Relating preoperative MCS-12 to microdiscectomy outcomes.

PURPOSE: To determine the impact of poor mental health on patient-reported and surgical outcomes after microdiscectomy. METHODS: Patients ≥ 18 years who underwent a single-level lumbar microdiscectomy from 2014 to 2021 at a single academic institution were retrospectively identified. Patient-reported outcomes (PROMs) were collected at preoperative, three-month, and one-year postoperative time points. PROMs included the Oswestry Disability Index (ODI), Visual Analog Scale Back and Leg (VAS Back and VAS Leg, respectively), and the mental and physical component of the short form-12 survey (MCS and PCS). The minimum clinically important differences (MCID) were employed to compare scores for each PROM. Patients were categorized as having worse mental health or better mental health based on a MCS threshold of 50. RESULTS: Of 210 patients identified, 128 (61%) patients had a preoperative MCS score ≤ 50. There was no difference in 90-day surgical readmissions or spine reoperations within one year. At 3- and 12-month time points, both groups demonstrated improvements in all PROMs (p < 0.05). At three months postoperatively, patients with worse mental health had significantly lower PCS (42.1 vs. 46.4, p = 0.004) and higher ODI (20.5 vs. 13.3, p = 0.006) scores. Lower mental health scores were associated with lower 12-month PCS scores (43.3 vs. 48.8, p < 0.001), but greater improvements in 12-month ODI (- 28.36 vs. - 18.55, p = 0.040). CONCLUSION: While worse preoperative mental health was associated with lower baseline and postoperative PROMs, patients in both groups experienced similar improvements in PROMs. Rates of surgical readmissions and reoperations were similar among patients with varying preoperative mental health status.

The Effect of Muscle Quality on Outcomes after Microdiscectomy.

OBJECTIVES: To investigate the relationship between muscle quality and 1) patient-reported outcomes and 2) surgical outcomes after lumbar microdiscectomy surgery. METHODS: Adult patients (≥18 years) who underwent lumbar microdiscectomy from 2014 to 2021 at a single academic institution were identified. Outcomes were collected during the preoperative, 3-month, 6-month, and 1-year postoperative periods. Those included were the Oswestry Disability Index (ODI), Visual Analog Scale Back and Leg (VAS-Back and VAS-Leg, respectively), and the mental and physical component of the short-form 12 survey (MCS and PCS). Muscle quality was determined by 2 systems: the normalized total psoas area (NTPA) and a paralumbar-based grading system. Surgical outcomes including 90-day surgical readmissions and 1-year reoperations were also collected. RESULTS: Of the 218 patients identified, 150 had good paralumbar muscle quality and 165 had good psoas muscle quality. Bivariant analysis demonstrated no difference between groups regarding surgical outcomes (P > 0.05). Multivariable analysis demonstrated that better paralumbar muscle quality was not associated with any consistent changes in patient reported outcomes. Higher NTPA was associated with improved PCS at 6 months (est. = 6.703, [95% CI: 0.759-12.646], P = 0.030) and 12 months (est. = 6.625, [95% CI: 0.845-12.405], P = 0.027). There was no association between muscle quality and surgical readmissions or reoperations. CONCLUSIONS: Our analysis demonstrated that higher psoas muscle quality was associated with greater physical improvement postoperatively. Muscle quality did not affect surgical readmissions or reoperations. Additional studies are needed for further assessment of the implications of muscle quality on postoperative outcomes.

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.

Risk Factors for Postoperative Urinary Retention After Lumbar Fusion Surgery: Anesthetics and Surgical Approach.

