Double Sublaminal Band Passage Technique for Spinal Deformity Correction.

Sublaminar band fixation is a reliable way to anchor spinal rods to the vertebral column. This technique is especially useful when the anatomy precludes safe pedicle screw placement. Sublaminar bands allow for deformity correction and stabilization of the spine. One of the disadvantages of using the sublaminar band technique is the risk for neurologic injury during the passage of the band between the dura and lamina. In this article, we describe a new technique for passing sublaminar bands, i.e., the double sublaminar band passage technique. This technique decreases the number of passes against the dura, thereby decreasing the opportunity for neural injury. In addition, we present an illustrative case of an 11-year-old female with neuromuscular scoliosis who underwent a posterior spinal instrumented fusion with a hybrid screw and sublaminar band construct.

Does the Use of Locking Screws Decrease the Rate of Hardware Removal in Ankle Fractures?

Background. While biomechanical characteristics of locking screw fixation versus traditional plating has been studied extensively in orthopaedic literature, clinical outcome studies are lacking. The goal of this study was to evaluate the efficacy and complications rate of locking versus traditional nonlocking screws in complex ankle fractures employing distal fibula internal fixation with 1/3 semitubular small fragment plates. Methods. A retrospective review was performed between January 2010 and June 2013 of all patients in whom internal fixation of the fibula in an ankle fracture (open or closed) was performed using only 1/3 semitubular small fragment fibular plates. Patient characteristics, fracture patterns, specific screw choice that were placed in the most distal 2 fibular plate holes (either locking or nonlocking), infectious wound complications, and concomitant syndesmotic injury and the need and corresponding purpose for hardware removal were recorded. Results. A total of 135 patients were found to meet inclusion criteria and were analyzed for this study. Of the patients with locking screws, 25 of 98 (25%) elected to have hardware removed, while 13 of 37 (35%) of those with nonlocking screws elected hardware removal. This did not reach statistical significance (P = .30). There was no statistically significant difference between the groups with regards to age, smoking status, body mass index, diabetes, or use of syndesmotic screw fixation. There was no significant difference in loss of fixation, infection, or other surgical complications in between the groups. Conclusions. There was no significant decrease in the rate of hardware removal with the use of 1/3 tubular locking versus nonlocking plates in the treatment of distal fibula fractures. Despite these screws locking flush to the plate, the hardware is equally symptomatic in both groups. There was no significant difference in the rate of complications between the 2 groups and our data suggest that the added expense of using locking screws routinely when fixing lateral malleolar fractures should be carefully considered, especially if the fracture pattern does not warrant locking technology. Levels of Evidence: Prognostic, Level III.

Comparison of Direct Perioperative Costs in Treatment of Unstable Distal Radial Fractures: Open Reduction and Internal Fixation Versus Closed Reduction and Percutaneous Pinning.

BACKGROUND: As the United States transitions to value-based insurance, bundled payments, and capitated models, it is paramount to understand health-care costs and resource utilization. The financial implications of open reduction and internal fixation (ORIF) with a volar locking plate for management of unstable distal radial fractures have not been established. We aimed to elucidate cost differences between ORIF and closed reduction and percutaneous pinning (CRPP). Our hypothesis was that ORIF has greater direct perioperative costs than CRPP but that the costs equilibrate over time. METHODS: We reviewed financial data for 40 patients prospectively enrolled and randomized to undergo CRPP or ORIF for treatment of a closed, displaced, unstable distal radial fracture. Clinical and functional outcomes, hospital-associated direct perioperative costs, postoperative care and therapy costs, and costs for additional procedures were compared. Cost data were stratified into perioperative, 90-day, and 1-year periods, and were reported utilizing cost ratios (CRs) relative to the CRPP cohort. Statistical analysis was performed with chi-square and independent-samples t tests with an alpha level of <0.05. RESULTS: Seventeen patients underwent CRPP and 23 underwent ORIF with a volar plate. Patients who underwent ORIF incurred greater 90-day (CR = 2.03/1.0, p < 0.001) and 1-year (CR = 1.60/1.0, p < 0.001) direct costs than those who underwent CRPP. The differential was greatest in the immediate perioperative period and gradually decreased over time. Operating room fees (CR = 1.7/1.0, p < 0.001), operating room implants, anesthesia (CR = 1.8/1.0, p < 0.001), and total perioperative costs (CR = 2.7/1.0, p < 0.001) were significantly greater in the ORIF cohort. Rehabilitation and cast technician costs were comparable (CR = 0.9/1.0 [ORIF/CRPP], p = 0.69). At 1 year, the CR for all costs of decreased to 1.6/1.0 (ORIF/CRPP, p < 0.001). Compared with the CRPP cohort, the ORIF cohort demonstrated significantly better functional outcomes at 6, 9, and 12 weeks and similar outcomes at 1 year. CONCLUSIONS: ORIF for a displaced, unstable distal radial fracture incurred greater direct costs than CRPP. Although implant costs for ORIF provided the greatest cost differential, additional procedures and higher clinic costs in the CRPP cohort narrowed the 90-day and 1-year cost gaps. LEVEL OF EVIDENCE: Economic Level II. See Instructions for Authors for a complete description of levels of evidence.

