Impact of Insulin Dependence on Perioperative Outcomes Following Anterior Cervical Discectomy and Fusion

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

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

In patients undergoing elective anterior cervical discectomy and fusion (ACDF), we sought to determine the impact of screw length on: (1) radiographic pseudarthrosis, (2) pseudarthrosis requiring reoperation, and (3) patient-reported outcome measures (PROMs).

METHODS

A single-institution, retrospective cohort study was undertaken from 2010-21. The primary independent variables were: screw length (mm), screw length divided by the anterior-posterior vertebral body diameter (VB%), and the presence of any screw with VB% < 75% vs all screws with VB% ≥ 75%. Multivariable logistic regression controlled for age, BMI, gender, smoking, American Society of Anesthesiology grade, number of levels fused, and whether a corpectomy was performed.

RESULTS

Of 406 patients undergoing ACDF, levels fused were: 1-level (39.4%), 2-level (42.9%), 3-level (16.7%), and 4-level (1.0%). Mean screw length was 14.3 ± 2.3 mm, and mean VB% was 74.4 ± 11.2. A total of 293 (72.1%) had at least one screw with VB% < 75%, 113 (27.8%) had all screws with VB% ≥ 75%, and 141 (34.7%) patients had radiographic pseudarthrosis at 1-year. Patients who had any screw with VB% < 75% had a higher rate of radiographic pseudarthrosis compared to those had all screws with VB% ≥ 75% (39.6% vs 22.1%, P < .001). Multivariable logistic regression revealed that a higher VB% (OR = .97, 95%CI = .95-.99, P = .035) and having all screws with VB% ≥ 75% (OR = .51, 95%CI = .27-.95, P = .037) significantly decreased the odds of pseudarthrosis at 1-year, with no difference in reoperation or PROMs (all P > .05).

CONCLUSION

Longer screws taking up ≥75% of the vertebral body protected against radiographic pseudarthrosis at 1-year. Maximizing screw length in ACDF is an easily modifiable factor directly under the surgeon's control that may mitigate the risk of pseudarthrosis.

Adverse complications of cervical spinal fusion in patients with different types of diabetes mellitus: a retrospective nationwide inpatient sample database cross-sectional study

BACKGROUND

Diabetes mellitus (DM) is a prevalent chronic condition that influences spine surgery outcomes. The impact of type Ⅰ and type Ⅱ DM on adverse postoperative outcomes, mortality, prolonged length of stay (LOS), and increased in-hospital costs following cervical fusion surgery remains unclear in the past decade. This study aims to determine the specific effect of different classifications of DM on postoperative complications in patients experiencing cervical fusion surgery.

METHOD

Data from the Nationwide Inpatient Sample database was acquired between 2010 and 2019. Patients experiencing cervical fusion were included and classified as having type I DM, type II DM, or neither. Patient demographics, hospital characteristics, operative variables, comorbidities, complications, and other postoperative outcomes were assessed. Propensity score matching analysis was used to balance baseline differences. Univariate and multivariate logistic regression were employed to determine the risk of postoperative outcomes in patients with different classifications of DM.

RESULT

A total of 267 174 cervical spinal fusions were identified (224 255 were patients without DM, 670 patients had type I DM, and 42 249 patients had type II DM). After propensity score matching, the multivariate analysis of non-DM and type I DM patients shows a significant difference in pneumonia ( P =0.020). However, type Ⅱ DM served as an independent predictor of an increased risk of acute cerebrovascular disease ( P =0.001), acute myocardial infarction ( P =0.014), pneumonia ( P =0.045), continuous trauma ventilation ( P =0.016), chest pain ( P <0.001), urinary tract infection ( P <0.001), transfusion ( P =0.005) and dysphagia ( P =0.013), prolonged LOS ( P <0.001), and increased costs ( P =0.008).

CONCLUSION

Using non-DM patients as a reference, the type II DM group demonstrated a higher risk of postoperative complications than the type I DM group among patients receiving cervical fusion surgery. This vital distinction could enhance risk stratification and guidance for patients diagnosed with DM before cervical fusion surgery.

Insulin dependence negatively impacts outcomes in anterior cervical discectomy with fusions: a 10-year retrospective analysis

BACKGROUND CONTEXT

Although anterior cervical discectomy and fusion (ACDF) procedures for cervical spine disease have been increasing amid a growing diabetic patient population, there is a paucity of literature focusing on insulin-dependence as a risk-factor for postoperative ACDF complications.

PURPOSE

To evaluate the differential impact of insulin dependence on perioperative outcomes including total length of stay, surgical, and medical complications within thirty days following ACDF.

STUDY DESIGN/SETTING

A retrospective cohort, large multicenter database study.

PATIENT SAMPLE

The American College of Surgeons National Surgical Quality Improvement Program database was queried to retrospectively identify patients who had undergone ACDF between 2011 and 2021 using the Current Procedural Terminology code 22551.

OUTCOME MEASURES

Perioperative surgical and medical complications.

METHODS

The study population was divided into 3 groups 1) insulin-dependent diabetes mellitus (IDDM), 2) noninsulin-dependent diabetes mellitus (NIDDM), and 3) no diabetes mellitus (non-DM). One-way analysis of variance for continuous variables and chi-square tests for categorical variables were used to identify differences in perioperative variables between the 3 groups. Multivariable logistic regression analysis assessed the effect of diabetes mellitus status on postoperative medical and surgical outcomes.

RESULTS

A total of 85,758 ACDF procedures were identified between 2011 and 2021, of which 5,178 were IDDM, 9,652 were NIDDM, and 70,982 were non-DM. The rates of surgical and medical complication varied between the 3 groups. IDDM patients had the highest rates of at least one medical complication (6.1%). Only IDDM increased the risk for medical complications (OR: 1.320, 95% CI [1.144-1.518]) and extended hospital length of stay (LOS) (OR: 1.244, 95% CI [1.071-1.441]) following a multivariate logistic regression analysis.

CONCLUSION

Patients with IDDM were at an increased risk for postoperative medical complications and extended hospital LOS. Personalized postoperative management, guided by risk assessment is indicated for this population. These findings can be used to improve risk stratification and informed consent for DM patients who are insulin dependent.

