A Review of Vitamin D in Spinal Surgery: Deficiency Screening, Treatment, and Outcomes.

In this review, we discuss the demonstrated value of vitamin D in bone maintenance, fracture resistance, spinal health, and spine surgery outcomes. Despite this, the effect of vitamin D levels in spine surgery has not been well described. Through this review of literature, several conclusions were drawn. First, despite the fact that a high number of spine surgery patients are vitamin D deficient, screening is not commonly performed. Second, adequate vitamin D levels will not be achieved in a majority of these patients without supplementation. Last, inadequate vitamin D levels may increase the risk of pseudarthrosis. Given these findings, we suggest that many patients undergoing spinal surgery could be treated with vitamin D supplementation prior to surgery without the need for confirmatory testing for vitamin D deficiency. This is a more cost-effective method than screening all patients. However, future randomized trials and cost-effectiveness analyses are needed to determine the ultimate effects of vitamin D supplementation on clinical morbidity and surgical outcomes.

Minimally Invasive Transforaminal Lumbar Interbody Fusion: Comparison of Grade I Versus Grade II Isthmic Spondylolisthesis.

BACKGROUND: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is often used to treat low-grade isthmic spondylolisthesis (IS). No studies have compared surgical outcomes for grade I and II IS following MIS-TLIF. Therefore, the objective of the current study was to compare outcomes between patients with grade I and II IS following MIS-TLIF. METHODS: A retrospective cohort analysis was performed on a prospectively maintained database of patients who underwent a primary 1-level MIS-TLIF for treatment of IS between 2007 and 2015. Grade I patients underwent a unilateral tubular approach with a single interbody cage and bilateral pedicle screw instrumentation. Grade II patients underwent a bilateral tubular approach with bilateral interbody cage and pedicle screw placement. Baseline patient demographics and characteristics were compared using Student t test and χ2 analysis. Differences in peri- and postoperative outcomes were assessed using Poisson regression with robust error variance or linear regression adjusted for perioperative variables. RESULTS: A total of 58 patients with IS underwent MIS-TLIF; 21 (36.2%) were grade I and 37 (63.8%) were grade II. The grade I cohort was younger (42.2 versus 50.6 years, P = .029); no other differences in preoperative variables were observed. No significant differences in operative time, estimated blood loss, length of hospital stay, postoperative visual analogue scale scores, or complication and revision rates were demonstrated between cohorts. Arthrodesis rate was lower in the grade I cohort, though not statistically significant. CONCLUSIONS: Despite the grade I cohort being younger with less-severe diagnoses, the grade II cohort experienced similar outcomes. This finding may be due to the grade II cohort receiving bilateral cages, potentially providing a better fusion environment. CLINICAL RELEVANCE: These results suggest that MIS-TLIF provides sufficient stabilization and fusion for treatment of grade II IS despite increased vertebral body displacement. In addition, MIS-TLIF with bilateral approach and interbody cage placement should be examined for treatment of high-grade IS cases.

Minimally Invasive Transforaminal Lumbar Interbody Fusion: Comparison of Isthmic Versus Degenerative Spondylolisthesis.

