Enhanced Risk Stratification for Short-Term Complications Following Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures.

BACKGROUND: For patients with back pain from osteoporotic vertebral compression fractures (VCFs), vertebral augmentation remains the most utilized surgical intervention. Previous studies report 30-day readmission and mortality rates of up to 10% and 2%, respectively. These studies, however, have included patients with pathologic fractures and combined patients in different admission settings. We undertook the current study to address such shortcomings, which make risk stratification and appropriate counseling difficult. METHODS: Four consecutive years of the National Surgical Quality Improvement Program database were queried. Patients who underwent vertebral augmentation for osteoporotic VCFs were divided into 3 groups: (1) outpatient group (defined as patients with same-day discharge), (2) inpatient group (defined as those who were admitted postoperatively), and (3) preprocedure hospitalized group (defined as those who were already inpatient or were at acute/intermediate care facilities and transferred). Postoperative 30-day complications and readmission rates were compared between different groups and examined using multivariate analyses. RESULTS: A total of 1023 patients underwent outpatient surgery; 503 were admitted on the day of surgery; and 149 patients were already in-hospital or were transferred from other facility. Mortality rates were 0.68%, 0.60%, and 2.68%, and readmission rates were 6.26%, 6.76%, and 12.8%, for outpatient, inpatient, and preprocedure hospitalization cohorts, respectively. Multivariate analyses identified preprocedure hospitalization as an independent risk factor for urinary tract infection (UTI; OR = 3.98, 95% CI = 1.41-11.20, P = 0.028), pneumonia (OR = 19.69, 95% CI = 3.81-101.65, P < 0.001), readmission (OR = 1.86, 95% CI = 1.06-3.26, P = 0.032), and mortality (OR = 4.49, 95% CI = 1.22-16.53, P = 0.024). CONCLUSION: Our findings suggest that published rates of complications and mortality are substantially impacted by the cohort of patients who are already hospitalized or transferred from other facilities. Such patients are at a higher risk of UTI, pneumonia, readmission, and mortality. Conversely, we show that a relatively healthy patient being offered outpatient same-day augmentation has a readmission risk 40% lower and a mortality risk 3 times lower than previously reported.

Efficacy and safety of intrawound antibiotics in patients undergoing posterior spinal fusion for adolescent idiopathic scoliosis: a nationwide database study.

PURPOSE: To assess the efficacy and safety of intrawound antibiotics in posterior fusions for adolescent idiopathic scoliosis (AIS). METHODS: The NSQIP-Pediatric databases 2016-2018 were utilized. Patients 10 years of age or older with AIS who underwent posterior fusion were selected and divided into two cohorts based on the receipt of intrawound antibiotics. Patient characteristics and complications were compared. Multivariate analyses were performed to determine the efficacy and safety of intrawound antibiotics. RESULTS: A total of 4203 patients received intrawound antibiotics while 879 patients did not. The intrawound antibiotic group had longer constructs, higher blood loss, and longer operative times, factors historically associated with higher infection rates. Those that received intrawound antibiotics had SSI rate of 0.69%, while its counterpart had 0.57% (p = 0.689). The reoperation rates were 1.12% and 1.25% (p = 0.735), for those with and without intrawound antibiotics, respectively. In multivariate analyses, intrawound antibiotics use was not found to be a significant predictor for SSI, any complications, reoperation and readmission. CONCLUSION: The current study represents the largest AIS surgery cohort studied to evaluate the efficacy of intrawound antibiotics. Our analysis failed to demonstrate association between the use of intrawound antibiotics and reduction in SSI. While other studies have reported seroma, wound dehiscence and renal failure with the practice, we did not observe an increased rate of such complications. This study highlights the difficulty of understanding the role for individual infection prevention measures in current surgical settings, where the SSI rate for the control group was substantially lower than 1%.

Micromonas micros: A rare anaerobic cause of late implant failure following spinal surgery.