Relationship between preoperative glucose level and all-cause mortality in patients with osteoporotic vertebral compression fracture who underwent percutaneous vertebroplasty

To investigate the relationship between preoperative blood glucose levels and long-term all-cause mortality in patients with osteoporotic vertebral compression fractures (OVCF) who underwent percutaneous vertebroplasty (VP). This single-center retrospective study involved a chart review of patients admitted for VP to treat OVCF between 2013 and 2020. Patients with pathological or multiple fractures or those who did not undergo bone mineral density assessment were excluded. All relevant information was collected from electronic medical records. The survival status of all patients was confirmed at the end of March 2021. Cox proportional hazard models with multivariate adjustments were used to examine the effects of blood glucose levels on all-cause mortality. Overall, 131 patients were retrospectively analyzed (mean age: 75.8 ± 9.3 years, male patients: 26.7%) with a median follow-up period of 2.1 years. Preoperative hyperglycemia (hazard ratio: 2.668, 95% confidence interval [CI] 1.064, 6.689; p = 0.036) and glucose levels (hazard ratio: 1.007, 95% CI 1.002-1.012; p = 0.006) were found to be independently associated with a higher risk of all-cause mortality. This correlation remained significant even after adjusting for age and sex, and other factors and comorbidities that might affect outcomes (hazard ratio: 2.708, 95% CI 1.047, 7.003, p = 0.040 and 1.007; 95% CI 1.001, 1.013, p = 0.016, respectively). Furthermore, a history of diabetes mellitus was not a significant factor influencing long-term all-cause mortality. Preoperative glucose levels were found to be independently associated with survival outcomes in patients with OVCF who underwent VP. Conversely, diabetes mellitus was not associated with long-term all-cause mortality. Our findings highlight that preoperative hyperglycemia is a risk factor for long-term mortality in this aging surgical population.

Clinicosocial determinants of hospital stay following cervical decompression: A public healthcare perspective and machine learning model

OBJECTIVE

Post-operative length of hospital stay (LOS) is a valuable measure for monitoring quality of care provision, patient recovery, and guiding hospital resource management. But the impact of patient ethnicity, socio-economic deprivation as measured by the indices of multiple deprivation (IMD), and pre-existing health conditions on LOS post-anterior cervical decompression and fusion (ACDF) is under-researched in public healthcare settings.

METHODS

From 2013 to 2023, a retrospective study at a single center reviewed all ACDF procedures. We analyzed 14 non-clinical predictors-including demographics, comorbidities, and socio-economic status-to forecast a categorized LOS: short (≤2 days), medium (2-3 days), or long (>3 days). Three machine learning (ML) models were developed and assessed for their prediction reliability.

RESULTS

2033 ACDF patients were analyzed; 79.44 % had a LOS ≤ 2 days. Significant predictors of LOS included patient sex (HR:0.81[0.74-0.88], p < 0.005), IMD decile (HR:1.38[1.24-1.53], p < 0.005), smoking (HR:1.24[1.12-1.38], p < 0.005), DM (HR:0.70[0.59-0.84], p < 0.005), and COPD (HR:0.66, p = 0.01). Asian patients had the highest mean LOS (p = 0.003). Testing on 407 patients, the XGBoost model achieved 80.95 % accuracy, 71.52 % sensitivity, 85.76 % specificity, 71.52 % positive predictive value, and a micro F1 score of 0.715. This model is available at: https://acdflos.streamlit.app.

CONCLUSIONS

Utilizing non-clinical pre-operative parameters such as patient ethnicity, socio-economic deprivation index, and baseline comorbidities, our ML model effectively predicts postoperative LOS for patient undergoing ACDF surgeries. Yet, as the healthcare landscape evolves, such tools will require further refinement to integrate peri and post-operative variables, ensuring a holistic decision support tool.

Risk Factors of Nonfusion after Anterior Cervical Decompression and Fusion in the Early Postoperative Period: A Retrospective Study

OBJECTIVE

Although high fusion rates have been reported for anterior cervical decompression and fusion (ACDF) in the medium and long term, the risk of nonfusion in the early period after ACDF remains substantial. This study investigates early risk factors for cage nonfusion in patients undergoing single- or multi-level ACDF.

METHODS

This was a retrospective study. From August 2020 to December 2021, 107 patients with ACDF, including 197 segments, were enrolled, with a follow-up of 3 months. Among the 197 segments, 155 were diagnosed with nonfusion (Nonfusion group), and 42 were diagnosed with fusion (Fusion group) in the early period after ACDF. We assessed the significance of the patient-specific factors, radiographic indicators, serum factors, and clinical outcomes. The Wilcoxon rank sum test, t-tests, analysis of variance, and stepwise multivariate logistic regression were used for statistical analysis.

RESULTS

Univariate analysis showed that smoking, insufficient improvement in the C2-7 Cobb angle (p = 0.024) and the functional spinal unit Cobb angle (p = 0.022) between preoperative and postoperative stages and lower serum calcium (fusion: 2.34 ± 0.12 mmol/L; nonfusion: 2.28 ± 0.17 mmol/L, p = 0.003) β-carboxyterminal telopeptide end of type 1 collagen (β-CTX) (fusion: 0.51 [0.38, 0.71]; nonfusion: 0.43 [0.31, 0.57], p = 0.008), and N-terminal fragment of osteocalcin (N-MID-BGP) (fusion: 18.30 [12.15, 22.60]; nonfusion: 14.45 [11.65, 18.60], p = 0.023) are risk factors for nonfusion in the early period after ACDF. Stepwise logistic regression analysis revealed that poor C2-7 Cobb angle improvement (odds ratio [OR], 1.107 [1.019-1.204], p = 0.017) and lower serum calcium (OR, 3.700 [1.138-12.032], p = 0.030) are risk factors.

CONCLUSIONS

Patients with successful fusion after ACDF had higher preoperative serum calcium and improved C2-7 Cobb angle than nonfusion patients at 3 months. These findings suggest that serum calcium could be used to identify patients at risk of nonfusion following ACDF and that correcting the C2-7 Cobb angle during surgery could potentially increase fusion in the early period after ACDF.

Postoperative short-term mortality between insulin-treated and non-insulin-treated patients with diabetes after non-cardiac surgery: a systematic review and meta-analysis

BACKGROUND

Diabetes mellitus is an independent risk factor for postoperative complications. It has been reported that insulin-treated diabetes is associated with increased postoperative mortality compared to non-insulin-treated diabetes after cardiac surgery; however, it is unclear whether this finding is applicable to non-cardiac surgery.

OBJECTIVE

We aimed to assess the effects of insulin-treated and non-insulin-treated diabetes on short-term mortality after non-cardiac surgery.

METHODS

Our study was a systematic review and meta-analysis of observational studies. PubMed, CENTRAL, EMBASE, and ISI Web of Science databases were searched from inception to February 22, 2021. Cohort or case-control studies that provided information on postoperative short-term mortality in insulin-treated diabetic and non-insulin-treated diabetic patients were included. We pooled the data with a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation system was used to rate the quality of evidence.

RESULTS

Twenty-two cohort studies involving 208,214 participants were included. Our study suggested that insulin-treated diabetic patients was associated with a higher risk of 30-day mortality than non-insulin-treated diabetic patients [19 studies with 197,704 patients, risk ratio (RR) 1.305; 95% confidence interval (CI), 1.127 to 1.511; p < 0.001]. The studies were rated as very low quality. The new pooled result only slightly changed after seven simulated missing studies were added using the trim-and-fill method (RR, 1.260; 95% CI, 1.076-1.476; p = 0.004). Our results also showed no significant difference between insulin-treated diabetes and non-insulin-treated diabetes regarding in-hospital mortality (two studies with 9,032 patients, RR, 0.970; 95% CI, 0.584-1.611; p = 0.905).

