Complications and intercenter variability of three-column resection osteotomies for spinal deformity surgery: a retrospective review of 423 patients

Prophylactic cryoprecipitate transfusion in patients undergoing scoliosis surgery: A randomised-controlled trial

BACKGROUND

Scoliosis surgeries in adults often have a high risk of massive blood loss and significant transfusion of blood products during and after surgery. It is not known whether early cryoprecipitate therapy is useful in reducing blood loss and transfusion requirements. The objective of this randomised, prospective placebo control study was to evaluate whether prophylactic administration of cryoprecipitate would reduce blood loss and transfusion requirements during scoliosis surgery.

METHODS

Eighty adult patients scheduled to undergo elective scoliosis correction were randomly assigned to receive either ten units of cryoprecipitate before incision (cryo group) or an equivalent volume of 0.9% saline (placebo group). Blood loss, transfusion requirements, coagulation parameters and complications were assessed.

RESULTS

No significant differences were found in the volume of transfused blood products, intraoperative estimated blood loss between the intervention and placebo groups. Postoperative blood loss was significantly lower in the cry group when compared to the other group. During adult surgical correction of scoliosis, prophylactic administration of cryoprecipitate did not diminish the amount of transfused blood products or decrease intraoperative blood loss.

CONCLUSION

It could be concluded that the prophylactic administration of cryoprecipitate shows no differences in intraoperative blood loss and transfusion requirements during scoliosis surgery.

Postoperative dysesthesia after PVCR without anterior support applied in Yang's type A severe spinal kyphoscoliosis

Backgrounds

The incidence and characteristics of postoperative dysesthesia (POD) have not been reported for posterior vertebral column resection (PVCR) in the treatment of severe spinal kyphoscoliosis.

Objective

The objective of the study is to investigate the incidence and characteristics of POD in PVCR without anterior support applied in Yang's type A severe spinal kyphoscoliosis.

Material and methods

From August 2010 to December 2019, 167 patients diagnosed with Yang's type A severe spinal kyphoscoliosis who underwent PVCR without anterior support applied were retrospectively reviewed. All the patients were monitored using five modes of intraoperative multimodal neurophysiological monitoring. Neuromonitoring data, radiographic parameters, and neurological complications were reviewed and analyzed. The incidence and characteristics of POD were further summarized. POD was defined as dysesthetic pain or burning dysesthesia which could be caused by spinal cord kinking or dorsal root ganglion (DRG) injury but with no motor deficits.

Results

PVCR without anterior support was successfully conducted in all 167 patients. Intraoperative monitoring events occurred in five patients. One out of these five patients showed postoperative spinal cord injury (Frankel level C) but completely recovered within 9 months postoperation (Frankel level E). The number of levels and osteotomy space for vertebra resection were 1.28 and 3.6 cm, respectively. POD was confirmed in three patients (3/167, 1.8%), characterized as kyphosis with the apex vertebrae in T12 with the kyphotic Cobb angles of 100°, 115°, and 122°, respectively. The osteotomy space of vertebra resection in these three patients were 3.9, 3.8, and 4.2 cm, respectively. After the treatment by drug administration, they reported pain relief for 12-36 days. The pain gradually moved to the distal end of a proper DRG innervated region near the end.

Conclusions

In this study, the incidence rate of POD in Yang's type A severe spinal kyphoscoliosis patients who underwent PVCR without anterior support applied was 1.8% (3/167). Evoked potential monitoring could not detect the occurrence of POD. POD in Yang's type A severe spinal kyphoscoliosis after PVCR could be ascribed to spinal cord kinking and DRG injury.

Comparative Analysis of Early Outcomes and Complications of PSO Among Neurosurgeons and Orthopedic Surgeons

STUDY DESIGN

Retrospective comparative cohort study using the National Surgical Quality Improvement Program.

OBJECTIVE

The aim of this study was to evaluate trends in the annual number of PSOs performed, describe the patient populations associated with each cohort, and compare outcomes between specialties.Summary of Background Data:Pedicle subtraction osteotomies (PSO) are complex and advanced spine deformity surgical procedures performed by neurosurgeons and orthopedic surgeons. Though both sets of surgeons can be equally qualified and credentialed to perform a PSO, it is possible that differences in training and exposure could translate into differences in patient management and outcomes.

METHODS

Patients that underwent lumbar PSO from 2005 to 2014 in the American College of Surgeons-National Surgical Quality Improvement Program registry were identified. Relevant demographic, preoperative comorbidity, and postoperative 30-day complications were queried and analyzed. The data was divided into 2 cohorts consisting of those patients who were treated by neurosurgeons versus orthopedic surgeons. Additional data from the Scoliosis Research Society Morbidity and Mortality database was queried and analyzed for comparison.

RESULTS

Demographic and comorbidity factors were similar between the neurosurgery and orthopedic surgery cohorts, except there were higher rates of hypertension among orthopedic surgeon-performed PSOs (65.66% vs. 48.67%, P =0.004). Except for 2012, in every year queried, orthopedic surgeons reported more PSOs than neurosurgeons. In patients who underwent lumbar fusion surgery, there was a higher rate of PSOs if the surgery was performed by an orthopedic surgeon (OR 1.7824, 95% CI: 1.4017-2.2665). The incidence of deep vein thrombosis after PSOs was higher for neurosurgery compared with orthopedic surgery (8.85% vs. 1.20%, P =0.004). However, besides deep vein thrombosis, there were no salient differences in surgical complication rates between neurosurgeon-performed PSOs and orthopedic surgeon-performed PSOs.