BACKGROUND: Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is a common surgical procedure for treatment of degenerative spondylolisthesis (DS) but remains controversial for treatment of isthmic spondylolisthesis (IS). Few studies have compared IS and DS outcomes after MIS TLIF. Therefore, the objective of the current study was to compare outcomes of patients with IS and DS after MIS TLIF. METHODS: A retrospective cohort analysis was performed on a prospectively maintained database of patients who underwent a primary, 1-level MIS TLIF for grade I or II IS or DS. Grade I and II DS and grade I IS patients were treated with MIS TLIF via a unilateral tubular approach, whereas the grade II IS patients were treated via a bilateral tubular approach. Differences in patient demographics and preoperative characteristics were assessed using independent sample t tests and χ2 tests. The type of spondylolisthesis and its effect on postoperative outcomes was analyzed using Poisson regression with robust error variance (binary outcomes) or linear regression (continuous outcomes) adjusted for preoperative characteristics. Subgroup analysis comparing grade I IS versus DS and grade II IS versus DS was performed. RESULTS: A total of 223 patients were included (IS: 62 [27.8%]; DS: 161 [72.2%]). IS patients were younger (P < .001), had a lower comorbidity burden (P < .001), and a greater incidence of grade II spondylolisthesis (P < .001) at L5-S1 (P < .001) than the DS cohort. Patients with IS experienced longer operative times (P < .001) and lower, but not statistically significant, arthrodesis rates compared to the DS cohort. No differences were observed in the remaining preoperative patient characteristics, perioperative or postoperative outcomes. CONCLUSIONS: Despite being younger and having a lower comorbidity burden than the DS cohort, similar outcomes were observed after MIS TLIF for IS patients. LEVEL OF EVIDENCE: 3. CLINICAL RELEVANCE: These results suggest MIS TLIF is an appropriate treatment option for IS patients despite the increased instability inherent with IS.

Assessing Online Patient Education Readability for Spine Surgery Procedures.

BACKGROUND CONTEXT: Increased patient reliance on Internet-based health information has amplified the need for comprehensible online patient education articles. As suggested by the American Medical Association and National Institute of Health, spine fusion articles should be written for a 4th-6th-grade reading level to increase patient comprehension, which may improve postoperative outcomes. PURPOSE: The purpose of this study is to determine the readability of online health care education information relating to anterior cervical discectomy and fusion (ACDF) and lumbar fusion procedures. STUDY DESIGN: Online health-education resource qualitative analysis. METHODS: Three search engines were utilized to access patient education articles for common cervical and lumbar spine procedures. Relevant articles were analyzed for readability using Readability Studio Professional Edition software (Oleander Software Ltd). Articles were stratified by organization type as follows: General Medical Websites (GMW), Healthcare Network/Academic Institutions (HNAI), and Private Practices (PP). Thirteen common readability tests were performed with the mean readability of each compared between subgroups using analysis of variance. RESULTS: ACDF and lumbar fusion articles were determined to have a mean readability of 10.7±1.5 and 11.3±1.6, respectively. GMW, HNAI, and PP subgroups had a mean readability of 10.9±2.9, 10.7±2.8, and 10.7±2.5 for ACDF and 10.9±3.0, 10.8±2.9, and 11.6±2.7 for lumbar fusion articles. Of 310 total articles, only 6 (3 ACDF and 3 lumbar fusion) were written for comprehension below a 7th-grade reading level. CONCLUSIONS: Current online literature from medical websites containing information regarding ACDF and lumbar fusion procedures are written at a grade level higher than the suggested guidelines. Therefore, current patient education articles should be revised to accommodate the average reading level in the United States and may result in improved patient comprehension and postoperative outcomes.

Narcotic Consumption Following Anterior and Lateral Lumbar Interbody Fusion Procedures.

