Risk Factors for Medical and Surgical Complications after 1-2-Level Anterior Cervical Discectomy and Fusion Procedures.

BACKGROUND: Postoperative complications after anterior cervical discectomy and fusion (ACDF) have a significant impact on clinical outcomes and health care resource use. Identifying predictive factors for complications after ACDF may allow for the modification of care protocols to mitigate complication risk. The purpose of this study is to determine risk factors for the incidence of medical and surgical complications up to 2 years postoperatively after ACDF procedures. METHODS: A prospectively maintained surgical registry of patients who underwent primary, 1-2-level ACDF was retrospectively reviewed. The incidence of medical and surgical complications up to 2 years postoperatively was determined. Patients were classified according to demographic, comorbidity, and procedural characteristics. Bivariate Poisson regression with robust error variance was used to determine if an association existed between the incidence of medical or surgical complications and patient characteristics. A final multivariate model including all patient and procedural characteristics as controls was created using backwards, stepwise regression until only those variables with P < .05 remained. RESULTS: A total of 310 patients were included. Upon bivariate analysis, age >50 years was identified as a risk factor for medical complications after ACDF procedures. Additionally, bivariate analysis identified ageless Charlson comorbidity index ≥2, operative duration >60 minutes, and 2-level procedures as risk factors for surgical complications after ACDF. Upon multivariate analysis, age >50 years was identified as an independent risk factor for medical complications (relative risk [RR] = 3.6, P = .005), while operative time >60 minutes was identified as an independent risk factor for surgical complications after ACDF (RR = 4.5, P = .017). CONCLUSIONS: The results of this study demonstrate that older age and longer operative time were independent risk factors for medical and surgical complications, respectively, following ACDF. Patients with these risk factors should be counseled regarding their increased risk of postoperative complications and should undergo more vigilant monitoring to aid in complication avoidance. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: Surgeons should consider the elevated risk of postoperative complications in >50 years old patients and >60 min procedures.

Risk Factors for Medical and Surgical Complications After Single-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion.

BACKGROUND: The prevention of perioperative and postoperative complications is necessary to avoid poor postoperative outcomes and increased costs. Previous investigations have identified risk factors for complications after various spine procedures, but no such study exists in a population solely undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). The purpose of this study is to determine risk factors for the development of complications up to 2 years after MIS TLIF procedures. METHODS: Patients who underwent primary, single-level MIS TLIF from 2007 to 2016 were retrospectively reviewed. The incidence of medical and surgical complications up to 2 years postoperatively was determined. Patients were categorized according to demographic, comorbidity, and procedural characteristics. Bivariate Poisson regression with robust error variance was used to determine if an association existed between patient characteristics and complication incidence. A final multivariate model including all patient characteristics as controls was created using backwards, stepwise regression until only those variables with P < .05 remained. RESULTS: 390 patients were analyzed. Upon bivariate analysis, age >50 years (P = .025), diabetes mellitus (P = .001), and operative duration >105 minutes (P = .016) were associated with increased medical complication rates. Regarding surgical complications, age ≤50 years (P < .001), obesity (P = .012), and diabetes mellitus (P = .042) were identified as risk factors on bivariate analysis. Upon final multivariate analysis, operative time >105 minutes (P = .009) and diabetes mellitus (P = .001) were independent risk factors for medical complications. Independent risk factors for surgical complications on multivariate analysis included age ≤50 years (P < .001), diabetes mellitus (P = .002), and obesity (P = .030). CONCLUSIONS: Diabetic patients and those who underwent longer operations were at increased risk of medical complications, while younger patients, obese patients and those also with diabetes mellitus were at increased risk of surgical complications up to 2 years after MIS TLIF. Practitioners can use this information to identify patients who require preventative care before their procedure or increased postoperative vigilance and monitoring after single-level MIS TLIF. LEVEL OF EVIDENCE: 3.

American Society of Anesthesiologists Score is Not Predictive of Complication Incidence After Minimally Invasive Posterior Lumbar Spine Procedures.