CONCLUSIONS

The number of PSO procedures performed by neurosurgeons and orthopedic surgeons has increased annually. Differences in outcomes between neurosurgeons and orthopedic surgeons suggest an opportunity for wider assessment and alignment of adult spinal deformity surgery exposure and training across specialties.

Surgical bleeding in patients undergoing posterior lumbar inter-body fusion surgery: a randomized clinical trial evaluating the effect of two mechanical ventilation mode types

BACKGROUND

The purpose of the study was to compare the effect of using volume-controlled ventilation (VCV) versus pressure-controlled ventilation (PCV) on blood loss in patients undergoing posterior lumbar inter-body fusion (PLIF) surgery.

METHODS

In a randomized, single-blinded, parallel design, 78 patients, candidates for PLIF surgery, were randomly allocated into two groups of 39 to be mechanically ventilated using VCV or PCV mode. All the patients were operated in prone position by one surgeon. Amount of intraoperative surgical bleeding, transfusion requirement, surgeon satisfaction, hemodynamic parameters, heart rate, and blood pressure were measured as outcomes.

RESULTS

PCV group showed slightly better outcomes than VCV group in terms of mean blood loss (431 cc vs. 465 cc), transfusion requirement (0.40 vs. 0.43 unit), and surgeon satisfaction (82.1% vs. 74.4%); however, the differences were not statistically significant. Diastolic blood pressure 90 and 105 min after induction were significantly lower in PCV group (P = 0.043-0.019, respectively); however, blood pressure at other times, hemoglobin levels, and mean heart rate were similar in two groups.

CONCLUSIONS

In patients undergoing posterior lumbar inter-body fusion surgery, mode of ventilation cannot make significant difference in terms of blood loss; however, some minor benefits in outcomes may lead to the selection of PCV rather than VCV. More studies with larger sample size, and investigating more factors may be needed.

30-day postoperative sepsis risk factors following laminectomy for intradural extramedullary tumors

BACKGROUND

Posterior laminectomy (LA) for resection of intradural extramedullary tumors (IDEMTs) is associated with postoperative complications, including sepsis. Sepsis is an uncommon but serious complication that can lead to increased morbidity and mortality, prolonged hospital stays, and greater costs. Given the susceptibility of a solid tumor patients to sepsis-related complications, it is important to recognize IDEMT patients as a unique population when assessing the risk factors for sepsis after laminectomy.

METHODS

The study design was a retrospective cohort study. Adult patients undergoing LA for IDEMTs from 2012 to 2018 were identified in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database. Baseline patient characteristics/comorbidities, operative and hospital variables, and 30-day postoperative complications were collected.

RESULTS

Of 2,027 total patients undergoing LA for IDEMTs, 38 (2%) had postoperative sepsis. On bivariate analysis sepsis was associated with superficial surgical site infection [odds ratio (OR) 11.62, P<0.001], deep surgical site infection (OR 10.67, P<0.001), deep vein thrombosis (OR 10.75, P<0.001), pulmonary embolism (OR 15.27, P<0.001), transfusion (OR 6.18, P<0.001), length of stay greater than five days (OR 5.41, P<0.001), and return to the operating room within thirty days (OR 8.72, P<0.001). Subsequent multivariate analysis identified the following independent risk factors for sepsis and septic shock: operative time ≥50th percentile (OR 2.11, P=0.032), higher anesthesia class (OR 1.76, P=0.046), dependent functional status (OR 2.23, P=0.001), diabetes (OR 2.31, P=0.037), and chronic obstructive pulmonary disease (OR 3.56, P=0.037).

CONCLUSIONS

These findings can help spine surgeons identify high-risk patients and proactively deploy measures to avoid this potentially devastating complication in individuals who may be more vulnerable than the general elective spine population.

Enhanced Safety of Pedicle Subtraction Osteotomy Using Intraoperative Ultrasound

BACKGROUND

Pedicle subtraction osteotomy (PSO) can improve sagittal alignment but carries risks, including iatrogenic spinal cord and nerve root injury. Critically, during the reduction phase of the technique, medullary kinking or neural element compression can lead to neurologic deficits.

METHODS

We describe 3 cases of thoracic PSO and evaluate the feasibility, findings, and utility of intraoperative ultrasound in this setting.

RESULTS

Intraoperative ultrasound can provide a visual assessment of spinal cord morphology before and after PSO reduction and influences surgical decision making with regard to the final amount of sagittal plane correction. This modality is particularly useful for confirming ventral decompression of disc-osteophyte complex before reduction and also after reduction maneuvers when there is kinking of the thecal sac but uncertainty about the underlying status of the spinal cord. Intraoperative ultrasound is a reliable modality that fits well into the technical sequence of PSO, adds a minimal amount of operative time, and has few limitations.

CONCLUSIONS

We propose that intraoperative ultrasound is a useful supplement to standard neuromonitoring modalities for ensuring safe PSO reduction and decompression of neural elements.