CONCLUSION

Very-low-quality evidence suggests that insulin-treated diabetes was associated with increased 30-day mortality after non-cardiac surgery. However, this finding is non-definitive because of the influence of confounding factors.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021246752, identifier: CRD42021246752.

The Effect of Diabetes and Metabolic Syndrome on Spine Surgery Outcomes

PURPOSE OF REVIEW

Diabetes and metabolic syndrome are highly prevalent in patients undergoing spine surgery. This review aims to capture both the findings of recently published literature investigating the effects of diabetes and metabolic syndrome on spine surgery outcomes and the current best practices in patient management.

RECENT FINDINGS

Diabetes and metabolic syndrome both contribute to worse outcomes in patients undergoing spine surgery. Although patients with diabetes are at greater risk of complications, those with uncontrolled diabetes experience increased healthcare costs and greater odds of postoperative complications. Furthermore, metabolic syndrome is repeatedly shown to have an adverse effect on spine surgery outcomes, including healthcare costs and medical complications. Spine surgeons should coordinate care with primary care physicians to optimize the preoperative profile of patients with comorbidities like diabetes and metabolic syndrome to minimize operative risk. With the shift to value-based care, understanding the patient factors that lead to complications is becoming increasingly important. Future studies should build upon the current literature and design preoperative interventions for at-risk patients. Additionally, further research is needed to analyze the modulatory effects of the social determinants of health in patients with diabetes and metabolic syndrome.

Patients with insulin-dependent diabetes are at greater risk for perioperative adverse outcomes following total hip arthroplasty

BACKGROUND

The prevalence of diabetes mellitus (DM) continues to increase among patients undergoing total hip arthroplasty (THA). It is unclear how insulin use is correlated with risk for adverse outcomes.

METHODS

A cohort of 146,526 patients undergoing primary THA were identified in the 2005-2017 National Surgical Quality Improvement Program database. Patients were classified as insulin-dependent diabetic (IDDM), non-insulin-dependent diabetic (NIDDM), or not diabetic. Multivariate analyses were used.

RESULTS

Compared to patients without diabetes, patients with NIDDM were at increased risk for 4 of 17 perioperative adverse outcomes studied. Patients with IDDM were at increased risk for those 4 and 8 additional adverse outcomes (12 of the 17 studied).

CONCLUSION

These findings have important implications for preoperative risk stratification and quality improvement initiatives.

The Impact of Diabetes on Outcomes and Health Care Costs Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Anterior cervical discectomy and fusion (ACDF) is commonly used to treat an array of cervical spine pathology and is associated with good outcomes and low complication rates. Diabetes mellitus (DM) is a common comorbidity for patients undergoing ACDF, but the literature is equivocal about the impact it has on outcomes. Because DM is a highly prevalent comorbidity, it is crucial to determine if it is an associated risk factor for outcomes after ACDF procedures.

METHODS

Patients at a single institution from 2008 to 2016 undergoing ACDF were compared on the basis of having a prior diagnosis of DM versus no DM. The 2 cohorts were compared utilizing univariate tests and multivariate logistic and linear regressions.

RESULTS

Data for 2470 patients was analyzed. Diabetic patients had significantly higher Elixhauser scores (P < .0001). Univariate testing showed diabetic patients were more likely to suffer from sepsis (0.82% vs 0.10%, P = .03) and bleeding complications (3.0% vs 1.5%, P = .04). In multivariate analyses, diabetic patients had higher rates of non-home discharge (odds ratio [OR] = 1.37, 95% confidence interval [CI] = 1.07-1.75, P = .013) and prolonged length of stay (OR = 1.95, 95% CI = 1.25-3.05, P = .003), but similar complication (OR = 1.46, 95% CI = 0.85-2.52, P = .17), reoperation (OR = 0.77, 95% CI = 0.33-1.81, P = .55), and 90-day readmission (OR = 1.53, 95% CI = 0.97-2.43) rates compared to nondiabetic patients. Direct cost was also shown to be similar between the cohorts after adjusting for patient, surgical, and hospital-related factors (estimate = -$30.25, 95% CI = -$515.69 to $455.18, P = .90).

CONCLUSIONS

Diabetic patients undergoing ACDF had similar complication, reoperation, and readmission rates, as well as similar cost of care compared to nondiabetic patients.

Systematic Review of Literature Examining Bacterial Urinary Tract Infections in Diabetes

This systematic review addresses the central research question, "what is known from the published, peer-reviewed literature about the impact of diabetes on the risk of bacterial urinary tract infections (UTI)?" We examine the results from laboratory studies where researchers have successfully adapted mouse models of diabetes to study the pathophysiology of ascending UTI. These studies have identified molecular and cellular effectors shaping immune defenses against infection of the diabetic urinary tract. In addition, we present evidence from clinical studies that in addition to diabetes, female gender, increased age, and diabetes-associated hyperglycemia, glycosuria, and immune impairment are important risk factors which further increase the risk of UTI in diabetic individuals. Clinical studies also show that the uropathogenic genera causing UTI are largely similar between diabetic and nondiabetic individuals, although diabetes significantly increases risk of UTI by drug-resistant uropathogenic bacteria.

Is the fusion order of the cranial and caudal levels different in two-level anterior cervical discectomy and fusion for cervical spondylopathy? A retrospective study

STUDY DESIGN

Retrospective study.

OBJECTIVE

This study aimed to compare the fusion order between the cranial and caudal levels in two-level anterior cervical discectomy and fusion (ACDF) with a zero-profile device in the treatment of cervical spondylopathy. Fusion is the standard used to judge the success of ACDF. However, the fusion order in two-level ACDF remains uncertain. The mechanical environment of different levels is different, which may affect the fusion rate or fusion order.

METHODS

From 2014 to January 2019, data of consecutive patients with two-level cervical disk degenerative disease who underwent ACDF were retrospectively reviewed. Radiological assessments were based on the range of motion of the fusion level, segment slope, and disk height, and complications were assessed. Data were analyzed using the paired t, Mann-Whitney U, χ2, Fisher exact, and rank-sum tests and logistic regression analysis.

RESULTS

In total, 118 patients were ultimately enrolled for analysis in the study. The respective fusion rates of the cranial and caudal levels were 26.27% and 10.17% (p < 0.05) at 3 months, 58.47% and 42.37% (p < 0.05) at 6 months, 86.44% and 82.20% (1 0.05) at 1 year, and 92.37% and 89.83% (p > 0.05) at the last follow-up. Multivariate logistic regression analysis indicated that the preoperative segmental slope and cranial level were independent risk factors for non-fusion. The adjacent segment degeneration (ASD) and subsidence rates were comparable between the two levels.

