Dante M. Leven

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

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

Frailty is associated with morbidity in adults undergoing elective anterior lumbar interbody fusion (ALIF) surgery

BACKGROUND CONTEXT Prior studies have suggested no significant differences in functional status and postoperative complications of elderly versus nonelderly patients undergoing posterior lumbar interbody fusion; however, similar studies have not been comprehensively investigated in the setting of anterior lumbar interbody fusion (ALIF). PURPOSE The objective was to quantify the ability of the modified Frailty Index (mFI) to predict postoperative events in patients undergoing ALIF. STUDY DESIGN Secondary analysis of prospectively collected data. PATIENT SAMPLE Patients undergoing ALIF in the National Surgical Quality Improvement Program (NSQIP) participant files for the period 2010 through 2014. OUTCOMES MEASURES Outcome measures included any postoperative complication, return to operating room (OR), and length of stay >5 days. METHODS NSQIP participant files from 2010 to 2014 were used to identify patients undergoing ALIF. The mFI used in the present study is an 11-variable assessment that maps 16 NSQIP variables to 11 variables in the Canadian Study of Health and Ageing Frailty Index. Univariate analysis and multivariable logistic regression models were used to compare the relative strength of association between mFI with outcome variables of interest. RESULTS In total, 3,920 ALIF cases were identified and grouped according to their mFI score: 0 (n=2,025), 0.09 (n=1,382), 0.18 (n=464), or ≥0.27 (n=49). As the mFI increased from 0 (no frailty-associated variables) to 0.27 (4 of 11) or higher, there was a significant stepwise increase in any complication from 10.8% to 32.7%. After multivariable regression analysis, no significant association was found between higher mFI scores with urinary tract infections and venous thromboembolism. High frailty scores were significant predictors of any complication (mFI of ≥0.27 [reference: 0]; OR 2.4; p=.040) and pulmonary complications (mFI score ≥0.27; OR 7.5; p=.001). CONCLUSIONS In summary, high mFI scores were found to be independently associated with any complication and pulmonary complications in patients who underwent ALIF. The use of mFI together with traditional risk factors may help better identify high-surgical risk patients, which may be useful for preoperative and postoperative care optimization.

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

Risk Factors for Reoperation in Patients Treated Surgically for Lumbar Stenosis: A Subanalysis of the 8-year Data From the SPORT Trial.

Study Design. A retrospective subgroup analysis was performed on surgically treated patients from the lumbar spinal stenosis (SpS) arm of the Spine Patient Outcomes Research Trial (SPORT), randomized, and observational cohorts. Objective. To identify risk factors for reoperation in patients treated surgically for SpS and compare outcomes between patients who underwent reoperation with those who did not. Summary of Background Data. SpS is one of the most common indications for surgery in the elderly; however, few long-term studies have identified risk factors for reoperation. Methods. A post-hoc subgroup analysis was performed on patients from the SpS arm of the SPORT, randomized and observational cohorts. Baseline characteristics were analyzed between reoperation and no-reoperation groups using univariate and multivariate analysis on data 8 years postoperation. Results. Of the 417 study patients, 88% underwent decompression only, 5% noninstrumented fusion, and 6% instrumented fusion. At the 8-year follow-up, the reoperation rate was 18%; 52% of reoperations were for recurrent stenosis or progressive spondylolisthesis, 25% for complication or other reason, and 16% for new condition. Of patients who underwent a reoperation, 42% did so within 2 years, 70% within 4 years, and 84% within 6 years. Patients who underwent reoperation were less likely to have presented with any neurological deficit (43% reop vs. 57% no reop, P = 0.04). Patients improved less at follow-up in the reoperation group (P < 0.001). Conclusion. In patients undergoing surgical treatment for SpS, the reoperation rate at 8-year follow-up was 18%. Patients with a reoperation were less likely to have a baseline neurological deficit. Patients who did not undergo reoperation had better patient reported outcomes at 8-year follow-up compared with those who had repeat surgery. Level of Evidence: 2

Hospital Acquired Conditions (HACs) in Adult Spinal Deformity Surgery: Predictors for HACs and Other 30-day Postoperative Outcomes.