BACKGROUND: Complications occurring after spinal procedures are associated with recurrent symptomatology, new-onset symptomatology, and increased health care costs. The American Society of Anesthesiologists (ASA) score is a commonly cited risk factor for complication incidence. Few investigations have been performed analyzing the relationship between ASA score and complication rate following spinal minimally invasive surgery (MIS) decompressions or fusions. Therefore, the purpose of this study is to determine whether an association exists between preoperative ASA score and the incidence of postoperative complications among patients undergoing MIS posterior lumbar decompression or fusion. METHODS: A surgical registry of patients undergoing single-level MIS posterior lumbar decompressions or fusions between 2007 and 2016 was retrospectively reviewed. Patients were stratified by preoperative ASA score (≤2, >2). The ASA score was tested for an association with preoperative demographic, comorbidity, and perioperative characteristics using the Student t test or χ2 analysis. Multivariate Poisson regression with robust error variance was used to test for an association between ASA score and the incidence of complications up to 6 months postoperatively. RESULTS: A total of 772 patients were analyzed. Of those, 86.7% had an ASA score ≤2, whereas 13.3% had an ASA score >2. An ASA score >2 was associated with older age (P < .001), higher comorbidity burden (P < .001), and higher rates of obesity (P < .001). An ASA score >2 was also associated with significantly longer operative time (P = .001) and longer length of hospital stay (P < .001). Upon multivariate analysis, ASA score category was not associated with the incidence of any complication (P = .248), medical complications (P = .227), or surgical complications (P = .816). CONCLUSIONS: The ASA score was not a predictive factor for complication incidence up to 6 months postoperatively. Thus, a higher ASA score should not preclude patients from being surgical candidates for MIS posterior lumbar decompressions or fusions. Further investigation is required to identify other predictive factors for complication incidence after minimally invasive spine surgery. LEVEL OF EVIDENCE: 3.

Patient Perceptions of Physician Ownership in Spine Care.

STUDY DESIGN: This was a prospective study. OBJECTIVE: This study aims to determine the perspectives of patients seeking spine care in regard to physician ownership of surgical facilities and to understand the importance of disclosing financial conflicts. SUMMARY OF BACKGROUND DATA: There has been limited investigation regarding patient perceptions of the proprietary structure of surgical facilities. METHODS: Patients seeking treatment for spine pathology completed an 8-item survey. The questions assessed if patients acknowledged the owners of surgical facilities, if the patient thought knowledge of ownership is important, who they perceived as most qualified to own surgical facilities, preference of communication of ownership, and impact of facility ownership on care. RESULTS: A total of 200 patients completed the survey. When patients were asked whom they thought owned the hospital, most reported private hospital corporations followed by universities/medical schools and insurance companies. With regard to whom patients thought owned an ambulatory surgical center, most reported physicians, followed by private hospital corporations and individual investors. When asked how important it is to know the financial stakeholders of a surgical facility, 73.5% of patients stated "very important" or "somewhat important." Most patients reported they were not aware of who owned the facility. Regarding how facility owners should be communicated, 31.0% answered "written document," whereas 25.0% preferred verbal communication with the staff/surgeon. When asked how much impact the owner of a surgical facility has on their care, 38.0% of patients responded, "strong impact," followed by "moderate impact," (43.0%), and "little or no impact" (19.0%). Patients thought that physicians were the most qualified to own an ambulatory surgical center, followed by universities/medical schools and private hospital corporations. CONCLUSIONS: The pretreatment perception of patients referred to a spine clinic favored the opinion that physicians were the most qualified to own and manage surgical facilities. Therefore, physicians should be encouraged to share disclosures with patients as their ownership of surgical facilities is viewed favorably.

Outcomes of Expandable Interbody Devices in Lumbar Fusion: A Systematic Review and Meta-analysis.

STUDY DESIGN: This was a systematic review. OBJECTIVE: The objective of this study was to review radiographic, clinical, and surgical outcomes of expandable interbody device implantation following lumbar fusion. SUMMARY OF BACKGROUND DATA: Few studies have evaluated postsurgical outcomes of expandable implants following lumbar interbody fusion. METHODS: A systematic review was performed to identify studies investigating expandable intervertebral body devices in lumbar fusion. Radiographic parameters, fusion assessments, patient-reported outcomes (PROs), complications, and revision data were recorded. A comparison of expandable and static devices was performed using a meta-analysis. RESULTS: Eleven articles were included. Postoperative improvements for each radiographic parameters for expandable versus static device implantation ranged from: lumbar lordosis, +2.0 to +5.0 degrees (expandable) versus +1.0 to +4.4 degrees (static); segmental lordosis, +1.0 to +5.2 degrees (expandable) versus+1.1 to +2.3 degrees (static); disk height, +0.82 to +4.8 mm (expandable) versus +0.26 to +6.9 mm (static); foraminal height, +0.13 to +2.8 mm (expandable) versus and +0.05 to +3.0 mm (static). Fusion rates ranged from 72.1% at 6 months to 100% at terminal follow-up. Preoperative to final follow-up improvement for the various PROs assessed were: Oswestry Disability Index, -15.4 to -56.3 (expandable) versus -13.6 to -26.3 (static); Visual Analog Scale (VAS) Back, -3.2 to -6.0 (expandable) versus -3.1 to -4.1 (static); and VAS Leg, -2.9 to -7.1 (expandable) -3.0 versus -4.8 (static). Static cages had a reported complication rate ranging from 6.0% to 16.1% and a subsidence rate of 6.0%. Expandable cages had a reported complication rate that ranged from 0.0.% to 10.0% and a subsidence rate of 5.5%-10.0%. A meta-analysis demonstrated a statistically significant difference in the PRO Oswestry Disability Index, but not VAS Back, VAS Leg, or radiographic outcomes (disk height or foraminal height). CONCLUSION: There is no clear evidence for the use of expandable interbody devices over static devices.