CONCLUSION

The caudal level had a slower fusion process than the cranial level. A higher preoperative segment slope was a risk factor for fusion. However, the subsidence and ASD rate were comparable between the caudal and cranial levels in the two-level ACDF.

Smoking Is an Independent Risk Factor for 90-Day Readmission and Reoperation Following Posterior Cervical Decompression and Fusion

BACKGROUND

Posterior cervical decompression and fusion (PCF) is a common procedure used to treat various cervical spine pathologies, but the 90-d outcomes following PCF surgery continue to be incompletely defined.

OBJECTIVE

To identify risk factors associated with 90-d readmission and reoperation following PCF surgery.

METHODS

Adults undergoing PCF from 2012 to 2020 were identified. Demographic and radiographic data, surgical characteristics, and 90-d outcomes were collected. Univariate analysis was performed using Student's t-test, chi square, and Fisher exact tests as appropriate. Multivariable logistic regression models with lasso penalty were used to analyze various risk factors.

RESULTS

A total of 259 patients were included. The 90-d readmission and reoperation rates were 9.3% and 4.6%, respectively. The most common reason for readmission was surgical site infection (SSI) (33.3%) followed by new neurological deficits (16.7%). Patients who smoked tobacco had 3-fold greater odds of readmission compared to nonsmokers (odds ratio [OR]: 3.48; 95% CI 1.87-6.67; P = .0001). Likewise, the most common reason for reoperation was SSI (33.3%) followed by seroma and implant failure (25.0% each). Smoking was also an independent risk factor for reoperation, associated with nearly 4-fold greater odds of return to the operating room (OR: 3.53; 95% CI 1.53-8.57; P = .003).

CONCLUSION

Smoking is a significant predictor of 90-d readmission and reoperation in patients undergoing PCF surgery. Smoking cessation should be strongly considered preoperatively in elective PCF cases to minimize the risk of 90-d readmission and reoperation.

Diabetes Mellitus Does Not Impact Achievement of a Minimum Clinically Important Difference Following Anterior Cervical Discectomy and Fusion

BACKGROUND

Diabetes mellitus (DM) has been identified as a risk factor for poorer outcomes following anterior cervical discectomy and fusion (ACDF). This study aims to evaluate the impact DM has on achievement of MCID (minimum clinically important difference) following ACDF.

METHODS

A surgical database was reviewed for patients who underwent primary, single-level ACDF procedures with posterior instrumentation. Visual analog scales (VAS) Arm and Neck, Neck Disability Index (NDI), and Patient-Reported Outcomes Measurement Information System (PROMIS) and 12-item Short Form (SF-12) scores for physical function (PF) were recorded. MCID achievement was calculated using pre-established values from the literature. Intergroup differences in demographic, perioperative characteristics, mean outcome scores and rates of MCID achievement were calculated.

RESULTS

There were 43 patients with diabetes and 320 patients without diabetes. DM status was significantly associated with age, ethnicity, hypertension, American Society of Anesthesiologists physical classification score, Charlson Comorbidity Index, and insurance type (all P ≤ 0.041). Postoperative length of stay was significantly greater for the DM group (P = 0.011). Mean VAS Arm and NDI differed at 6 months (P ≤ 0.049, both) and PROMIS-PF differed from 6 weeks through 6 months (P ≤ 0.039, all). Patients without diabetes significantly improved in all PROMs by 1 year postoperatively (P < 0.01, all). Patients with diabetes significantly improved in VAS Neck and Arm, SF-12 physical component score, and PROMIS-PF by 1 year (all P ≤ 0.013) but NDI significantly improved only at 12 weeks (P = 0.038). Intergroup differences for MCID achievement were demonstrated at 6 months for NDI and SF-12 physical component score (P ≤ 0.008).

CONCLUSIONS

Although moderate intergroup differences in MCID achievement were demonstrated, the results of this study suggest that patients may realize similar benefits of ACDF surgery regardless of DM status.

Anterior Cervical Arthrodesis With Polyetheretherketone Spacers: What is the Role of the Grafting Material?

STUDY DESIGN

This was a retrospective study of 2 surgeons' use of a single polyetheretherketone (PEEK) device.

OBJECTIVE

Our objective was to investigate the fusion adjunct placed within PEEK devices to examine the likelihood of an arthrodesis, regardless of the PEEK interbody device itself.

SUMMARY OF BACKGROUND DATA

The effectiveness of PEEK interbody devices in anterior cervical arthrodesis has been questioned.

METHODS

The authors retrospectively reviewed the results of 121 patients with demineralized bone matrix (DBM) and 96 with local autograft bone placed within identical PEEK devices for anterior cervical arthrodesis (from 2011 to 2018); 1 surgeon used DBM and another local autograft bone. Arthrodesis was determined independently by a surgeon and 2 blinded neuroradiologists.

RESULTS

For DBM versus autograft; mean age was 60 versus 61 years, smoking status 42.1% versus 31%, diabetes mellitus 18.2% versus 28%, mean body mass index 31 versus 30, and follow up averaged 17 months in both groups. For DBM versus autograft; a radiographic arthrodesis was observed in 22.3% versus 76% of patients. Refusion at the index level was required in 5.8% of the DBM and 0% of the autograft patients.

CONCLUSIONS

A PEEK interbody device filled with local autograft resulted in a higher radiographic fusion rate and a lower need for reoperation at the index level than an identical device filled with DBM. Caution is warranted in assigning fusion failure to the PEEK device alone in anterior cervical discectomy and fusion surgery.

Does screw length for primary two-level ACDF influence pseudarthrosis risk?

BACKGROUND CONTEXT

Pseudarthrosis remains a major complication for patients undergoing anterior cervical discectomy and fusion (ACDF; 0%-15% at 1-year follow-up). Potentially modifiable risk factors are known in literature, such as smoking and osteoporosis. Biomechanical studies suggest that plates with locking screws can enhance the fixation rigidity and pull-out strength. Although longer screws are known to be correlated with increased pull-out strength, deeper screw depths can increase the risk for intraoperative complications. An important factor that has yet to be studied is the minimum screw length relative to the diameter of the vertebral body (VB) necessary to achieve successful fusion. In this study, we hypothesize that screws with shorter depths relative to the VB will increase the risk for radiographic pseudarthrosis and result in poor patient reported outcomes (PROs).

PURPOSE

To examine the impact of ACDF screw length on pseudarthrosis risk.

STUDY DESIGN

A review of prospectively collected data.

PATIENT SAMPLE

A total of 85 patients were included in this study. The mean age ±standard deviation was 58.9±10.3 and 42.4% of patients were female. The mean follow-up was 21.6±8.3 months.