INTRODUCTION: Postoperative urinary retention (POUR) after lumbar fusion surgery can lead to longer hospital stays and thus increased risk of developing other postoperative complications. Therefore, we aimed to determine the relationship between POUR and (1) surgical approach and (2) anesthetic agents, including sugammadex and glycopyrrolate. METHODS: After institutional review board approval, L4-S1 single-level lumbar fusion surgeries between 2018 and 2021 were identified. A 3:1 propensity match of patients with POUR to those without was conducted, controlling for patient age, sex, diabetes status, body mass index, smoking status, history of benign prostatic hyperplasia, and the number of levels decompressed. POUR was defined as documented straight catheterization yielding >400 mL. We compared patient demographic, surgical, anesthetic, and postoperative characteristics. A bivariant analysis and backward multivariable stepwise logistic regression analysis ( P -value < 0.200) were performed. Significance was set to P < 0.05. RESULTS: Of the 899 patients identified, 51 met the criteria for POUR and were matched to 153 patients. No notable differences were observed between groups based on demographic or surgical characteristics. On bivariant analysis, patients who developed POUR were more likely to have been given succinylcholine (13.7% vs. 3.92%, P = 0.020) as an induction agent. The independent predictors of POUR identified by multivariable analysis included the use of succinylcholine {odds ratio (OR), 4.37 (confidence interval [CI], 1.26 to 16.46), P = 0.022} and reduced postoperative activity (OR, 0.99 [CI, 0.993 to 0.999], P = 0.049). Factors protective against POUR included using sugammadex as a reversal agent (OR, 0.38 [CI, 0.17 to 0.82], P = 0.017). The stepwise regression did not identify an anterior surgical approach as a notable predictor of POUR. CONCLUSION: We demonstrate that sugammadex for anesthesia reversal was protective against POUR while succinylcholine and reduced postoperative activity were associated with the development of POUR. In addition, we found no difference between the anterior or posterior approach to spinal fusion in the development of POUR.

Does the Severity of Foraminal Stenosis Impact Outcomes of Lumbar Decompression Surgery?

OBJECTIVE: To establish the relationship between the magnitude of foraminal stenosis and 1) improvement in patient-reported outcomes, 2) improvement in motor function after lumbar decompression surgery, and 3) difference in surgical outcomes. METHODS: Patients who underwent one-level posterior lumbar decompression for radiculopathy were retrospectively identified. Patient demographics and surgical characteristics were collected through a query search and manual chart review of the electronic medical records. Foraminal stenosis was determined on magnetic resonance imaging and graded using Lee et al.'s validated methodology as none, mild, moderate, or severe. Surgical outcomes, motor function, and patient-reported outcome measures (PROMs) were compared based on the amount of stenosis (mild vs. moderate vs. severe). Bivariant and multivariant analyses were performed. RESULTS: Severe stenosis demonstrated more 90-day readmissions (0.00% vs. 0.00% vs. 8.57%, respectively, P = 0.019), though this effect did not remain significant on multivariate analysis (P = 0.068). There was no association between stenosis severity and the degree of functional impairment or PROMs preoperatively. Patients with moderate or severe preoperative foraminal stenosis showed improvement in all PROMs after surgery (P < 0.05) except the mental component of the Short Form 12 survey. Notably, central stenosis grade was insignificantly different between groups (P = 0.358). Multivariable logistic regression analysis did not identify any significant independent predictors of surgical outcomes or changes in PROMs. CONCLUSIONS: We demonstrated that regardless of foraminal stenosis severity preoperatively, patients have a similar improvement in PROMs, surgical outcomes, and restoration of motor function after lumbar decompression surgery for radiculopathy.