STUDY DESIGN/SETTING: This is a retrospective analysis of a prospectively maintained surgical registry. OBJECTIVE: To characterize postoperative narcotic consumption in patients undergoing either an anterior lumbar interbody fusion (ALIF) or a lateral lumbar interbody fusion (LLIF). BACKGROUND CONTEXT: There is substantial interest in evaluating the safety, efficacy, and outcomes following minimally invasive techniques for lumbar fusion procedures. However, few studies have characterized postoperative narcotic consumption in patients undergoing ALIF or LLIF procedures. METHODS: Consecutive patients who underwent either an ALIF or LLIF during 2007-2014 were identified. Inpatient narcotic consumption was recorded in oral morphine equivalents and dichotomized as greater or less than the 75th percentile total consumption (elevated or normal inpatient consumption). Demographic, comorbidity, and perioperative characteristics were tested for independent association with inpatient narcotic consumption and with continued narcotic usage during the months following surgery. RESULTS: A total of 169 patients met inclusion criteria. Of these, 118 (69.8%) underwent ALIF and 51 (30.2%) underwent LLIF procedures. The risk for elevated inpatient narcotic consumption was greater in patients whose body mass index was≥30 kg/m [relative risk (RR), 2.8; 95% confidence interval (CI), 1.6-4.8; P<0.001). The risk for continued narcotic usage at the first postoperative visit was elevated in patients with worker's compensation payment status (RR, 2.0; 95% CI, 1.5-2.7; P<0.001). The risk for continued narcotic usage at the second postoperative visit was elevated in patients with worker's compensation payment status (RR, 2.6; 95% CI, 1.7-4.1; P<0.001) and in patients with preoperative narcotic utilization (RR, 2.2; 95% CI, 1.4-3.5; P<0.001). CONCLUSIONS: The present study suggests that while patients with greater body mass index have increased narcotic consumption as inpatients, preoperative narcotic consumption and worker's compensation payment status are the best predictors of continued narcotics usage during the months following surgery. Worker's compensation patients and patients who utilize narcotics preoperatively should be the targets of efforts to reduce continued postoperative narcotic usage.

Preoperative mental health status may not be predictive of improvements in patient-reported outcomes following an anterior cervical discectomy and fusion.

OBJECTIVE Prior studies have correlated preoperative depression and poor mental health status with inferior patient-reported outcomes following lumbar spinal procedures. However, literature regarding the effect of mental health on outcomes following cervical spinal surgery is limited. As such, the purpose of this study is to test for the association of preoperative SF-12 Mental Component Summary (MCS) scores with improvements in Neck Disability Index (NDI), SF-12 Physical Component Summary (PCS), and neck and arm pain following anterior cervical discectomy and fusion (ACDF). METHODS A prospectively maintained surgical database of patients who underwent a primary 1- or 2-level ACDF during 2014-2015 was reviewed. Patients were excluded if they did not have complete patient-reported outcome data for the preoperative or 6-week, 12-week, or 6-month postoperative visits. At baseline, preoperative SF-12 MCS score was assessed for association with preoperative NDI, neck visual analog scale (VAS) score, arm VAS score, and SF-12 PCS score. The preoperative MCS score was then tested for association with changes in NDI, neck VAS, arm VAS, and SF-12 PCS scores from the preoperative visit to postoperative visits. These tests were conducted using multivariate regression controlling for baseline characteristics as well as for the preoperative score for the patient-reported outcome being assessed. RESULTS A total of 52 patients were included in the analysis. At baseline, a higher preoperative MCS score was negatively associated with a lower preoperative NDI (coefficient: -0.74, p < 0.001) and preoperative arm VAS score (-0.06, p = 0.026), but not preoperative neck VAS score (-0.03, p = 0.325) or SF-12 PCS score (0.04, p = 0.664). Additionally, there was no association between preoperative MCS score and improvement in NDI, neck VAS, arm VAS, or SF-12 PCS score at any of the postoperative time points (6 weeks, 12 weeks, and 6 months, p > 0.05 for each). The percentage of patients achieving a minimum clinically important difference at 6 months did not differ between the bottom and top MCS score halves (p > 0.05 for each). CONCLUSIONS The results of this study suggest that better preoperative mental health status is associated with lower perceived preoperative disability but is not associated with severity of preoperative neck or arm pain. In contrast to other studies, the present study was unable to demonstrate that preoperative mental health is predictive of improvement in patient-reported outcomes at any postoperative time point following an ACDF.

Patient knowledge regarding radiation exposure from spinal imaging.