OUTCOME MEASURES

The neck disability index (NDI) was used to assess PROs up to 2-years after surgery. For each ACDF level, the screw length and VB% (screw length divided by the anterior-posterior VB diameter) were measured. Radiographic pseudarthrosis (interspinous motion [ISM] ≥1 mm) was recorded at 6-weeks, 6-months, and 1-year for each patient. The positive and negative predictive values (PPV, NPV) for ISM ≥ 1mm were measured for different VB% thresholds. A VB% of <75% was found to have the highest PPV (93%) and NPV (70%) for radiographic pseudarthrosis. This threshold of <75% was then assessed in our bivariate and multivariate analyses.

METHODS

We reviewed a database (2015-2018) of adult (≥18 years old) patients who underwent a primary two-level ACDF with or without corpectomy. All ACDF constructs involved fixed angle screws. The minimum follow-up period was 1 year. Multivariate analyses were performed to determine if screw VB% was an independent risk factor for radiographic pseudarthrosis.

RESULTS

By 1-year, overall fusion success was achieved in 92.9% of patients. The 1-year revision rate was 4.7%. Patients with any screw VB% <75% had substantially worse fusion success (64.3%) than those who did not (98.6%) at 1-year. The VB% <75% increased the risk for radiographic pseudarthrosis at every follow up period. In comparison to other time-points, patients with radiographic pseudarthrosis at 6 weeks had significantly worse NDI scores by 2-years (p=.047). The independent risk factors for radiographic pseudarthrosis at 6-weeks included any screw VB% <75% (OR 77, p<.001), prior/current smoker (OR 6.8, p=.024), and corpectomy (OR 0.1, p=.010). Patients with ISM≥1 mm had a higher rate of revision surgery at 1-year (5.9% vs. 3.9%), but this was not statistically significant (p=.656).

CONCLUSIONS

In primary two-level ACDF, VB% <75% is significantly associated with increased ISM (≥1 mm) at all time points for this study. As an intraoperative guide, spine surgeons can use the screw VB% threshold of <75% to avoid unnecessarily short screws. This threshold can be easily measured pre- and intraoperatively, and has been found to be strongly correlated to radiographic pseudarthrosis in the early postoperative period.

Impact of Diabetes Mellitus Following Tonsillectomy in Adults: A National Surgical Quality Improvement Program Analysis

OBJECTIVES

To identify 30-day complication rates specific to patients with diabetes mellitus following tonsillectomy.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients undergoing tonsillectomy between 2005 and 2018. Patients were stratified into 3 cohorts: insulin-dependent diabetes mellitus (IDDM), non-insulin-dependent diabetes mellitus (NIDDM), and non-diabetes mellitus (NODM). Coarsened-exact-matching was utilized to account for baseline differences between cohorts. Outcomes studied included post-operate complications, prolonged hospitalization, and unplanned readmissions.

RESULTS

A total of 986 DM and 26 774 NODM patients were included, and the mean age of patients undergoing tonsillectomy was 29.5 ± 11.6 and 28.7 ± 11.0 years, respectively. The majority of patients were female (70.5% for both DM and NODM cohorts) and White/Caucasian (89.2% vs 89.3%). Among patients undergoing tonsillectomy, a greater proportion of DM patients experienced an operative time greater than or equal to the 75th percentile (35 minutes; 25.9% vs 22.8%, P = .024), overall morbidity (12.6% vs 5.4%, P < .001), pneumonia (0.6% vs 0.2%, P = .036), and reoperation (10.2% vs 3.5% P < .001) in comparison to NODM patients. In an analysis between IDDM (n = 379) and NIDDM (n = 211) patients, IDDM patients were at an increased risk for prolonged hospitalization (1.4% vs 0.0%, P = .045), pneumonia (5.2% vs 0.5%, P < .001), urinary tract infections (3.3% vs 0.3% P = .004), major complications (15.6% vs 7.7%, P = .002), minor complications (19.9% vs 8.2%, P < .001), and overall complications (10.0% vs 1.3%, P < .001).

CONCLUSION

DM patients are at a heightened risk for complications following tonsillectomy. Standardized protocols, careful pre-operative planning, and stringent glycemic management may help optimize patient outcomes.

Complications of anterior cervical spine surgery: a systematic review of the literature

The anterior approach to the cervical spine is commonly utilized for a variety of degenerative, traumatic, neoplastic, and infectious indications. While many potential complications overlap with those of the posterior approach, the distinct anatomy of the anterior neck also presents a unique set of hazards. We performed a systematic review of the literature to assess the etiology, presentation, natural history, and management of these complications. Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a PubMed search was conducted to evaluate clinical studies and case reports of patients who suffered a complication of anterior cervical spine surgery. The search specifically included articles concerning adult human subjects, written in the English language, and published from 1989 to 2019. The PubMed search yielded 240 articles meeting our criteria. The overall rates of complications were as follows: dysphagia 5.3%, esophageal perforation 0.2%, recurrent laryngeal nerve palsy 1.3%, infection 1.2%, adjacent segment disease 8.1%, pseudarthrosis 2.0%, graft or hardware failure 2.1%, cerebrospinal fluid leak 0.5%, hematoma 1.0%, Horner syndrome 0.4%, C5 palsy 3.0%, vertebral artery injury 0.4%, and new or worsening neurological deficit 0.5%. Morbidity rates in anterior cervical spine surgery are low. Nevertheless, the unique anatomy of the anterior neck presents a wide variety of potential complications involving vascular, aerodigestive, neural, and osseous structures.

Retrospective Data Analysis and Literature Review for a Development of Enhanced Recovery after Surgery Pathway for Anterior Cervical Discectomy and Fusion

Objective

While enhanced recovery after surgery (ERAS) protocols are associated with shorter length of stay and improved outcomes in multiple surgical specialties, its application to spine surgery has been limited. Anterior cervical discectomy and fusion (ACDF) is a common spinal procedure with a relative efficacy and safety profile that makes it suitable for the application of ERAS principles. Reviewing our outcomes and practice and incorporating evidence-based clinical studies, we propose the development of an ERAS pathway for ACDF.

Methods

This is a retrospective review of ACDF cases performed at a single institution by a single surgeon from 2014 to 2017. Primary outcome measures included length of stay, complications, and 30-day readmission rates. The 1- and 2-level and the 3- and 4-level groups were also each consolidated into a single cohort for comparison. A comprehensive review of evidence-based literature pertaining to ACDF was then performed. Best-practice recommendations derived from the literature were incorporated into the proposed ERAS protocol.

Results

In this series of 75 1-level, 77 2-level, 44 3-level and 20 4-level ACDF procedures, the average surgical time (minutes) was 68, 90, 118 and 141; length of stay (days) was 1, 1, 1.4, and 1.7; drain usage (%) was 1.3, 2.6, 13.6 and 10; and 30-day readmission rates (%) were 2.7, 3.9, 4.5, and 15, respectively. Combining the 1- and 2-level as a single group and 3- and 4-level as another cohort, the 3- and 4-level cohort had a significantly higher rate of drain usage and estimated blood loss (EBL) but there was not a difference in length-of-stay, complications or 30-day readmission rates.