Postoperative Low-Dose Tranexamic Acid After Major Spine Surgery: A Matched Cohort Analysis

OBJECTIVE

This was a retrospective, cohort study investigating the efficacy and safety of continuous low-dose postoperative tranexamic acid (PTXA) on drain output and transfusion requirements following adult spinal deformity surgery.

METHODS

One hundred forty-seven patients undergoing posterior instrumented thoracolumbar fusion of ≥ 3 vertebral levels at a single institution who received low-dose PTXA infusion (0.5-1 mg/kg/hr) for 24 hours were compared to 292 control patients who did not receive PTXA. The cohorts were propensity matched based on age, sex, American Society of Anesthesiologist physical status classification, body mass index, number of surgical levels, revision surgery, operative duration, and total intraoperative TXA dose (n = 106 in each group). Primary outcome was 72-hour postoperative drain output. Secondary outcomes were number of allogeneic blood transfusions.

RESULTS

There was no significant difference in postoperative drain output in the PTXA group compared to control (660 ± 420 mL vs. 710 ± 490 mL, p = 0.46). The PTXA group received significantly more crystalloid (6,100 ± 3,100 mL vs. 4,600 ± 2,400 mL, p < 0.001) and red blood cell transfusions postoperatively (median [interquartile range]: 1 [0-2] units vs. 0 [0-1] units; incidence rate ratio [95% confidence interval], 1.6 [1.2-2.2]; p = 0.001). Rates of adverse events were comparable between groups.

CONCLUSION

Continuous low-dose PTXA infusion was not associated with reduced drain output after spinal deformity surgery. No difference in thromboembolic incidence was observed. A prospective dose escalation study is warranted to investigate the efficacy of higher dose PTXA.

Rotational thromboelastometry-guided transfusion during lumbar pedicle subtraction osteotomy for adult spinal deformity: preliminary findings from a matched cohort study

OBJECTIVESignificant blood loss and coagulopathy are often encountered during adult spinal deformity (ASD) surgery, and the optimal intraoperative transfusion algorithm is debatable. Rotational thromboelastometry (ROTEM), a functional viscoelastometric method for real-time hemostasis testing, may allow early identification of coagulopathy and improve transfusion practices. The objective of this study was to investigate the effect of ROTEM-guided blood product management on perioperative blood loss and transfusion requirements in ASD patients undergoing correction with pedicle subtraction osteotomy (PSO).METHODSThe authors retrospectively reviewed patients with ASD who underwent single-level lumbar PSO at the University of Virginia Health System. All patients who received ROTEM-guided blood product transfusion between 2015 and 2017 were matched in a 1:1 ratio to a historical cohort treated using conventional laboratory testing (control group). Co-primary outcomes were intraoperative estimated blood loss (EBL) and total blood product transfusion volume. Secondary outcomes were perioperative transfusion requirements and postoperative subfascial drain output.RESULTSThe matched groups (ROTEM and control) comprised 17 patients each. Comparison of matched group baseline characteristics demonstrated differences in female sex and total intraoperative dose of intravenous tranexamic acid (TXA). Although EBL was comparable between ROTEM versus control (3200.00 ± 2106.24 ml vs 3874.12 ± 2224.22 ml, p = 0.36), there was a small to medium effect size (Cohen's d = 0.31) on EBL reduction with ROTEM. The ROTEM group had less total blood product transfusion volume (1624.18 ± 1774.79 ml vs 2810.88 ± 1847.46 ml, p = 0.02), and the effect size was medium to large (Cohen's d = 0.66). This difference was no longer significant after adjusting for TXA (β = -0.18, 95% confidence interval [CI] -1995.78 to 671.64, p = 0.32). More cryoprecipitate and less fresh frozen plasma (FFP) were transfused in the ROTEM group patients (cryoprecipitate units: 1.24 ± 1.20 vs 0.53 ± 1.01, p = 0.03; FFP volume: 119.76 ± 230.82 ml vs 673.06 ± 627.08 ml, p < 0.01), and this remained significant after adjusting for TXA (cryoprecipitate units: β = 0.39, 95% CI 0.05 to 1.73, p = 0.04; FFP volume: β = -0.41, 95% CI -772.55 to -76.30, p = 0.02). Drain output was lower in the ROTEM group and remained significant after adjusting for TXA.CONCLUSIONSFor ASD patients treated using lumbar PSO, more cryoprecipitate and less FFP were transfused in the ROTEM group compared to the control group. These preliminary findings suggest ROTEM-guided therapy may allow early identification of hypofibrinogenemia, and aggressive management of this may reduce blood loss and total blood product transfusion volume. Additional prospective studies of larger cohorts are warranted to identify the appropriate subset of ASD patients who may benefit from intraoperative ROTEM analysis.

Surgical Treatment of Flat Back Syndrome With Anterior Hyperlordotic Cages

BACKGROUND

Traditional correction for flat back syndrome is performed with a posterior-based surgery or combined approaches in revision cases.

OBJECTIVE

To evaluate outcome from anterior surgery with the use of hyperlordotic cages (HLCs) in patients with flat back syndrome.

METHODS

All patients operated with or without prior posterior lumbar surgery were studied. Pre- to postoperative sagittal alignment was analyzed. Radiographic parameters were analyzed including T1 pelvic angle (T1PA), sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), lumbar lordosis (LL), sacral slope (SS), pelvic incidence and lumbar lordosis (PI-LL), and T4-12TK.