Potential for Bias and the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scoring System.

BACKGROUND: The American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scoring System (AOFAS-AH) has not been validated and has significant risk for researcher bias, given that 40 out of 100 points are assessed by study staff subjectively. The purpose of this study is to evaluate its recent use in the orthopaedic literature to determine the percentage of previously published studies for which study conclusions would be changed if the AOFAS-AH scores were artificially altered, representing the effect of a systematic researcher bias. MATERIALS AND METHODS: Articles from January 2012 and February 2015 in three orthopaedic journals were queried for use of the AOFAS-AH. Quantities of 4, 8, or 12 points were added to or subtracted from mean AOFAS-AH scores for each study while otherwise maintaining the reported standard deviation to simulate a researcher bias when scoring the subjective sections. Statistical analysis was performed with the adjusted AOFAS-AH mean scores in order to elucidate a potential "reversal" in statistical significance and conclusion. RESULTS: A 1582 original research articles were published during this time period. 128 articles utilized the AOFAS-AH score. 30 articles (23.4%) reported the required statistical data to permit manipulation of AOFAS-AH scores. Nine of the 30 articles (30%) had a reversal following a manipulation of 12 or fewer points. Seven (5.5%) reported the blinding status of the researchers. CONCLUSION: The potential for bias is high with the AOFAS-AH and its continued is questionable. Researchers utilizing the AOFAS-AH should at a minimum appropriately blind study staff and consider pre-study clarification of subjective terminology. LEVELS OF EVIDENCE: Level IV.

Serial Mehta Cast Utilization in Infantile Idiopathic Scoliosis: Evaluation of Radiographic Predictors.

BACKGROUND: Mehta cast utilization has gained a considerable momentum as a nonoperative treatment modality for the initial management of infantile idiopathic scoliosis (IIS). Despite its acceptance, there is paucity of data that characterize the radiographic parameters associated with Mehta casting and the factors correlated with a sustained curve correction. METHODS: A retrospective review of IIS patients who underwent Mehta casting was performed with a mean 2-year follow-up. X-rays were evaluated at each visit for the Cobb angle, focal deformity, rib-vertebral angle difference, and height of concavity and convexity of the apical 3 vertebrae. Concave-to-convex height ratios were calculated and tracked for each patient. Radiographic parameters were compared from precasting to after final casting, and from final casting to most recent follow-up. RESULTS: A total of 45 patients were identified, of whom 18 (40%) were male and 27 (60%) were female, with a mean age of 18.8±9.5 months at first casting and a mean follow-up of 37.7±19.7 months. Following final casting, the mean Cobb angle (25.6 vs. 52.7 degrees), focal deformity (17.4 vs. 30.5 degrees), rib-vertebral angle difference (18 vs. 32.3 degrees), and the concave-to-convex height ratios improved relative to precast parameters, respectively (P<0.001). At final follow-up, mean Cobb angle (16.2 vs. 25.6 degrees) and concave-to-convex height ratios progressively improved when compared with final cast measurements, respectively (P<0.001). Five (11%) patients did not demonstrate sustained curve correction at final follow-up, whereas 4 (9%) required growing-rod placement. Lastly, the regression analysis demonstrated improvements in the focal deformity (17.4 vs. 30.5) and the concave-to-convex height ratios of the +1 and -1 apical vertebrae from the precast to last cast periods (P<0.001). These findings were correlated with sustained Cobb angle correction from cast removal to the most recent follow-up. CONCLUSIONS: Radiographic parameters associated with control of progressive deformity for IIS include improvements in focal deformity and concave-to-convex height ratios for +1 and -1 apical vertebrae after final casting. Mehta casting is an effective treatment for symptomatic IIS and continues to provide IIS patients with significant curve correction. LEVEL OF EVIDENCE: Level IV.

The utility of obtaining routine hematological laboratory values following an anterior cervical diskectomy and fusion.

