative and first postoperative visits, with examinations ≤3/5 indicating weakness. PROMs were obtained preoperatively and at 1-year follow-up. Bivariate analysis was used to compare outcomes based on stenosis severity, followed by multivariable analysis. RESULTS: This study included 354 patients, 157 with moderate stenosis and 197 with severe stenosis. Overall, 58 patients (16.4%) presented with upper extremity weakness ≤3/5. A similar number of patients in both groups presented with baseline motor weakness (13.5% vs. 16.55, p =0.431). Postoperatively, 97.1% and 87.0% of patients with severe and moderate FS, respectively, experienced full motor recovery (p =0.134). At 1-year, patients with severe neuroforaminal stenosis presented with significantly worse 12-item Short Form Survey Physical Component Score (PCS-12) (33.3 vs. 37.3, p =0.049) but demonstrated a greater magnitude of improvement (Δ PCS-12: 5.43 vs. 0.87, p =0.048). Worse stenosis was independently associated with greater ΔPCS-12 at 1-year (ß =5.59, p =0.022). CONCLUSIONS: Patients with severe FS presented with worse preoperative physical health. While ACDF improved outcomes and conferred similar motor recovery in all patients, those with severe FS reported much better improvement in physical function.

Radiographic and Patient-Reported Outcomes: Anteriorly Placed Transforaminal Lumbar Interbody Fusion Cage vs. Anterior Lumbar Interbody Fusion with Posterior Instrumentation.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: To compare outcomes in anteriorly placed transforaminal lumbar interbody fusions (TLIFs) and anterior lumbar interbody fusions (ALIFs). SUMMARY OF BACKGROUND DATA: TLIF and ALIF are surgical techniques that have become more prevalent in recent years. Although studies have compared the two, none have considered TLIFs with anteriorly placed cages, which may serve as a better comparison to ALIFs. MATERIALS AND METHODS: Patients undergoing TLIF or ALIF with posterior instrumentation from 2010-2020 at a tertiary care institution were retrospectively identified. TLIF cage position was assessed and those with anterior placement were included. Electronic medical records were reviewed to identify patient characteristics and patient-reported outcomes. Radiographic outcomes included posterior disc height (DH), lumbar lordosis (LL), sacral slope (SS), pelvic incidence (PI) and pelvic tilt (PT). Statistical analysis was performed to compare the two groups. RESULTS: Of the 351 patients, 108 had ALIF with posterior instrumentation and 207 had a TLIF. Preoperatively, TLIF patients had less LL (53.7° vs. 60.6°, P<0.001), SS (38.3° vs. 43.7°, P<0.001), and PI (60.1° vs. 66.1°, P<0.001), all of which remained significant at one-year and long-term follow-up (P<0.001). The TLIF group had less ∆DH (1.51° vs. 5.43°, P<0.001), ∆LL (1.8° vs. 2.97°, P=0.038), and ∆SL (0.18° vs. 4.40°, P<0.001) at one year postoperatively. At two to three years, ∆DH (P<0.001) and ∆SL (P=0.001) remained significant, but ∆LL (P=0.695) did not. Patients in the TLIF group had higher VAS-Back scores one year postoperatively (3.68 vs. 2.16, P=0.008) and experienced less improvement in ODI (-17.1 vs. -28.6, P=0.012) and VAS-Back (-2.67 vs. -4.50, P=0.008) compared to ALIF patients. CONCLUSIONS: Our findings suggest that ALIF with posterior instrumentation performed superiorly in radiographic outcomes and PROMs compared to anteriorly placed TLIFs. Anteriorly placed TLIF cages may not achieve the same results as those of ALIF cages.

Evaluating Dysphagia Duration and Severity After ACDF in Patients With Underlying Dysphagia - A Prospective, Multicenter Study.