BACKGROUND CONTEXT: Spine surgeons employ a high volume of imaging in the diagnosis and evaluation of spinal pathology. However, little is known regarding patients' knowledge of the radiation exposure associated with these imaging techniques. PURPOSE: To characterize spine patients' knowledge regarding radiation exposure from various imaging modalities. STUDY DESIGN/SETTING: A cross-sectional survey study. PATIENT SAMPLE: One hundred patients at their first clinic visit with a single spine surgeon at an urban institution. OUTCOME MEASURES: The primary outcome was patient estimate of radiation dose for various common spinal imaging modalities as compared with true dose. METHODS: An electronic survey was administered to all new patients before their first appointment with a single spinal surgeon. The survey asked patients to estimate how many chest x-rays (CXRs) worth of radiation were equivalent to various common spinal imaging modalities. Patient estimates were compared to true effective radiation doses determined from the literature. The survey also asked patients whether they would consider avoiding types of imaging modalities out of concern for excessive radiation exposure. RESULTS: Patients accurately approximated the radiation associated with two views of the cervical spine, with a median estimate of 3.5 CXRs, compared with an actual value of 4.7 CXRs. However, patients underestimated the dose for computed tomography (CT) scans of the cervical spine (2.0 CXRs vs. 145.3 CXRs), two views of the lumbar spine (3.0 CXRs vs. 123.3 CXRs), and CT scans of the lumbar spine (2.0 CXRs vs. 638.3 CXRs). The majority of patients believed that there is at least some radiation exposure associated with magnetic resonance imaging (MRI). The percent of patients who would consider forgoing imaging recommend by their surgeon out of concern for radiation exposure was 14% for x-rays, 13% for CT scans, and 9% for MRI. CONCLUSION: These results demonstrate a lack of patient understanding regarding radiation exposure associated with common spinal imaging techniques. These data suggest that patients might benefit from increased counseling and/or educational materials regarding radiation exposure before undergoing diagnostic imaging of the cervical or lumbar spine.

Improvements in Neck and Arm Pain Following an Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: A retrospective analysis. OBJECTIVE: The aim of this study was to quantify improvements in Visual Analogue Scale (VAS) neck and arm pain, Neck Disability Index (NDI), and Short Form-12 (SF-12) Mental (MCS) and Physical (PCS) Composite scores following an anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: ACDF is evaluated with patient-reported outcomes. However, the extent to which these outcomes improve following ACDF remains poorly defined. METHODS: A surgical registry of patients who underwent primary, one- or two-level ACDF during 2013 to 2015 was reviewed. Comparisons of VAS neck and arm, NDI, and SF-12 MCS and PCS scores were performed using paired t tests from preoperative to each postoperative time point. Analysis of variance (ANOVA) was used to estimate the reduction in neck and arm pain over the first postoperative year. Subgroup analyses were performed for patients with predominant neck (pNP) or arm (pAP) pain, as well as for one- versus two-level ACDF. RESULTS: Eighty-nine patients were identified. VAS neck and arm, NDI, and SF-12 PCS improved from preoperative scores at all postoperative time points (P < 0.05 for each). Across the first postoperative year, patients reported a 2.7-point (44.2%) reduction in neck and a 3.1-point (54.0%) reduction in arm pain (P < 0.05 for each). Sixty-one patients with pNP and 28 patients with pAP reported reductions in neck and arm pain over the first 6 months and 12 weeks postoperatively, respectively (P < 0.05 for each). Patients who underwent one-level ACDFs experienced a 47.2% reduction in neck pain and 55.1% reduction in arm pain over the first postoperative year (P < 0.05 for each), while those undergoing two-level ACDF experienced 39.7% and 49.2% for neck and arm, respectively (P < 0.05 for each). CONCLUSION: This study suggests that patients experience significant improvements in neck and arm pain following ACDF regardless of presenting symptom. In addition, patients undergoing one-level ACDF report greater reductions in neck and arm pain than patients undergoing two-level fusion. LEVEL OF EVIDENCE: 4.