Static Versus Expandable Devices Provide Similar Clinical Outcomes Following Minimally Invasive Transforaminal Lumbar Interbody Fusion.

BACKGROUND: Few studies have analyzed differences in radiographic parameters and patient-reported outcomes (PROs) between expandable and static interbody devices in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). QUESTIONS/PURPOSES: To evaluate differences in radiographic parameters and PROs following MIS TLIF between static and expandable interbody devices. METHODS: Patients undergoing primary, single-level MIS TLIF between 2014 and 2017 were retrospectively identified. Radiographic measurements including lumbar lordosis (LL), segmental lordosis (SL), disc height (DH), and foraminal height (FH) were performed on lateral radiographs before and after MIS TLIF with a static or expandable articulating interbody device. Radiographic outcomes and PROs were compared using paired and unpaired Student's t test. RESULTS: Thirty patients received expandable interbody devices and 30 patients received static interbody devices. The expandable device cohort exhibited significantly greater improvement in DH and FH at final follow-up compared with those receiving a static device. Both device cohorts experienced significant improvements in PROs at 6 months post-operatively. CONCLUSION: MIS TLIF with an expandable interbody device led to a greater increase of DH and FH than with a static interbody device. Patients undergoing MIS TLIF can expect similar improvements in PROs whether receiving a static or an expandable interbody device. Further studies are required to better understand improvements in clinical outcomes afforded by expandable interbody devices.

Postoperative Outcomes Based on American Society of Anesthesiologists Score After Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To examine the association between the American Society of Anesthesiologists (ASA) score and patient-reported outcomes (PROs) after minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: Few studies have investigated the correlation between ASA score and PROs after MIS TLIF. METHODS: Patients undergoing primary, single-level MIS TLIF were retrospectively reviewed and placed into 3 cohorts: ASA score ≤2 and outpatient status, ASA score ≤2 and inpatient status, and ASA score >2. Oswestry Disability Index (ODI), visual analog scale (VAS) back and leg pain, and Short Form-12 Physical Component Score (SF-12 PCS) were administered preoperatively and at 6-week, 12-week, and 6-month time points. ASA scores were tested for association with improvements in PROs using linear regression. RESULTS: A total of 187 patients had an ASA score ≤2 and 41 patients had an ASA score >2. Higher ASA scores were associated with older age, obesity, higher comorbidity burden, and an increased length of stay. ASA subgroups demonstrated a significant difference in preoperative ODI and VAS back pain scores and improvement in VAS back pain scores at the 12-week and 6-month time points; however, there was no discernible pattern of improvement amongst cohorts. No statistically significant differences were observed with improvements in PROs. CONCLUSIONS: The study suggests ASA scores are not associated with postoperative recovery in pain and disability after MIS TLIF. Our results indicate that regardless of the preoperative ASA score, patients are likely to achieve similar improvements in PROs through 6 months follow-up. Although using ASA as a risk stratification tool to predict perioperative complications, its utility in predicting improvement in PROs is still uncertain at this time.

All Disclosure is Good Disclosure: Patient Awareness of the Sunshine Act and Perceptions of Surgeon-Industry Relationships.