Context: Delayed, postoperative, spine infections are rare, most commonly occurring secondary to fastidious, less virulent pathogens. The etiology may involve a distant infectious focus, not related to the index operation. Patients may present months, or even years postoperatively with pain related to mechanical implant failure, often without additional signs of systemic infection.Findings: We present the case of a 59-year-old male who developed rapid disk degeneration and implant failure seven months following instrumented lumbar fusion surgery. The causal organism was found to be Micromonas micros, an anaerobic bacterium typically located in the oral cavity and associated with periodontal disease. The patient was found to have extensive oral caries, which were presumed to have occurred secondary to poor oral hygiene and his use of fentanyl lozenges for chronic back pain. The patient was treated with revision staged spinal surgery and long-term intravenous antibiotics.Conclusion/clinical relevance: This case highlights an unusual etiology of delayed postoperative spinal implant failure and provides evidence for periodontal disease as a source of hematogenous seeding in postoperative spinal infections. The orthopaedist should also be aware of the potential relationship between poor oral hygiene and the use of high sugar content fentanyl lozenges in treating chronic back pain in these patients.

Thirty-Day Perioperative Complications, Prolonged Length of Stay, and Readmission Following Elective Posterior Lumbar Fusion Associated With Poor Nutritional Status.

STUDY DESIGN: Retrospective study. OBJECTIVE: To determine the rates of early postoperative mortality and morbidity in adults with hypoalbuminemia undergoing elective posterior lumbar fusion (PLF). METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) was examined from 2005 to 2012. Current Procedural Terminology (CPT) codes were used to query the database for adults (≥18 years) who underwent PLF and/or posterior/transforaminal lumbar interbody fusion (PLIF/TLIF). Patients were divided into those with normal albumin concentration (≥3.5g/dL) and those with hypoalbuminemia (<3.5 g/dL). Both univariate and multivariate analyses were performed. RESULTS: A total of 2410 patients were included, of whom 2251 (93.4%) were normoalbuminemic and 159 (6.6%) were hypoalbuminemic. Patients with preoperative serum albumin levels <3.5 g/dL were older with a higher American Society of Anesthesiologists (ASA) score, and more comorbidities, including anemia, diabetes, dependent functional status, and preoperative history of chronic steroid therapy. Hypoalbuminemic patients had higher rates of any 30-day perioperative complication (P < .001), unplanned readmission (P = .019), and prolonged length of stay (LOS) >5 days (P < .001). However, hypoalbuminemia was not significantly associated with any specific perioperative complication. On multivariate analysis, preoperative hypoalbuminemia was found to be an independent predictor of prolonged LOS (OR 2.4, 95% CI 1.7-3.5; P < .001) and unplanned readmission (OR 2.7, 95% CI 1.1-6.3; P = .023). CONCLUSION: Hypoalbuminemia was found to be an important predictor of patient outcomes in this population. This study suggests that clinicians should consider nutritional screening and optimization as part of the preoperative risk assessment algorithm. LEVEL OF EVIDENCE: III.

Short-Term Complications of Anterior Fixation of Odontoid Fractures.

STUDY DESIGN: Retrospective study. OBJECTIVE: Anterior fixation of odontoid fracture has been associated with high morbidity and mortality in small, single institution series. Identifying risk factors may improve risk stratification and highlight factors that could be optimized preoperatively. The objective of this study was to determine the 30-day complication rate following anterior fixation of odontoid fractures and to identify associated risk factors among patients in a large national database. METHODS: Patients who underwent anterior fixation were identified in the American College of Surgeons National Quality Improvement Program database (ACS NSQIP) from 2007 to 2012. Patient demographics, medical comorbidities, perioperative complications, and postoperative complications up to 30 days were analyzed by univariate and multivariate analysis. RESULTS: Overall, 103 patients met criteria for the study. The average age was 73.9 years and patients were predominantly white (85.4%). Cardiac comorbidity was common (66.0%), as were dependent functional status (14.6%) and bleeding disorders (13.6%). Complications occurred in 37.9% of patients, and mortality was high (6.8%). Age, white race, and history of bleeding disorders were independently predictive of complications in the multivariate analysis. The postoperative hospital stay was >5 days for 45.6% of patients. CONCLUSION: In a large, multicenter database study, anterior fixation of odontoid fracture was associated with high morbidity and mortality. Although advanced age was associated with increased risk of complications, patients undergoing anterior fixation were older, on average, than in prior studies. Bleeding disorder was a potentially modifiable risk factor for complications that could be optimized prior to surgery.

Patient Factors Contributing to Prolonged Postoperative Length of Stay and Increased Rate of Readmission After Elective Posterior Cervical Fusion.

