Poorer Fusion Outcomes in Diabetic Cervical Spondylotic Myelopathy Patients Undergoing Single-level Anterior Cervical Discectomy and Fusion Does Not Compromise Functional Outcomes and Quality of Life

Insulin dependence negatively impacts outcomes in anterior cervical discectomy with fusions: a ten-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 post-operative 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) non-insulin-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 post-operative 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.

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.

The Effect of Diabetes on Complications after Spinal Fusion: A Systematic Review and Meta-Analysis

OBJECTIVE

Spinal fusion procedures are used to treat a wide variety of spinal pathologies. Diabetes mellitus (DM) has been shown to be a significant risk factor for several complications following these procedures in previous studies. To the authors' knowledge, this is the first systematic review and meta-analysis elucidating the relationship between DM and complications occurring after spinal fusion procedures.

METHODS

Systematic literature searches of PubMed and EMBASE were performed from their inception to October 1, 2022, to identify studies that directly compared postfusion complications in patients with and without DM. Studies met the prespecified inclusion criteria if they reported the following data for patients with and without DM: (1) demographics; (2) postspinal fusion complication rates; and (3) postoperative clinical outcomes. The included studies were then pooled and analyzed.

RESULTS

Twenty-eight studies, with a cumulative total of 18,853 patients (2695 diabetic patients), were identified that met the inclusion criteria. Analysis showed that diabetic patients had significantly higher rates of total number of postoperative complications (odds ratio [OR] = 1.33; 95% confidence interval [CI] = 1.12-1.58; P = 0.001), postoperative pulmonary complications (OR=2.01; 95%CI=1.31-3.08; P = 0.001), postoperative renal complications (OR=2.20; 95%CI=1.27-3.80; P = 0.005), surgical site infection (OR=2.65; 95%CI=2.19-3.20; P < 0.001), and prolonged hospital stay (OR=1.67; 95%CI=1.47-1.90; P < 0.001).

CONCLUSIONS

Patients with DM had a significantly higher risk of developing complications after spinal fusion, particularly pulmonary and renal complications, in addition to surgical site infections and had a longer length of stay. These findings are important for informed discussions of surgical risks with patients and families before surgery.

The significance of metabolic disease in degenerative cervical myelopathy: a systematic review

Introduction

Degenerative cervical myelopathy (DCM) is a form of chronic spinal cord injury, with a natural history of potential for progression over time. Whilst driven by mechanical stress on the spinal cord from degenerative and congenital pathology, the neurological phenotype of DCM is likely to be modified by multiple systemic factors. The role of metabolic factors is therefore of interest, particularly given that ischaemia is considered a key pathological mechanism of spinal cord injury. The objective was therefore to synthesise current evidence on the effect of metabolism on DCM susceptibility, severity, and surgical outcomes.

Methods

A systematic review in MEDLINE and Embase was conducted following PRISMA guidelines. Full-text papers in English, with a focus on DCM and metabolism, including diabetes, cardiovascular disease, anaemia, and lipid profile, were eligible for inclusion. Risk of methodological bias was assessed using the Joanna Briggs Institute (JBI) critical assessment tools. Quality assessments were performed using the GRADE assessment tool. Patient demographics, metabolic factors and the relationships between metabolism and spinal cord disease, spinal column disease and post-operative outcomes were assessed.

Results

In total, 8,523 papers were identified, of which 57 met criteria for inclusion in the final analysis. A total of 91% (52/57) of included papers assessed the effects of diabetes in relation to DCM, of which 85% (44/52) reported an association with poor surgical outcomes; 42% of papers (24/57) discussed the association between cardiovascular health and DCM, of which 88% (21/24) reported a significant association. Overall, DCM patients with diabetes or cardiovascular disease experienced greater perioperative morbidity and poorer neurological recovery. They were also more likely to have comorbidities such as obesity and hyperlipidaemia.

Conclusion

Metabolic factors appear to be associated with surgical outcomes in DCM. However, evidence for a more specific role in DCM susceptibility and severity is uncertain. The pathophysiology and natural history of DCM are critical research priorities; the role of metabolism is therefore a key area for future research focus.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021268814.

Using Piezosurgery in Anterior Cervical Discectomy and Fusion to Treat Complex Cervical Spondylotic Myelopathy Is Safe and Effective

Objective

To investigate the safety and efficacy of piezosurgery in anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM).