STUDY DESIGN: Prospective Cohort Study. OBJECTIVES: The purpose of this study was to prospectively evaluate the impact of preoperative dysphagia on the postoperative incidence and severity of dysphagia in patients undergoing ACDF at multiple institutions. METHODS: After IRB approval, patients over 18 years of age who underwent an elective ACDF for degenerative conditions were prospectively enrolled at two academic centers from 2018 to 2021. Preoperative dysphagia was self-reported by patients through a pre-operative questionnaire on a binary basis. Patients completed dysphagia surveys (Bazaz, Dysphagia Short Questionnaire, 10-item Eating Assessment Tool) to assess dysphagia severity during their preoperative visit, and these dysphagia surveys were repeated immediately postoperatively, at two weeks and again at six, 12, and 24 weeks postoperatively. Patients were stratified into three subgroups based on dysphagia status preoperatively and immediately postoperatively and compared using ANOVA tests or Kruskal-Wallis tests for continuous variables and Pearson chi-square analysis or Fisher's Exact test for categorical variables. RESULTS: A total of 168 patients (23 with preoperative dysphagia, 145 without preoperative dysphagia) met study criteria and were enrolled in the study. Patients with preoperative dysphagia had less frequent alcohol consumption (23.8% vs 53.7%, P = .0210), and higher rates of dysphagia at 2-weeks (77.8% vs 38.7%, P = .004) and 24-weeks (43.8% vs 14.8%, P = .010) postoperatively. These patients also had higher severity scores for dysphagia on the Bazaz (P = .001), DSQ (P = .012), EAT10 (P = .022) questionnaires at the 2-week follow-up period, higher DSQ scores (P = .036) at the 6-week follow-up period, higher EAT-10 scores (P = .009) at the 12-week follow-up period, and higher Bazaz (P = .001), DSQ (P = .002), and EAT-10 (P = .005) scores at the 24-week follow-up period. There were no differences in demographic, medical history, surgical variables, rates of ENT consultation, length of stay, or other in-hospital events between groups. CONCLUSIONS: Patients undergoing ACDF who had preoperative dysphagia have prolonged postoperative dysphagia and greater dysphagia severity. Surgeons should be aware of the risk of prolonged dysphagia severity that may persist past 24 weeks after surgery when discussing clinical decisions with patients.

Comparison of Postoperative Opioid Use After Anterior Cervical Diskectomy and Fusion or Posterior Cervical Fusion.

INTRODUCTION: Posterior cervical fusion (PCF) and anterior cervical diskectomy and fusion (ACDF) are two main surgical management options for the treatment of cervical spondylotic myelopathy. Although ACDF is less invasive than PCF which should theoretically reduce postoperative pain, it is still unknown whether this leads to reduced opioid use. Our objective was to evaluate whether PCF increases postoperative opioid use compared with ACDF. METHODS: We retrospectively identified all patients undergoing 2-level to 4-level ACDF or PCF at a single center from 2017 to 2021. Our state's prescription drug-monitoring program was queried for filled opioid prescriptions using milligrams morphine equivalents (MMEs) up to 1 year postoperatively. In-hospital opioid use was collected from the electronic medical record. Bivariate statistics compared ACDF and PCF cohorts. Multivariate linear regression was done to assess independent predictors of in-hospital opioid use and short-term (0 to 30 days), subacute (30 to 90 days), and long-term (3 to 12 months) opioid prescriptions. RESULTS: We included 211 ACDF patients and 91 PCF patients. Patients undergoing PCF used more opioids during admission (126.7 vs. 51.0 MME, P < 0.001) and refilled more MMEs in the short-term (118.2 vs. 86.1, P = 0.001) but not subacute (33.6 vs. 19.7, P = 0.174) or long-term (85.6 vs. 47.8, P = 0.310) period. A similar percent of patients in both groups refilled at least one prescription after 90 days (39.6% vs. 33.2%, P = 0.287). PCF (ß = 56.7, P = 0.001) and 30-day preoperative MMEs (ß = 0.28, P = 0.041) were associated with greater in-hospital opioid requirements. PCF (ß = 26.7, P = 0.039), C5 nerve root irritation (ß = 51.4, P = 0.019), and a history of depression (ß = 40.9, P < 0.001) were independently associated with 30-day postoperative MMEs. CONCLUSIONS: PCF is initially more painful than ACDF but does not lead to persistent opioid use. Surgeons should optimize multimodal analgesia protocols to reduce long-term narcotic usage rather than change the surgical approach.Level of Evidence:III.