STUDY DESIGN: This is retrospective study of prospectively collected data. OBJECTIVE: To identify patient factors that are independently associated with prolonged length of stay (LOS) and readmission after posterior cervical fusion (PCF) utilizing a large national database. SUMMARY OF BACKGROUND DATA: A number of studies have investigated the morbidity and mortality after PCF; however, little is known about the factors that are associated with prolonged LOS and readmission, both of which incur increased costs for patients and hospitals. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2011 to 2014. Current Procedural Terminology code 22600 was used to identify patients who underwent PCF. All patient factors were assessed for association with LOS and readmission rate using bivariate and multivariate logistic regressions. RESULTS: A total of 2667 patients who underwent PCF met the inclusion criteria for LOS analysis. Average (±SD) LOS was 3.92 (±3.24) days, and median LOS was 3 days (interquartile range, 2-5 d). On multivariate analysis, increased LOS was found to be significantly associated with dependent functional status (P<0.001), diabetes mellitus (P=0.021), preoperative anemia (P=0.001), American Society of Anesthesiologists class 3 or 4 (P<0.001), and number of fused levels (P<0.001). A total of 2591 patients met criteria (LOS≤11 d) for analysis of readmission. Readmission rate among these patients was 7.1%. Average (±SD) LOS of the patients not readmitted within 30 days of operation was 3.89 (±3.25), whereas the average (±SD) LOS of the patients readmitted was 4.24 (±3.08). On multivariate analysis, readmission was found to be significantly associated with only dependent functional status (P=0.019) and increased number of fused levels (P=0.032). CONCLUSIONS: The current study provides valuable information on patient factors that are associated with prolonged LOS and readmission, which would be useful in enhanced informed consent before surgery, surgical planning, discharge planning, and optimizing postoperative care. LEVEL OF EVIDENCE: Level III.

Incidence and Risk Factors for 30-Day Unplanned Readmissions After Elective Posterior Lumbar Fusion.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To perform a multiinstitutional assessment on the incidence and risk factors for unplanned readmissions following elective posterior lumbar fusion (PLF) surgery. SUMMARY OF BACKGROUND DATA: Understanding what may drive rehospitalizations is a necessary step toward higher quality care. Identifying risk factors for unplanned readmission is especially important for elective PLF, which is a common procedure that is known to be associated with significant adverse events. METHODS: Adult patients undergoing PLF were identified using current procedure terminology (CPT) from the American College of Surgeons National Surgical Quality Improvement Program. Both descriptive and comparative statistics were performed for patient characteristics, clinical factors, and postoperative complications. Subsequently, a step-wise multivariate logistic regression was employed. RESULTS: Of the 2301 patients who met inclusion criteria for this study, 117 were unplanned readmissions (5.1%). These occurred at a mean of 15.9 days (range: 3-30 days) after surgery. The risk-adjusted analysis revealed that bleeding disorder (odds ratio, OR = 2.8, confidence intervals, CI = 1.0-7.6, P = 0.043), insulin dependent diabetes (OR = 2.5, CI = 1.4-4.4, P = 0.004), and total length of stay > 5 days (OR = 1.8, CI = 1.2-2.8, P = 0.009) were independent predictors for unplanned readmission. Significant postoperative complications included wound complications (OR = 27.6, CI = 13.9-54.8, P < 0.0001), pulmonary embolism and/or deep vein thrombosis/thrombophlebitis (OR = 11.9, CI = 5.0-28.5, P < 0.0001), sepsis (OR = 8.5, CI = 2.3-32.1, P = 0.002), and urinary tract infections (OR = 2.4, CI = 0.9-6.9, P = 0.094). CONCLUSION: The unplanned readmission rate for patients undergoing PLF was low, but this study's findings of potentially modifiable risk factors suggest that substantial improvement with this quality metric is possible. LEVEL OF EVIDENCE: N/A.