The Impact of Physical Therapy After Lumbar Fusion Surgery.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: To determine if outcomes varied between patients based on physical therapy (PT) attendance after lumbar fusion surgery. SUMMARY OF BACKGROUND DATA: The literature has been mixed regarding the efficacy of postoperative PT to improve disability and back pain, as measured by patient-reported outcome measures. Given the prevalence of PT referrals and lack of high-quality evidence, there is a need for additional studies investigating the efficacy of PT after lumbar fusion surgery to aid in developing robust clinical guidelines. METHODS: We retrospectively identified patients receiving lumbar fusion surgery by current procedural terminology codes and separated them into 2 groups based on whether PT was prescribed. Electronic medical records were reviewed for patient and surgical characteristics, PT utilization, and surgical outcomes. Patient-reported outcome measures (PROMs) were identified and compared preoperatively, at 90 days postoperatively and one year postoperatively. RESULTS: The two groups had similar patient characteristics and comorbidities and demonstrated no significant differences between readmission, complication, and revision rates after surgery. Patients that attended PT had significantly more fused levels (1.41 ± 0.64 vs. 1.32 ± 0.54, P =0.027), longer operative durations (234 ± 96.4 vs. 215 ± 86.1 min, P =0.012), and longer postoperative hospital stays (3.35 ± 1.68 vs. 3.00 ± 1.49 days, P =0.004). All groups improved similarly by Oswestry Disability Index, short form-12 physical and mental health subsets, and back and leg pain by Visual Analog Scale at 90-day and 1-year follow-up. CONCLUSION: Our data suggest that physical therapy does not significantly impact PROMs after lumbar fusion surgery. Given the lack of data suggesting clear benefit of PT after lumbar fusion, surgeons should consider more strict criteria when recommending physical therapy to their patients after lumbar fusion surgery. LEVEL OF EVIDENCE: Level-Ⅲ.

The Implication of Preoperative Central Stenosis on Patient-Reported Outcomes After Lumbar Decompression Surgery.

OBJECTIVE: To assess the impact of central stenosis severity on patient-reported outcomes after lumbar decompression. METHODS: Patient diagnosis, demographics, and surgical characteristics were collected via query search and manual chart review of electronic medical records. The inclusion criteria were posterior lumbar decompressions from 2014-2020, with accessible magnetic resonance imaging reports. As previously validated by Lee et al., central stenosis was determined on magnetic resonance imaging and graded as none, mild, moderate, or severe. Patients were dichotomized into 2 groups to improve statistical power for comparisons: none or mild central stenosis and moderate or severe central stenosis. Patient-reported outcome measures (PROMs) were compared between cohorts at 1 year postoperatively. Statistical significance was set at P < 0.05. RESULTS: On bivariate analysis, no significant differences were noted between cohorts with regard to preoperative, 1-year postoperative, and delta PROMs. In addition, no significant difference in the number of patients attaining minimal clinically important difference (MCID) for each PROM was noted between cohorts. With the exception of mental score of the Short Form-12 survey, all intragroup preoperative to postoperative PROMs indicated significant improvement (all P < 0.05) after lumbar decompression surgery. Multivariate regression identified moderate or severe central canal stenosis as a significant independent predictor of improvement in visual analog scale back (estimate = -1.464, P = 0.045). CONCLUSIONS: We demonstrate that patients with moderate or severe central spinal stenosis may have more improvement in back pain than those with mild or no central stenosis after lumbar spine decompression surgery.

Predictors of Blood Transfusion in Patients Undergoing Lumbar Spinal Fusion.

OBJECTIVE: To determine risk factors for perioperative blood transfusion after lumbar fusion surgery. METHODS: After institutional review board approval, a retrospective cohort study of adult patients who underwent lumbar fusion at a single, urban tertiary academic center was retrospectively retrieved. Our primary outcome, blood transfusion, was collected via chart query. A receiver operating characteristic curve was used to evaluate the regression model. A P-value < 0.05 was considered statistically significant. RESULTS: Of the 3,842 patients, 282 (7.3%) required a blood transfusion. For patients undergoing posterolateral decompression and fusion, predictors of transfusion included age (P < 0.001) and more levels fused (P < 0.001). A higher preoperative hemoglobin level (P < 0.001) and revision surgery (P = 0.005) were protective of blood transfusion. For patients undergoing transforaminal lumbar interbody fusion, greater Elixhauser comorbidity index (P < 0.001), longer operative time (P = 0.040), and more levels fused (P = 0.030) were independent predictors of the need for blood transfusion. Patients with a higher body mass index (P = 0.012) and preoperative hemoglobin level (P < 0.001) had a reduced likelihood of receiving a transfusion. For circumferential fusion, greater age (P = 0.006) and longer operative times (P = 0.015) were independent predictors of blood transfusion, while a higher preoperative hemoglobin level (P < 0.001) and male sex (P = 0.002) were protective. CONCLUSIONS: Our analysis identified older age, lower body mass index, greater Elixhauser comorbidity index, longer operative duration, more levels fused, and lower preoperative hemoglobin levels as independent predictors of requiring a blood transfusion following lumbar spinal fusion. Different surgical approaches were not found to be associated with transfusion.