STUDY DESIGN: Retrospective analysis of a prospectively maintained database. OBJECTIVE: To characterize the utility of obtaining routine postoperative laboratory studies after an anterior cervical diskectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: ACDF is typically associated with minimal blood loss and morbidity. However, at many institutions, postoperative laboratory studies are conducted routinely. This study aims to characterize the utility of these tests in the postoperative setting. METHODS: A retrospective analysis of a prospectively maintained database of 332 patients who underwent an ACDF for degenerative cervical spine disease between 2007 and 2014 was performed. Patients with a concurrent corpectomy, posterior fusion, or revision procedure were excluded. Patient demographics, comorbidities, visual analogue scale scores, surgical and hospitalization parameters, complications, and transfusion volumes were assessed. The patient's postoperative laboratory studies were compared with preoperative values. Statistical analysis was performed with independent sample T tests for continuous variables and χ analysis for categorical data. An α level of less than 0.05 denoted statistical significance. RESULTS: A total of 332 patients were included with a mean age of 51.1 ± 11.7 years. The overall mean procedural time, estimated blood loss, and length of stay were 60.0 ± 30.1 minutes, 69.4 ± 36.2 mL, and 40.2 ± 20.3 hours, respectively. Overall, 98.1% of patients demonstrated radiographical arthrodesis at 1 year. After a 1- or 2-level ACDF, the postoperative hemoglobin, hematocrit, blood urea nitrogen, sodium, and calcium levels significantly decreased, whereas glucose and chloride levels increased when compared with the preoperative values (P < 0.05). In addition, the 1-level ACDF cohort was also associated with reduced postoperative potassium level (P < 0.05). However, none of the patients required intraoperative or postoperative blood product transfusion or demonstrated evidence of postoperative anemia. Two patients (0.89%) required postoperative potassium replacement based upon laboratory values alone without clinical symptomatology. There were no complications that were related to the patient's hemodynamic status or fluid and electrolyte balance. CONCLUSION: In the majority of cases after an ACDF, no action was taken n the basis of the patient's routine postoperative laboratory data. None of the patients required blood product transfusion, whereas only 0.89% (n = 2) required potassium replacement for laboratory anomalies without clinical symptomatology. These findings suggest that routine postoperative complete blood counts do not change postoperative management after an ACDF unless intraoperative bleeding is noted or the patient carries risk factors for postoperative hemorrhagic anemia. LEVEL OF EVIDENCE: 3.

Does a kaolin-impregnated hemostatic dressing reduce intraoperative blood loss and blood transfusions in pediatric spinal deformity surgery?

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: To evaluate the hemostatic benefits of using a kaolin-impregnated dressing during pediatric spinal deformity correction surgery. SUMMARY OF BACKGROUND DATA: Minimizing blood loss and transfusions are clear benefits for patient safety. A technique common in both severe trauma and combat medicine that has not been reported in the spine literature is wound packing with a kaolin-impregnated hemostatic dressing. METHODS: Estimated blood loss and transfusion amounts were analyzed in a total of 117 retrospectively identified cases. The control group included 65 patients (46 females, 19 males, 12.7±4.5 yr, 10.2±4.8 levels fused) who received standard operative care with gauze packing between June 2007 and March 2010. The treatment group included 52 patients (33 females, 19 males, 13.9±3.2 yr, 10.4±4.3 levels fused) who underwent intraoperative packing with QuikClot Trauma Pads (QCTP, Z-Medica Corporation) for all surgical procedures from July 2010 to August 2011. No other major changes in the use of antifibrinolytics or perioperative, surgical, or anesthesia technique were noted. Statistical differences were analyzed using analysis of covariance in R with P value of less than 0.05. The statistical model included sex, age, weight, scoliosis type, the number of vertebral levels fused, and surgery duration as covariates. RESULTS: The treatment group had 40% less intraoperative estimated blood loss than the control group (974 mL vs. 1620 mL) (P<0.001). Patients who received the QCTP treatment also had 42% less total perioperative transfusion volume (499 mL vs. 862 mL) (P<0.01). CONCLUSION: The use of a kaolin-impregnated intraoperative trauma pad seems to be an effective and inexpensive method to reduce intraoperative blood loss and transfusion volume in pediatric spinal deformity surgery. LEVEL OF EVIDENCE: 3.

Point-counter-point debate: the association between recombinant human bone morphogenetic protein utilization and complications in spine surgery.

Bone morphogenetic proteins (BMPs) have been utilized in spine surgery for over 10 years as a bone graft substitute. Potential BMP-related adverse effects including retrograde ejaculation and heterotopic neuroforaminal bone formation have been described. Additionally, some studies have suggested an association between BMP and cancer. Inconsistencies exist in the published spine literature with regards to the incidence and association of complications with BMP utilization. In a point-counterpoint format, this article discusses the current evidence concerning the relationship between the utilization of BMP in spinal fusion and the risk of cancer, retrograde ejaculation (RE), neuroforaminal bone formation, and its role in anterior cervical spine surgery and adolescents.

Cost analysis of incidental durotomy in spine surgery.