Study Design. A retrospective study of prospectively collected data. Objective. The aim of this study was to identify risk factors in developing hospital-acquired conditions (HACs) and association of HACs with other 30-day complications in the adult spinal deformity (ASD) population. Summary of Background Data. HACs are subject to a nonpayment policy by the Center for Medicare and Medicaid Services and provide an incentive for medical institutions to improve patient safety. HACs in the ASD population may further exacerbate the already high rates of postoperative morbidity and mortality. Methods. The 2010 to 2014 ACS-NSQIP database was queried using Current Procedural Terminology (CPT) codes for adults who had fusion for spinal deformity. Patients were divided into two cohorts on the basis of the development of an HAC, as defined as a case of surgical site infection, urinary tract infection, or venous thromboembolism. Univariate and multivariate logistic regression analyses were employed to determine predictors for HACs and association of HACs with other 30-day postoperative outcomes. Results. Five thousand eight hundred nineteen patients met the inclusion criteria for the study of whom 313 (5.4%) had an HAC. Multivariate logistic regression analysis revealed that age 61 to 70 versus ⩽50 years [odds ratio (OR) = 1.58, 1.10–2.27, P = 0.013], 71 to 80 versus ⩽50 years (OR = 1.94, 1.31–2.87, P = 0.001), and >80 versus ⩽50 years (OR = 2.30, 1.21–4.37, P = 0.011), dependent/partially dependent versus independent functional status (OR = 1.74, 1.13–2.68, P = 0.011), combined versus anterior surgical approach (OR = 2.46, 1.43–4.24, P = 0.001), and posterior versus anterior surgical approach (OR = 1.64, 1.19–2.25, P = 0.002), osteotomies (OR = 1.61, 1.22–2.13, P = 0.001), steroid use (OR = 2.19, 1.39–3.45, P = 0.001), obesity (OR = 1.38, 1.09–1.74, P = 0.007), and operation time ≥4 hours (OR = 2.42, 1.82–3.21, P < 0.001) were predictive factors in developing an HAC. Conclusion. Several modifiable and nonmodifiable factors (age, functional status, surgical approach, utilization of osteotomies, steroid use, obesity, and operation time ≥4 hours) were associated with developing an HAC. HACs were also risk factors for other postoperative complications. Level of Evidence: 3

The 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 studys findings of potentially modifiable risk factors suggest that substantial improvement with this quality metric is possible. Level of Evidence:N/A

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

Pseudarthrosis of the Cervical Spine: Risk Factors, Diagnosis and Management

Cervical myelopathy and radiculopathy are common pathologies that often improve with spinal decompression and fusion. Postoperative complications include pseudarthrosis, which can be challenging to diagnose and manage. We reviewed the literature with regard to risk factors, diagnosis, controversies, and management of cervical pseudarthrosis.

Comparing National Inpatient Sample and National Surgical Quality Improvement Program: An Independent Risk Factor Analysis for Risk Stratification in Anterior Cervical Discectomy and Fusion

Study Design. Retrospective study of prospectively collected data. Objective. To explore interdatabase reliability between National Inpatient Sample (NIS) and National Surgical Quality Improvement Program (NSQIP) for anterior cervical discectomy and fusion (ACDF) in data collection and its impact on subsequent statistical analyses. Summary of Background Data. Clinical studies in orthopedics using national databases are ubiquitous, but analytical differences across databases are largely unexplored. Methods. A retrospective cohort study of patients undergoing ACDF surgery was performed in NIS and NSQIP. Key demographic variables, comorbidities, intraoperative characteristics, and postoperative complications were analyzed via bivariate and multivariate analyses. Results. A total of 112,162 patients were identified from NIS and 10,617 from NSQIP. Bivariate analysis revealed small, but significant, differences between patient demographics, whereas patient comorbidities and ACDF intraoperative variables were largely much more distinct across the two databases. Multivariate analysis identified independent risk factors between NIS and NSQIP for mortality, cardiac complications, and postoperative sepsis, some of which were identified in both but most of which were unique to one database. Identification of independent risk factors from both databases specifically highlights their greater validity and importance in stratifying patient risks. In addition, NSQIP was found to be a more accurate predictor for complications based on the average areas under the receiver-operating curve (CNSQIP = 0.83 vs. CNIS = 0.81) across the multivariate models. Complication rate analysis between inpatient and outpatient settings in NSQIP showed the importance of at least 30-day patient follow up, which was devoid in NIS data tabulation and further marked its weakness compared with NSQIP. Conclusion. Despite having largely similar patient demographics, this study highlights critical risk factors for ACDF and demonstrates how different patient profiles can be across NIS and NSQIP, the impact of such differences on identification of independent risk factors, and how NSQIP is ultimately better suited for adverse-event studies. Level of Evidence: 3