A Comparison of Radiographic Alignment between Bilateral and Unilateral Interbody Cages in Patients Undergoing Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To compare radiographic outcomes between unilateral and bilateral cage placement in transforaminal lumbar interbody fusions (TLIF) and to determine if the rate of fusion at the 1-year postoperative point was different in patients who received bilateral versus unilateral cages. OVERVIEW OF LITERATURE: There is no clear evidence to dictate whether bilateral or unilateral cages promote superior radiographic or surgical outcomes in TLIF. METHODS: Patients >18 years old who underwent primary one- or two-level TLIFs at our institution were identified and propensitymatched in a 3:1 fashion (unilateral:bilateral). Patient demographics, surgical characteristics, and radiographic outcomes, including vertebral endplate obliquity, segmental lordosis, subsidence, and fusion status, were compared between groups. RESULTS: Of the 184 patients included, 46 received bilateral cages. Bilateral cage placement was associated with greater subsidence (1.06±1.25 mm vs. 0.59±1.16 mm, p=0.028) and enhanced restoration of segmental lordosis (5.74°±14.1° vs. -1.57°±10.9°, p=0.002) at the 1-year postoperative point, while unilateral cage placement was associated with an increased correction of endplate obliquity (-2.02°±4.42° vs. 0.24°±2.81°, p<0.001). Bilateral cage placement was significantly associated with radiographic fusion on bivariate analysis (89.1% vs. 70.3%, p=0.018) and significantly predicted radiographic fusion on multivariable regression analysis (estimate, 1.35; odds ratio, 3.87; 95% confidence interval, 1.51-12.05; p=0.010). CONCLUSIONS: Bilateral interbody cage placement in TLIF procedures was associated with restoration of lumbar lordosis and increased fusion rates. However, endplate obliquity correction was significantly greater for patients who received a unilateral cage.

Comparing Posterior Lumbar Decompression and Fusion and Transforaminal Lumbar Interbody Fusion in Lumbar Degenerative Spondylolisthesis as Assessed by the CARDS Classification System.

OBJECTIVE: In a retrospective cohort study, we compared the outcomes among clinical and radiographic degenerative spondylolisthesis (CARDS) subtypes for patients undergoing posterior lumbar decompression and fusion (PLDF) or transforaminal lumbar interbody fusion (TLIF) and evaluated the CARDS system as a tool to guide clinical decisions regarding the treatment of degenerative spondylolisthesis (DS). METHODS: Patients undergoing PLDF or TLIF for DS from 2010 to 2020 were identified. The patients were grouped by the preoperative CARDS classification. Multivariate analysis was used to determine the effects of the treatment approach on the 1-year patient-reported outcome measures (PROMs) and 90-day surgical outcomes. RESULTS: A total of 1056 patients were included: 148 patients with type A DS, 323 with type B, 525 with type C, and 60 with type D. Patients with CARDS types A and C who underwent PLDF experienced a longer length of stay and were less likely to be discharged home. No differences were found in the incidence of revisions, complications, or readmissions between the surgical approaches. Patients with CARDS type A undergoing PLDF were less likely to achieve a minimal clinically important difference for back pain (36.8% vs. 76.7%; P = 0.013). No other significant differences were found in the PROMs among the CARDS subtypes. TLIF independently predicted for better leg pain improvement using the visual analog scale at 1 year of follow-up (ß = -2.92; P = 0.017) for patients with CARDS type A. Multivariable analysis demonstrated no significant differences in PROMs by surgical approach among the other CARDS subtypes. CONCLUSIONS: Patients with disc space collapse and endplate apposition (CARDS type A) appear to benefit from TLIF. However, patients with lumbar spondylolisthesis without disc space collapse or kyphotic angulation (CARDS types B and C) showed no benefit from additional interbody placement.