STUDY DESIGN: Retrospective database analysis. OBJECTIVE: To characterize the consequences of an incidental durotomy with regard to perioperative complications and total hospital costs. SUMMARY OF BACKGROUND DATA: There is a paucity of data regarding how an incidental durotomy and its associated complications may relate to total hospital costs. METHODS: The Nationwide Inpatient Sample database was queried from 2008 to 2011. Patients who underwent cervical or lumbar decompression and/or fusion procedures were identified, stratified by approach, and separated into cohorts based on a documented intraoperative incidental durotomy. Patient demographics, comorbidities (Charlson Comorbidity Index), length of hospital stay, perioperative outcomes, and costs were assessed. Analysis of covariance and multivariate linear regression were used to assess the adjusted mean costs of hospitalization as a function of durotomy. RESULTS: The incidental durotomy rate in cervical and lumbar spine surgery is 0.4% and 2.9%, respectively. Patients with an incidental durotomy incurred a longer hospitalization and a greater incidence of perioperative complications including hematoma and neurological injury (P < 0.001). Regression analysis demonstrated that a cervical durotomy and its postoperative sequelae contributed an additional adjusted $7638 (95% confidence interval, 6489-8787; P < 0.001) to the total hospital costs. Similarly, lumbar durotomy contributed an additional adjusted $2412 (95% confidence interval, 1920-2902; P < 0.001) to the total hospital costs. The approach-specific procedural groups demonstrated similar discrepancies in the mean total hospital costs as a function of durotomy. CONCLUSION: This analysis of the Nationwide Inpatient Sample database demonstrates that incidental durotomies increase hospital resource utilization and costs. In addition, it seems that a cervical durotomy and its associated complications carry a greater financial burden than a lumbar durotomy. Further studies are warranted to investigate the long-term financial implications of incidental durotomies in spine surgery and to reduce the costs associated with this complication. LEVEL OF EVIDENCE: 3.

Comparison of revision surgeries for one- to two-level cervical TDR and ACDF from 2002 to 2011.

BACKGROUND CONTEXT: Cervical total disc replacement (TDR) and anterior cervical discectomy and fusion (ACDF) provide comparable outcomes for degenerative cervical pathology. However, revisions of these procedures are not well characterized. PURPOSE: The purpose of this study is to examine the rates, epidemiology, perioperative complications, and costs between the revision procedures and to compare these outcomes with those of primary cases. STUDY DESIGN: This study is a retrospective database analysis. PATIENT SAMPLE: A total of 3,792 revision and 183,430 primary cases from the Nationwide Inpatient Sample (NIS) database from 2002 to 2011 were included. OUTCOME MEASURES: Incidence of revision cases, patient demographics, length of stay (LOS), in-hospital costs, mortality, and perioperative complications. METHODS: Patients who underwent revision for either one- to two-level cervical TDR or ACDF were identified. SPSS v.20 was used for statistical analysis with χ(2) test for categorical data and independent sample t test for continuous data. The relative risk for perioperative complications with revisions was calculated in comparison with primary cases using a 95% confidence interval. An alpha level of less than 0.05 denoted statistical significance. RESULTS: There were 3,536 revision one- to two-level ACDFs and 256 revision cervical TDRs recorded in the NIS database from 2002 to 2011. The revision cervical TDR cohort demonstrated a significantly greater LOS (3.18 vs. 2.25, p<.001), cost ($16,998 vs. $15,222, p=.03), and incidence of perioperative wound infections (13.6 vs. 5.3 per 1,000, p<.001) compared with the ACDF revision cohort (p<.001). There were no differences in mortality between the revision surgical cohorts. Compared with primary cases, both revision cohorts demonstrated a significantly greater LOS and cost. Furthermore, patients who underwent revision demonstrated a greater incidence and risk for perioperative wound infections, hematomas, dysphagia, and neurologic complications relative to the primary procedures. CONCLUSIONS: This study demonstrated a significantly greater incidence of perioperative wound infection, LOS, and costs associated with a TDR revision compared with a revision ACDF. We propose that these differences are by virtue of the inherently more invasive nature of revising TDRs. In addition, compared with primary cases, revision procedures are associated with greater costs, LOS, and complications including wound infections, dysphagia, hematomas, and neurologic events. These additional risks must be considered before opting for a revision procedure.

Complications after lumbar spine surgery between teaching and nonteaching hospitals.