STUDY DESIGN: This was a prospective study. OBJECTIVE: To determine patient awareness of surgeon-industry relationships, how these relationships affect patient perceptions of surgeons, and which relationships cause the greatest concern to patients. SUMMARY OF BACKGROUND DATA: The prevalence of orthopedic surgeon-industry relationships led to the establishment of a national database of physician-industry interaction [Open Payments Database (OPD)] as part of the Physician Payments Sunshine Act (PPSA). MATERIALS AND METHODS: A 10-item questionnaire was administered to patients before their first evaluation. Two questions asked about awareness of the surgeon's industry relationships and of the OPD. One question evaluated the importance of surgeon-industry relationships of patients when choosing a provider. Six questions assessed patient perception of specific types of surgeon-industry relationships. Lastly, each patient ranked specific types of surgeon-industry relationships (1-most concerning to 6-least/not concerning). The distribution of patient-perceptions was compared using a Friedman 2-way analysis of variance by Ranks test. Distributions across awareness were compared using a Kruskal-Wallis test. RESULTS: A total of 205 patients completed the survey. A majority of patients were unaware of their surgeons' relationships with industry and the existence of the OPD. However, most patients considered surgeon-industry relationships an important, very important or most important part of choosing their physician. There were significant differences in how industry relationships affected patient perceptions. Research funding had the most positive impact on perception. Financial ownership was reported to be the most concerning relationship followed by royalty payments and consulting. CONCLUSIONS: Our results suggest that despite a lack of awareness, most patients consider surgeon-industry relationships an important factor in choosing their doctor. Patients generally report a more positive view of surgeons that have active relationships with industry. These results emphasize the value of disclosure for surgeons; it provides transparency and improves their standing amongst a majority of their patients.

Patient Perceptions of Iliac Crest Bone Grafting in Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: The objective of this study was to determine patients' perception of iliac crest bone graft (ICBG) harvesting and donor site pain following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: The incidence of donor site pain has been debated in the literature because of the varying techniques associated with its harvest. METHODS: Patients undergoing primary, single-level MIS TLIF with ICBG were retrospectively identified. ICBG harvesting was performed using a percutaneous technique with a tubular retractor. A survey was administered to assess if patients could accurately describe which side of their iliac crest they believed was harvested, and if they were experiencing any pain perceived to be originating from the donor site. Patient characteristics were compared using χ analysis and independent t test. RESULTS: In total, 82 patients were included. The majority of patients had the ICBG harvested from the left iliac crest (97.5%). Approximately half of the patients correctly identified the side of harvest (50.6%). 48.1% of patients reported they were not confident or had guessed on their response. Patients that reported pain from the ICBG were more likely to feel confident or somewhat confident in their harvest site identification (57.9% vs. 46.3%) but less likely to be correct (36.8% vs. 63.4%) than patients without pain. 22 patients (27.8%) correctly identified the side of harvest without guessing. Of these, 11 (13.9%) reported pain. CONCLUSIONS: Approximately half of patients undergoing MIS TLIF with ICBG are able to correctly identify which side of their iliac crest was harvested. However, the majority of patients reporting pain were unable to correctly identify the side of harvest. This suggests that most patients are likely attributing other sources of pain to their ICBG. Therefore, rates of donor site pain may be over-reported in the current literature with contemporary harvesting techniques.

Comparison of Multilevel Anterior Cervical Discectomy and Fusion Performed in an Inpatient Versus Outpatient Setting.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate differences in patient factors, procedural factors, early outcomes and safety in mutlilevel anterior cervical discectomy and fusion (ACDF) in the inpatient versus outpatient setting. METHODS: Patient demographics, operative factors, and outcomes of multilevel ACDF performed in an inpatient and outpatient setting were compared using Fisher's exact test for categorical and Student's t test for continuous variables. RESULTS: Fifty-seven patients had surgery on an outpatient and 46 on an inpatient basis. Inpatients were older (56.7 vs 52.2 years, P = .012) and had a higher ASA (American Society of Anesthesiologists) class (P = .002). Sixty percent of 2-level cases were outpatient surgeries, compared with 35% of 3-level cases (P = .042). Outpatients had shorter operative times (71.26 vs 83.59 minutes, P < .0001) and shorter lengths of stay (8.51 vs 35.76 hours, P < .0001), lower blood loss (33.04 vs 45.87 mL, P = .003), and fewer in-hospital complications (5.3% vs 37.0%, P < .0001). Outpatients had better early outcomes in terms of 6-week Neck Disability Index (NDI) (27.97 vs 37.59, P = .014), visual analogue scale (VAS) neck (2.92 vs 4.02, P = .044), and Short Form-12 Physical Health Score (SF-12 PHS) (35.66 vs 30.79, P = .008). However, these differences did not persist at 6 months. CONCLUSIONS: The results of our study suggest that multilevel ACDF can be performed safely in the outpatient setting without an increased risk of complications compared with the inpatient setting in an appropriately selected patient. Specifically, patients' age, ASA class, and number of levels being fused should be taken into consideration. At our institution, ASA class 3, body mass index >40 kg/m2, age >80 years, intubation time >2.5 hours, or not having a responsible adult with the patient warrant inpatient admission. Importantly, the setting of the surgery does not affect patient-reported outcomes.