Effect of Clinical and Radiographic Degenerative Spondylolisthesis Classification on Patient-reported Outcomes and Spinopelvic Parameters for Patients With Single-level L4-L5 Degenerative Spondylolisthesis After Lumbar Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To determine whether preoperative clinical and radiographic degenerative spondylolisthesis (CARDS) classification is associated with differences in patient-reported outcomes and spinopelvic parameters after posterior decompression and fusion for L4-L5 degenerative spondylolisthesis (DS). SUMMARY: The CARDS classification for lumbar DS, an alternative to the Meyerding system, considers additional radiographic findings such as disc space collapse and segmental kyphosis and stratifies DS into 4 radiographically distinct classes. Although CARDS has been shown to be a reliable and reproducible method for classifying DS, very few studies have assessed whether the CARDS types represent distinct clinical entities. PATIENTS AND METHODS: A retrospective cohort analysis was conducted on patients with L4-L5 DS who underwent posterior lumbar decompression and fusion. Changes in spinopelvic alignment and patient-reported outcomes measures, including recovery ratios and percentage of patients achieving the minimal clinically important difference, were compared among patients in each CARDS classification 1-year postoperatively using analysis of variance or Kruskal-Wallis H with Dunn post hoc analysis. Multiple linear regression determined whether CARDS groups significantly predicted patient-reported outcomes measures, lumbar lordosis (LL), and pelvic incidence-lumbar lordosis mismatch (PI-LL) while controlling for demographic and surgical characteristics. RESULTS: Preoperative type B spondylolisthesis predicted decreased improvement in "physical component and mental component score of the short form-12" compared with type A spondylolisthesis (ß-coefficient = -5.96, P = 0.031) at 1 year. Significant differences were found between CARDS groups with regards to ΔLL (A: -1.63 degrees vs B: -1.17 degrees vs C: 2.88 degrees vs D: 3.19 degrees, P = 0.010) and ΔPI-LL (A: 1.02 degrees vs B: 2.09 degrees vs C: -2.59 degrees vs D: -3.70 degrees, P = 0.012). Preoperative type C spondylolisthesis was found to predict increased LL (ß-coefficient = 4.46, P = 0.0054) and decreased PI-LL (ß-coefficient = -3.49, P = 0.025) at 1 year compared with type A spondylolisthesis. CONCLUSIONS: Clinical and radiographic outcomes differed significantly by preoperative CARDS classification type for patients undergoing posterior decompression and fusion for L4-L5 DS. LEVEL OF EVIDENCE: Level III.

Patient-specific Risk Factors Increase Episode of Care Costs After Lumbar Decompression.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To determine, which patient-specific risk factors increase total episode of care (EOC) costs in a population of Centers for Medicare and Medicaid Services beneficiaries undergoing lumbar decompression. SUMMARY OF BACKGROUND DATA: Lumbar decompression is an effective option for the treatment of central canal stenosis or radiculopathy in patients unresponsive to nonoperative management. Given that elderly Americans are more likely to have one or more chronic medical conditions, there is a need to determine, which, if any, patient-specific risk factors increase health care costs after lumbar decompression. METHODS: Care episodes limited to lumbar decompression surgeries were retrospectively reviewed on a Centers for Medicare and Medicaid Service reimbursement database at our academic institution between 2014 and 2019. The 90-day total EOC reimbursement payments were collected. Patient electronic medical records were then matched to the selected care episodes for the collection of patient demographics, medical comorbidities, surgical characteristics, and clinical outcomes. A stepwise multivariate linear regression model was developed to predict patient-specific risk factors that increased total EOC costs after lumbar decompression. Significance was set at P <0.05. RESULTS: A total of 226 patients were included for analysis. Risk factors associated with increased total EOC cost included increased age (per year) (ß = $324.70, P < 0.001), comorbid depression (ß = $4368.30, P = 0.037), revision procedures (ß = $6538.43, P =0.012), increased hospital length of stay (per day) (ß = $2995.43, P < 0.001), discharge to an inpatient rehabilitation facility (ß = $14,417.42, P = 0.001), incidence of a complication (ß = $8178.07, P < 0.001), and readmission (ß = $18,734.24, P < 0.001) within 90 days. CONCLUSIONS: Increased age, comorbid depression, revision decompression procedures, increased hospital length of stay, discharge to an inpatient rehabilitation facility, and incidence of a complication and readmission within 90 days were all associated with increased total episodes of care costs.