Risk factors for distal junctional failure in long-construct instrumentation for adult spinal deformity.

PURPOSE: The aim of this study is to identify risk factors associated with postoperative DJF in long constructs for ASD. METHODS: A retrospective review was performed at a tertiary referral spine centre from 01/01/2007 to 31/12/2016. Demographic, clinical and radiographic parameters were collated for patients with DJF in the postoperative period and compared to those without DJF. Survival analyses were performed using univariate logistic regression to identify variables with a p value < 0.05 for inclusion in multivariate analysis. Spearman's correlations were performed where applicable. RESULTS: One hundred two patients were identified. 41 (40.2%) suffered DJF in the postoperative period, with rod fracture being the most common sign of DJF (13/65; 20.0%). Mean time to failure was 32.4 months. On univariate analysis, pedicle subtraction osteotomy (p = 0.03), transforaminal lumbar interbody fusion (p < 0.001), pre-op LL (p < 0.01), pre-op SVA (p < 0.01), pre-op SS (p = 0.02), postop LL (p = 0.03), postop SVA (p = 0.01), postop PI/LL (p < 0.001), LL correction (p < 0.001), SVA correction (p < 0.001), PT correction (p = 0.03), PI/LL correction (p < 0.001), SS correction (p = 0.03) all proved significant. On multivariate analysis, pedicle subtraction osteotomy (OR 27.3; p = 0.03), postop SVA (p < 0.01) and LL correction (p = 0.02) remained statistically significant as independent risk factors for DJF. CONCLUSION: Recently, DJF has received recognition as its own entity due to a notable postoperative incidence. Few studies to date have evaluated risk factors for DJF. The results of our study highlight that pedicle subtraction osteotomy, poor correction of lumbar lordosis, and sagittal vertical axis are significantly associated with postoperative occurrence of DJF.

Patients From Socioeconomically Distressed Communities Experience Similar Clinical Improvements Following Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective cohort. OBJECTIVES: The aim was to compare patient-reported outcome measures (PROMs) following anterior cervical discectomy and fusion (ACDF) when categorizing patients based on socioeconomic status. Secondarily, we sought to compare PROMs based on race. SUMMARY OF BACKGROUND DATA: Social determinants of health are believed to affect outcomes following spine surgery, but there is limited literature on how combined socioeconomic status metrics affect PROMs following ACDF. MATERIALS AND METHODS: The authors identified patients who underwent primary elective one-level to four-level ACDF from 2014 to 2020. Patients were grouped based on their distressed community index (DCI) quintile (Distressed, At-Risk, Mid-tier, Comfortable, and Prosperous) and then race (White or Black). Multivariate regression for ∆PROMs was performed based on DCI group and race while controlling for baseline demographics and surgical characteristics. RESULTS: Of 1204 patients included in the study, all DCI groups improved across all PROMs, except mental health component score (MCS-12) for the Mid-tier group ( P =0.091). Patients in the Distressed/At-Risk group had worse baseline MCS-12, visual analog scale (VAS) Neck, and neck disability index (NDI). There were no differences in magnitude of improvement between DCI groups. Black patients had significantly worse baseline VAS Neck ( P =0.002) and Arm ( P =0.012) as well as worse postoperative MCS-12 ( P =0.016), PCS-12 ( P =0.03), VAS Neck ( P <0.001), VAS Arm ( P =0.004), and NDI ( P <0.001). Multivariable regression analysis did not identify any of the DCI groupings to be significant independent predictors of ∆PROMs, but being White was an independent predictor of greater improvement in ∆PCS-12 (ß=3.09, P =0.036) and ∆NDI (ß=-7.32, P =0.003). CONCLUSIONS: All patients experienced clinical improvements regardless of DCI or race despite patients in Distressed communities and Black patients having worse preoperative PROMs. Being from a distressed community was not an independent predictor of worse improvement in any PROMs, but Black patients had worse improvement in NDI compared with White patients. LEVEL OF EVIDENCE: 3.