Frailty Is Predictive of Adverse Postoperative Events in Patients Undergoing Lumbar Fusion.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To analyze the modified frailty index (mFI) as a predictor of adverse postoperative events following posterior lumbar fusion. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database including all adult patients undergoing posterior lumbar interbody fusion or transforaminal lumbar interbody fusion between 2005 and 2012. Outcomes measured included mortality, postoperative complications, length of stay, reoperations, and readmissions. The previously described mFI was calculated, and univariate and multivariate logistic regression analysis were used to analyze risk factors associated with morbidity, mortality, and adverse postoperative events. This study was qualified as exempt by the Mount Sinai Hospital Institutional Review Board. RESULTS: A total of 6094 patients met inclusion criteria. The mean mFI was 0.087(0-0.545). Increasing mFI score was associated with increased complications, reoperations, prolonged length of stay (LOS), and morbidity (P < .05). As the mFI score increased from 0.27 (3/11 variables present) to ≥0.36 (4/11), the rate of any complication increased from 26.8% to 35% (P < .0001), sepsis 2.4% to 5.2% (P < .0001), wound complications 4.4% to 6.5% (P < .0001), unplanned readmissions 4.7% to 20% (P = .02), and urinary tract infection 4.1% to 10.4% (P < .0001). An mFI of ≥0.36 was an independent predictor of any complication (odds ratio [OR]= 2.2, 95% confidence interval [CI] = 1.3-3.7), sepsis (OR = 6.3, 95%, CI = 1.8-21), wound complications (OR = 2.9, 95% CI = 1.1-8.2), prolonged LOS (OR = 2.3, 95% CI = 1.4-3.7), and readmission (OR = 4.3, 95% CI = 1.5-12.7). CONCLUSION: Patients with higher mFI scores (≥ 4/11 variables) are at a significantly higher risk of major complications, readmissions, and prolonged LOS following lumbar fusion.

Incidence, Impact, and Risk Factors for 30-Day Wound Complications Following Elective Adult Spinal Deformity Surgery.

STUDY DESIGN: Case-control study. OBJECTIVE: To determine the incidence, impact, and risk factors for wound complications within 30 days following elective adult spinal deformity surgery. METHODS: Current Procedural Terminology and International Classification of Diseases, Ninth Edition, diagnosis codes were used to query the database for adults who underwent spinal deformity surgery from 2010 to 2014. Patients were separated into groups of those with and without wound complications. Univariate analysis and multivariate logistic regression were used to analyze the influence of patient factors, operative variables, and clinical characteristics on the incidence of postoperative wound complication. This study was qualified as exempt by the Mount Sinai Hospital Institutional Review Board. RESULTS: A total of 5803 patients met the criteria for this study. Wound complications occurred in 140 patients (2.4%) and were significantly associated with other adverse outcomes, including higher rates of unplanned reoperation (P < .0001) and prolonged length of stay (P < .0001). Regardless of fusion length, wound complication rates were higher with a posterior approach (short = 2.7%; long = 3.7%) than an anterior one (short = 2.2%; long = 2.7). According to the multivariate analysis, posterior fusion (odds ratio [OR] = 1.8; P = .010), obese class II (OR = 1.7; P = .046), obese class III (OR = 2.8; P < .0001), preoperative blood transfusion (OR = 6.1; P = .021), American Society of Anesthesiologists class ≥3 (OR = 1.7; P = .009), and operative time >4 hours (OR = 1.8; P = .006) were statistically significant risk factors for wound complications. CONCLUSION: The 30-day incidence of wound complication in adult spinal deformity surgery is 2.4%. The risk factors for wound complication are multifactorial. This data should provide a step toward developing quality improvement measures aimed at reducing complications in high-risk adults.

Early Complications and Outcomes in Adult Spinal Deformity Surgery: An NSQIP Study Based on 5803 Patients.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: The purpose of this study is to determine the incidence, impact, and risk factors for short-term postoperative complications following elective adult spinal deformity (ASD) surgery. METHODS: Current Procedural Terminology codes were used to query the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) for adults who underwent spinal deformity surgery from 2010 to 2014. Patients were separated into groups of those with and without complications. Univariate analysis and multivariate logistic regression were used to assess the impact of patient characteristics and operative features on postoperative outcomes. RESULTS: In total, 5803 patients were identified as having undergone ASD surgery in the NSQIP database. The average patient age was 59.5 (±13.5) years, 59.0% were female, and 81.1% were of Caucasian race. The mean body mass index was 29.5(±6.6), with 41.9% of patients having a body mass index of 30 or higher. The most common comorbidities were hypertension requiring medication (54.5%), chronic obstructive pulmonary disease (4.9%), and bleeding disorders (1.2%). Nearly a half of the ASD patients had an operative time >4 hours. The posterior fusion approach was more common (56.9%) than an anterior one (39.6%). The mean total relative value unit was 73.4 (±28.8). Based on multivariate analyses, several patient and operative characteristics were found to be predictive of morbidity. CONCLUSION: Surgical correction of ASD is associated with substantial risk of intraoperative and postoperative complications. Preoperative and intraoperative variables were associated with increased morbidity and mortality. This data may assist in developing future quality improvement activities and saving costs through measurable improvement in patient safety.