Facet Distraction and Dysphagia: A Prospective Evaluation of This Common Postoperative Issue Following Anterior Cervical Spine Surgery.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: Our primary study was to investigate whether the degree of postoperative facet and disk space distraction following anterior cervical discectomy and fusion (ACDF) affects the rate of postoperative dysphagia. SUMMARY OF BACKGROUND DATA: Although ACDF is safe and well tolerated, postoperative dysphagia remains a common complication. Intervertebral disk space distraction is necessary in ACDF to visualize the operative field, prepare the endplates for fusion, and facilitate graft insertion. However, the degree of distraction tolerated, before onset of dysphagia, is not well characterized ACDF. MATERIALS AND METHODS: A prospective cohort study was conducted of 70 patients who underwent ACDF between June 2018 and January 2019. Two independent reviewers measured all preoperative and postoperative radiographs measured for interfacet distraction distance and intervertebral distraction distance, with intrareviewer reproducibility measurements after one month. For multilevel surgery, the level with the greatest distraction was measured. Primary outcomes were numerical dysphagia (0-10), Eating Assessment Tool 10, and Dysphagia Symptom Questionnaire score collected at initial visit and two, six, 12, and 24 weeks postoperatively. RESULTS: A total of 70 patients were prospectively enrolled, 59 of whom had adequate radiographs. An average of 1.71 (SD: 0.70) levels were included in the ACDF construct. Preoperatively, 13.4% of patients reported symptoms of dysphagia, which subsequently increased in the postoperative period at through 12 weeks postoperatively, before returning to baseline at 24 weeks. Intrareviewer and interreviewer reliability analysis demonstrated strong agreement. There was no relationship between interfacet distraction distance/intervertebral distraction distance and dysphagia prevalence, numerical rating, Eating Assessment Tool 10, or Dysphagia Symptom Questionnaire. CONCLUSIONS: Patients who had an ACDF have an increased risk of dysphagia in the short term, however, this resolved without intervention by six months. Our data suggests increased facet and intervertebral disk distraction does not influence postoperative dysphagia rates. LEVEL OF EVIDENCE: 3.

The impact of cage positioning on lumbar lordosis and disc space restoration following minimally invasive lateral lumbar interbody fusion.

OBJECTIVE: The objective of this study was to evaluate patient and surgical factors that predict increased overall lumbar lordosis (LL) and segmental lordosis correction following a minimally invasive lateral lumbar interbody fusion (LLIF) procedure. METHODS: A retrospective review was conducted of all patients who underwent one- or two-level LLIF. Preoperative, initial postoperative, and 6-month postoperative measurements of LL, segmental lordosis, anterior disc height, and posterior disc height were collected from standing lateral radiographs for each patient. Cage placement was measured utilizing the center point ratio (CPR) on immediate postoperative radiographs. Spearman correlations were used to assess associations between cage lordosis and radiographic parameters. Multivariate linear regression was performed to assess independent predictors of outcomes. RESULTS: A total of 106 levels in 78 unique patients were included. Most procedures involved fusion of one level (n = 50, 64.1%), most commonly L3-4 (46.2%). Despite no differences in baseline segmental lordosis, patients with anteriorly or centrally placed cages experienced the greatest segmental lordosis correction immediately (mean anterior 4.81° and central 4.46° vs posterior 2.47°, p = 0.0315) and at 6 months postoperatively, and patients with anteriorly placed cages had greater overall lordosis correction postoperatively (mean 6.30°, p = 0.0338). At the 6-month follow-up, patients with anteriorly placed cages experienced the greatest increase in anterior disc height (mean anterior 6.24 mm vs posterior 3.69 mm, p = 0.0122). Cages placed more posteriorly increased the change in posterior disc height postoperatively (mean posterior 4.91 mm vs anterior 1.80 mm, p = 0.0001) and at 6 months (mean posterior 4.18 mm vs anterior 2.06 mm, p = 0.0255). There were no correlations between cage lordotic angle and outcomes. On multivariate regression, anterior cage placement predicted greater 6-month improvement in segmental lordosis, while posterior placement predicted greater 6-month improvement in posterior disc height. Percutaneous screw placement, cage lordotic angle, and cage height did not independently predict any radiographic outcomes. CONCLUSIONS: LLIF procedures reliably improve LL and increase intervertebral disc space. Anterior cage placement improves the lordosis angle greater than posterior placement, which better corrects sagittal alignment, but there is still a significant improvement in lordosis even with a posteriorly placed cage. Posterior cage placement provides greater restoration in posterior disc space height, maximizing indirect decompression, but even the anteriorly placed cages provided indirect decompression. Cage parameters including cage height, lordosis angle, and material do not impact radiographic improvement.