Opioid Consumption Patterns After Lumbar Microdiscectomy or Decompression.

STUDY DESIGN: Prospective observational study OBJECTIVE.: The aim of this study was to record daily opioid use and pain levels after 1-level lumbar decompression or microdiscectomy. SUMMARY OF BACKGROUND DATA: The standardization of opioid-prescribing practices through guidelines can decrease the risk of misuse and lower the number of pills available for diversion in this high-risk patient population. However, there is a paucity of quantitative data on the "minimum necessary amount" of opioid appropriate for post-discharge prescriptions. METHODS: At two institutions between September 2017 and 2018, we prospectively enrolled 85 consecutive adult patients who underwent one-level lumbar decompression or microdiscectomy. Patients with a history of opioid dependence were excluded. Daily opioid consumption and pain scores were collected using an automated text-messaging-based platform for 6 weeks or until consumption ceased. Refills during the study period were monitored. Patients were asked for the number of pills left over and the method of disposal. Opioid use was converted to oral morphine equivalents (OMEs). Results are also reported in terms of "pills" (oxycodone 5 mg equivalents) to facilitate clinical applications. Risk factors were compared between patients in the top and bottom half of opioid consumption. RESULTS: Total opioid consumption ranged from 0 to 118 pills, with a median consumption of 32 pills (236.3 OME). Seventy-five percent of patients consumed ≤57 pills (431.3 OME). Mean Numeric Rating Scale pain scores declined steadily over the first 2 weeks. By postoperative day 7 half of the study population had ceased taking opioids altogether. Only 22.4% of patients finished their initial prescription, and only 9.4% of patients obtained a refill. CONCLUSION: These data may be used to formulate evidence-based opioid prescription guidelines, establish benchmarks, and identify patients at the higher end of the opioid use spectrum. LEVEL OF EVIDENCE: 2.

Minimal Clinically Important Difference and Substantial Clinical Benefit Using PROMIS CAT in Cervical Spine Surgery.

STUDY DESIGN: This was a prospective cohort study. OBJECTIVE: The objective of this study was to establish minimal clinically important difference (MCID) and substantial clinical benefit (SCB) thresholds for Patient-Reported Outcomes Measurement Information System (PROMIS) in cervical spine pathology. SUMMARY OF BACKGROUND DATA: PROMIS enables improved psychometric properties with reduced questionnaire burden through computer adaptive testing. Despite studies showing good correlation with "legacy" outcome measures, literature on the clinical significance of changes in PROMIS scores is scarce. MATERIALS AND METHODS: Adult patients undergoing cervical spine surgery at a single institution between 2016 and 2018 were prospectively enrolled. Patients completed questionnaires [Short Form-36 (SF-36), Neck Disability Index (NDI), Visual Analogue Scale Arm/Neck, and PROMIS Pain Interference (PI) and Physical Function (PF)] preoperatively and at 6 months postoperatively. MCID was calculated using distribution-based and SCB using anchor-based methods. The SF-36 Health Transition Item was utilized as an anchor with the cutoff values chosen using receiver operating characteristic curve analysis. RESULTS: There were 139 patients meeting inclusion criteria, with a mean age of 56.4 years and diagnoses of myelopathy (n=36), radiculopathy (n=48) and myeloradiculopathy (n=49). There were significant improvements in PROMIS PF, PROMIS PI, NDI, and SF-36 preoperatively to postoperatively (P<0.001). The test-retest reliability of all tests was excellent (intraclass correlation coefficients=0.87-0.94). PROMIS, SF-36, and NDI were all correlated with the anchor question (|r|=0.34-0.48, P<0.001). MCIDs were 8.5 (NDI), 11.1 (SF-36 Physical Component Score), 9.7 (SF-36 Mental Component Score), 4.9 (PROMIS PI), and 4.5 (PROMIS PF). SCB was 13.0 (NDI), 24.0 (SF-36 Physical Component Score), 11.8 (SF-36 Mental Component Score), 6.9 (PROMIS PI), and 6.8 (PROMIS PF). MCIDs were greater than standard error of measurement for all measures. CONCLUSIONS: We report MCID of 4.9 (PI) and 4.5 (PF) and SCB of 6.9 (PI) and 6.8 (PF). These data support the use of PROMIS computer adaptive tests in cervical spine patients and provide important reference as PROMIS reporting becomes more widespread in the literature.