Achieving Lumbar Fusion: An Evidence-Based Approach to Selecting Technique, Implants, and Biologics.

Many options currently exist for achieving lumbar fusion. A variety of techniques have been described. The challenge for spine surgeons is choosing which approach is ideal for the given circumstances, and to do this, a good understanding of the available evidence is necessary. The evidence regarding fusion approach, interbody cage utilization, bone grafting, biologics, and osteoporosis is reviewed.

How Do Patients With Predominant Neck Pain Improve After Anterior Cervical Discectomy and Fusion for Cervical Radiculopathy?

BACKGROUND: The presence of predominant pain in the arm vs the neck as a predictor of postoperative outcomes after anterior cervical discectomy and fusion (ACDF) has been seldom reported; therefore, the purpose of this study was to determine whether patients with predominant neck pain improve after surgery compared to patients with predominant arm pain or those with mixed symptoms in patients undergoing ACDF for radiculopathy. METHODS: A retrospective cohort study was conducted on patients who underwent ACDF at a single center from 2016 to 2018. Patients were split into groups based on preoperative neck and arm pain scores: neck (N) pain dominant group (visual analog scale [VAS] neck ≥ VAS arm by 1.0 point); neutral group (VAS neck < VAS arm by 1.0 point); or arm (A) pain dominant group (VAS arm ≥ VAS neck by 1.0 point), using a threshold difference of 1.0 point. Subsequently, individuals were substratified into 2 groups based on the arm to neck pain ratio (ANR): non-arm pain dominant defined as ANR ≤1.0 and arm pain dominant (APD) defined as ANR >1.0. Patient-reported outcome measurements including Neck Disability Index (NDI), Physical Component Score-12, and Mental Component Score (MCS-12) were compared between groups. RESULTS: No significant differences between groups when stratifying patients using a threshold difference of 1.0 point. When stratifying patients using the ANR, those in the APD group had significantly higher postoperative MCS-12 (P = 0.008) and NDI (P = 0.011) scores. In addition, the APD group showed a greater magnitude of improvement for MCS-12 and NDI scores (P = 0.043 and P = 0.038, respectively). Multiple linear regression showed that the A and the APD groups were both independent predictors of improvement in NDI. CONCLUSION: Patients with dominant arm pain showed significantly greater improvement in terms of MCS-12 and NDI scores compared to patients with dominant neck pain. CLINICAL RELEVANCE: To compare the impact of ACDF on arm and neck pain in the context of cervical radiculopathy using patient-reported outcome measures as an objective measurement.

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.

Do Patients with Back Pain-Dominant Symptoms Improve After Lumbar Surgery for Radiculopathy or Claudication?