Methods

47 patients with complex CSM (cCSM) underwent ACDF surgery from 2014 to 2017. Among these patients, 26 underwent ACDF using piezosurgery (group A) and 21 underwent ACDF by using traditional tools such as high-speed air drill, bone curette, and Kerrison bone punch (group B). Average surgical time, intraoperative blood loss, surgical complications, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, and improvement rate were measured.

Results

Average surgical time and intraoperative blood loss were significantly lower in group A than those in group B (P < 0.01). The incidences of surgical complications were 3.8% and 23.8% in the A and B groups (P < 0.05), respectively. There were no significant differences in JOA scores and improvement rates between data collection periods at preoperative, 3-day postoperative, and 1-year postoperative follow-ups (P > 0.05).

Conclusion

For treating cCSM, both the piezosurgery and traditional tools led to significant neurological improvement. However, the piezosurgery was superior to the traditional tools in terms of surgical time, blood loss, and complication rate. Hence, piezosurgery was a safe and effective adjunct for ACDF treating cCSM.

Determinants of quality of life in degenerative cervical myelopathy: a systematic review

BACKGROUND

Degenerative cervical myelopathy (DCM) is the most common cause of chronic, progressive spinal cord impairment worldwide. Patients experience substantial pain, functional neurological decline and disability. Health-related quality of life (HRQoL) appears to be particularly poor, even when compared to other chronic diseases. However, the determinants of HRQoL are poorly understood. The objective was to perform a systematic review of the determinants of quality of life of people with DCM.

METHODS

A systematic search was conducted in MEDLINE and Embase following PRISMA 2020 guidelines (PROSPERO CRD42018115675). Full-text papers in English, exclusively studying DCM, published before 26 March 2020 were eligible for inclusion and were assessed using the Newcastle-Ottawa Scale and the Cochrane Risk of Bias 2 (RoB 2) tool. Study sample characteristics, patient demographics, cohort type, HRQoL instrument utilised, HRQoL score, and relationships of HRQoL with other variables were qualitatively synthesised.

RESULTS

A total of 1176 papers were identified; 77 papers and 13,572 patients were included in the final analysis. A total of 96% of papers studied surgical cohorts and 86% utilised the 36-Item Short Form Survey (SF-36) as a measure of HRQoL. HRQoL determinants were grouped into nine themes. The most common determinant to be assessed was surgical technique (38/77, 49%) and patient satisfaction and experience of pain (10/77, 13%). HRQoL appeared to improve after surgery. Pain was a negative predictor of HRQoL.

CONCLUSION

Current data on the determinants of HRQoL in DCM are limited, contradictory and heterogeneous. Limitations of this systematic review include lack of distinction between DCM subtypes and heterogenous findings amongst the papers in which HRQoL is measured postoperatively or post-diagnosis. This highlights the need for greater standardisation in DCM research to allow further synthesis. Studies of greater precision are necessary to account for HRQoL being complex, multi-factorial and both time and context dependent.

Optimal hemoglobin A1C target in diabetics undergoing elective cervical spine surgery

BACKGROUND CONTEXT

Diabetes mellitus (DM) is a well-established risk factor for suboptimal outcomes following cervical spine surgery. Hemoglobin A1C (HbA1c), a surrogate for long-term glycemic control, is a valuable assessment tool in diabetic patients.

PURPOSE

In patients undergoing elective cervical spine surgery, we sought to identify optimal HbA1c levels to: (1) maximize 1-year postoperative patient-reported outcomes (PROs), and (2) predict the occurrence of medical and surgical complications.

STUDY DESIGN/SETTING

A retrospective cohort study using prospectively collected data was performed in a single academic center.

PATIENT SAMPLE

Diabetic patients undergoing elective anterior cervical fusion and posterior cervical laminectomy and fusion (PCLF) between October 2010-March 2021 were included.

OUTCOME MEASURES

Primary outcomes included Numeric Rating Scale (NRS)-Neck pain, NRS-Arm pain, and Neck Disability Index (NDI). Secondary outcomes included surgical site infection (SSI), complications, readmissions, and reoperations within 90-days postoperatively.

METHODS

HbA1c, demographic, comorbidity, and perioperative variables were gathered in diabetic patients only. PROs were analyzed as continuous variables and minimum clinically difference (MCID) was set at 30% improvement from baseline.

