Neurologic Outcomes of Complex Adult Spinal Deformity Surgery: Results of the Prospective, Multicenter Scoli-RISK-1 Study

Treatment of adult thoracolumbar spinal deformity: past, present, and future

Care of the patient with adult spinal deformity (ASD) has evolved from being primarily supportive to now having the ability to directly treat and correct the spinal pathology. The focus of this narrative literature review is to briefly summarize the history of ASD treatment, discuss the current state of the art of ASD care with focus on surgical treatment and current challenges, and conclude with a discussion of potential developments related to ASD surgery.In the past, care for ASD was primarily based on supportive measures, including braces and assistive devices, with few options for surgical treatments that were often deemed high risk and reserved for rare situations. Advances in anesthetic and critical care, surgical techniques, and instrumentation now enable almost routine surgery for many patients with ASD. Despite the advances, there are many remaining challenges currently impacting the care of ASD patients, including increasing numbers of elderly patients with greater comorbidities, high complication and reoperation rates, and high procedure cost without clearly demonstrated cost-effectiveness based on standard criteria. In addition, there remains considerable variability across multiple aspects of ASD surgery. For example, there is currently very limited ability to provide preoperative individualized counseling regarding optimal treatment approaches (e.g., operative vs nonoperative), complication risks with surgery, durability of surgery, and likelihood of achieving individualized patient goals and satisfaction. Despite the challenges associated with the current state-of-the-art ASD treatment, surgery continues to be a primary option, as multiple reports have demonstrated the potential for surgery to significantly improve pain and disability. The future of ASD care will likely include techniques and technologies to markedly reduce complication rates, including greater use of navigation and robotics, and a shift toward individualized medicine that enables improved counseling, preoperative planning, procedure safety, and patient satisfaction.Advances in the care of ASD patients have been remarkable over the past few decades. The current state of the art enables almost routine surgical treatment for many types of ASD that have the potential to significantly improve pain and disability. However, significant challenges remain, including high complication rates, lack of demonstrated cost-effectiveness, and limited ability to meaningfully counsel patients preoperatively on an individual basis. The future of ASD surgery will require continued improvement of predictability, safety, and sustainability.

Apical Vertebral Column Resection with Sagittal Rotation and Controlled Anterior Opening and Posterior Closing Maneuver for the Treatment of Severe Post-Tubercular Kyphosis: Case Series and Literature Review

Study Design

Retrospective case series.

Purpose

Describe the technique and evaluate the outcome of apical vertebral column resection (VCR) with sagittal rotation and anterior opening and posterior closing (AOPC) maneuver for correction of severe post-tubercular kyphosis (PTK).

Overview of Literature

The surgical procedures described for the correction of PTK are VCR, pedicle subtraction osteotomy, transpedicular decancellation osteotomy, and closing-opening osteotomy.

Methods

We retrospectively evaluated 21 patients who had been operated on with single stage apical VCR with AOPC maneuver. Radiographs were obtained before surgery and at regular follow-up intervals. These were used to calculate the angle of kyphosis. Back pain was rated using the Visual Analog Scale (VAS) and neurological status was graded using Frankel grading. Radiological outcome was assessed by the improvement in the angle of kyphosis and fusion following surgery. Neurological status was assessed using Frankel grading.

Results

The study included eight males and 13 females with a mean age of 21.9 and average follow-up time of 30.4 months. The average number of vertebral bodies destroyed was 2.57. Kyphosis was improved from a mean of 68.42°±13.23° preoperative to 8.71°±4.58° postoperative. The average correction achieved was 87.10%. Preoperative VAS score improved from a mean of 6.38±0.92 preoperative to 1.38±0.49 postoperative. No patients had any sign of neurological deterioration. Seven out of eight patients with a preoperative neurological deficit improved following surgery. Two patients developed superficial wound maceration, one had persistent postoperative hypotension, and the other developed hemothorax. All patients recovered fully without a need for additional surgery.

Conclusions

Single stage simultaneous anterior column lengthening and posterior column shortening is an effective method for surgical correction of severe PTK.

Unilateral versus bilateral lower extremity motor deficit following complex adult spinal deformity surgery: is there a difference in recovery up to 2-year follow-up?