Spinal Surgeon Variation in Single-Level Cervical Fusion Procedures: A Cost and Hospital Resource Utilization Analysis.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To compare perioperative costs and outcomes of patients undergoing single-level anterior cervical discectomy and fusions (ACDF) at both a service (orthopedic vs. neurosurgical) and individual surgeon level. SUMMARY OF BACKGROUND DATA: Hospital systems are experiencing significant pressure to increase value of care by reducing costs while maintaining or improving patient-centered outcomes. Few studies have examined the cost-effectiveness cervical arthrodesis at a service level. METHODS: A retrospective review of patients who underwent a primary 1-level ACDF by eight surgeons (four orthopedic and four neurosurgical) at a single academic institution between 2013 and 2015 was performed. Patients were identified by Diagnosis-Related Group and procedural codes. Patients with the ninth revision of the International Classification of Diseases coding for degenerative cervical pathology were included. Patients were excluded if they exhibited preoperative diagnoses or postoperative social work issues affecting their length of stay. Comparisons of preoperative demographics were performed using Student t tests and chi-squared analysis. Perioperative outcomes and costs for hospital services were compared using multivariate regression adjusted for preoperative characteristics. RESULTS: A total of 137 patients diagnosed with cervical degeneration underwent single-level ACDF; 44 and 93 were performed by orthopedic surgeons and neurosurgeons, respectively. There was no difference in patient demographics. ACDF procedures performed by orthopedic surgeons demonstrated shorter operative times (89.1 ±â€Š25.5 vs. 96.0 ±â€Š25.5 min; P = 0.002) and higher laboratory costs (Δ+$6.53 ±â€Š$5.52 USD; P = 0.041). There were significant differences in operative time (P = 0.014) and labor costs (P = 0.034) between individual surgeons. There was no difference in total costs between specialties or individual surgeons. CONCLUSION: Surgical subspecialty training does not significantly affect total costs of ACDF procedures. Costs can, however, vary between individual surgeons based on operative times. Variation between individual surgeons highlights potential areas for improvement of the cost effectiveness of spinal procedures. LEVEL OF EVIDENCE: 4.

Preoperative Mental Health is not Predictive of Patient-reported Outcomes Following a Minimally Invasive Lumbar Discectomy.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: To determine if preoperative mental health is associated with patient-reported outcomes (PROs) following a minimally invasive lumbar discectomy. SUMMARY OF BACKGROUND DATA: PROs are commonly used to quantify a patient's perceived health status. Recently, mental health has been theorized to directly affect patients' perception of their disability and pain after spine surgery. MATERIALS AND METHODS: A registry of patients who underwent a primary, single-level minimally invasive lumbar discectomy was reviewed. The association between preoperative Short-Form Health Survey mental composite score (MCS) and change in PROs [Oswestry Disability Index, back and leg visual analog scale (VAS) pain scores] from preoperative to postoperative (6-week, 12-week, 6-month) timepoints was assessed using multivariate regression controlling for patient demographics and the respective preoperative PRO. Patients in the top and bottom quartiles of preoperative MCS were compared regarding achievement of minimum clinically important difference for each PRO. RESULTS: A total of 110 patients were included in the analysis. Better preoperative mental health was associated with lower preoperative disability and decreased preoperative back VAS (P<0.05 for each). Higher preoperative MCS was also associated with greater improvements in back VAS at 6-weeks postoperatively (P<0.05). There was no association between preoperative MCS and change in any PROs at the 12-week or 6-month postoperative visits. Patients in the bottom quartile of preoperative MCS achieved minimum clinically important difference in all PROs at similar rates to patients in the top quartile of preoperative MCS. CONCLUSIONS: Patients with better preoperative mental health scores are more likely to report decreased disability and pain preoperatively. However, preoperative mental health was not predictive of changes in long-term disability or pain. As a result, patients with a wide range of preoperative mental health scores can achieve satisfactory long-term reductions in disability and pain levels after a lumbar discectomy. LEVEL OF EVIDENCE: Level IV.