The Influence of Conflicts of Interest on Outcomes in the Lumbar Disc Arthroplasty Literature: A Systematic Review.

STUDY DESIGN: A systematic review. OBJECTIVE: The aim of this study was to determine the association between study outcomes and the presence of a conflict of interest (COI) in the lumbar disc arthroplasty (LDA) literature. SUMMARY OF BACKGROUND DATA: Previous studies have evaluated the efficacy of LDA as a surgical alternative to arthrodesis. As investigators may have financial relationships with LDA device companies, it is important to consider the role of COI on study outcomes. METHODS: A systematic review was performed to identify articles reporting clinical outcomes of LDA. Any financial COIs disclosed were recorded and confirmed through Open Payments and ProPublica databases. Study outcomes were graded as favorable, unfavorable, or equivocal. Pearson Chi-squared analysis was used to determine an association between COI and study outcomes. Favorable outcomes were tested for an association with study characteristics using Poisson regression with robust error variance. RESULTS: Fifty-seven articles were included, 30 had a financial COI, while 27 did not. Ninety percent of the conflicted studies disclosed their COI in the article. Studies with United States authors were more likely to be conflicted (P = 0.019). A majority of studies reported favorable outcomes for LDA (n = 39). Conflicted studies were more likely to report favorable outcomes than nonconflicted studies (P = 0.020). Articles with COIs related to consultant fees (P = 0.003), research funding (P = 0.002), and stock ownership (P < 0.001) were more likely to report favorable outcomes. CONCLUSION: This study highlights the importance for authors to accurately report conflicting relationships with industry. As such, orthopedic surgeons should critically evaluate study outcomes with regard to potential conflicts before recommending LDA as a surgical option to their patients. LEVEL OF EVIDENCE: 3.

Risk Factors Associated With Failure to Reach Minimal Clinically Important Difference in Patient-Reported Outcomes Following Anterior Cervical Discectomy and Fusion.

BACKGROUND: The minimum clinically importance difference (MCID) represents a threshold for improvements in patient-reported outcomes (PROs) that patients deem important. No previous study has comprehensively examined risk factors for failure to achieve MCID after anterior cervical discectomy and fusion (ACDF) procedures for radiculopathic symptomatology. The purpose of this study is to determine risk factors for failure to reach MCID for Neck Disability Index (NDI), Visual Analog Scale (VAS) neck pain, and VAS arm pain in patients undergoing 1- or 2-level ACDF procedures. METHODS: A surgical registry of patients who underwent primary, 1- or 2-level ACDF from 2014 to 2016 was reviewed. Rates of MCID achievement for NDI, VAS neck pain, and VAS arm pain at final follow-up were calculated based on published MCID values. Patients were then categorized into demographic and procedural categories. Bivariate regression was used to test for association of demographic and procedural characteristics with failure to reach MCID for each PRO. The final multivariate model including all demographic and procedural categories as controls was created using backward stepwise regression. RESULTS: Eighty-three, 84, and 77 patients were included in the analysis for VAS neck, VAS arm, and NDI, respectively. Rates of MCID achievement for VAS neck, VAS arm, and NDI were 55.4%, 36.9%, and 76.6%, respectively. On bivariate analysis, patients with Charlson Comorbidity Index (CCI) ≥ 2 were less likely to achieve MCID for NDI than patients with CCI < 2 (P = .025). On multivariate analysis, CCI ≥ 2 (P = .025) was further associated with failure to reach MCID for NDI. CONCLUSIONS: The results of this study suggest that the majority of patients do not reach MCID for arm pain. Additionally, higher comorbidity burden as evidenced by higher CCI scores is a negative predictive factor for the achievement of MCID in neck disability following ACDF. LEVEL OF EVIDENCE: 3.

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.

Impact of Iliac Crest Bone Grafting on Postoperative Outcomes and Complication Rates Following Minimally Invasive Transforaminal Lumbar Interbody Fusion.