BACKGROUND CONTEXT

Scoli-RISK-1 is a multicenter prospective cohort designed to study neurologic outcomes following complex adult spinal deformity (ASD). The effect of unilateral versus bilateral postoperative motor deficits on the likelihood of long-term recovery has not been previously studied in this population.

PURPOSE

To evaluate whether bilateral postoperative neurologic deficits have a worse recovery than unilateral deficits.

STUDY DESIGN

Secondary analysis of a prospective, multicenter, international cohort study.

METHODS

In a cohort of 272 patients, neurologic decline was defined as deterioration of the American Spinal Injury Association Lower Extremity Motor Scores (LEMS) following surgery. Patients with lower extremity neurologic decline were grouped into unilateral and bilateral cohorts. Differences in demographics, surgical variables, and patient outcome measures between the two cohorts were analyzed.

RESULTS

A total of 265 patients had LEMS completed at discharge. Unilateral decline was seen in 32 patients (12%), while 29 (11%) had bilateral symptoms. At 2 years, there was no significant difference in either median LEMS (unilateral 50.0, interquartile range [IQR] 47.5-50.0; bilateral 50.0, IQR 48.0-50.0, p=.939) or change in LEMS from baseline (unilateral 0.0, IQR -1.0 to 0.0; bilateral 0.0, IQR -1.0 to 0.0, p=.920). In both groups, approximately two-thirds of patients saw recovery to at least their preoperative baseline by 2 years postoperatively (unilateral n=15, 63%; bilateral n=14, 67%). The mean Scoliosis Research Society-22R (SRS-22R) score at 2 years was 3.7±0.6 versus 3.2±0.6 (p=.009) for unilateral and bilateral groups, respectively.

CONCLUSIONS

The prognosis for neurologic recovery of new motor deficits following complex adult spinal deformity is similar with both unilateral and bilateral weaknesses. Despite similar rates of neurologic recovery, patient reported outcomes for those with bilateral motor decline measured by SRS-22R are worse at 2 years after surgery.

The reliability of motor evoked potentials to predict dorsiflexion injuries during lumbosacral deformity surgery: importance of multiple myotomal monitoring

STUDY DESIGN

Case-control analysis of transcranial motor evoked potential (MEP) responses and clinical outcome.

OBJECTIVE

To determine the sensitivity and specificity of MEPs to predict isolated nerve root injury causing dorsiflexion weakness in selected patients having complex lumbar spine surgery.

SUMMARY OF BACKGROUND DATA

The surgical correction of distal lumbar spine deformity involves significant risk for damage to neural structures that control muscles of ankle and toe dorsiflexion. Procedures often include vertebral translation, interbody fusion, and posterior-based osteotomies. The benefit of using MEP monitoring to predict dorsiflexion weakness has not been well-established. The purpose of this paper is to describe the relationship between neural complications from lumbar surgery and intraoperative MEP changes.

METHODS

Included were 542 neurologically intact patients who underwent posterior spinal fusion for the correction of distal lumbar deformity. Two myotomes, including tibialis anterior (TA) and extensor hallucis longus (EHL), were monitored. MEP and free-running electromyography data were assessed in each patient. Cases of new dorsiflexion weakness noted postoperatively were identified. Data in case and control patients were compared. There was no direct funding for this work. The Department of Anesthesiology and Perioperative Care provides salary support for authors one and six. Authors two and three report employment in the field of intraoperative neurophysiological monitoring as a study-specific conflict of interest.

RESULTS

Twenty-five patients (cases) developed dorsiflexion weakness. MEP amplitude decreased in the injured myotomes by an average of 65 ± 21% (TA) and 60±26% (EHL), which was significantly greater than the contralateral uninjured side or for control subjects. (p < .01) Receiver operator characteristic (ROC) curves showed high sensitivity, specificity, and predictive value for changes in MEP amplitude using either the TA or EHL. Analysis of MEP changes to either TA or EHL yielded a superior ROC curve. Net reclassification improvement analysis showed assessing MEP changes to both TA and EHL improved the predictability of injury.

CONCLUSIONS

The use of MEP amplitude change is highly sensitive and specific to predict a new postoperative dorsiflexion injury. Monitoring two myotomes (both TA and EHL) is superior to relying on MEP changes from a single myotome. Electromyography activity was less accurate but compliments MEP use. Additional studies are needed to define optimal intraoperative MEP warning thresholds.