Conclusions

Given the relative equivalent safety profile between 1- and 2-level as compared to 3- and 4-level ACDF, the proposed ERAS pathway can be applied to all patients, and not just restricted to 1-level or 2-level ACDF. Taking into account feasibility parameters as deduced from a review of institutional outcomes, this pathway can streamline same-day discharge and improve the patient experience. Its success will be predicated on an iterative improvement process deriving from optimal prospective outcome measurements.

Preoperative Narcotic Use, Impaired Ambulation Status, and Increased Intraoperative Blood Loss Are Independent Risk Factors for Complications Following Posterior Cervical Laminectomy and Fusion Surgery

OBJECTIVE

This retrospective cohort study seeks to identify risk factors associated with complications following posterior cervical laminectomy and fusion (PCLF) surgery.

METHODS

Adults undergoing PCLF from 2012 through 2018 at a single center were identified. Demographic and radiographic data, surgical characteristics, and complication rates were compared. Multivariate logistic regression models identified independent predictors of complications following surgery.

RESULTS

A total of 196 patients met the inclusion criteria and were included in the study. The medical, surgical, and overall complication rates were 10.2%, 23.0%, and 29.1% respectively. Risk factors associated with medical complications in multivariate analysis included impaired ambulation status (odds ratio [OR], 2.27; p=0.02) and estimated blood loss over 500 mL (OR, 3.67; p=0.02). Multivariate analysis revealed preoperative narcotic use (OR, 2.43; p=0.02) and operative time (OR, 1.005; p=0.03) as risk factors for surgical complication, whereas antidepressant use was a protective factor (OR, 0.21; p=0.01). Overall complication was associated with preoperative narcotic use (OR, 1.97; p=0.04) and higher intraoperative blood loss (OR, 1.0007; p=0.03).

CONCLUSION

Preoperative narcotic use and estimated blood loss predicted the incidence of complications following PCLF for CSM. Ambulation status was a significant predictor of the development of a medical complication specifically. These results may help surgeons in counseling patients who may be at increased risk of complication following surgery.

Does the Day of the Week Affect Length of Stay and Hospital Charges Following Anterior Cervical Discectomy and Fusion?

Background

To reduce the economic impact of excessive costs, risk factors for increased length of stay (LOS) must be identified. Previous literature has demonstrated that surgeries later in the week can affect the LOS and costs following joint arthroplasty. However, few investigations regarding the day of surgery have been performed in the spine literature. The present study attempts to identify the association between day of surgery on LOS and hospital charges following anterior cervical discectomy and fusion (ACDF) procedures.

Methods

A prospectively maintained surgical database of primary, level 1-2 ACDF patients between 2008 and 2015 was retrospectively reviewed. Patients were stratified by surgery day: early week (Tuesday) or late week (Friday) ACDF. Differences in patient demographics and preoperative characteristics were compared between cohorts using chi-square analysis or Student t test for categorical and continuous variables, respectively. Direct hospital costs were obtained using hospital charges for each procedure and subsequent care prior to discharge. Associations between date of surgery and costs were assessed using multivariate linear regression controlled for.

Results

Two hundred and ninety-five patients were included in the analysis. One hundred and fifty-three patients underwent early week ACDF, and 142 underwent late week ACDF. Surgery day cohorts reported similar baseline characteristics. There were no differences in operative characteristics or hospital LOS between cohorts. Additionally, no differences in total or subcategorical hospital costs were identified between surgery day cohorts.

Conclusions

Patients undergoing ACDF later in the week exhibit similar LOS and hospital costs compared to those undergoing ACDF early in the week. These results suggest that outpatient procedures with short postoperative stays are likely not affected by the changes in hospital work efficiency that occur during the transition to the weekend. As such, hospitals should not restrict outpatient procedures to specific days of the week.

Level of Evidence

3.

Age Is a Risk Factor for Postoperative Complications Following Excisional Laminectomy for Intradural Extramedullary Spinal Tumors

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

The incidence of intradural extramedullary (IDEM) spinal tumors is increasing. Excisional laminectomy for removal and decompression is the standard of care, but complications associated with patient age are unreported in the literature. Our objective is to identify if age is a risk factor for postoperative complications after excisional laminectomy of IDEM spinal tumors.

METHODS

A retrospective analysis was performed on the 2011 to 2014 ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database for patients undergoing excisional laminectomy of IDEM spinal tumors. Age groups were determined by interquartile analysis. Chi-squared tests, t tests, and multivariate logistic regression models were employed to identify independent risk factors. Institutional review board approval was not needed.

RESULTS

A total of 1368 patients met the inclusion criteria for the study. Group 1 (age ≤ 44) contained 372 patients, group 2 (age 45-54) contained 314 patients, group 3 (age 55-66) contained 364 patients, and group 4 (age > 66) contained 318 patients. The univariate analysis showed that mortality and unplanned readmission were highest among patients in group 4 (1.26%, P = .011, and 10.00%, P = .039, respectively). Postoperative wound complications were highest among patients in group 1 (2.15%, P = .009), and postoperative venous thromboembolism and cardiac complications were highest among patients in group 3 (4.4%, P = .007, and 1.10%, P = .032, respectively). Multivariate logistic regression revealed that elderly age was an independent risk factor for postoperative venous thromboembolism (group 3 vs group 1; odds ratio = 6.739, confidence interval = 1.522-29.831, P = .012).

CONCLUSIONS

This analysis revealed that increased age is an independent risk factor for postoperative venous thromboembolism in patients undergoing excisional laminectomy for IDEM spinal tumors.

Comparative Study Between M6-C and Mobi-C Cervical Artificial Disc Replacement: Biomechanical Outcomes and Comparison with Normative Data

OBJECTIVE

Cervical spondylosis affects a huge proportion of the middle-aged population. Degenerative changes can occur in multiple regions of the cervical spine typically affecting the joints, intervertebral discs and endplates. These changes lead to compression of adjacent nervous structures, which results in radiculopathic and myelopathic pain. Various treatment modalities are currently available with non-surgical approaches the initial go to if there is no symptomatic cord compression. Anterior cervical discectomy and fusion, or arthroplasty are the two common surgical approaches if non-surgical treatments fail to relieve symptoms of the patients or there are signs of central cord compression. However, studies have shown that there is an increased risk of adjacent segment disease related to fusion. Cervical disc arthroplasty aims to restore normal range of motion (ROM) in patients with pain and disability due to degenerative disc disease resistant to conservative care. Two common disc prostheses used include M6-C and Mobi-C. Both prostheses comprise a mobile polymer segment sandwiched between two metal endplates with mechanisms resembling an actual intervertebral disc. This study aims to compare the kinematics associated with these prostheses, against the normal range of motion in the non-degenerative population.