RESULTS

All 50 patients (mean age of 58 yr, 72% female with mean body mass index of 28) demonstrated significant radiographic alignment difference in their spinopelvic and global parameters from pre- to postoperative standing: LL (-37.04° vs -59.55°, P < .001), SS (35.12 vs 41.13, P < .001), PI-LL (23.55 vs 6.46), T4-12 TK (30.59 vs 41.67), PT (28.22 vs 22.13), SVA in mm (80.94 vs 37.39), and T1PA (28.70° vs 18.43°, P < .001). Using linear regression analysis, predicted pre- to postoperative change in standing LL corresponded to a pre- to postoperative changes in standing PI-LL mismatch, T1PA, TK, SS, PT, and SVA (R2 = 0.59, 0.38, 0.25, 0.16, 0.12, and 0.17, respectively). Five degrees of pre- to postoperative change in T1PA translates to -4.15° change in LL.

CONCLUSION

Anterior surgery with HLCs followed by posterior instrumentation is an effective technique to treat flat back syndrome. HLCs are effective to maximize LL up to 30°, which is equivalent in magnitude to a pedicle subtraction osteotomy, but associated with less blood loss, quicker recovery, lower complications, and good surgical outcome.

Multilevel Arthrodesis for Adult Spinal Deformity: When Should We Anticipate Major Blood Loss?

STUDY DESIGN

Retrospective study.

OBJECTIVES

To analyze predictors of major blood loss (MBL) during multilevel arthrodesis for adult spinal deformity (ASD).

SUMMARY OF BACKGROUND DATA

ASD surgery is associated with substantial blood loss.

METHODS

We identified 237 patients with ASD who underwent spinal arthrodesis of five or more levels by one surgeon and who had complete data on blood loss. MBL was defined as normalized blood loss above the 75th percentile (ie, >49%). Patients with MBL were compared with those without MBL with respect to baseline characteristics, preoperative laboratory values, and surgical factors. Alpha level = 0.05.

RESULTS

A total of 176 patients (74%) had MBL. On univariate analysis, the MBL and non-MBL groups differed with respect to diagnosis of osteoporosis (p = .002), curve type (p = .012), number of levels fused (p < .001), and presence/type of osteotomy (p < .001). The groups were similar in age (p = .605) and proportion of patients undergoing revision surgery (p = .410). Multivariate analysis identified the following predictors of MBL: three-column osteotomy (odds ratio [OR] = 4.1, 95% confidence interval [CI] = 1.7, 9.7), arthrodesis of 11 or more levels (OR = 3.2, 95% CI = 1.4, 7.6), malalignment in both coronal and sagittal planes (OR = 3.2, 95% CI = 1.4, 7.3), and osteoporosis (OR = 2.4, 95% CI = 1.1, 5.4).

CONCLUSION

Patients with ASD undergoing spinal arthrodesis of five or more levels are at risk for MBL. Three-column osteotomy, arthrodesis of ≥11 levels, malalignment in both coronal and sagittal planes, and osteoporosis appear to be risk factors for MBL.

LEVEL OF EVIDENCE

Level III.

Safety of a High-Dose Tranexamic Acid Protocol in Complex Adult Spinal Deformity: Analysis of 100 Consecutive Cases

STUDY DESIGN

Retrospective review of high-dose tranexamic acid (TXA) use in consecutive patients.

OBJECTIVE

To determine the safety profile of a high-dose TXA protocol in complex adult spinal deformity patients.

SUMMARY OF BACKGROUND DATA

Adult spinal deformity (ASD) surgery may involve significant amounts of blood loss, especially when various osteotomy techniques are used. Antifibrinolytic agents such as TXA have been used to reduce intraoperative blood loss. However, there is no universally accepted dosing protocol for its use during complex ASD surgery.

METHODS

Consecutive patients undergoing spinal deformity correction over a 14-month period at a single institution were identified. Inclusion criteria were adults (age ≥18 years) who underwent posterior spinal fusion of at least 5 levels and use of our standard TXA protocol of 50 mg/kg intravenous loading dose followed by a 5-mg/kg/h infusion until skin closure. Patient demographics, estimated blood loss (EBL), operative time, transfusion rates, complications, and other procedure-specific information were recorded.

RESULTS

A total of 100 adult patients were included. All operative procedures were performed by the senior surgeon. The mean age was 47.3 years, and 71% of patients were female. Average body mass index was 24.9. The average fusion length was 14 levels; 33/100 patients had fusion constructs of 17 levels or more. Pedicle subtraction osteotomy was performed in 9 patients and vertebral column resections were performed in 14 patients. There were 45/100 patients who had a primary procedure, whereas the rest were revisions. Mean EBL was 1,336 mL (98 mL/level, 31% estimated blood volume). There were three thromboembolic complications, including one pulmonary embolism and two deep vein thromboses (DVTs), which were all treated successfully with anticoagulation. There were no cases of myocardial infarction, seizure, stroke, or acute renal failure.

CONCLUSIONS

This is the first study to demonstrate the use of high-dose TXA in a complex ASD population. Larger prospective studies are needed to assess the efficacy and safety of high-dose TXA in ASD.

LEVEL OF EVIDENCE

Level IV, therapeutic.