Early and Late Reoperation Rates With Various MIS Techniques for Adult Spinal Deformity Correction

STUDY DESIGN

A multicenter retrospective review of an adult spinal deformity database.

OBJECTIVE

We aimed to characterize reoperation rates and etiologies of adult spinal deformity surgery with circumferential minimally invasive surgery (cMIS) and hybrid (HYB) techniques.

METHODS

Inclusion criteria were age ≥18 years, and one of the following: coronal Cobb >20°, sagittal vertical axis >5 cm, pelvic tilt >20°, and pelvic incidence-lumbar lordosis >10°. Patients with either cMIS or HYB surgery, ≥3 spinal levels treated with 2-year minimum follow-up were included.

RESULTS

A total of 133 patients met inclusion for this study (65 HYB and 68 cMIS). Junctional failure (13.8%) was the most common reason for reoperation in the HYB group, while fixation failure was the most common reason in the cMIS group (14.7%). There was a higher incidence of proximal junctional failure (PJF) than distal junctional failure (DJF) within HYB (12.3% vs 3.1%), but no significant differences in PJF or DJF rates when compared to cMIS. Early (<30 days) reoperations were less common (cMIS = 1.5%; HYB = 6.1%) than late (>30 days) reoperations (cMIS = 26.5%; HYB = 27.7%), but early reoperations were more common in the HYB group after propensity matching, largely due to infection rates (10.8% vs 0%, P = .04).

CONCLUSIONS

Adult spinal deformity correction with cMIS and HYB techniques result in overall reoperation rates of 27.9% and 33.8%, respectively, at minimum 2-year follow-up. Junctional failures are more common after HYB approaches, while pseudarthrosis/fixation failures happen more often with cMIS techniques. Early reoperations were less common than later returns to the operating room in both groups, but cMIS demonstrated less risk of infection and early reoperation when compared with the HYB group.

External Validation of the Adult Spinal Deformity (ASD) Frailty Index (ASD-FI) in the Scoli-RISK-1 Patient Database

STUDY DESIGN

Analysis of a prospective multicenter database.

OBJECTIVE

To assess the ability of the recently created Adult Spinal Deformity (ASD) Frailty Index (ASD-FI) to predict odds of major complications and length of hospital stay for patients who had more severe preoperative deformity and underwent more invasive ASD surgery compared with patients in the database used to create the index.

SUMMARY OF BACKGROUND DATA

Accurate preoperative estimates of risk are necessary given the high complication rates currently associated with ASD surgery.

METHODS

Patients were enrolled by participating institutions in Europe, Asia, and North America from 2009 to 2011. ASD-FI scores were used to classify 267 patients as not frail (NF) (<0.3), frail (0.3-0. 5), or severely frail (SF) (>0.5). Multivariable logistic regression, adjusted for preoperative and surgical covariates such as operative time and blood loss, was performed to determine the relationship between ASD-FI category and incidence of major complications, overall incidence of complications, and length of hospital stay.

RESULTS

The mean ASD-FI score was 0.3 (range, 0-0.7). We categorized 105 patients as NF, 103 as frail, and 59 as SF. The adjusted odds of developing a major complication were higher for SF patients (odds ratio = 4.4; 95% CI 2.0, 9.9) compared with NF patients. After adjusting for covariates, length of hospital stay for SF patients increased by 19% (95% CI 1.4%, 39%) compared with NF patients. The odds of developing a major complication or having increased length of stay were similar between frail and NF patients.

CONCLUSION

Greater patient frailty, as measured by the ASD-FI, is associated with a longer hospital stay and greater risk of major complications among patients who have severe preoperative deformity and undergo invasive surgical procedures.

LEVEL OF EVIDENCE

2.

Incidence and risk factors of postoperative neurologic decline after complex adult spinal deformity surgery: results of the Scoli-RISK-1 study

BACKGROUND CONTEXT

Significant variability in neurologic outcomes after surgical correction for adult spinal deformity (ASD) has been reported. Risk factors for decline in neurologic motor outcomes are poorly understood.