RESULTS

Of 1992 registry patients undergoing cervical surgery, 408 diabetic patients underwent cervical fusion surgery. Anterior: A total of 259 diabetic patients underwent anterior cervical fusion, 141 of which had an available HbA1c level within one year prior to surgery. Mean age was 55.8±10.1, and mean HbA1c value was 7.2±1.4. HbA1c levels above 6.1 were associated with failure to achieve MCID for NDI (AUC=0.77, 95%CI 0.70-0.84, p<.001), and HbA1c levels above 6.8 may be associated with increased odds of reoperation (AUC=0.61, 95%CI 0.52-0.69, p=.078). Posterior: A total of 149 diabetic patients underwent PCLF, 65 of which had an available HbA1c level within 1 year. Mean age was 63.6±9.2, and mean HbA1c value was 7.2±1.5. Despite a low AUC for NRS-Arm pain and readmission, HbA1c levels above 6.8 may be associated with failure to achieve MCID for NRS-Arm pain (AUC=0.61, 95%CI 0.49-0.73, p=.094), and HbA1c levels above 7.6 may be associated with higher readmission rate (AUC=0.63, 95%CI 0.50-0.75, p=.185).

CONCLUSIONS

In a cohort of diabetic patients undergoing elective cervical spine surgery, HbA1c levels above 6.1 were associated with decreased odds of achieving MCID for NDI in anterior cervical fusion surgery. Though only moderate associations were seen for the select outcomes of reoperation (6.8), readmission (7.6), and MCID for NRS-Arm pain (6.8), preoperative optimization of HbA1c using these levels as benchmarks should be considered to reduce the risk of complications and maximize PROs for patients undergoing elective cervical spine surgery.

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.

Subjective and Objective Quality-of-Life Assessment of Outcome Measures in Cervical Spine Surgery for Degenerative Changes

Cervical spine diskectomy is a commonly used procedure in degenerative disease of cervical spine surgery. However, it is difficult to assess the quality of life after this widely applied and variously modified procedure. This literature review presents cervical diskectomy results, according to various scales and measures in multidirectional surgical strategies. Using relevant databases, we tried to find the best treatment options for degenerative disk disease and the best method of quality-of-life assessment, searching for modalities that may influence the outcome.

Significance of Hospital Size in Outcomes of Single-Level Elective Anterior Cervical Discectomy and Fusion: A Nationwide Readmissions Database Analysis

OBJECTIVE

To elucidate risk factors for 90-day readmission in anterior cervical discectomy and fusion (ACDF) for small, medium, and large hospitals. To assess differences in length of stay, charges, and complication rates across hospitals of different size.

METHODS

A retrospective analysis was performed using elective, single-level ACDF data from 2016 to 2018 in the Healthcare Cost and Utilization Project Nationwide Readmissions Database. Elective single-level ACDF cases were stratified into 3 groups by hospital bed size (small, medium, and large). All-cause complication rates, mean charges, length of stay, and 90-day readmission rates were compared across hospital size. Frequencies of specific comorbidities were compared between readmitted and nonreadmitted patients for each hospital size. Comorbidities significant on univariate analysis were evaluated as independent risk factors for 90-day readmission for each hospital size using multivariate regression.

RESULTS

The overall 90-day readmission rate was 6.43% in 36,794 patients, and the rates for small, medium, and large hospitals were 6.25%, 6.28%, and 6.56%, respectively (P = 0.537). Length of stay increased significantly with hospital size (P < 0.001), and small hospitals had the lowest charges (P < 0.001). Although different independent predictors of 90-day readmission were identified for each hospital size, cardiac arrhythmia, chronic pulmonary disease, neurologic disorders, and rheumatic disease were identified as risk factors for hospitals of all sizes.

CONCLUSIONS

Hospital size is a determining factor for charges and length of stay associated with elective single-level ACDF. Variation in risk factors for readmission exists across hospital size in context of similar 90-day readmission rates.

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.

Comorbidity Influence on Postoperative Outcomes Following Anterior Cervical Discectomy and Fusion

Objective

This study aims to detail the association between comorbidity burden and achieving minimum clinically important difference (MCID) following anterior cervical discectomy and fusion (ACDF).