Adult Degenerative Lumbar Scoliosis

Adult degenerative lumbar scoliosis is a 3-dimensional deformity defined as a coronal deviation of greater than 10°. It causes significant pain and disability in the elderly. With the aging of the population, the incidence of adult degenerative lumbar scoliosis will continue to increase. During the past decade, advancements in surgical techniques and instrumentation have changed the management of adult spinal deformity and led to improved long-term outcomes. In this article, the authors provide a comprehensive review of the pathophysiology, diagnosis, and management of adult degenerative lumbar scoliosis. [Orthopedics. 2017; 40(6):e930-e939.].

Neurosurgical applications of viscoelastic hemostatic assays

Patients taking antithrombotic agents are very common in neurosurgical practice. The perioperative management of these patients can be extremely challenging especially as newer agents, with poorly defined laboratory monitoring and reversal strategies, become more prevalent. This is especially true with emergent cases in which rapid reversal of anticoagulation is required and the patient’s exact medical history is not available. With an aging patient population and the associated increase in diseases such as atrial fibrillation, it is expected that the use of these agents will continue to rise in coming years. Furthermore, thromboembolic complications such as deep venous thrombosis, pulmonary embolism, and myocardial infarction are common complications of major surgery. These trends, in conjunction with a growing understanding of the hemostatic process and its contribution to the pathophysiology of disease, stress the importance of the complete evaluation of a patient’s hemostatic profile in guiding management decisions. Viscoelastic hemostatic assays (VHAs), such as thromboelastography and rotational thromboelastometry, are global assessments of coagulation that account for the cellular and plasma components of coagulation. This FDA-approved technology has been available for decades and has been widely used in cardiac surgery and liver transplantation. Although VHAs were cumbersome in the past, advances in software and design have made them more accurate, reliable, and accessible to the neurosurgeon. VHAs have demonstrated utility in guiding intraoperative blood product transfusion, identifying coagulopathy in trauma, and managing postoperative thromboprophylaxis. The first half of this review aims to evaluate and assess VHAs, while the latter half seeks to appraise the evidence supporting their use in neurosurgical populations.

Overpowering posterior lumbar instrumentation and fusion with hyperlordotic anterior lumbar interbody cages followed by posterior revision: a preliminary feasibility study

OBJECTIVE The authors' aim in this study was to evaluate whether sagittal plane correction can be obtained from the front by overpowering previous posterior instrumentation and/or fusion with hyperlordotic anterior lumbar interbody fusion (ALIF) cages in patients undergoing revision surgery for degenerative spinal conditions and/or spinal deformities. METHODS The authors report their experience with the application of hyperlordotic cages at 36 lumbar levels for ALIFs in a series of 20 patients who underwent revision spinal surgery at a single institution. Included patients underwent staged front-back procedures: ALIFs with hyperlordotic cages (12°, 20°, and 30°) followed by removal of posterior instrumentation and reinstrumentation from the back. Patients were divided into the following 2 groups depending on the extent of posterior instrumentation and fusion during the second stage: long constructs (≥ 6 levels with extension into thoracic spine and/or pelvis) and short constructs (< 6 levels). Preoperative and postoperative standing radiographs were evaluated to measure segmental lordosis (SL) along with standard sagittal parameters. Radiographic signs of pseudarthrosis at previously fused levels were also sought in all patients. RESULTS The average patient age was 54 years (range 30-66 years). The mean follow-up was 11.5 months (range 5-26 months). The mean SL achieved with 12°, 20°, and 30° cages was 13.1°, 19°, and 22.4°, respectively. The increase in postoperative SL at the respective surgically treated levels for 12°, 20°, and 30° cages that were used to overpower posterior instrumentation/fusion averaged 6.1° (p < 0.05), 12.5° (p < 0.05), and 17.7° (p < 0.05), respectively. No statistically significant difference was found in SL correction at levels in patients who had pseudarthrosis (n = 18) versus those who did not (n = 18). The mean overall lumbar lordosis increased from 44.3° to 59.8° (p < 0.05). In the long-construct group, the mean improvement in sagittal vertical axis was 85.5 mm (range 19-249.3 mm, p < 0.05). Endplate impaction/collapse was noted in 3 of 36 levels (8.3%). The anterior complication rate was 13.3%. No neurological complications or vascular injuries were observed. CONCLUSIONS ALIF in which hyperlordotic cages are used to overpower posterior spinal instrumentation and fusion can be expected to produce an increase in SL of a magnitude that is roughly half of the in-built cage lordotic angle. This technique may be particularly suited for lordosis correction from the front at lumbar levels that have pseudarthrosis from the previous posterior spinal fusion. Meticulous selection of levels for ALIF is crucial for safely and effectively performing this technique.

Novel Index to Quantify the Risk of Surgery in the Setting of Adult Spinal Deformity: A Study on 10,912 Patients From the Nationwide Inpatient Sample

STUDY DESIGN

Retrospective review of the Nationwide Inpatient Sample from 2001 to 2010, a prospectively collected national database.

OBJECTIVE

Structure an index to quantify adult spinal deformity (ASD) surgical risk based on risk factors for medical complications, surgical complications, revisions (R), mortality (M) rates, and length of hospital stay.

SUMMARY OF BACKGROUND DATA

Evidence supporting ASD surgery cost-effectiveness and anticipating surgical risk is critical to evaluate the risk/benefit balance of such treatment for patients.