PURPOSE

The objective of the present investigation was to identify the risk factors for postoperative neurologic motor decline in patients undergoing complex ASD surgery.

STUDY DESIGN/SETTING

This is a prospective international multicenter cohort study.

PATIENT SAMPLE

From September 2011 to October 2012, 272 patients undergoing complex ASD surgery were prospectively enrolled in a multicenter, international cohort study in 15 sites.

OUTCOME MEASURES

Neurologic decline was defined as any postoperative deterioration in American Spinal Injury Association lower extremity motor score (LEMS) compared with preoperative status.

METHODS

To identify risk factors, 10 candidate variables were selected for univariable analysis from the dataset based on clinical relevance, and a multivariable logistic regression analysis was used with backward stepwise selection.

RESULTS

Complete datasets on 265 patients were available for analysis and 61 (23%) patients showed a decline in LEMS at discharge. Univariable analysis showed that the key factors associated with postoperative neurologic deterioration included older age, lumbar-level osteotomy, three-column osteotomy, and larger blood loss. Multivariable analysis revealed that older age (odds ratio [OR]=1.5 per 10 years, 95% confidence interval [CI] 1.1-2.1, p=.005), larger coronal deformity angular ratio [DAR] (OR=1.1 per 1 unit, 95% CI 1.0-1.2, p=.037), and lumbar osteotomy (OR=3.3, 95% CI 1.2-9.2, p=.022) were the three major predictors of neurologic decline.

CONCLUSIONS

Twenty-three percent of patients undergoing complex ASD surgery experienced a postoperative neurologic decline. Age, coronal DAR, and lumbar osteotomy were identified as the key contributing factors.

Loss of intraoperative neurological monitoring signals during flexed prone positioning on a hinged open frame during surgery for kyphoscoliosis correction: case report

Various complications of prone positioning in spine surgery have been described in the literature. Patients in the prone position for extended periods are subject to neurological deficits and/or loss of intraoperative signals due to compression neuropathies, but positioning-related spinal deficits are rare in the thoracolumbar deformity population. The authors present a case of severe kyphoscoliotic deformity with critical thoracolumbar stenosis in which, during the use of a hinged open frame in the prone position, complete loss of intraoperative neural monitoring signals occurred while the frame was flexed into kyphosis to facilitate exposure and instrumentation placement. When the frame was reset to a neutral position, evoked potentials returned to baseline and the operation proceeded without complications. This case represents, to the authors’ knowledge, the first report of loss of evoked potentials due to an alteration of prone positioning on a hinged open frame. When positioning patients in such a manner, careful attention should be directed to intraoperative signals in patients with critical stenosis and kyphotic deformity.

An Analysis of the Incidence and Outcomes of Major Versus Minor Neurological Decline After Complex Adult Spinal Deformity Surgery: A Subanalysis of Scoli-RISK-1 Study

STUDY DESIGN

A subanalysis from a prospective, multicenter, international cohort study in 15 sites (Scoli-RISK-1).

OBJECTIVE

To report detailed information regarding the severity of neurological decline related to complex adult spine deformity (ASD) surgery and to examine outcomes based on severity.

SUMMARY OF BACKGROUND DATA

Postoperative neurological decline after ASD surgeries can occur due to nerve root(s) or spinal cord dysfunction. The impact of decline and the pattern of recovery may be related to the anatomic location and the severity of the injury.

METHODS

An investigation of 272 prospectively enrolled complex ASD surgical patients with neurological status measured by American Spinal Injury Association Lower Extremity Motor Scores (LEMS) was undertaken. Postoperative neurological decline was categorized into "major" (≥5 points loss) versus "minor" (<5 points loss) deficits. Timing and extent of recovery in LEMS were investigated for each group.

RESULTS

Among the 265 patients with LEMS available at discharge, 61 patients (23%) had neurological decline, with 20 (33%) experiencing major decline. Of note, 90% of the patients with major decline had deficits in three or more myotomes. Full recovery was seen in 24% at 6 weeks and increased to 65% at 6 months. However, 34% continued to experience some neurological decline at 24 months, with 6% demonstrating no improvement. Of 41 patients (67%) with minor decline, 73% had deficits in one or two myotomes. Full recovery was seen in 49% at 6 weeks and increased to 70% at 6 months. Of note, 26% had persistence of some neurological deficit at 24 months, with 18% demonstrating no recovery.