METHOD

Patients who underwent M6-C or Mobi-C disc replacements by the senior author from 2012 to 2015 were identified at a single tertiary institution. Routine 3-month postoperative lateral radiographs were analyzed for flexion and extension ROM angles at the involved vertebral level by two independent authors. Data was compared to previous published studies investigating cervical spine ROM of asymptomatic patients.

RESULTS

There was no statistical significance in the difference of overall flexion range between M6-C and Mobi-C prostheses. However, overall range of extension of Mobi-C was greater compared to M6-C (P = 0.028). At C_5-6 , the range of flexion for both implants were similar but lesser compared to asymptomatic patients (P < 0.001). Range of extension was greater in the Mobi-C group (14.2° ± 5.1°) compared to the M6-C (7.3° ± 4.6°) (P = 0.0009). At C_6-7 , there were no statistical differences in both range of flexion and extension between the two prostheses and asymptomatic patients (P > 0.05).

CONCLUSION

The early results regarding restoration of ROM following cervical arthroplasty using either M6-C or Mobi-C prosthesis are encouraging. Long-term follow-up studies are necessary to observe the change in ROM over time with physiological loading and wear patterns.

Age Stratification of 30-Day Postoperative Outcomes Following Excisional Laminectomy for Extradural Cervical and Thoracic Tumors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To evaluate age as an independent predictive factor for perioperative morbidity and mortality in patients undergoing surgical decompression for metastatic cervical and thoracic spinal tumors using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2011 to 2014.

METHODS

We identified 1673 adult patients undergoing excisional laminectomy of cervical and thoracic extradural tumors. Patients were stratified into quartiles based on age, with Q1 including patients aged 18 to 49 years, Q2 including patients aged 50 to 60 years, Q3 including patients aged 61 to 69 years, and Q4 including patients ≥70 years. Univariate and multivariate regression analyses were performed to examine the association between age and 30-day perioperative morbidity and mortality.

RESULTS

Age was an independent risk factor for 30-day venous thromboembolism (VTE) and reoperation. Patients in Q3 for age had nearly a 4 times increased risk of VTE than patients in Q1 (odds ratio [OR] 3.97; 95% CI 1.91-8.25; P < .001). However, there was no significant difference in VTE between patients in Q4 and Q1 (P = .069). Patients in Q2 (OR 1.99; 95% CI 1.06-3.74; P = .032) and Q4 (OR 2.18; 95% CI 1.06-4.52; P = .036) for age had a 2 times increased risk of reoperation compared with patients in Q1.

CONCLUSIONS

Age was an independent predictive factor for perioperative VTE and reoperation, but there was no clear age-dependent relationship between increasing age and the risk of these perioperative complications.

General Health Adverse Events Within 30 Days Following Anterior Cervical Discectomy and Fusion in US Patients: A Comparison of Spine Surgeons' Perceptions and Reported Data for Rates and Risk Factors

STUDY DESIGN

Survey study and retrospective review of prospective data.

OBJECTIVES

To contrast surgeons' perceptions and reported national data regarding the rates of postoperative adverse events following anterior cervical discectomy and fusion (ACDF) and to assess the accuracy of surgeons in predicting the impact of patient factors on such outcomes.

METHODS

A survey investigating perceived rates of perioperative complications and the perceived effect of patient risk factors on the occurrence of complications following ACDF was distributed to spine surgeons at the Cervical Spine Research Society (CSRS) 2015 Annual Meeting. The equivalent reported rates of adverse events and impacts of patient risk factors on such complications were assessed in patients undergoing elective ACDF from the National Surgical Quality Improvement Program (NSQIP).

RESULTS

There were 110 completed surveys from attending physicians at CSRS (response rate = 44%). There were 18 019 patients who met inclusion criteria in NSQIP years 2011 to 2014. The rates of 11 out of 17 (65%) postoperative adverse events were mildly overestimated by surgeons responding to the CSRS questionnaire in comparison to reported NSQIP data (overestimates ranged from 0.24% to 1.50%). The rates of 2 out of 17 (12%) postoperative adverse events were mildly underestimated by surgeons (range = 0.08% to 1.2%). The impacts of 5 out of 10 (50%) patient factors were overestimated by surgeons (range relative risk = 0.56 to 1.48).

CONCLUSIONS

Surgeon estimates of risk factors for and rates of adverse events following ACDF procedures were reasonably nearer to national data. Despite an overall tendency toward overestimation, surgeons' assessments are roughly appropriate for surgical planning, expectation setting, and quality improvement initiatives.

Retrospective single-surgeon study of 1123 consecutive cases of anterior cervical discectomy and fusion: a comparison of clinical outcome parameters, complication rates, and costs between outpatient and inpatient surgery groups, with a literature review

OBJECTIVE Outpatient anterior cervical discectomy and fusion (ACDF) is becoming more common and has been reported to offer advantages over inpatient procedures, including reducing nosocomial infections and costs, as well as improving patient satisfaction. The goal of this retrospective study was to evaluate and compare outcome parameters, complication rates, and costs between inpatient and outpatient ACDF cases performed by 1 surgeon at a single institution. METHODS In a retrospective study, the records of all patients who had undergone first-time ACDF performed by a single surgeon in the period from June 1, 2003, to January 31, 2016, were reviewed. Patients were categorized into 2 groups: those who had undergone ACDF as outpatients in a same-day surgical center and those who had undergone surgery in the hospital with a minimum 1-night stay. Outcomes for all patients were evaluated with respect to the following parameters: age, sex, length of stay, preoperative and postoperative pain (self-reported questionnaires), number of levels fused, fusion, and complications, as well as the presence of risk factors, such as an increased body mass index, smoking, and diabetes mellitus. RESULTS In total, 1123 patients were operated on, 485 (43%) men and 638 (57%) women, whose mean age was 50 years. The mean follow-up time was 25 months. Overall, 40.5% underwent 1-level surgery, 34.3% 2-level, 21.9% 3-level, and 3.2% 4-level. Only 5 patients had nonunion of vertebrae; thus, the fusion rate was 99.6%. Complications occurred in 40 patients (3.6%), with 9 having significant complications (0.8%). Five hundred sixty patients (49.9%) had same-day surgery, and 563 patients (50.1%) stayed overnight in the hospital. The inpatients were older, were more commonly male, and had a higher rate of diabetes. Smoking status did not influence the length of stay. Both groups had a statistically significant reduction in pain (expressed as a visual analog scale score) postoperatively with no significant difference between the groups. One- and 2-level surgeries were done significantly more often in the outpatient setting (p < 0.001). The complication rate was 4.1% in the outpatient group and 3.0% in the inpatient group; there was no statistically significant difference between the 2 groups (p = 0.339). Significantly more complications occurred with 3- and 4-level surgeries than with 1- and 2-level procedures (p < 0.001, chi-square test). The overall average inpatient cost for commercial insurance carriers was 26% higher than those for outpatient surgery. CONCLUSIONS Anterior cervical discectomy and fusion is safe for patients undergoing 1- or 2-level surgery, with a very significant rate of pain reduction and fusion and a low complication rate in both clinical settings. Outpatient and inpatient groups undergoing 3- or 4-level surgery had an increased risk of complications (compared with those undergoing 1- or 2-level surgery), with a negligible difference between the 2 groups. This finding suggests that these procedures can also be included as standard outpatient surgery. Comparable outcome parameters and the same complication rates between inpatient and outpatient groups support both operative environments.