MATERIALS AND METHODS

Discharges ages 25+, 4+ levels fused, diagnoses specific for scoliosis, and refusions. Five multivariate models determined independent risk factors that increased the risk of ≥1 for medical complications, surgical complications, R, M, and length of hospital stay. Models controlled for age, sex, race, revision status, surgical approach, levels fused, and osteotomy utilization. Odds ratios (ORs) were weighted using Nationwide Inpatient Sample weight files and based on their predictive category: 2 times for revision predictors and 4 times for mortality predictors. Predictors with OR≥1.5 were considered clinically relevant. Fifty points were distributed among the predictors based on their accumulative OR to establish a risk index.

RESULTS

A total of 10,912 ASD discharges were identified (mean age: 62 y; 73% females; 14% revision cases). The structured risk index incorporated the following factors based on accumulative ORs: pulmonary circulation disorder (42.05), drug abuse (21.86), congestive heart failure (15.25), neurological disorder (17.31), alcohol abuse (13.24), renal failure (11.64), age>65 (12.28), coagulopathy (11.65), level +9 (6.7), revision (3.35), and osteotomy (3). These risk factors were scored: 14, 7, 5, 5, 4, 4, 4, 4, 2, 1, 1, respectively. Three risk thresholds were proposed: mild (0-10), moderate (10-20), severe >20/50 points.

CONCLUSIONS

This study proposes an index to quantify the possible risk of morbidity before ASD surgery that will help patients, health insurance companies, and socioeconomic studies in assessing surgical risk/benefits.

LEVEL OF EVIDENCE

Level III.

Results of the 2015 Scoliosis Research Society Survey on Single Versus Dual Attending Surgeon Approach for Adult Spinal Deformity Surgery

STUDY DESIGN

An electronic survey administered to Scoliosis Research Society (SRS) membership.

OBJECTIVE

To characterize surgeon practices and views regarding the use of two attending surgeons for adult spinal deformity (ASD) surgery.

SUMMARY OF BACKGROUND DATA

The use of two experienced attending surgeons can decrease the operative time, estimated blood loss, and perioperative complication rates. However, the current practice patterns for the use of two attending surgeons remains unknown.

METHODS

An electronic, 27-question survey regarding single/dual attending surgeons was administered to the SRS membership. Determinants included: surgeon/practice demographics, assistant type/level of training, and questions regarding use of two attending surgeons. Overall reporting and comparisons between groups were made: US versus international, academic versus private practice, and experience <15 years versus >15 years.

RESULTS

A total of 199 surgeons responded from 27 different countries. Overall and between the groups, the respondents significantly reported believing that two attending spine surgeons improves safety, decreases complications, and improves outcomes (P < 0.01). Approximately, 67.3% reported using a second attending ≤25% of the time (33.2% do not), and 24.1% use one ≥51% of the time (similar between groups); 51.1% that have a second attending feel it's limited by reimbursement and access concerns and 71.9% have difficulty getting the second attending reimbursed. 72.3% use a second attending for ALL of the following reasons (no difference between groups): "it's safer/reduces complications," "it decreases operative time," "it decreases blood loss," "it results in improved outcomes," "it's less work and stress for me." If reimbursement was equal/assured for a second attending, 67.5% would use one "more often" or "always."

CONCLUSION

The respondents feel that having a second attending surgeon improves patient care, however most do not use one often. Reasons include reimbursement/access concerns and the majority would use one if reimbursement was equal and assured. Based on the current literature and these results, there is a need for working with third party payers to improve dual surgeon reimbursement rates in complex cases.

LEVEL OF EVIDENCE

5.

Development of a preoperative predictive model for major complications following adult spinal deformity surgery

OBJECTIVE The operative management of patients with adult spinal deformity (ASD) has a high complication rate and it remains unknown whether baseline patient characteristics and surgical variables can predict early complications (intraoperative and perioperative [within 6 weeks]). The development of an accurate preoperative predictive model can aid in patient counseling, shared decision making, and improved surgical planning. The purpose of this study was to develop a model based on baseline demographic, radiographic, and surgical factors that can predict if patients will sustain an intraoperative or perioperative major complication. METHODS This study was a retrospective analysis of a prospective, multicenter ASD database. The inclusion criteria were age ≥ 18 years and the presence of ASD. In total, 45 variables were used in the initial training of the model including demographic data, comorbidities, modifiable surgical variables, baseline health-related quality of life, and coronal and sagittal radiographic parameters. Patients were grouped as either having at least 1 major intraoperative or perioperative complication (COMP group) or not (NOCOMP group). An ensemble of decision trees was constructed utilizing the C5.0 algorithm with 5 different bootstrapped models. Internal validation was accomplished via a 70/30 data split for training and testing each model, respectively. Overall accuracy, the area under the receiver operating characteristic (AUROC) curve, and predictor importance were calculated. RESULTS Five hundred fifty-seven patients were included: 409 (73.4%) in the NOCOMP group, and 148 (26.6%) in the COMP group. The overall model accuracy was 87.6% correct with an AUROC curve of 0.89 indicating a very good model fit. Twenty variables were determined to be the top predictors (importance ≥ 0.90 as determined by the model) and included (in decreasing importance): age, leg pain, Oswestry Disability Index, number of decompression levels, number of interbody fusion levels, Physical Component Summary of the SF-36, Scoliosis Research Society (SRS)-Schwab coronal curve type, Charlson Comorbidity Index, SRS activity, T-1 pelvic angle, American Society of Anesthesiologists grade, presence of osteoporosis, pelvic tilt, sagittal vertical axis, primary versus revision surgery, SRS pain, SRS total, use of bone morphogenetic protein, use of iliac crest graft, and pelvic incidence-lumbar lordosis mismatch. CONCLUSIONS A successful model (87% accuracy, 0.89 AUROC curve) was built predicting major intraoperative or perioperative complications following ASD surgery. This model can provide the foundation toward improved education and point-of-care decision making for patients undergoing ASD surgery.