Methods

A prospective surgical registry was retrospectively reviewed. Patients with missing preoperative Patient-Reported Outcomes Measurement Information System physical function (PROMIS PF) were excluded. Patients were stratified by Charlson Comorbidity Index (CCI): no comorbidities = 0 point; low CCI = 1–2 points; high CCI = ≥ 3 points. Demographic and perioperative characteristics were collected and evaluated for differences. Visual analogue scale (VAS), 12-item Short Form health survey (SF-12), and PROMIS PF were collected pre- and postoperatively and assessed for differences. Differences in achievement of MCID were compared using established values: VAS neck = 2.6, VAS arm = 4.1, NDI = 8.5, SF-12 physical composite score (SF-12 PCS) = 8.1, PROMIS PF = 4.5.

Results

One hundred twenty-five ACDF patients were included: 37 had no comorbidities, 64 with low CCI, and 24 with high CCI. Higher CCI groups were older, nonsmokers, diabetic, arthritic, hypertensive, and had cancer. Multilevel fusions, operative time, length of stay, and later discharge day were associated with high CCI. VAS neck differed preoperatively by group. SF-12 PCS and PROMIS PF were inversely associated with CCI groups. CCI did not impact achievement of MCID for all outcomes. A lower rate of reaching MCID was demonstrated at 3 months for SF-12 PCS.

Conclusion

Regardless of comorbidity burden, patients undergoing ACDF for cervical pathology demonstrated a similar rate of achieving MCID for VAS neck, VAS arm, NDI, and PROMIS PF. Regardless of CCI score, ACDF can have a significant benefit for patients.

Predictors of Outcomes After Single-level Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Myelopathy: A Multivariate Analysis

STUDY DESIGN

This was a retrospective study that was carried out using prospectively collected registry data.

OBJECTIVE

The objective of this study was to identify preoperative predictors of outcomes after anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy.

SUMMARY OF BACKGROUND DATA

Proper patient selection is paramount to achieving good surgical results. Identifying predictors of outcomes may aid surgical decision-making and facilitate counseling of patients to manage expectations.

METHODS

Prospectively collected registry data of 104 patients who underwent single-level ACDF for cervical spondylotic myelopathy were reviewed. Outcomes assessed at 2 years were the presence of residual neck pain/arm pain (AP), and attainment of a minimal clinically important difference (MCID) for Neck Disability Index (NDI), Japanese Orthopaedic Association (JOA) score, and Physical Component Score (PCS) of SF-36, as well as patient satisfaction, fulfilment of expectations, willingness to undergo same surgery again, return to work (RTW), and return to function (RTF). Receiver operating characteristic curves and multivariate stepwise logistical regression were performed to identify independent predictors of each outcome using 22 covariates including demographics, comorbidities, and preoperative disease state.

RESULTS

Lower preoperative NDI was predictive of the absence of residual neck pain/AP at 2 years. Higher preoperative JOA score was predictive of MCID attainment for PCS, satisfaction, expectation fulfilment, willingness to undergo the same surgery for same condition, and RTF. Poorer preoperative scores of NDI, JOA, and PCS were predictors of attaining MCID of the respective scores. Older patients were less likely to attain MCID for JOA. Higher preoperative AP was a risk factor for unsuccessful RTW.

CONCLUSIONS

In general, the preoperative JOA score was the best predictor of outcomes after ACDF. A preoperative JOA cutoff value of 9.25-10.25 predicted satisfaction, expectation fulfilment, willingness to undergo same surgery, and RTF with at least 70% sensitivity and 50% specificity. These findings may aid surgeons in identifying patients at risk of a poor outcome and guide preoperative counseling to establish realistic expectations of the surgical outcome.

LEVEL OF EVIDENCE

Level III-Non-randomized controlled cohort/follow-up study.

Women Do Not Have Poorer Outcomes After Minimally Invasive Lumbar Fusion Surgery: A Five-Year Follow-Up Study

BACKGROUND

Women undergoing lumbar spine surgery report greater preoperative pain and disability and have less improvement after surgery. There is a paucity of literature on sex-related differences after minimally invasive surgery transforaminal lumbar interbody fusion (MIS TLIF) surgery. We aim to determine whether sex influences outcome after MIS TLIF at 5-year midterm follow-up.

METHODS

Prospectively collected registry data for 907 patients who underwent MIS TLIF at a single institution from 2004 to 2013 were reviewed. Of these, 296 patients (94 males and 202 females) were reviewed at 5-year follow-up. All patients were assessed preoperatively and postoperatively at 2 and 5 years. Data recorded included patient demographics, Oswestry Disability Index (ODI), Short-Form 36 Physical and Mental component scores (SF-36 PCS and MCS), and the North American Spine Society lumbar spine outcome assessment instrument.