Impact of Gender on 30-Day Complications After Primary Total Joint Arthroplasty.

BACKGROUND: Impact of gender on 30-day complications has been investigated in other surgical procedures but has not yet been studied in total hip arthroplasty (THA) or total knee arthroplasty (TKA). METHODS: Patients who received THA or TKA from 2012 to 2014 were identified in the National Surgical Quality Improvement Program database. Patients were divided into 2 groups based on gender. Bivariate and multivariate analyses were performed to assess associations between gender and patient factors and complications after THA or TKA and to assess whether gender was an independent risk factor. RESULTS: THA patients consisted of 45.1% male and 54.9% female. In a multivariate analysis, female gender was found to be a protective factor for mortality, sepsis, cardiovascular complications, unplanned reintubation, and renal complications and as an independent risk factor for urinary tract infection, blood transfusion, and nonhome discharge after THA. TKA patients consisted of 36.7% male and 62.3% female. Multivariate analysis revealed female gender as a protective factor for sepsis, cardiovascular complications, and renal complications and as an independent risk factor for urinary tract infection, blood transfusion, and nonhome discharge after TKA. CONCLUSION: There are discrepancies in the THA or TKA complications based on gender, and the multivariate analyses confirmed gender as an independent risk factor for certain complications. Physicians should be mindful of patient's gender for better risk stratification and informed consent.

Frailty Index as a Predictor of Adverse Postoperative Outcomes in Patients Undergoing Cervical Spinal Fusion.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To investigate the applicability of the modified frailty index (mFI) as a predictor of adverse postoperative events in patients undergoing anterior cervical discectomy and fusion (ACDF) or posterior cervical fusion (PCF). SUMMARY OF BACKGROUND DATA: Prior studies have investigated the mFI and shown it as an independent predictor of adverse postoperative outcomes across multiple surgical specialties. However, this topic has not still been studied in patients undergoing cervical fusion or in spinal surgery. METHODS: The National Surgical Quality Improvement Program is a multicenter clinical registry that prospectively collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from about 400 hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent elective ACDF and PCF between 2005 and 2012. The mFI was calculated for each patient. Univariate analysis and multivariate logistic regression were used to analyze the mFI as a predictor for postoperative complications. RESULTS: For ACDF group, Clavien-Dindo grade IV complications rate increased from 0.8% to 9.0% as mFI increased from 0 to ≥0.27, and mFI = 0.27 was found to be an independent predictor of Clavien-Dindo grade IV complications (odds ratio, OR, = 4.67, 95% confidence interval, CI, = 2.27-9.62, P < 0.001). For PCF groups, Clavien-Dindo grade IV complications rate increased from 0.7% to 20.0% as mFI increased from 0 to ≥0.36, and mFI ≥ 0.36 was identified as an independent predictor of Clavien-Dindo grade IV complications (OR = 41.26, 95% CI = 6.62-257.15, P < 0.001). CONCLUSION: The mFI was shown to be an independent predictor of Clavien-Dindo grade IV complications in patients undergoing ACDF or PCF. The mFI itself may be used to stratify risks in patients undergoing cervical fusion, or, the mFI scheme could be used as a platform upon which more efficient risk stratification could be done with addition of other variables. LEVEL OF EVIDENCE: 4.

Increased risk of 30-day postoperative complications for diabetic patients following open reduction-internal fixation of proximal humerus fractures: an analysis of 1391 patients from the American College of Surgeons National Surgical Quality Improvement Program database.

BACKGROUND: Prior database studies have shown that complication rates following surgical treatment of proximal humerus fractures are low. However, diabetes has been shown across orthopedics to have significantly increased risks of postoperative complications. The purpose of our study was to identify complications for which diabetic patients are at increased risk following operative treatment of proximal humerus fractures. METHODS: The National Surgical Quality Improvement Program database from 2005 to 2014 identified patients >18 years undergoing open reduction-internal fixation for proximal humerus fractures. Patients with incomplete perioperative data were excluded. Patients with non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM) were compared with nondiabetic patients using multivariate logistic regression analysis. Odds ratio (OR) was calculated with a 95% confidence interval, and the significance level was held at P < .05. RESULTS: There were 1391 patients identified; 1147 (82%) were not diabetic, 91 (7%) had IDDM, and 153 (11%) had NIDDM. Of these, 39.68% (550) were obese (body mass index >30.0). Hypertension, dyspnea, and chronic obstructive pulmonary disease were the most frequent concurrent patient factors in diabetic patients. Postoperatively, patients with diabetes had a statistically significant higher risk of pneumonia (OR, 217.80; P = .002) and length of stay >4 days (OR, 2.05; P = .010). Among diabetics, non-insulin-dependent diabetics had a greater risk of sepsis (OR, 25.84; P = .022) and pneumonia (OR, 12.19; P = .013) than insulin-dependent diabetics. CONCLUSION: Both NIDDM and IDDM were associated with a number of adverse postoperative events. Importantly, NIDDM was found to be an independent risk factor for postoperative sepsis and pneumonia, whereas IDDM was identified as an independent risk factor for pneumonia and prolonged length of stay (≥4 days).