Predicting Extended Length of Hospital Stay in an Adult Spinal Deformity Surgical Population

STUDY DESIGN

A retrospective review of a prospective multicenter database.

OBJECTIVE

The aim of this study was to identify variables associated with extended length of stay (ExtLOS) and this impact on health-related quality of life (HRQoL) scores in adult spinal deformity (ASD) patients.

SUMMARY OF BACKGROUND DATA

ASD surgery is complex and associated with complications including extLOS. Although variables contributing to extLOS have been considered, specific complications and pre-disposing factors among ASD surgical patients remain to be investigated.

INCLUSION CRITERIA

ASD surgical patients (age >18 years, scoliosis ≥20°, sagittal vertical axis ≥5 cm, pelvic tilt ≥25°, and/or thoracic kyphosis >60°) with complete demographic, radiographic, and HRQoL data at baseline, 6 weeks, and 2 years postoperative. ExtLOS was based on 75th percentile (≥9 days). Univariate and multivariate analyses identified predictors and evaluated effects on outcomes. Repeated-measures mixed models analyzed impact of ExtLOS on HRQoL [Oswestry Disability Index; Short Form-36 physical component summary/mental component summary; SRS22r Activity (AC), Pain (P), Appearance (AP), Satisfaction (S), Mental (M) and Total (T)].

RESULTS

Three hundred eighty patients met inclusion criteria: 105 (27.6%) had extLOS (≥9 days) and 275 (72.4%) did not. Average LOS was 8 days (range: 1-30 days). Age [odds ratio (OR) 1.04], no. of levels fused (OR 1.12), no. of infections (OR 2.29), no. of neurologic complications (OR 2.51), Charlson Comorbidity Index Score (CCI) predicted ExtLOS (OR 3.92), and no. of intraop complications predicted ExtLOS (OR 3.56). ExtLOS patients had more intracardiopulmonary (pleural effusion: 1.9% vs. 0%) and operative complications (dural tear: 13.3% vs. 5.1%; excessive blood loss: 18% vs. 5.8%) (P < 0.022). At 2 years, both groups of patients experienced an overall improvement in all HRQoL scores (P < 0.001). ExtLOS patients had significantly less overall improvement in all HRQoLs (P < 0.01) except for MCS (P = 0.17) and SRS M (P = 0.08).

CONCLUSION

Extended LOS of ASD patients is affected by comorbidities (higher CCI) and number of intraoperative, but not peri-operative, complications. All patients improved overall in HRQoL scores, but extended LOS patients improved less overall at 2 years in comparison.

LEVEL OF EVIDENCE

3.

Adult Spinal Deformity: Epidemiology, Health Impact, Evaluation, and Management

Spinal deformity in the adult is a common medical disorder with a significant and measurable impact on health-related quality of life. The ability to measure and quantify patient self-reported health status with disease-specific and general health status measures, and to correlate health status with radiographic and clinical measures of spinal deformity, has enabled significant advances in the assessment of the impact of deformity on our population, and in the evaluation and management of spinal deformity using an evidence-based approach. There has been a significant paradigm shift in the evaluation and management of patients with adult deformity. The paradigm shift includes development of validated, disease-specific measures of health status, recognition of deformity in the sagittal plane as a primary determinant of health status, and information on results of operative and medical/interventional management strategies for adults with spinal deformity. Since its inception in 1966, the Scoliosis Research Society (SRS) has been an international catalyst for improving the research and care for patients of all ages with spinal deformity. The SRS Adult Spinal Deformity Committee serves the mission of developing and defining an evidence-based approach to the evaluation and management of adult spinal deformity. The purpose of this overview from the SRS Adult Deformity Committee is to provide current information on the epidemiology and impact of adult deformity, and to provide patients, physicians, and policy makers a guide to the evidence-based evaluation and management of patients with adult deformity.

A Comprehensive Review of Complication Rates After Surgery for Adult Deformity: A Reference for Informed Consent

OBJECTIVE

An up-to-date review of recent literatures and a comprehensive reference for informed consent specific to ASD complications is lacking. The goal of the present study was to determine current complication rates after ASD surgery, in order to provide a reference for informed consent as well as to determine differences between three-column and non-three-column osteotomy procedures to aid in shared decision making.

METHODS

A review of the literature was conducted using the PubMed database. Randomized controlled trials, nonrandomized trials, cohort studies, case-control studies, and case series providing postoperative complications published in 2000 or later were included. Complication rates were recorded and calculated for perioperative (both major and minor) and long-term complication rates. Postoperative outcomes were all stratified by surgical procedure (ie, three-column osteotomy and non-three-column osteotomy).