Effect of Drain Duration and Output on Perioperative Outcomes and Readmissions after Lumbar Spine Surgery.

STUDY DESIGN: Single-center retrospective cohort. PURPOSE: To compare surgical outcomes of patients based on lumbar drain variables relating to output and duration. OVERVIEW OF LITERATURE: The use of drains following lumbar spine surgery, specifically with respect to hospital readmission, postoperative hematoma, postoperative anemia, and surgical site infections, has been controversial. METHODS: Patients aged ≥18 years who underwent lumbar fusion with a postoperative drain between 2017 and 2020 were included and grouped based on hospital readmission status, last 8-hour drain output (<40 mL cutoff), or drain duration (2 days cutoff). Total output of all drains, total output of the primary drain, drain duration in days, drain output per day, last 8-hour output, penultimate 8-hour output, and last 8-hour delta (last 8-hour output subtracted by penultimate 8-hour output) were collected. Continuous and categorical data were compared between groups. Multivariate logistic regression analysis and receiver operating characteristic (ROC) analysis were performed to determine whether drain variables can predict hospital readmission, postoperative blood transfusions, and postoperative anemia. Alpha was 0.05. RESULTS: Our cohort consisted of 1,166 patients with 111 (9.5%) hospital readmissions. Results of regression analysis did not identify any of the drain variables as independent predictors of hospital readmission, postoperative blood transfusion, or postoperative anemia. ROC analysis demonstrated the drain variables to be poor predictors of hospital readmission, with the highest area under curve of 0.524 (drain duration), corresponding to a sensitivity of 61.3% and specificity of 49.9%. CONCLUSIONS: Drain output or duration did not affect readmission rates following lumbar spine surgery.

Serotonin Reuptake Inhibitor Increases Pseudarthrosis Rates in Anterior Cervical Discectomy and Fusions.