BACKGROUND: Currently, few studies have examined whether patients with back or leg pain-predominant symptoms fare better clinically after lumbar spine surgery; therefore, the purpose of this study was to determine whether patients with back pain-dominant symptoms improved to a similar degree as patients with mixed or leg pain-dominant symptoms after lumbar surgery. METHODS: A retrospective cohort study was conducted at a single academic center, in which patients were stratified into three groups: (1) back pain-dominant group (B) (visual analog score [VAS] back - VAS leg ≥ 1.0 point), (2) neutral group (N) (VAS back - VAS leg < 1.0 point), or (3) leg pain-dominant group (L) (VAS leg - VAS back ≥ 1.0 point), using a VAS threshold difference of 1.0 point. As a secondary analysis, the VAS leg-to-back pain (LBR) ratio was used to further stratify patients: (1) nonleg pain-dominant (NLPD) group (LBR ≤ 1.0) or (2) leg pain-dominant (LPD) group (LBR > 1.0). Patient outcomes, including physical component score of the short form-12 survey (PCS-12), mental component score of the short form-12 survey (MCS-12), and Oswestry Disability Index (ODI), were identified and compared between groups using univariate and multivariate analysis. RESULTS: There were no significant differences in preoperative, postoperative, or delta scores for PCS-12 or ODI scores between groups. In patients undergoing decompression surgery, those with back pain-dominant or mixed symptoms (B, N, or NLPD groups) did not improve with respect to MCS-12 scores after surgery (P > .05), and those with leg pain-dominant symptoms (LPD group) had greater delta MCS-12 scores (P = .046) and greater recovery rates (P = .035). Multiple linear regression did not find LPD to be an independent predictor of PCS-12 or ODI scores. CONCLUSION: Patients undergoing lumbar decompression surgery and leg pain-dominant symptoms noted a greater improvement in MCS-12 scores; however, there were no differences in PCS-12 or ODI scores. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Patients undergoing lumbar decompression surgery demonstrate no major clinically significant differences when split up by pain-dominance groups.

A Systematic Review of Risk Factors Associated With Distal Junctional Failure in Adult Spinal Deformity Surgery.

BACKGROUND: The surgical management of adult spinal deformity (ASD) is a major surgical undertaking associated with considerable perioperative risk and a substantial complication profile. Although the natural history and risk factors associated with proximal junctional kyphosis (PJK) and proximal junctional failure are widely reported, distal junctional failure (DJF) is less well understood. STUDY DESIGN: A systematic review was carried out. OBJECTIVES: The primary objective is to identify the risk factors associated with DJF. The secondary objective is to delineate the incidence rate and causative factors associated with DJF. METHODS: A systematic review of articles in Medline/PubMed and The Cochrane Library databases was performed according to preferred reporting items for systematic reviews and meta-analyses guidelines. Data was collated to determine the prevalence of DJF and overall revision rates, and identify potential risk factors for development of DJF. RESULTS: Twelve studies were included for systematic review. There were 81/2261 (3.6%) cases of DJF. Overall, DJF represented 27.3% of all revision surgeries. Anterior-posterior surgery had a reduced incidence of postoperative DJF [5.0% vs. 8.7%; P=0.08; relative risk (RR)=1.73], as did patients below 60 years of age at the time of surgery (2.9% vs. 3.9%; P=0.09; RR=1.34). There was a higher incidence of DJF among those patients who received interbody fusion (9.9% vs. 5.1%; P=0.06; RR=1.93) compared with those who did not. However, none of these findings reached statistical significance. There were significantly more rates of DJF for fusions ending on L5 compared with constructs fused to the sacrum (11.7% vs. 3.6%; P=0.02; RR=3.28). CONCLUSIONS: Cohorts 60 years and above of age at the time of surgery and patients managed with posterior-only fusion or interbody fusion have increased incidences of DJF. Fusion to L5 instead of the sacrum significantly influences DJF rates. However, the quality of available evidence is low and further high-quality studies are required to more robustly analyze the clinical, radiographic, and surgical risk factors associated with the development of DJF after ASD surgery.

Radiographic Measures of Spinal Alignment Are Not Predictive of the Development of C5 Palsy Following Anterior Cervical Discectomy and Fusion Surgery.