RESULTS

Ninety-three articles were ultimately eligible for analysis. The data of 11,692 patients were extracted; there were 3,646 complications, mean age at surgery was 53.3 years (range: 25-77 years), mean follow-up was 3.49 years (range: 6 weeks-9.7 years), estimated blood loss was 2,161 mL (range: 717-7,034 mL), and the overall mean complication rate was 55%. Specifically, major perioperative complications occurred at a mean rate of 18.5%, minor perioperative complications occurred at a mean rate of 15.7%, and long-term complications occurred at a mean rate of 20.5%. Furthermore, three-column osteotomy resulted in a higher overall complication rate and estimated blood loss than non-three-column osteotomy.

CONCLUSIONS

A review of recent literatures providing complication rates for ASD surgery was performed, providing the most up-to-date incidence of early and late complications. Providers may use such data in helping to counsel patients of the literature-supported complication rates of such procedures despite the planned benefits, thus obtaining a more thorough informed consent.

Rotational thromboelastometry–guided blood product management in major spine surgery

OBJECT

Major spinal surgery in adult patients is often associated with significant intraoperative blood loss. Rotational thromboelastometry (ROTEM) is a functional viscoelastometric method for real-time hemostasis testing. In this study, the authors sought to characterize the coagulation abnormalities encountered in spine surgery and determine whether a ROTEM-guided, protocol-based approach to transfusion reduced blood loss and blood product use and cost.

METHODS

A hospital database was used to identify patients who had undergone adult deformity correction spine surgery with ROTEM-guided therapy. All patients who received ROTEM-guided therapy (ROTEM group) were matched with historical cohorts whose coagulation status had not been evaluated with ROTEM but who were treated using a conventional clinical and point-of-care laboratory approach to transfusion (Conventional group). Both groups were subdivided into 2 groups based on whether they had received intraoperative tranexamic acid (TXA), the only coagulation-modifying medication administered intraoperatively during the study period. In the ROTEM group, 26 patients received TXA (ROTEM-TXA group) and 24 did not (ROTEM-nonTXA group). Demographic, surgical, laboratory, and perioperative transfusion data were recorded. Data were analyzed by rank permutation test, adapted for the 1:2 ROTEM-to-Conventional matching structure, with p < 0.05 considered significant.

RESULTS

Comparison of the 2 groups in which TXA was used showed significantly less fresh-frozen plasma (FFP) use in the ROTEM-TXA group than in the Conventional-TXA group (median 0 units [range 0–4 units] vs 2.5 units [range 0–13 units], p < 0.0002) but significantly more cryoprecipitate use (median 1 unit [range 0–4 units] in the ROTEM-TXA group vs 0 units [range 0–2 units] in the Conventional-TXA group, p < 0.05), with a nonsignificant reduction in blood loss (median 2.6 L [range 0.9–5.4 L] in the ROTEM-TXA group vs 2.9 L [0.7–7.0 L] in the Conventional-TXA group, p = 0.21). In the 2 groups in which TXA was not used, the ROTEM-nonTXA group showed significantly less blood loss than the Conventional-nonTXA group (median 1 L [range 0.2–6.0 L] vs 1.5 L [range 1.0–4.5 L], p = 0.0005), with a trend toward less transfusion of packed red blood cells (pRBC) (median 0 units [range 0–4 units] vs 1 unit [range 0–9 units], p = 0.09]. Cryoprecipitate use was increased and FFP use decreased in response to ROTEM analysis identifying hypofibrinogenemia as a major contributor to ongoing coagulopathy.

CONCLUSIONS

In major spine surgery, ROTEM-guided transfusion allows for standardization of transfusion practices and early identification and treatment of hypofibrinogenemia. Hypofibrinogenemia is an important cause of the coagulopathy encountered during these procedures and aggressive management of this complication is associated with less intraoperative blood loss, reduced transfusion requirements, and decreased transfusion-related cost.

Three-column osteotomy surgery versus standard surgical management for the correction of adult spinal deformity: a cohort study

Background

The aim of this study was to analyze and compare the surgical data, clinical outcomes, and complications between three-column osteotomy (3-COS) and standard surgical management (SSM) for the treatment of adult spine deformity (ASD).

Methods

A total of 112 patients who underwent consecutive 3-COS (n = 48) and SSM (n = 64) procedures for ASD correction at a single institution from 2001 to 2011 were reviewed in this study. The outcomes were assessed using the Scoliosis Research Society (SRS)-22 scores. The complications of patients with 3-COS and SSM were also compared.

Results

No significant differences were found in patient characteristics between SSM and 3-COS groups. Surgical data and radiographic parameters showed that the patients of the 3-COS group suffered more severe ASD than those of the SSM group. The distribution of surgical complications revealed that SSM group underwent more complications than 3-COS groups with no significant differences. At final follow-up, the total SRS-22 score of SSM was not significant between pre-operation and post-operation. However, the total SRS-22 score of 3-COS at final follow-up was significantly higher than pre-operation.

Conclusion

For severe ASD patients with high grade pelvic incidence (PI), pelvic tilt (PT), and PI/lumbar lordosis (LL) mismatch and who have subjected to spine surgeries more than twice before, 3-COS might be more effective than SSM in improving the clinical outcomes. However, due to the higher reoperation rate of 3-COS, SSM may be more appropriate than SSM for correcting the not serious ASD patients.