CONCLUSION

In patients undergoing complex ASD correction, a rate of postoperative neurological decline of 23% was noted with 33% of these being "major." Although most patients showed substantial recovery by 6 months, approximately one-third continued to experience neurological dysfunction.

LEVEL OF EVIDENCE

2.

The use of three-column osteotomy in the treatment of rigid deformities of the adult spine

Objective

To analyze and characterize data about clinical outcome and complication rates in three-column osteotomies (3 CO) for treatment of rigid adult spine deformity (ASD).

Methods

Baseline and postoperative clinical outcomes, considering the Oswestry Disability Index (ODI) and Scoliosis Research Society-22 (SRS-22) questionnaires, radiographic parameters, and demographic data of patients who underwent 3 CO procedure for fixed ASD treatment were collected. Surgical characteristics and reports of perioperative complications were recorded, as well as those that occurred at a minimum follow-up of 12 months.

Results

Ten patients underwent 3 CO and had a minimum follow-up of 12 months (mean 24 months). The patients showed significantly improved health-related quality of life scores (ODI, SRS-22 total, function/activity, pain, and appearance). They also presented a significant improvement in all radiographic parameters considered in the study. Taking into account the surgical procedure, the operative time was significantly higher in patients with staged procedure than in patients with single-stage surgery (p = 0.003), with similar estimated blood loss and complication incidence. There were ten complications in six patients (60%), with a mean of 1.0 complication per patient.

Conclusions

Despite of the high complication rates, 3 CO was an effective technique, considering clinical and radiographic outcomes, to treat complex cases of rigid ASD in a sample of patients operated in a Brazilian spine center, with a minimum follow-up of 12 months.

Classification of Adult Spinal Deformity: Review of Current Concepts and Future Directions

Although adult spinal deformity (ASD) has become a global health problem, the classification system and optimal surgical treatment for ASD is yet to be standardized worldwide. A significant part of the population, as high as 10%, in industrialized societies will be aged above 65 years within the next 10 years. Herein, a systematic review of the scientific literature related to the classification and treatment of ASD was conducted wherein historical to the most recent classifications of ASD were reviewed. By discussing the benefits and limitations of the previous classification systems and considering the factors affecting the clinical outcomes of surgical treatment of ASD, this article would like to propose future directions for the development of a new classification system for ASD.

A novel use of cement as a salvage procedure in patients with complex spinal injuries with proximal junctional failure

Long-construct fixations can be complicated by proximal junctional kyphosis. In elderly, high-risk patients with numerous comorbidities, lengthy surgical times and increased blood loss associated with revision osteotomies and extension of fusions are not often tolerated and pose serious life-threatening risks. We present a salvage technique used in a patient with proximal junctional failure and demonstrate its role in improving symptoms and functionality in those not deemed fit for major surgery. Pre- and postoperative pain scores in accordance with the visual analogue scale, walking distances and radiographs were reviewed in a patient who underwent the salvage technique to ascertain the subjective and objective difference in pain and functionality. The patient showed marked improvement in pain scores and walking distances postoperatively. Additionally, the degree of proximal junctional kyphosis was lower on postoperative radiographs. While holding risks of its own, our described technique can be performed in select cases and is a good salvage procedure in high-risk patients. It prevents their exposure to the risks that accompany large revision operations and fusion models with further potential to fail. We recommend that our technique is performed only at specialist centres.

Health-Related Quality of Life Scores Underestimate the Impact of Major Complications in Lumbar Degenerative Scoliosis Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To examine Charlson Comorbidity Index (CCMI) as a marker for deterioration in health status not reflected in standard Health Related Quality of Life (HRQOL) measures.

SUMMARY OF BACKGROUND DATA

HRQOL has become a primary metric for assessing outcomes following spinal deformity surgery. However, studies have reported limited impact of complications on postoperative HRQOL outcomes.

METHODS

We examined serial CCMI, complications, and HRQOL outcomes for 138 adult lumbar deformity patients treated surgically with a minimum two-year follow-up that included 126 females (91%) with a mean age of 59.8 years (range, 40.2-78.5). Patients with no, minor, or major complications were compared at baseline and at one and two years postoperation.