STUDY DESIGN: Retrospective national database analysis. OBJECTIVE: A national population-based database was analyzed to characterize the perioperative complications of lumbar spine procedures performed at teaching and nonteaching hospitals. SUMMARY OF BACKGROUND DATA: Perception biases exist regarding the complications of lumbar spine surgery based upon the hospital teaching environment. METHODS: Data from the Nationwide Inpatient Sample was queried from 2002-2011. Patients undergoing an anterior lumbar interbody fusion, posterior lumbar interbody fusion, anterior/posterior lumbar fusion, or lumbar decompression to treat lumbar degenerative pathology were identified and separated into cohorts based upon the teaching status of the hospital. Patient demographics, Charlson Comorbidity Index, length of stay, complications, mortality, and costs were assessed. RESULTS: A total of 658,616 lumbar procedures were identified from 2002-2011, of which 367,875 (55.9%) were performed at teaching hospitals. An older patient population comprised the teaching hospital cohort and demonstrated a greater comorbidity burden than the nonteaching group (Charlson Comorbidity Index 2.90 vs. 2.55; P < 0.001). In addition, the teaching hospital cohort was associated with a significantly greater number of multilevel fusion cases (P < 0.001) and incurred a greater mean length of stay (3.7 vs. 3.0 d; P < 0.001). Patients treated at teaching hospitals demonstrated a significantly greater incidence of postoperative pulmonary embolism, deep vein thrombosis, infection, and neurological complications than the nonteaching cohort (P < 0.001). Overall, there were no significant differences in the mean total hospital costs or mortality between the hospital cohorts. Regression analysis demonstrated that teaching status was not a significant predictor of mortality (OR, 1.02; confidence interval 0.8-1.2; P = 0.8). CONCLUSION: Patients treated in teaching hospitals for lumbar spine surgery incurred a longer hospitalization and a greater incidence of postoperative complications including pulmonary embolism, deep vein thrombosis, infection, and neurological events. These findings may be explained by an increased complexity of procedures performed at teaching hospitals along with an older and a more comorbid patient population. Despite these differences, the teaching status was not a significant predictor of in-hospital mortality after a lumbar spine surgery. LEVEL OF EVIDENCE: 3.

Body mass index as a predictor of complications and mortality after lumbar spine surgery.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: A national population-based database was analyzed to characterize the risks of postoperative complications and mortality associated with the patient's body mass index (BMI) after lumbar spinal surgery. SUMMARY OF BACKGROUND DATA: Obesity has been associated with greater perioperative complications and worsened surgical outcomes after lumbar spinal surgery. However, the stratified BMI risks of postoperative complications relative to normal weight patients have not been well characterized. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients who underwent lumbar spinal surgery between 2006 and 2011. Patients were stratified into BMI cohorts: normal (18.5-24.99 kg/m), overweight (25.00-29.99 kg/m), class 1 (30.00-34.99 kg/m), class 2 (35.00-39.99 kg/m), and class 3 (≥40 kg/m) obesity. Preoperative patient characteristics and perioperative outcomes were assessed. The relative risks of 30-day postoperative complications and mortality for each BMI cohort were calculated in reference to the normal weight cohort using a 95% confidence interval. RESULTS: A total of 24,196 patients underwent lumbar spine surgery between 2006 and 2011 of which 19,195 (79.3%) were overweight or obese. The risk for deep vein thrombosis increased beginning with overweight patients and compounded for the subsequent obesity classes. The risk for superficial wound infection and pulmonary embolism increased beginning with the class 1 obesity cohort. Furthermore, the relative risk increase for urinary tract infection, acute renal failure, and sepsis was significantly increased only among class 3 obesity patients. Lastly, there was no relative risk increase in 30-day mortality in any cohort after lumbar spine surgery. CONCLUSION: Overweight and obese patients demonstrated an increased risk of postoperative complications relative to normal weight patients. Despite these findings, a BMI 25 kg/m or more was not associated with a greater risk of mortality. Further studies are warranted to characterize the impact of postoperative complications associated with overweight and obese patients on hospital resource utilization and costs after lumbar spine surgery.

Sentinel Events in Lumbar Spine Surgery.

STUDY DESIGN: Retrospective national database analysis. OBJECTIVE: A national population-based database was queried to investigate the incidence and perioperative outcomes associated with sentinel events in lumbar spine surgery. SUMMARY OF BACKGROUND DATA: Sentinel events in lumbar spine surgery can have significant medical, social, economic, and legal implications. The incidence and perioperative outcomes associated with these events have not been well characterized. METHODS: Data from the Nationwide Inpatient Sample was queried from 2002 to 2011. Patients who underwent lumbar spinal surgery were identified. Sentinel events including bowel or peritoneal injury, vascular injury, nerve injury, retention of foreign objects, and wrong-site surgery were identified. Patient demographics, comorbidities (Charlson Comorbidity Index), length of stay, total costs, and perioperative outcomes were assessed. The risk for mortality associated with each sentinel event was calculated using a 95% confidence interval. Statistical analysis was performed with SPSS version 20 and a P value of 0.001 or less denoted significance. RESULTS: A total of 543,146 lumbar spine surgical procedures were recorded from 2002 to 2011, of which 414 (0.8 per 1000 cases) incurred sentinel events. Wrong-site surgical procedures were the most common sentinel events with an incidence of 0.3 per 1000 cases. The incidences for bowel or peritoneal injury, vascular injury, nerve injury, and retention of foreign objects, were 0.06, 0.2, 0.2, and 0.1 per 1000 cases, respectively. There were no significant differences in the mean age (55.9 vs. 56.0, P = 0.911) or comorbidity burden (2.58 vs. 2.63, P = 0.553) between the 2 cohorts. The sentinel event cohort incurred a longer hospitalization, greater costs, and a greater incidence of in-hospital complications, and mortality. Patients with a bowel or peritoneal injury, vascular injury, and wrong-site surgery demonstrated a greater risk of mortality relative to unaffected patients. CONCLUSION: This Nationwide Inpatient Sample analysis demonstrates that sentinel events are associated with a significant increase in hospital resource utilization and worsened postoperative outcomes including death. This study demonstrates the financial and medical burden associated with sentinel events in lumbar spine surgery. LEVEL OF EVIDENCE: 4.