RESULTS

Females who underwent MIS TLIF were generally younger (females, 52.2 years; males, 56.1 years; P = .04). Females had significantly poorer preoperative ODI (females, 49.5; males, 41.5; P < .001) and SF-36 PCS (females, 31.9; males, 35.6; P < .01) and MCS (females, 44.9; males, 49.2; P < .01) scores. At 2-year and 5-year follow-up, there were no significant differences in ODI, SF-36, and pain scores between sexes. Both groups reported similar proportions that returned to work and returned to function. There were no differences in proportion of patients who were satisfied or had their expectations fulfilled.

CONCLUSIONS

Women who undergo MIS TLIF have poorer preoperative function and quality of life than men. However, women demonstrated greater improvement after surgery, attaining similar clinical outcomes at 5-year follow-up.

LEVEL OF EVIDENCE

3.

Psychological predictors of quality of life after anterior cervical discectomy and fusion for degenerative cervical spine disease

We aimed to identify independent psychological predictors of quality of life (QOL) and functional outcome after anterior cervical discectomy and fusion (ACDF) for degenerative cervical spine disease. We prospectively included patients undergoing ACDF for degenerative cervical disc herniation and stenosis. Patients completed a structured psychological assessment including the Center for Epidemiological Studies Depression Scale (ADS-K), Post-Traumatic Stress Scale-10 (PTSS-10), State Trait Anxiety Inventory-State Anxiety and - Trait Anxiety (STAI-S and STAI-T) and Anxiety Sensitivity Index-3 (ASI-3) before surgery, after 3 and 12 months. Outcome measures included EuroQol-5D (EQ), Short Form-36 (SF-36) and Oswestry Disability Index (ODI) scores. Of 104 included patients who underwent ACDF between March 2013 and November 2017, 92 completed follow-up after 3 and 12 months. The mean Visual Analogue Scale (VAS) scores for neck pain (− 1.4; p < .001) and arm pain (− 1.8; p = .031) significantly decreased by 12 months. QOL scores significantly increased by 3 months (EQ: + 0.2; p < .001; SF-36 PCS: + 6.2; p < .001; SF-36 MCS: + 2.5; p = .044), a benefit which was retained at 12 months. Linear regression analyses identified statistically significant predictors in preoperative ASI-3, SF-36 MCS and STAI-S for postoperative QOL and ODI scores. There is a benefit for patients in terms of quality of life and function after undergoing surgery for degenerative cervical spine disease. With the ASI-3, SF-36 MCS and STAI-S there exist some predictors for postoperative QOL and ODI scores.

Severity of Preoperative Myelopathy Symptoms Affects Patient-reported Outcomes, Satisfaction, and Return to Work After Anterior Cervical Discectomy and Fusion for Degenerative Cervical Myelopathy

STUDY DESIGN

Retrospective review of prospectively-collected registry data.

OBJECTIVE

To compare the patient-reported outcomes, satisfaction, and return to work among a large cohort of patients stratified by preoperative myelopathy severity undergoing Anterior Cervical Discectomy and Fusion (ACDF) for Degenerative Cervical Myelopathy.

SUMMARY OF BACKGROUND DATA

Recent clinical practice guidelines noted a lack of studies stratifying their sample based on preoperative disease severity. The benefits of early surgical intervention for patients with mild myelopathy remain uncertain.

METHODS

A prospectively-maintained registry was retrospectively reviewed for all patients who underwent primary ACDF for Degenerative Cervical Myelopathy. Patients were stratified based on severity of preoperative myelopathy symptoms according to the Japanese Orthopaedic Association (JOA) scale: mild (>13), moderate (9-13), or severe (<9). Patients were prospectively followed for at least 2 years.

RESULTS

In total, 219 patients were included: 74 mild, 94 moderate, and 51 severe cases. The mild group had significantly better Neurogenic Symptoms (NS), Neck Disability Index (NDI), SF-36 Physical (PCS), and Mental Component Summary at baseline (P < 0.05). Neck and arm pain scores were similar at all time points. At 2 years, the severe group still had significantly worse patient-reported outcomes and lower rates of satisfaction, expectation fulfilment and return to work. However, they had significantly greater improvement in JOA, Neurogenic Symptoms, NDI, PCS, and Mental Component Summary, and a larger proportion attained minimal clinically important difference (MCID) for NDI and PCS. All three groups had similar proportions attaining MCID for JOA.