OBJECTIVE: The relationship between bone graft technique and postoperative outcomes for minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) has not been well-defined. This study aims to determine the effect of iliac crest bone grafting (ICBG) on patient-reported outcomes (PROs) and complication rates following MIS TLIF. METHODS: Primary, single-level MIS TLIF patients were consecutively analyzed. Patients that prospectively received a percutaneous technique of ICBG were compared to patients that retrospectively received bone morphogenetic protein-2 (BMP-2). Complication rates were assessed perioperatively and up to 1 year postoperatively. Changes in Oswestry Disability Index (ODI), visual analogue scale (VAS) back, and VAS leg pain were compared. Rates of minimum clinically important difference (MCID) achievement at final follow-up for ODI, VAS back, and VAS leg scores were compared. RESULTS: One hundred forty-nine patients were included: 101 in the BMP-2 cohort and 48 in the ICBG cohort. The ICBG cohort demonstrated increases in intraoperative blood loss and shorter lengths of stay. ICBG patients also experienced longer operative times, though this did not reach statistical significance. No significant differences in complication or reoperation rates were identified. The ICBG cohort demonstrated greater improvements in VAS leg pain at 6-week and 12-week follow-up. No other significant differences in PROs or MCID achievement rates were identified. CONCLUSION: Patients undergoing MIS TLIF with ICBG experienced clinically insignificant increases in intraoperative blood loss and did not experience increases in postoperative pain or disability. Complication and reoperation rates were similar between groups. These results suggest that ICBG is a safe option for MIS TLIF.

Swallowing Function Following Anterior Cervical Discectomy and Fusion With and Without Anterior Plating: A SWAL-QOL (Swallowing-Quality of Life) and Radiographic Assessment.

OBJECTIVE: Anterior cervical plating in anterior cervical discectomy and fusion (ACDF) procedures are associated with improved outcomes compared to stand-alone cages. However, concerns exist regarding increased rates of postoperative dysphagia following an ACDF. This study aims to quantify the effect of anterior plating on swallowing-quality of life (SWAL-QOL) scores and radiographic swelling assessments following a primary, single-level ACDF. METHODS: Patients retrospectively reviewed. Patients grouped into those receiving a cage or anterior plate. SWAL-QOL scores were recorded preoperatively and 6 weeks and 12 weeks postoperatively. Lateral radiographs were used to create a swelling index with a ratio of the prevertebral swelling distance to the anterior-posterior diameter of each involved vertebral body. An air index was created using the same methodology. Statistical analysis was performed using chi-square analysis and independent t-tests for categorical and continuous variables. RESULTS: Sixty-eight primary, single-level ACDF patients were included. Forty-one (60.3%) received a stand-alone cage and 27 (39.7%) received a cage with anterior plating. No differences in demographics, comorbidities, operative time, estimated blood loss, or length of hospital stay were identified between Cage and Plate cohorts. Finally, no differences were observed in postoperative SWAL-QOL scores or swelling and air indices between groups. CONCLUSION: The results demonstrate that patients undergoing a primary, single-level ACDF with or without anterior plating experience similar operative times and lengths of stay. Patients that receive a cage with anterior plating did not experience significant increases in dysphagia as measured by the SWAL-QOL questionnaire compared to patients that received a stand-alone cage. Furthermore, radiographic assessments of swelling are comparable.

Narcotic Consumption Following Minimally Invasive Lumbar Decompression: A Comparison Between Hospital and Ambulatory-Based Surgery Centers.

BACKGROUND: Several studies have compared outcomes between hospital-based centers (HBCs) and ambulatory surgery centers (ASCs) following minimally invasive lumbar decompression (MIS LD). However, the association between narcotic consumption and pain in the immediate postoperative period has not been well characterized. As such, this study aims to examine pain, narcotic consumption, and length of stay (LOS) among patients discharged on postoperative day 0 following a 1-level MIS LD between HBCs or ASCs. METHODS: Patients who underwent a primary, 1-level MIS LD were retrospectively reviewed and stratified by operative location. Differences between groups in patient demographics were assessed using independent-sample t tests for continuous variables and χ2 analysis for categoric variables. The operative location and its effect on perioperative characteristics, inpatient pain scores, and narcotics consumption were analyzed using multivariate linear regression adjusted for significant patient characteristics. RESULTS: There were 235 patients identified, of whom 90 and 145 underwent surgery at an HBC or ASC, respectively. The HBC cohort exhibited an increased comorbidity burden and had a greater percentage of privately insured patients. The HBC cohort recorded shorter operative time and greater total estimated blood loss. Patients in the HBC cohort experienced prolonged LOS, and consumed greater total oral morphine equivalents compared with the ASC cohort. No differences were observed in the remaining outcomes. CONCLUSIONS: The results of the current study suggest that patients who underwent MIS LD at an ASC received fewer narcotics than patients treated at an HBC, which may contribute to shortened LOS. Additionally, there was no difference in patient-reported pain between cohorts despite the differences in narcotic use. As such, postoperative narcotics administration varied, indicating HBC patients perhaps required more narcotic pain medications to achieve the same pain scores that were sufficient enough to allow patient discharge, thus prolonging LOS. LEVEL OF EVIDENCE: III.