BACKGROUND: Postoperative C5 palsy is a common complication following cervical decompression, occurring more frequently after posterior-based procedures. It has been theorized that this is the result of C5 nerve stretch resulting from spinal cord drift with these procedures. As such, it is thought to be less common after anterior cervical decompression and fusion (ACDF). However, no consensus has been reached on its true etiology. The purpose of this study is to assess the rate of C5 palsy following ACDF and to determine whether any radiographic or demographic parameters were predictive of its development. METHODS: Two hundred and twenty-six patients who received ACDF between September 2015 and September 2016 were reviewed, and 122 were included in the final analysis. Patient demographic, surgical, and radiographic data were analyzed, including preoperative and postoperative radiographic and motor examination results. The Mann-Whitney U test was used to compare continuous variables between independent groups, and Fisher's exact test was used to compare categorical variables between groups. RESULTS: Seven patients developed a C5 palsy in the postoperative period, an incidence rate of 5.7%. Among the radiographic parameters evaluated, there were no statistically significant differences between the C5 palsy and nonpalsy groups. Additionally, there were no statistically significant differences in age, patient sex, or numbers of vertebral levels fused between groups. CONCLUSIONS: Ultimately, we did not identify any statistically significant demographic or radiographic predictive factors for the development of C5 palsy following ACDF surgery. LEVEL OF EVIDENCE: 3.

Lumbar Pedicle Morphology and Vertebral Dimensions in Isthmic and Degenerative Spondylolisthesis-A Comparative Study.

BACKGROUND: The pedicle screw is the most common device used to achieve fixation in fusion of spondylolistheses. Safe and accurate placement with this technique relies on a thorough understanding of the bony anatomy. There is a paucity of literature comparing the surgically relevant osseous anatomy in patients with a degenerative spondylolisthesis (DS) and an isthmic spondylolisthesis (IS). The goal of this study was to determine the differences in the osseous anatomy in patients with a DS and those with an IS. METHODS: A retrospective comparative cohort study was conducted on patients with a single-level, symptomatic L4-L5 DS or a single-level, symptomatic L5-S1 IS. Magnetic resonance imaging for these patients was reviewed. Morphometries of the pedicle and vertebral body were analyzed by 2 independent observers for the levels from L3 to S1, and radiographic parameters were compared between groups. RESULTS: A total of 572 levels in 143 patients were studied, including 103 patients with a DS and 40 with an IS. After accounting for confounders, IS and DS had an independent effect on transverse vertebral body width, pedicle height and width, and sagittal pedicle angle. Patients with an IS had a smaller pedicle height (P < .001) and pedicle width (P = .001) than patients with DS. In addition, the angulation of the pedicles varied on the basis of the diagnosis. CONCLUSIONS: The osseous anatomy is significantly different in patients with a DS than with an IS. Patients with an IS have smaller pedicles in the lumbar spine. Also, the L4 and L5 pedicles are more caudally angulated and the S1 pedicle is less medialized. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Understanding the differences in pedicle anatomy is important for the safe placement of pedicle screws.

Patient Outcomes Following Short-segment Lumbar Fusion Are Not Affected by PI-LL Mismatch.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: The objective of this study was to further elucidate the relationship between pelvic incidence-lumbar lordosis (PI-LL) mismatch and surgical outcomes in patients undergoing short segment lumbar fusions for degenerative lumbar disease. SUMMARY OF BACKGROUND DATA: There are few studies examining the relationship between spinopelvic parameters and patient reported outcome measurements (PROMs) in short segment lumbar degenerative disease. MATERIALS AND METHODS: A retrospective review was conducted at single academic institution. Patients undergoing 1- or 2-level lumbar fusion were retrospectively identified and separated into 2 groups based on postoperative PI-LL mismatch ≤10 degrees (NM) or PI-LL mismatch >10 degrees (M). Outcomes including the Physical Component Score (PCS)-12, Mental Component Score (MCS)-12, Oswestry Disability Index (ODI), Visual Analog Scale (VAS) back and leg scores were analyzed. Absolute PROM scores, the recovery ratio and the percentage of patients achieving minimum clinically important difference between groups were compared and a multiple linear regression analysis was performed. RESULTS: A total of 306 patients were included, with 59 patients in the NM group and 247 patients in the M group. Patients in the M group started with a higher degree of PI-LL mismatch compared with the NM group (22.2 vs. 7.6 degrees, P<0.001) and this difference increased postoperatively (24.7 vs. 2.5 degrees, P<0.001). There were no differences between the 2 groups in terms of baseline, postoperative, or Δ outcome scores (P>0.05). In addition, having a PI-LL mismatch was not found to be an independent predictor of any PROM on multivariate analysis (P>0.05). CONCLUSION: The findings in this study show that even though patients in the M group had a higher degree of mismatch preoperatively and postoperatively, there was no difference in PROMs. LEVEL OF EVIDENCE: Level III.