CONCLUSION

Patients with severe myelopathy experienced a greater improvement after ACDF. Although fewer patients attained MCID, early surgical intervention for patients with mild myelopathy should also be considered, as this may allow patients to maintain their higher functional status. They also had high rates of postoperative satisfaction and return to work. The clinical trajectory outlined in this study may provide valuable prognostic information for patients.

LEVEL OF EVIDENCE

3.

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.

Quality of Life and Cost Implications of Pseudarthrosis After Anterior Cervical Discectomy and Fusion and its Subsequent Revision Surgery

BACKGROUND

More than 120,000 anterior cervical discectomy and fusions (ACDFs) are performed annually. Pseudarthrosis is a potential delayed adverse event that affects up to 33% of patients. The degree to which this adverse event affects both patient quality-of-life (QOL) outcomes and health care costs is poorly understood.

METHODS

Patients who underwent revision surgery for pseudarthrosis between 2007 and 2012 were identified and matched to controls not experiencing pseudarthrosis in a 1:2 fashion (case/control). Cases and controls were compared regarding total health care costs incurred in the year after the index ACDF and QOL outcomes on the following metrics: EuroQol Five-Dimensions Questionnaire, Patient Health Questionnaire-9, and Pain Disability Questionnaire.

RESULTS

Of 738 patients who underwent ACDF, 11 underwent surgery for pseudarthrosis. No differences were noted between cases and controls regarding any of the matched variables. Patients in the pseudarthrosis cohort had poorer postoperative scores on the EuroQol Five-Dimensions Questionnaire mobility, usual activities, pain/discomfort, and quality-adjusted life-year dimensions. In addition, 64% of patients with pseudarthrosis had worsened quality-adjusted life-year scores compared with only 9% of controls (P < 0.01). Patients with pseudarthrosis also had poorer mental health (P < 0.01) and pain disability outcomes (P < 0.01) than did controls. Pseudarthrosis was associated with significant increases in direct costs, direct postoperative costs, and total costs (all P < 0.01).

CONCLUSIONS

This is the first study to characterize the effect of surgical revision for pseudarthrosis on both QOL outcomes and care costs after ACDF. Patients requiring revision experienced significantly poorer QOL outcomes and higher care costs relative to controls.

Poor Baseline Mental Health Does Not Influence Improvement in Patient-reported Outcomes, Satisfaction, and Return to Work Two Years After Single-level Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective study using prospectively collected registry data.

OBJECTIVE

The authors examine the influence of preoperative mental health on outcomes after anterior cervical discectomy and fusion (ACDF) and determine the impact of ACDF on postoperative mental health.

SUMMARY OF BACKGROUND DATA

While studies have reported a negative correlation between preoperative mental health and outcomes following lumbar spine surgery, the influence on outcomes following cervical spine surgery remains relatively understudied.

METHODS

Prospectively collected registry data of 104 patients who underwent single-level ACDF for cervical spondylotic myelopathy were reviewed. Patients were dichotomized into top and bottom halves based on preoperative SF-36 MCS (Mental Component Summary) using a cutoff of 48. Outcomes assessed were visual analogue scale for neck pain, arm pain, AAOS Neck Pain and Disability, Neurogenic Symptoms, Neck Disability Index, Short-Form 36, Japanese Orthopaedic Association myelopathy score, return to work, return to function, satisfaction and expectation fulfilment up to 2 years postoperatively.

RESULTS

The preoperative MCS was 37.5 ± 8.1 and 57.4 ± 6.3 in the Low and High MCS groups respectively (P < 0.001). The Low MCS group had poorer preoperative scores (P < 0.05). There was no significant difference in length of stay or comorbidities (P > 0.05). The High MCS group had less neck pain (P = 0.002) and showed a trend towards lower Neck Disability Index (P = 0.062) at 2 years. The Low MCS group demonstrated greater improvement in Japanese Orthopaedic Association (P = 0.007) and similar improvement in other scores (P > 0.05). There was no significant difference in proportion that achieved minimal clinically important difference for each score (P > 0.05). Both groups had similar rates of return to work, return to function, expectation fulfilment, and satisfaction (P > 0.05). Lower preoperative MCS was predictive of greater improvement in MCS (r = -0.477, P < 0.001).

CONCLUSION

Despite relatively greater pain and disability at 2 years, patients with poor baseline mental health experienced similar improvement in clinical outcomes, return to work, and satisfaction rates.

LEVEL OF EVIDENCE

3.