PHQ-9 Score Predicts Postoperative Outcomes Following Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: This study evaluates if an association exists between preoperative depression and postoperative outcomes following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: Few studies have quantified preoperative depression symptoms using Patient Health Questionnaire-9 (PHQ-9) to predict postoperative outcomes after lumbar fusion, especially MIS TLIF. METHODS: A surgical database of patients undergoing primary, single-level MIS TLIF was retrospectively reviewed. Patients were stratified by predefined preoperative PHQ-9 scores: no depression (<5), mild depression (5-9), and moderate to severe depression (≥10). Inpatient pain scores and narcotics use were recorded. Oswestry Disability Index, Veterans RAND-12 Mental Component Score and Physical Component Score, and Visual Analog Scale (VAS) back and leg pain scores were collected preoperatively and at 6-week, 12-week, and 6-month follow-up. One-way analysis of variance and χ analysis determined if an association existed between PHQ-9 subgroups and baseline characteristics or perioperative outcomes. Multivariate linear regression assessed for an association between PHQ-9 and postoperative patient-reported outcomes. RESULTS: In total, 94 patients were included. Patients with higher PHQ-9 scores were younger, obese, and carried workers' compensation insurance. Higher PHQ-9 scores were associated with worse preoperative Oswestry Disability Index, Veterans RAND-12 Mental Component Score and Physical Component Score, and VAS back and leg pain scores. Patients with higher PHQ-9 reported greater inpatient VAS pain scores on postoperative day 0 and 1 and demonstrated greater hourly narcotics consumption on postoperative day 0. Furthermore, higher PHQ-9 scores exhibited less improvement in all patient-reported outcomes. CONCLUSIONS: Patients with severe depression symptoms reported greater pain, increased narcotics consumption, and less clinical improvement after MIS TLIF. Therefore, patients with greater PHQ-9 scores should be monitored more closely and may benefit from additional counseling with regard to postoperative outcomes to better manage pain control and expectations of recovery.

Comparative analysis of anterior cervical discectomy and fusion in the inpatient versus outpatient surgical setting.

OBJECTIVEIn a large, consecutive series of patients treated with anterior cervical discectomy and fusion (ACDF) performed by a single surgeon, the authors compared the clinical and surgical outcomes of patients who underwent ACDF in an inpatient versus outpatient setting.METHODSPatients undergoing primary ACDF were retrospectively reviewed and stratified by surgical setting: hospital or ambulatory surgical center (ASC). Data regarding perioperative characteristics, including hospital length of stay and complications, were collected. Neck Disability Index (NDI) and visual analog scale (VAS) scores were used to analyze neck and arm pain in the preoperative period and at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Postoperative outcomes were compared using chi-square analysis and linear regression.RESULTSThe study included 272 consecutive patients undergoing a primary ACDF, of whom 172 patients underwent surgery at a hospital and 100 patients underwent surgery at an ASC. Patients undergoing ACDF in the hospital setting were older, more likely to be diabetic, and had a higher comorbidity burden. Patients receiving treatment in the ASC were more likely to carry Workers' Compensation insurance. Patients in the hospital cohort were more likely to have multilevel procedures, had greater blood loss, and experienced a longer length of stay. In the hospital cohort, 48.3% of patients were discharged within 24 hours, while 43.0% were discharged between 24 and 48 hours after admission. Both cohorts had similar VAS pain scores on postoperative day (POD) 0; however, the hospital cohort consumed more narcotics on POD 0. One patient in the ASC cohort had a pretracheal hematoma that was evacuated immediately in the same surgical center. There were 8 cases of dysphagia in the hospital cohort and 3 cases in the ASC cohort, all of which resolved before the 6-month follow-up. Both cohorts demonstrated similar NDI and VAS neck and arm pain scores preoperatively and at every postoperative time point.CONCLUSIONSAlthough patients undergoing ACDF in the hospital setting were older, had a greater comorbidity burden, and underwent surgery on more levels than patients undergoing ACDF at an outpatient center, this study demonstrated comparable surgical and clinical outcomes for both patient groups. Based on the results of this single surgeon's experience, 1- to 2-level ACDFs may be performed successfully in the outpatient setting in appropriately selected patient populations.