Multimodal Analgesia Versus Intravenous Patient-Controlled Analgesia for Minimally Invasive Transforaminal Lumbar Interbody Fusion Procedures.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To compare postoperative narcotic consumption and pain scores between multimodal analgesia (MMA) and patient-controlled analgesia (PCA) following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: A multimodal analgesic approach to pain management may lead to decreased pain and narcotic consumption after orthopedic procedures. Additional evidence is, however, required to determine how MMA compares to intravenous PCA after MIS TLIF. METHODS: Patients undergoing 1-level MIS TLIF followed by either MMA or PCA at our institution were compared in terms of inpatient pain scores, narcotic consumption, hospital length of stay, rates of surgical complications, rates of inpatient nausea/vomiting, rates of postoperative urinary retention, and rates of narcotic consumption during the months after discharge. RESULTS: A total of 139 patients met inclusion criteria. Of these, 39 (28.1%) received MMA and 100 (71.9%) received PCA. Demographic and comorbidity characteristics did not differ between cohorts. Compared with patients receiving PCA, patients receiving MMA had a lower rate of inpatient narcotic consumption (2.8 ±â€Š1.9 vs. 5.3 ±â€Š4.4 oral morphine equivalents/hour, P < 0.001), a lower rate of inpatient nausea/vomiting (20.5% vs. 48.0%; P = 0.003), and a shorter hospital length of stay (53.0 ±â€Š25.3 vs. 62.6 ±â€Š24.4 h, P = 0.041). There were no differences in Numeric Rating Scale pain score between cohorts for day 0, postoperative day 1, or postoperative day 2 (P > 0.05 for each). There was no difference in the rate of postoperative urinary retention (P > 0.05). Similarly, there were no differences in narcotic consumption at 6 or 12 weeks postoperatively (P > 0.05 for each). CONCLUSION: These findings suggest that MMA results in reduced inpatient hospital narcotic consumption compared with PCA after MIS TLIF. The decrease in narcotic consumption may contribute to the observed decrease in the rate of inpatient nausea/vomiting and shorter hospital length of stay. Importantly, MMA and PCA resulted in similar analgesia for patients during the inpatient stay. LEVEL OF EVIDENCE: 4.

Effect of Surgery Start Time on Day of Discharge in Anterior Cervical Discectomy and Fusion Patients.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To compare time to discharge for anterior cervical discectomy and fusions (ACDF) when performed as either a first case versus later surgical start times. SUMMARY OF BACKGROUND DATA: ACDF is a commonly performed spinal procedure that typically has a short acute recovery period. With an increasing focus on reducing hospital costs and a shift toward outpatient surgical practices, early patient discharge has become a priority for hospitals and physicians alike. However, the impact of surgery start time on the ability for same-day discharge has not been explored in spine surgery. METHODS: A surgical database of patients who underwent ACDF from 2013 to 2015 was reviewed. Patients were stratified into two cohorts: those whose surgery was the first of the day (early cohort), and those who underwent later surgeries. Baseline patient characteristics and perioperative variables were compared between cohorts using Student t test and χ test. Same-day discharge was tested for association with surgical start time using Poisson regression with robust error variance controlling for preoperative variables. RESULTS: A total of 106 patients, divided into early and late cohorts of 60 and 46 patients, respectively, were included in the analysis. There were no significant differences in pre- or perioperative characteristics between cohorts (). Same-day discharge was achieved in 36.8% (n = 39) of all ACDF patients. The later cohort was significantly more likely to require an overnight stay compared with the early cohort (RR = 1.61 ±â€Š0.30; P = 0.010).(Table is included in full-text article.)CONCLUSION.: Patients undergoing ACDF later in the day are at a higher risk for staying overnight than those who have the first surgery of the day. These results may influence operative scheduling, as performing ACDFs early in the day may result in a greater likelihood of same-day discharge, eliminating the increased resource utilization associated with an overnight hospital stay. LEVEL OF EVIDENCE: 4.

Anterior Cervical Discectomy and Fusion: The Surgical Learning Curve.