Sentinel events in cervical spine surgery.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: A national population-based database was queried to investigate the incidence of sentinel events in cervical spine surgery as well as the associated perioperative outcomes. SUMMARY OF BACKGROUND DATA: Sentinel events in cervical spine surgery are potentially catastrophic complications. The incidence and perioperative outcomes associated with sentinel events in cervical spine surgery have not been well characterized. METHODS: The Nationwide Inpatient Sample was queried from 2002 to 2011. Patients who underwent elective cervical spinal surgery were identified. Sentinel events including esophageal perforation, vascular injury, nerve injury, retention of foreign objects, and wrong-site surgery were identified. Patient demographics, comorbidities (Charlson Comorbidity Index), surgical procedures, length of stay, total hospital costs, and postoperative outcomes were assessed. The risk for in-hospital mortality associated with each complication was calculated using a 95% confidence interval (CI). Statistical analysis was performed with SPSS version 20, and a P ≤ 0.001 denoted significance. RESULTS: A total of 251,318 cervical spine procedures were identified between 2002 and 2011, of which 123 patients (0.5 per 1000 cases) incurred sentinel events. Circumferential cervical fusion (anterior-posterior cervical fusion) demonstrated an increased risk of vascular injury (odds ratio [OR], 4.5; CI, 1.8-11.2), whereas cervical total disc replacement was associated with an increased risk of esophageal perforation (OR, 10.9; CI, 1.4-85.2) and nerve injury (OR, 36.4; CI, 1.5-892.3). Posterior cervical fusions were associated with an increased risk of wrong-site surgery (OR, 3.9; CI, 1.5-10.5). The sentinel event cohort incurred longer hospitalization, greater costs, mortality, and greater incidence of postoperative complications. CONCLUSION: This database analysis demonstrates that sentinel events are associated with a significant increase in hospital resource utilization and worsened perioperative outcomes. The type of cervical spine procedure and the number of fusion levels significantly impact the risk of sentinel events. Further research is warranted to understand the etiology of sentinel events in cervical spine surgery and to implement protocols to mitigate the associated risk factors. LEVEL OF EVIDENCE: 4.

Incidence, risk factors, and outcomes of postoperative airway management after cervical spine surgery.

STUDY DESIGN: Retrospective database analysis. OBJECTIVE: To identify the incidence and risk factors for a prolonged intubation or an unplanned reintubation after cervical spine surgery (CSS). SUMMARY OF BACKGROUND DATA: Patients who undergo CSS occasionally require prolonged mechanical ventilation or an unplanned reintubation for airway support. Despite the potential severity of these complications, there are limited data in the published literature addressing this issue. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients who underwent a CSS. Patients who required a prolonged intubation more than 48 hours or an unplanned reintubation after CSS were compared with those without airway compromise. Preoperative patient characteristics, intraoperative variables, hospital length of stay, 30-day complication rates, and mortality were compared between the cohorts. An α ≤ 0.001 denoted statistical significance. A multivariate regression model was used to identify independent predictors for a prolonged intubation and an unplanned reintubation. RESULTS: A total of 8648 cervical spine procedures were identified from 2006 to 2011 of which 54 patients (0.62%) required prolonged ventilation and 56 patients (0.64%) underwent a postoperative reintubation. Patients who required postoperative airway management were older and demonstrated a greater comorbidity burden (P < 0.001). In addition, the affected cohorts demonstrated a significantly greater rate of readmissions, reoperations, postoperative complications, and mortality (P < 0.001). Regression analysis identified the independent predictors for prolonged ventilation to include a history of cardiac disease and dialysis along with a low preoperative albumin level (P < 0.05). Similarly, the independent risk factors for a postoperative reintubation included a history of recent weight loss more than 10%, recent operation within 30 days, low preoperative hematocrit, and a high serum creatinine (P < 0.05). CONCLUSION: Postoperative airway management is a rare complication after CSS. A prolonged intubation and an unplanned reintubation carry a greater rate of postoperative complications and mortality. High-risk patients should be identified prior to surgery to mitigate the risk factors for postoperative airway compromise. LEVEL OF EVIDENCE: 3.