Impact of Glycemic Control on Morbidity and Mortality in Adult Idiopathic Scoliosis Patients Undergoing Spinal Fusion.

STUDY DESIGN: This is a retrospective analysis of administrative database. OBJECTIVE: To elucidate the effect of glycemic control on surgical outcomes of middle-aged and elderly idiopathic scoliosis patients undergoing spinal fusion surgery. SUMMARY OF BACKGROUND DATA: Diabetes mellitus (DM) is a condition thought to adversely affect outcomes of spine surgery. However, no study has stratified glycemic control levels and their impact on outcome for idiopathic scoliosis patients receiving a spinal fusion surgery. Previous studies may have reported higher than true rates of complications for controlled diabetic patients, who are the majority of diabetic patients. MATERIALS AND METHODS: The Nationwide Inpatient Sample was queried from years 2002 to 2011. We extracted idiopathic scoliosis patients older than 45 years of age that received spinal fusion and analyzed complications and outcomes variables among 3 cohorts: nondiabetic patients, controlled diabetics, and uncontrolled diabetics. Multivariate analyses were used to assess whether glycemic control was a risk factor for adverse postoperative outcomes. RESULTS: Controlled diabetics had significantly increased rates of acute renal failure (ARF), while uncontrolled diabetics had significantly increased rates of acute postoperative hemorrhage. In multivariate analyses controlling for patient factors and comorbidities, controlled DM was found to be an independent predictor of ARF [odds ratio (OR), 1.863; 95% confidence interval (CI), 1.346-2.579; P=0.0002), and uncontrolled DM was found to be a significant risk factor for acute postoperative hemorrhage (OR, 2.182; 95% CI, 1.192-3.997; P=0.0115), ARF (OR, 4.839; 95% CI, 1.748-13.392; P=0.0024), deep vein thrombosis (OR, 5.825; 95% CI, 1.329-25.522, P=0.0194) and in-patient mortality (OR, 8.889; 95% CI, 1.001-78.945; P=0.0499). CONCLUSIONS: Controlled DM was found to be a risk factor for ARF in adult idiopathic scoliosis patients undergoing spinal fusion surgery, while uncontrolled DM was shown to be a risk factor for postoperative hemorrhage, ARF, deep vein thrombosis, and mortality. The present study provides valuable data for better informed consent for patients with diabetes considering surgery for idiopathic scoliosis. LEVEL OF EVIDENCE: Level III.

Frailty Index Is a Significant Predictor of Complications and Mortality After Surgery for Adult Spinal Deformity.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To determine if the modified Frailty Index (mFI) could be used to predict postoperative complications in patients undergoing surgery for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: Surgery for patients with ASD is associated with high complication rates and significant concerns present during risk stratification with older patients. The mFI is an evaluation tool to describe the frailness of an individual and how their preoperative status may impact postoperative survival and outcomes. Using a large nationwide database, we assessed the utility of this instrument in patients undergoing surgery for ASD. METHODS: The American College of Surgeons National Surgical Quality Improvement Program is a large multicenter clinical registry that prospectively collects preoperative variables, patient demographics, operative factors, and 30-day postoperative morbidity and mortality outcomes from about 400 hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent fusion for spinal deformity. The previously described mFI was calculated based on the number of positive factors and univariate and multivariate logistic regression analysis were used to analyze the risk factors associated with mortality. RESULTS: Overall, 1001 patients were identified and the mean mFI score was 0.09 (range: 0-0.545). Increasing mFI score was associated with higher complication, reoperation, and mortality rates (P < 0.05). mFI of 0.09 and 0.18 was an independent predictor of any complication, mortality, requiring a blood transfusion, pulmonary embolism/deep vein thrombosis, and reoperation (all P < 0.05). In comparison with age >60 years obesity class III, mFI was a superior predictor of several postoperative complications and reoperation. CONCLUSION: Frailty was an independent predictor of postoperative complications, mortality, and reoperation in patients undergoing surgery for ASD. Preoperative assessment of the mFI in this patient population can be utilized to improve current risk models. LEVEL OF EVIDENCE: 3.