STUDY DESIGN: Retrospective cohort. PURPOSE: To determine (1) the effects of serotonin reuptake inhibitors in pseudarthrosis rates after anterior cervical decompression and fusion (ACDF) and (2) to identify patient-reported outcome measures in patients taking serotonin reuptake inhibitors. OVERVIEW OF LITERATURE: Recent literature suggests that selective serotonin reuptake inhibitors (SSRIs) may inhibit fracture healing via downregulation of osteoblast differentiation. Spinal fusion supplementation with osteoblast-rich substances enhances spinal fusion, thus SSRIs may be detrimental. METHODS: Patients with 1-year postoperative dynamic cervical spine radiographs following ACDF were grouped into serotonin reuptake inhibitor prescriptions (SSRI, serotonin-norepinephrine reuptake inhibitor [SNRI], or tricyclic antidepressant [TCA]) and no prescription (atypical antidepressant or no antidepressant). Pseudarthrosis was defined as ≥1 mm interspinous process motion on dynamic radiographs. Logistic regression models were controlled for confounding to analyze pseudarthrosis rates. Alpha was set at p - values of <0.05. RESULTS: Of the 523 patients who meet the inclusion criteria, 137 (26.2%) were prescribed an SSRI, SNRI, or TCA. Patients with these prescriptions were more likely to have pseudarthrosis (p =0.008) but not a revision surgery due to pseudarthrosis (p =0.219). Additionally, these patients had worse 1-year postoperative mental component summary (MCS)-12 (p =0.015) and Neck Disability Index (NDI) (p =0.006). The multivariate logistic regression analysis identified SSRI/SNRI/TCA use (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.11-2.99; p =0.018) and construct length (OR, 1.91; 95% CI, 1.50-2.44; p <0.001) as pseudarthrosis predictors. A SSRI/SNRI/TCA prescription was a revision surgery predictor due to adjacent segment disease on univariate analysis (OR, 2.51; p =0.035) but not on multivariate logistic regression analysis (OR, 2.24; p =0.10). CONCLUSIONS: Patients taking serotonin reuptake-inhibiting antidepressants are at increased risk of worse postoperative outcome scores, including NDI and MCS-12, likely due to their underlying depression. This may contribute to their greater likelihood of having adjacent segment surgery. Additionally, preoperative use of serotonin reuptake inhibitors in patients undergoing an ACDF is a predictor of radiographic pseudarthrosis but not pseudarthrosis revision.

Evaluating the Effect of Gastroesophageal Reflux Disease on Postoperative Dysphagia Following Anterior Cervical Spine Surgery-A Prospective, Multicenter Study.

STUDY DESIGN: Prospective cohort study. OBJECTIVES: The purpose of this study was to prospectively evaluate the impact of a preoperative diagnosis of gastroesophageal reflux disease on the incidence and severity of postoperative dysphagia in a multicenter population. METHODS: After Institutional Review Board approval, written informed consent was obtained from all participating patients. Patients over 18 years of age who underwent an elective anterior cervical discectomy and fusion for a degenerative condition were prospectively enrolled at two academic centers from the years 2018 to 2020. Patients were separated into two groups: those with and without a preoperative diagnosis of GERD. Continuous variables were assessed using either an independent t-test or Mann Whitney U-test for parametric and non-parametric data. All categorical variables were compared using a chi-square test. RESULTS: A total of 116 patients met study criteria and were subsequently enrolled. Overall rates of postoperative dysphagia increased to 47.3% (n = 53) at 2-weeks but eventually decreased towards the preoperative prevalence of 25.0% at the 24-week mark. Patients with preoperative diagnosis of GERD had lower dysphagia severity scores on a continuous variable analysis in both the DSQ and EAT-10 surveys at 2-week follow-up in addition to the Bazaz survey at 24-week follow-up. Our follow up at 24-weeks was 85.7%. CONCLUSIONS: Our study shows that having a preoperative diagnosis of GERD has no significant effect on the incidence of dysphagia following ACDF. Nevertheless, having a preoperative diagnosis of GERD does seem to provide some protective effect on the severity of dysphagia that this patient population develops at multiple intervals over a 24-week postoperative period.

Impact of Prolonged Operative Duration on Postoperative Symptomatic Venous Thromboembolic Events After Thoracolumbar Spine Surgery.

OBJECTIVE: To determine the effect of operative duration on the rate of postoperative symptomatic venous thromboembolic (VTE) events in patients undergoing thoracolumbar spine fusion. METHODS: We identified all thoracolumbar spine fusion patients between 2012 and 2021. Operative duration was defined as time from skin incision to skin closure. A 1:1 propensity match was conducted incorporating patient and surgical characteristics. Logistic regression was performed to assess predictors of postoperative symptomatic VTE events. A receiver operating characteristic curve was created to determine a cutoff time for increased likelihood of VTE. RESULTS: We identified 101 patients with VTE and 1108 patients without VTE. Seventy-five patients with VTE were matched to 75 patients without VTE. Operative duration (339 vs. 262 minutes, P = 0.010) and length of stay (5.00 vs. 3.54 days, P = 0.008) were significantly longer in patients with a VTE event. Operative duration was an independent predictor of VTE on multivariate regression (odds ratio: 1.003, 95% confidence interval: 1.001-1.01, P = 0.021). For each additional hour of operative duration, the risk of VTE increased by 18%. A cutoff time of 218 minutes was identified (area under the curve [95% confidence interval] = 0.622 [0.533-0.712]) as an optimal predictor of increased risk for a VTE event. CONCLUSIONS: Operative duration significantly predicted symptomatic VTE, especially after surgical time cutoff of 218 minutes. Each additional hour of operative duration was found to increase VTE risk by 18%. We also identify the impact of VTE on 90-day readmission rates, suggesting significantly higher costs and opportunity for hospital acquired conditions, in line with prior literature.