Surgical Management of Thoracolumbar Burst Fractures: Surgical Decision-making Using the AOSpine Thoracolumbar Injury Classification Score and Thoracolumbar Injury Classification and Severity Score.

The management of thoracolumbar burst fractures is controversial with no universally accepted treatment algorithm. Several classification and scoring systems have been developed to assist in surgical decision-making. The most widely accepted are the Thoracolumbar Injury Classification and Severity Score (TLICS) and AOSpine Thoracolumbar Injury Classification Score (TL AOSIS) with both systems designed to provide a simple objective scoring criteria to guide the surgical or nonsurgical management of complex injury patterns. When used in the evaluation and treatment of thoracolumbar burst fractures, both of these systems result in safe and consistent patient care. However, there are important differences between the 2 systems, specifically in the evaluation of the complete burst fractures (AOSIS A4) and patients with transient neurological deficits (AOSIS N1). In these circumstances, the AOSpine system may more accurately capture and characterize injury severity, providing the most refined guidance for optimal treatment. With respect to surgical approach, these systems provide a framework for decision-making based on patient neurology and the status of the posterior tension band. Here we propose an operative treatment algorithm based on these fracture characteristics as well as the level of injury.

BMI Does Not Affect Complications or Patient Reported Outcomes After Lumbar Decompression Surgery.

STUDY DESIGN: This is a retrospective comparative review. OBJECTIVE: The objective of this study was to identify the influence of body mass index (BMI) on postsurgical complications and patient reported outcomes measures (PROMs) following lumbar decompression surgery. SUMMARY OF BACKGROUND DATA: Current literature does not accurately identify the impact of BMI on postsurgical complications or outcomes. MATERIALS AND METHODS: Records from a single-center, academic hospital were used to identify patients undergoing 1 to 3-level lumbar decompression surgery. Patients under 18 years of age, those undergoing surgery for infection, trauma, tumor, or revision, and those with <1-year follow-up were excluded. Patients were split into groups based on preoperative BMI: class I: BMI <25.0 kg/m; class II: BMI 25.0-29.9 kg/m; class III: BMI 30.0-34.9 kg/m; and class IV: BMI >35.0 kg/m. Absolute PROM scores, the recovery ratio and the percent of patients achieving minimum clinically important difference between groups were compared and a multiple linear regression analysis was performed. RESULTS: A total of 195 patients were included with 34 (17.4%) patients in group I, 80 (41.0%) in group II, 49 (25.1%) in group III, and 32 (16.5%) in group IV. Average age was 60.0 (58.0, 62.0) years and average follow-up was 13.0 (12.6, 13.4) months. All patients improved significantly within each group, except for class III and class IV patients, who did not demonstrate significant improvements in terms of Mental Component Score (MCS-12) scores (P=0.546 and 0.702, respectively). There were no significant differences between BMI groups for baseline or postoperative PROM values, recovery ratio, or the percent of patients reaching minimum clinically important difference. Multiple linear regression analysis revealed that BMI was not a significant predictor for change in outcomes for any measure. The 30-day readmission rate was 6.2% and overall revision rate at final follow-up was 5.1%, with no significant differences between groups. CONCLUSION: This study's results suggest that BMI may not significantly affect complications or patient outcomes at 1-year in those undergoing lumbar decompression surgery. LEVEL OF EVIDENCE: Level III.