Simplified Frailty Index as a Predictor of Adverse Outcomes in Total Hip and Knee Arthroplasty.

BACKGROUND: The modified frailty index (mFI) has been shown to predict adverse outcomes in multiple nonorthopedic surgical specialties. This study aimed to assess whether mFI is a predictor of adverse events in patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Patients who underwent THA and TKA from 2005-2012 were identified in the National Surgical Quality Improvement Program database. mFI was calculated for each patient using 15 variables found in National Surgical Quality Improvement Program. Bivariate and multivariate analyses of postoperative adverse events, including Clavien-Dindo grade IV complications, were performed. RESULTS: A total of 14,583 THA and 25,223 TKA patients were included for analysis. The mean (standard deviation, range) mFIs were 0.083 (0.080, 0-0.55) for THA and 0.097 (0.080, 0-0.64) for TKA cohorts. On bivariate analyses, incidence of Clavien-Dindo grade IV complications (cardiac arrest, myocardial infarction, septic shock, pulmonary embolism, postoperative dialysis, reintubation, and prolonged ventilator requirement), hospital-acquired conditions (surgical site infection, venous thromboembolism, and urinary tract infection), any complications, and mortality increased significantly with increase in mFI (P < .0001 for all). Adjusting for demographics, age ≥ 75, body mass index ≥40, American Society of Anesthesiologists class ≥4, and nonclean wound status, mFI ≥0.45 was shown to be the strongest independent predictor of Clavien-Dindo grade IV complications for both THA and TKA cohorts with odds ratios of 5.140 and 4.183, respectively. CONCLUSION: mFI ≥0.45 is an independent predictor of Clavien-Dindo grade IV complications in TKA/THA patients with greater odds ratios than age >75, body mass index ≥40, American Society of Anesthesiologists class ≥4. mFI should be considered for risk stratifying joint arthroplasty patients preoperatively and perhaps determining immediate postoperative destination.

Impact of Resident Involvement on Morbidity in Adult Patients Undergoing Fusion for Spinal Deformity.

STUDY DESIGN: A retrospective study of prospectively collected data. OBJECTIVE: The aim of this study was to determine whether patients undergoing spinal deformity surgery with resident involvement are at an increased risk of morbidity. SUMMARY OF BACKGROUND DATA: Resident involvement has been investigated in other orthopedic procedures but has not been studied in adult spinal deformity surgery. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) is a large multicenter clinical registry that prospectively collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from about 400 hospitals nationwide. Current procedural terminology (CPT) codes were used to query the database for adults who underwent fusion for spinal deformity between 2005 and 2012. Patients were separated into propensity score matched groups of those with and without resident involvement. Univariate analysis and multivariate logistic regression were used to analyze the effect of resident involvement on the incidence of postoperative morbidity and other surgical outcomes. RESULTS: Resident involvement was an independent predictor of overall morbidity [odds ratio (OR) 2.2, P < 0.0001], wound complication (OR 2.5, P = 0.0252), intra-/postoperative transfusion (OR 2.3, P < 0.0001), and length of stay > 5 days (OR 2.0, P < 0.0001). However, resident involvement was not an independent predictor for other complications, such as mortality. CONCLUSION: Resident participation was associated with significantly longer operative times. As a result, higher rate of certain morbidity, but not mortality, was found, specifically for complications that have been previously associated with long operative duration. LEVEL OF EVIDENCE: 3.