Cerebral vascular accidents after lumbar spine fusion.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To determine the impact of a cerebral vascular accident (CVA) after lumbar spinal fusion, a population-based database was analyzed to identify the incidence, potential risk factors, hospital resource utilization, and the early postoperative outcomes. SUMMARY OF BACKGROUND DATA: A lumbar fusion (LF) is an effective surgical procedure to treat lumbar degenerative pathology. Although rare, a CVA can be a catastrophic event after an LF. METHODS: The Nationwide Inpatient Sample database was queried from 2002-2011. Patients undergoing an elective anterior lumbar fusion, a posterior lumbar fusion, or a combined anterior-posterior lumbar fusion were separated into subcohorts. Patients with a documented postoperative CVA were identified. Patient demographics, comorbidities (Charlson Comorbidity Index), length of stay, costs, early postoperative outcomes, and mortality were assessed. Statistical analysis involved T tests, χ2 analysis, and binary logistic regression with P < 0.001 denoting significance. RESULTS: A total of 264,891 LFs were identified between 2002 and 2011 of which 340 (1.3 per 1000) developed a postoperative CVA. Patients with a CVA were significantly older and demonstrated a greater comorbidity burden (Charlson Comorbidity Index). Patients with a CVA incurred a significantly greater length of stay, total hospital costs ($41,454 vs. $25,885), and a greater mortality rate (73.7 vs. 0.8 per 1000 patients). Regression analysis demonstrated that age more than 65 years and a history of neurological disorders, paralysis, congestive heart failure, or electrolyte imbalance were associated with an increased risk of a postoperative CVA. CONCLUSION: Patients who developed a postoperative CVA demonstrated a significantly greater incidence of postoperative complications, mortality, and total hospital costs. This study highlights important associated risk factors (e.g., age more than 65, neurological disorders, congestive heart failure) that may enable surgeons to identify high-risk patients prior to surgery. Further studies are warranted to characterize these risk factors and to establish guidelines to mitigate the complications associated with a postoperative CVA. LEVEL OF EVIDENCE: 4.

Perioperative characteristics and outcomes of patients undergoing anterior cervical fusion in July: analysis of the "July effect".

STUDY DESIGN: Retrospective national database analysis. OBJECTIVE: A national population-based database was analyzed to characterize the "July effect" on the perioperative outcomes of anterior cervical fusions (ACFs). SUMMARY OF BACKGROUND DATA: Perception biases exist regarding the outcomes of cervical spine surgery based upon the month of admission. METHODS: The Nationwide Inpatient Sample database was queried from 2009-2011. Patients who underwent an ACF in teaching and nonteaching hospitals were identified and separated into cohorts. Patients who were admitted in July were then compared with non-July admissions in both cohorts. Demographics, Charlson Comorbidity Index, length of stay, costs, postoperative complications, and mortality were assessed. RESULTS: A total of 52,499 ACF cases were identified in the Nationwide Inpatient Sample of which 26,831 (51.2%) were performed in teaching hospitals and 25,668 (48.8) in nonteaching institutions. July admissions represented 6.8% and 7.4% of cases in the teaching and nonteaching hospital cohorts, respectively. Among July admissions, the teaching cohort incurred a longer hospitalization than the nonteaching cohort (P < 0.05). In contrast, no significant differences in mortality or total hospital costs were demonstrated. In teaching institutions, the in-hospital complications associated with July patients included deep vein thrombosis and surgical site infection (P < 0.05), but this did not reach significance in nonteaching hospitals. Postoperative dysphagia and deep vein thromboses were also significantly more prevalent among July admissions in teaching hospitals compared with nonteaching institutions. CONCLUSION: This national study demonstrated that the early resident academic year was associated with a greater length of stay among July patients in teaching hospitals. This study did not demonstrate an increase in mortality or total hospital costs among July patients in either hospital cohort. In teaching hospitals, ACF-treated patients in July were associated with a greater incidence of postoperative thromboses and surgical site infection. In addition, the incidence of dysphagia was significantly greater among July patients in teaching hospitals than nonteaching hospitals.

A perioperative cost analysis comparing single-level minimally invasive and open transforaminal lumbar interbody fusion.