Do Patient Outcomes Predict Loss to Long-Term Follow-Up After Spine Surgery?

OBJECTIVE: To determine if spine surgery patients with greater improvement in patient-reported outcomes measures (PROMs) at early postoperative follow-up are more likely to be lost to follow-up at the 1-year and 2-year postoperative visits. METHODS: All patients older than 18 years who underwent primary or revision decompression or fusion surgery for degenerative spinal conditions at an academic institution were retrospectively identified. Univariate analysis compared patient demographics, surgical factors, and changes in short-term and long-term postoperative PROMs (Neck Disability Index, Oswestry Disability Index, visual analog scale [VAS] neck, VAS arm, VAS back, VAS leg, and Short-Form 12 Physical and Mental Component Scores) across groups with and without 1 year and 2 years follow-up. Logistic regression isolated predictors of loss to follow-up. RESULTS: A total of 1412 patients were included. Younger patient age, primary surgery, and single surgical approach independently predicted loss at 1 year follow-up. Female sex predicted loss at 2 years follow-up, whereas multilevel fusion surgery predicted attendance at 2 years clinical follow-up. In patients lost at 1 year follow-up compared with those who attended, preoperative to 3-month Mental Component Score and VAS neck pain improvement was significantly greater. When comparing patients based on 2 years follow-up status, VAS back pain improvement at 1 year postoperatively was significantly greater in patients lost to 2 years follow-up. All other changes in PROMs did not differ significantly by 1 or 2 years follow-up attendance. CONCLUSIONS: Overall patient outcomes were not found to affect loss to long-term follow-up after spine surgery. The general lack of association between postoperative follow-up status and clinical outcome may limit bias introduced in retrospective PROM studies.

Clinical Outcomes of Robotic Versus Freehand Pedicle Screw Placement After One-to Three-Level Lumbar Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The purpose of this study is to compare patient-reported outcome measures (PROMs) for patients undergoing one-to three-level lumbar fusion using robotically assisted vs freehand pedicle screw placement. METHODS: Patients who underwent either robotically assisted or freehand pedicle screw placement for one-to three-level lumbar fusion surgery from January 1, 2014 to August 31, 2020 at a single academic institution were identified. Propensity score matching was performed based on demographic variables. Clinical and surgical outcomes were compared between groups. Recovery Ratios (RR) and the proportion of patients achieving the minimally clinically important difference (%MCID) were calculated for Oswestry Disability Index, PCS-12, MCS-12, VAS Back, and VAS Leg at 1 year. Surgical outcomes included complication and revision rates. RESULTS: A total of 262 patients were included in the study (85 robotic and 177 freehand). No significant differences were found in ΔPROM scores, RR, or MCID between patients who underwent robotically assisted vs freehand screw placement. The rates of revision (1.70% freehand vs 1.18% robotic, P = 1.000) and complications (.57% freehand vs 1.18% robotic, P = .546) were not found to be statically different between the 2 groups. Controlling for demographic factors, procedure type (robotic vs freehand) did not emerge as a significant predictor of ΔPROM scores on multivariate linear regression analysis. CONCLUSIONS: Robotically assisted pedicle screw placement did not result in significantly improved clinical or surgical outcomes compared to conventional freehand screw placement for patients undergoing one-to three-level lumbar fusion.