Impact of Gender on 30-Day Complications After Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To determine if postoperative morbidity for patients undergoing spinal deformity surgery varies by sex. SUMMARY OF BACKGROUND DATA: Influence of sex has been investigated in other surgical procedures but has not yet been studied in adult spinal deformity surgery. METHODS: The American College of Surgeons National Surgical Quality Improvement Program is a large multicenter clinical registry that prospectively collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from about 400 hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent fusion for spinal deformity. Patients were separated into groups of male and female sex. Univariate analysis and multivariate logistic regression were used to analyze the effect of sex on the incidence of postoperative morbidity and mortality. RESULTS: Female sex was found to be a predictor of any complication[odds ratio (OR): 1.4, 95% confidence interval (CI) 1.2-1.7, P < 0.0001], intra- or postoperative RBC transfusion (OR: 1.6, 95% CI 1.4-1.9, P < .0001), urinary tract infection (OR: 2.0, 95% CI 1.2-3.3, P = 0.0046), and length of stay >5 days (OR: 1.3, 95% CI 1.1-1.5, P = 0.0015). Male sex was associated with higher rate of pulmonary (2.9% vs. 2.0%, P = 0.0344) and cardiac complications (0.9% vs. 0.5%, P = 0.0497). However, male sex as an independent risk factor for pulmonary (OR: 1.4, 95% CI 1.0-2.1, P = 0.0715) and cardiac complications (OR: 1.9, 95% CI 0.9-4.0, P = 0.1076) did not reach significance. CONCLUSION: Female sex was found to increase overall morbidity, particularly for urinary tract infection, transfusion, and length of stay >5 days. Male sex was associated with greater incidence of pulmonary and cardiac complications. Thus, sex and other patient characteristics highlighted must be considered as part of surgical risk planning and patient counseling. LEVEL OF EVIDENCE: 3.

Pediatric Cervical Spine and Spinal Cord Injury: A National Database Study.

STUDY DESIGN: A retrospective administrative database analysis. OBJECTIVE: The aim of this study was to investigate the incidence and characteristics of pediatric cervical spine injury (PCSI) utilizing the Kids' Inpatient Database (KID). SUMMARY OF BACKGROUND DATA: PCSI is debilitating, but comprehensive analyses have been difficult due to its rarity. There have been a few database studies on PCSI; however, the studies employed databases that suffer from selection bias. METHODS: The triennial KID was queried from years 2000 to 2012 using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Pediatric admissions were divided into five age groups reflecting different developmental stages. PCSI was analyzed in terms of trend, demographics, injury characteristics, hospital characteristics, comorbidities, and outcomes variables. Multivariate logistic regression analyses were used to identify independent risk factors for PCSI among trauma admissions and to identify independent risk factors for mortality among PCSI admissions. RESULTS: Over the past decade, the overall prevalence of traumatic PCSI was 2.07%, and the mortality rate was 4.87%. Most frequent cause of PCSI was transportation accidents, accounting for 57.51%. Upper cervical spine injury (C1-C4), cervical fracture with spinal cord injury, spinal cord injury without radiographic abnormality (SCIWORA), and dislocation showed a decreasing trend with age. Some comorbidities, including, but not limited to, fluid and electrolyte disorders, and paralysis were common across all age groups, while substance abuse showed a bimodal distribution. Independent risk factors for PCSI after trauma were older cohorts, non-Northeast region, and transportation accidents. For mortality after PCSI, independent risk factors were younger cohorts, transportation accidents, upper cervical spine injury, dislocation, and spinal cord injuries. Median length of stay and cost were 3.84 days and $14 742. CONCLUSION: Pediatric patients are highly heterogeneous, constantly undergoing behavioral, environmental, and anatomical changes. PCSI after trauma is more common among older cohorts; however, mortality after sustaining PCSI is higher among younger patients. LEVEL OF EVIDENCE: 4.

Proximal junctional kyphosis following adult spinal deformity surgery.

PURPOSE: Proximal junctional kyphosis (PJK) is a common radiographic finding following long spinal fusions. Whether PJK leads to negative clinical outcome is currently debatable. A systematic review was performed to assess the prevalence, risk factors, and treatments of PJK. METHODS: Literature search was conducted on PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials using the terms 'proximal junctional kyphosis' and 'proximal junctional failure'. Excluding reviews, commentaries, and case reports, we analyzed 33 studies that reported the prevalence rate, risk factors, and discussions on PJK following spinal deformity surgery. RESULTS: The prevalence rates varied widely from 6 to 61.7%. Numerous studies reported that clinical outcomes for patients with PJK were not significantly different from those without, except in one recent study in which adult patients with PJK experienced more pain. Risk factors for PJK included age at operation, low bone mineral density, shorter fusion constructs, upper instrumented vertebrae below L2, and inadequate restoration of global sagittal balance. CONCLUSIONS: Prevalence of PJK following long spinal fusion for adult spinal deformity was high but not clinically significant. Careful and detailed preoperative planning and surgical execution may reduce PJK in adult spinal deformity patients.