STUDY DESIGN: Case-series OBJECTIVE.: The aim of the study was to investigate changes in intraoperative and postoperative parameters associated with the surgical learning curve for anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: ACDF is a common surgical spine procedure. The surgical learning curve for this procedure has not been previously characterized. METHODS: A prospectively maintained surgical database of consecutive patients who underwent primary 1-2 level ACDF for degenerative spine disease from 2006 to 2014 was reviewed. Patients with concurrent or revision procedures were excluded. The series began after the surgeon's fellowship and includes his first case as an attending. A total of 374 patients were divided sequentially into cohorts of 125 (early), 125 (middle), and 124 (late). Statistical analyses utilized independent sample t tests, chi squared tests, and multivariate regression adjusted for preoperative characteristics. The learning curve of operative time was characterized using three-parameter asymptotic regression and two separate linear regressions. RESULTS: The earliest cohort had a greater comorbidity burden, percentage of smokers, and Medicare patients, with fewer workers' compensation patients when compared to later cohorts. Later cohorts demonstrated decreased mean operative time and estimated blood loss (EBL) and increased arthrodesis rate. Asymptotic and linear regression analyses demonstrated that 50% of the learning curve occurred at case 17 and 31, respectively, whereas 90% of potential improvement occurred by case 56 and 57, respectively. CONCLUSION: A significant learning curve exists for surgeons performing ACDFs. Patients undergoing ACDF will experience shorter operations, less EBL, and greater arthrodesis rates as the surgeon gains experience. Operative proficiency can be expected to occur by case 60, with arthrodesis rate increasing over a longer period. These results suggest that despite longer operative times and increased EBL with earlier cases, ACDF can safely and effectively be performed at the onset of a surgeon's career. This conclusion may be useful to new surgeons debating between operative and nonoperative management of cervical degenerative disc disease. LEVEL OF EVIDENCE: 4.

Malnutrition Predicts Infectious and Wound Complications Following Posterior Lumbar Spinal Fusion.

STUDY DESIGN: A retrospective review of data collected prospectively by the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). OBJECTIVE: The aim of this study was to investigate the association between preoperative hypoalbuminemia, a marker for malnutrition, and complications during the 30 days following posterior lumbar fusion surgery. SUMMARY OF BACKGROUND DATA: Malnutrition is a potentially modifiable risk factor that may contribute to complications following spinal surgery. Although prior studies have identified associations between malnutrition, delayed wound healing, and surgical site infection (SSI), the evidence for such a relationship within spine surgery is mixed. METHODS: Patients who underwent posterior lumbar spinal fusion of one to three levels as part of the ACS-NSQIP were identified. Patients without preoperative serum albumin concentration were excluded. Outcomes were compared between patients with and without hypoalbuminemia (defined as serum albumin concentration <3.5 g/dL). All comparisons were adjusted for baseline differences between populations. RESULTS: Four thousand three hundred ten patients were included. The prevalence of hypoalbuminemia was 4.8%. In comparison to patients with normal albumin concentration, patients with hypoalbuminemia had a higher risk for occurrence of wound dehiscence [1.5% vs. 0.2%, adjusted relative risk (RR) = 5.8, P = 0.006], SSI (5.4% vs. 1.7%, adjusted RR = 2.3, P = 0.010), and urinary tract infection (5.4% vs. 1.5%, adjusted RR = 2.5, P = 0.005). Similarly, patients with hypoalbuminemia had a higher risk for unplanned hospital readmission within 30 days of surgery (11.7% vs. 5.4%, RR = 1.8, P < 0.001). Finally, patients with hypoalbuminemia had a longer mean inpatient stay (5.2 vs. 3.7 days, RR = 1.2, P < 0.001). CONCLUSION: The present study suggests that malnutrition is an independent risk factor for infectious and wound complications following posterior lumbar fusion. Malnutrition was also associated with an increased length of stay and readmission. Future studies should evaluate methods of correcting malnutrition before lumbar spinal surgery. Such efforts have the potential to meaningfully decrease the rates of adverse events following this procedure. LEVEL OF EVIDENCE: 3.