Nutritional Status as an Adjunct Risk Factor for Early Postoperative Complications Following Posterior Cervical Fusion

STUDY DESIGN

Retrospective study on prospectively collected data.

OBJECTIVE

The aim of this study was to study the impact of nutritional status, as measured by serum albumin level, on patient outcomes following posterior cervical fusion (PCF) surgery.

SUMMARY OF BACKGROUND DATA

Malnutrition is a potential modifiable risk factor that has garnered an increasing amount of attention within orthopedics in recent years. There is evidence to suggest the role of nutritional status in lumbar and ACDF surgery, yet the data for PCF are still lacking.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) was queried by current procedure terminology (CPT) from 2010 to 2014. Bivariate analyses were performed to compare the preoperative characteristics between those with normal albumin and hypoalbuminemia. Postoperative complications and outcomes were similarly analyzed for those with and without low albumin levels. Stepwise multivariate logistic regression models were employed to determine whether hypoalbuminemia was an independent risk factor for short-term patient outcomes and complications.

RESULTS

There were 1573 cases with measured albumin levels (42.4%). The mean (standard deviation) serum albumin level was 3.9 (0.6). Among these patients, 265 (16.8%) cases had hypoalbuminemia. The adjusted analyses demonstrated that patients with hypoalbuminemia had a significantly higher risk for length of stay >5 days (odds ratio [OR] = 3.8; 95% confidence interval [CI] = 2.8-5.1; P < 0.0001). In addition, hypoalbuminemia was an independent risk factor for any complications (OR = 2.7; 95% CI = 1.9-3.7; P < 0.0001), pulmonary complications (OR = 2.3; 95% CI = 1.2-4.5; P = 0.010), intra/postoperative blood transfusions (OR = 3.2; 95% CI = 2.1-4.9; P < 0.0001), sepsis (OR = 4.0; 95% CI = 1.7-9.2; P = 0.001), and venous thromboemoblism (OR = 3.6; 95% CI = 1.5-8.5; P = 0.004).

CONCLUSION

These findings implicate that a baseline serum albumin <3.5 g/dL may serve as a valuable prognostic measure for the development of several complications following PCF surgery.

LEVEL OF EVIDENCE

3.

Predictors of complications and readmission following spinal stereotactic radiosurgery

AIM

to identify preoperative factors associated with morbidity/mortality, hospital length of stay (LOS), 30-day readmission and operation rates following spinal stereotactic radiosurgery (SRS) for spinal tumors.

METHODS

The American College of Surgeons National Quality Improvement Program was queried from 2012 to 2014 to identify patients undergoing SRS for spinal tumors. Logistic regression was performed to identify predictors.

RESULTS

2714 patients were identified; 6.8% had major morbidity or mortality, 6.9% were readmitted within 30 days and 4.3% had a subsequent operation within 30 days. Age, BMI and American Society of Anesthesiologist (ASA) class were predictive of LOS. Major morbidity was predicted by age >80, BMI >35, high ASA, pretreatment functional dependence and baseline comorbidities. Predictors of operation within 30 days included preoperative steroid use, renal failure, BMI >35 and if the treatment was nonelective.

DISCUSSION

4-7% of patients undergoing SRS for spinal tumors have morbidity following the procedure. Factors predictive of morbidity, LOS, and subsequent operation included age, BMI, baseline comorbidities and functional status.

CONCLUSION

Identification of preoperative patient-specific factors that are predictive of post-treatment outcome will aid in patient selection and patient counseling leading to greater patient satisfaction and hospital efficiency.

Predominantly negative impact of diabetes on spinal surgery: A review and recommendation for better preoperative screening

BACKGROUND

For patients undergoing spine surgery, the literature attributes significant increased perioperative risks/adverse events (AE) complications, longer length of stay (LOS), and higher 30-day readmission/reoperation rates to those with diabetes. Diabetics are often divided into those with insulin dependent diabetes (IDDM), and non-insulin dependent diabetes (NIDD). However, other series also compare those with uncontrolled diabetes (UCDM) vs. those with controlled DM (CDM).

METHODS

We found a marked variation in the size and quality of studies identified in PubMed regarding the impact of diabetes on spinal surgery (e.g., focusing on complications, AE, outcomes, morbidity, and mortality).

RESULTS

Of the 197,461 lumbar fusions in one NIS (Nationwide Inpatient Sample 1988-2003), 11,000 (5.6%) diabetics (DM) had higher infection rates, transfusion rates, more pneumonias, higher in-hospital mortality rates, greater costs, and longer LOS than those undergoing similar procedures without DM. For 3726 ACS-NSQIP patients undergoing anterior cervical fusions, 270 NIDDM had more urinary tract infections and returns to the operating room; the 171 IDDM required more reoperations, 30 day readmission, and longer LOS (by 5 days) vs. 3285 non DM. Of the 5627 patients undergoing posterior cervical fusions (ACS-NSQIP), 2029 (36.1%) had AE directly related to DM. In another NSQUIP study of 51277 patients undergoing lumbar spine surgery, IDDM and NIDDM demonstrated longer LOS, plus IDDM showed more surgical AE and 30 day readmissions vs. those with no DM.

CONCLUSIONS

Patients with IDDM or NIDDM undergoing spine surgery exhibited more perioperative complications/AE/morbidity, longer LOS, and higher readmission/reoperation rates vs. non DM.

Relationship between depression and clinical outcome following anterior cervical discectomy and fusion

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure for patients with symptomatic degenerative conditions of the cervical spine. The objective is to assess the impact of preoperative depression and other baseline characteristics on patient reported clinical outcomes following ACDF surgery based on the experience at our institution.

METHODS

This was a retrospective cohort study of some patients undergoing ACDF at a single institution from 2012 to 2014. Ninety-three patients that underwent an ACDF procedure were included. The primary outcome measure was post-operative Nurick score.

RESULTS

Sixteen (17.2%) patients had a formal diagnosis of depression compared to 77 (82.8%) patients without depression. On univariate analysis, patients with depression had statistically significantly higher Nurick scores compared to patients without depression after surgery (coefficient =0.55, 95% CI: 0.21-0.90, P=0.002). On multivariate analysis, there was a trend toward higher postoperative Nurick scores in patients that had depression (coefficient =0.31, 95% CI: -0.01-0.63, P=0.057).

CONCLUSIONS

This small retrospective study reveals an inverse relationship between preoperative depression and functional outcome. Further research should be performed to investigate this relationship and to investigate if treating depression can improve postoperative outcomes.