BACKGROUND CONTEXT: Emerging literature suggests superior clinical short- and long-term outcomes of MIS (minimally invasive surgery) TLIFs (transforaminal lumbar interbody fusion) versus open fusions. Few studies to date have analyzed the cost differences between the two techniques and their relationship to acute clinical outcomes. PURPOSE: The purpose of the study was to determine the differences in hospitalization costs and payments for patients treated with primary single-level MIS versus open TLIF. The impact of clinical outcomes and their contribution to financial differences was explored as well. STUDY DESIGN/SETTING: This study was a nonrandomized, nonblinded prospective review. PATIENT SAMPLE: Sixty-six consecutive patients undergoing a single-level TLIF (open/MIS) were analyzed (33 open, 33 MIS). Patients in either cohort (MIS/open) were matched based on race, sex, age, smoking status, medical comorbidities (Charlson Comorbidity index), payer, and diagnosis. Every patient in the study had a diagnosis of either degenerative disc disease or spondylolisthesis and stenosis. OUTCOME MEASURES: Operative time (minutes), length of stay (LOS, days), estimated blood loss (EBL, mL), anesthesia time (minutes), Visual Analog Scale (VAS) scores, and hospital cost/payment amount were assessed. METHODS: The MIS and open TLIF groups were compared based on clinical outcomes measures and hospital cost/payment data using SPSS version 20.0 for statistical analysis. The two groups were compared using bivariate chi-squared analysis. Mann-Whitney tests were used for non-normal distributed data. Effect size estimate was calculated with the Cohen d statistic and the r statistic with a 95% confidence interval. RESULTS: Average surgical time was shorter for the MIS than the open TLIF group (115.8 minutes vs. 186.0 minutes respectively; p=.001). Length of stay was also reduced for the MIS versus the open group (2.3 days vs. 2.9 days, respectively; p=.018). Average anesthesia time and EBL were also lower in the MIS group (p<.001). VAS scores decreased for both groups, although these scores were significantly lower for the MIS group (p<.001). Financial analysis demonstrated lower total hospital direct costs (blood, imaging, implant, laboratory, pharmacy, physical therapy/occupational therapy/speech, room and board) in the MIS versus the open group ($19,512 vs. $23,550, p<.001). Implant costs were similar (p=.686) in both groups, although these accounted for about two-thirds of the hospital direct costs in the MIS cohort ($13,764) and half of these costs ($13,778) in the open group. Hospital payments were $6,248 higher for open TLIF patients compared with the MIS group (p=.267). CONCLUSIONS: MIS TLIF technique demonstrated significant reductions of operative time, LOS, anesthesia time, VAS scores, and EBL compared with the open technique. This reduction in perioperative parameters translated into lower total hospital costs over a 60-day perioperative period. Although hospital reimbursements appear higher in the open group over the MIS group, shorter surgical times and LOS days in the MIS technique provide opportunities for hospitals to reduce utilization of resources and to increase surgical case volume.

Prospective, randomized, controlled trial of silicate-substituted calcium phosphate versus rhBMP-2 in a minimally invasive transforaminal lumbar interbody fusion.

STUDY DESIGN: Prospective, randomized, controlled trial. OBJECTIVE: To compare arthrodesis rates between patients undergoing a primary single-level minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) with either Actifuse or recombinant human bone morphogenetic protein-2 (rhBMP-2). SUMMARY OF BACKGROUND DATA: Preclinical animal studies suggest that silicate-substituted calcium phosphate (Actifuse) bone graft substitute offers equivalent or an increased fusion rate compared with other graft enhancers/extenders and rhBMP-2. METHODS: Fifty-two patients undergoing a single-level unilateral MIS TLIF were evenly randomized into 2 cohorts as follows: the Actifuse cohort received Actifuse combined with 5 mL of bone marrow aspirate (n = 26; 50%), whereas the rhBMP cohort received 4.2 mg of rhBMP-2 (n = 26; 50%). A pre hoc G*Power analysis yielded a sample size of n = 26 that was determined through a 2-tailed distribution calculation. Computed tomographic analysis was performed at 6 months and 1 year postoperatively. Pre- and postoperative visual analogue scale scores were obtained to assess the clinical outcomes. Arthrodesis was determined by 2 separate, blinded orthopedic surgeons and a board certified radiologist. RESULTS: At 1-year follow-up, 65% (17/26) of the Actifuse cohort and 92% (24/26) of the rhBMP-2 cohort demonstrated a radiographical arthrodesis (P = 0.01). In both study cohorts, the 1-year postoperative visual analogue scale scores significantly improved (P < 0.001). Pseudarthrosis rates at 1 year were 35.0% (9/26) and 7.7% (2/26) for the Actifuse and rhBMP-2 groups, respectively (P = 0.01, OR = 6.35, 95% CI = 1.22-33.1). A greater reoperation rate was noted in the Actifuse cohort (35.0%, 9/26) compared with the BMP-2 cohort (7.7%, 2/26; P = 0.01). One patient with BMP-2 also experienced symptomatic neuroforaminal bone growth (3.8%, n = 1/26). CONCLUSION: Silicate-substituted calcium phosphate was associated with a significantly lower rate of arthrodesis than rhBMP-2 in a MIS TLIF. The patients with pseudarthrosis in both cohorts were all clinically symptomatic with an unimproved visual analogue scale score. Additional analysis of Actifuse and other graft enhancers/extenders are needed prior to the utilization for an MIS TLIF. LEVEL OF EVIDENCE: 2.