Effects of Intraoperative Anesthetic Medications on Postoperative Urinary Retention After Single-Level Lumbar Fusion.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: The aim of the study was to identify medications that may potentially contribute to developing postoperative urinary retention (POUR) after lumbar spinal fusion procedures. SUMMARY OF BACKGROUND DATA: POUR is a concerning event that may occur after routine orthopedic surgery. The relation between intraoperative medications and POUR after lumbar spine surgery has not been well characterized. METHODS: A prospectively maintained database of patients who underwent a primary single-level, minimally invasive transforaminal lumbar interbody fusion between 2009 and 2013 was reviewed. POUR was defined as a bladder scan of 300 mL or higher, the postoperative necessity of a straight catheterization, or a urology consult for urinary retention. The use and dose-response of intraoperative medications between patients with and without POUR were compared. Potential risk factors for developing POUR were analyzed using multivariate analysis. RESULTS: A total of 205 patients were included in the study, 17% of whom experienced POUR (n = 34). Administration of phenylephrine and neostigmine was associated with POUR (phenylephrine: 32.3% vs. 13.8%, P = 0.017; neostigmine: 19.5% vs. 6.5%, P = 0.042). Parametric analysis demonstrated an association of increasing dose of neostigmine with POUR (4.66 vs. 4.22 mg, P = 0.023). Similarly, a nonparametric analysis demonstrated an association of increasing doses of both neostigmine and phenylephrine with POUR (neostigmine: 4.25 vs. 3.16 mg, P = 0.02; phenylephrine: 105.88 vs. 40.64 mg, P = 0.008). CONCLUSION: Approximately 20% of patients may develop POUR after routine lumbar spine surgery. The use of certain intraoperative anesthetics such as phenylephrine and neostigmine is strongly associated with the development of POUR postoperatively. This finding suggests that there may be modifiable anesthetic risk factors to prevent the development of POUR in patients undergoing lumbar spine surgery. Future prospective, controlled studies specifically addressing these findings could lead to improved patient care and decreased healthcare costs. LEVEL OF EVIDENCE: 4.

Multimodal Versus Patient-Controlled Analgesia After an Anterior Cervical Decompression and Fusion.

STUDY DESIGN: Retrospective analysis of a prospectively maintained surgical registry. OBJECTIVE: To compare postoperative narcotic consumption between multimodal analgesia (MMA) and patient-controlled analgesia (PCA) after an anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Studies suggest that a multimodal approach to pain management leads to decreased pain and morphine consumption after total joint arthroplasty and lumbar spinal procedures. Patients and surgeons would benefit from knowing whether a multimodal approach to pain management is superior to PCA for ACDF. METHODS: A retrospective cohort study of ACDF patients receiving either MMA or PCA was conducted. Inpatient narcotic consumption, pain scores, nausea/vomiting, hospital length of stay, and narcotic dependence during the months after surgery were compared between MMA and PCA. RESULTS: A total of 239 patients met inclusion criteria. Of these, 55 (23.0%) received MMA and 184 (77.0%) received PCA. Patients who received MMA had a lower rate of inpatient narcotic consumption (2.5 OME/h vs. 5.8 OME/h, P < 0.001) were less likely to experience nausea/vomiting during the hospitalization (5.5% vs. 37.5%, P < 0.001), and had a shorter hospital length of stay (27.3 vs. 40.1 h, P < 0.001). However, there was no difference between groups in mean visual analogue pain scale during postoperative day zero (4.7 for MMA vs. 5.2 for PCA, P = 0.126) or during postoperative day one (4.1 for MMA vs. 4.1 for PCA, P = 0.937). In addition, there was no difference in the rate of narcotic dependence at the first (P = 0.626) or second (P = 0.480) postoperative visits. CONCLUSION: These data suggest that MMA results in lower narcotic consumption than PCA after an ACDF. This difference is associated with a shorter inpatient stay and a decrease in postoperative nausea/vomiting. Critically, MMA and PCA appear to provide similar postoperative analgesia. LEVEL OF EVIDENCE: 3.