RESULTS

Minor complications were observed in 26 patients (19%) and major complications in 15 (11%). Major complications included motor deficit (7), deep vein thrombosis (4), and respiratory failure (3). There was no difference in preoperative SF-36 Physical Component Summary or Scoliosis Research Society-22R (SRS-22R) scores among the groups at baseline. Preoperative CCMI was lowest in the No Complication group (3.52 ± 1.70) followed by the Major (4.00 ± 1.13) and Minor Complication groups (4.15 ± 1.71, p = .165). At one year, there was a significantly greater CCMI deterioration in the Major Complication group (0.80 ± 1.01) compared to both the Minor (0.08 ± 0.27) and No Complication groups (0.27 ± 0.47, p < .001). There was no significant difference in SF-36 Physical Component Summary or SRS-22R scores among the three groups. Similar findings were observed at two years.

CONCLUSIONS

Despite similar one- and two-year HRQOL improvement, patients with major complications had greater deterioration in CCMI. As CCMI is predictive of medical and surgical risk, patients who sustained a major complication now carry a greater likelihood of adverse outcomes with future interventions, including any subsequent spinal surgery. Although this increased risk may not alter the patient's perception of his or her current health status, it may be important, and should be recognized as part of the shared decision-making process.

LEVEL OF EVIDENCE

Level II, high-quality prognostic study.

Osteotomies in ankylosing spondylitis: where, how many, and how much?

INTRODUCTION

This article presents the current concepts of correction of spinal deformity in ankylosing spondylitis (AS) patients. Untreated AS can be a debilitating disease. In a few patients, disease progression results in severe spinal deformity affecting not only the thoracolumbar, but also the cervical spine. Surgery for correction in AS patients has a long history. With the advent of modern instrumentation, standardization of surgical and anesthesiologic techniques, surgical safety and corrective results could be improved and experiences from lumbar osteotomies could be transferred to the cervical spine.

METHODS

This article presents the current concepts of correction of spinal deformity in AS patients. In particular, questions regarding the localization and number of osteotomies, the optimal surgical target angle as well as planning and prediction of postoperative alignment are discussed.

RESULTS

Insight into recent technical developments, current challenges with correction and geometric analysis of center of rotation (COR) in cervical 3-column osteotomies (3CO) will be presented.

CONCLUSION

The article should encourage readers to improve surgical correction efficacy and provide a better understanding of correction geometry in 3CO for thoracolumbar and cervical spinal deformities.

The 2017 AANS Presidential Address. A world of innovation

The 2016 scientific meeting of the American Association of Neurological Surgeons (AANS) focused on the theme “A World of Innovation.” In his presidential address, 2016 AANS President Frederick Boop compared the historical development of the specialty of neurological surgery with that of the development of global communications. In the early years, general surgeons training in the United States would spend post-residency time abroad learning from surgical masters in Europe and other places. Since Harvey Cushing’s day, neurosurgeons from around the world continue to travel abroad, with many now coming to America for training at centers of excellence.

Current clinical practice is defined by multi-national, multi-center clinical trials, and the AANS subsidiary NeuroPoint Alliance has positioned itself to serve as an international center for the oversight of such trials. The Neurosurgery Research & Education Foundation and the Journal of Neurosurgery Publishing Group have made it possible for a neurosurgeon anywhere with Internet access to learn relevant surgical anatomy, learn new neurosurgical procedures, and watch masters in the field perform operations via high-definition surgical videos at no cost via learning platforms such as the Rhoton Collection, the Neurosurgical Atlas, and Neurosurgical Focus video supplements. At the same time, patients are now traveling abroad to seek medical specialty care. Although the globalization of health care poses certain threats, it also presents neurosurgeons with a world of opportunities.

Health-related quality of life outcomes in complex adult spinal deformity surgery

OBJECTIVE Significant health-related quality of life (HRQOL) benefits have been observed for patients undergoing primary and revision adult spinal deformity (ASD) surgery. The purpose of this study was to report changes in HRQOL measures in a consecutive series of patients undergoing complex spinal reconstructive surgery, using Scoli-RISK-1 (SR-1) inclusion criteria. METHODS This was a single-center, retrospective cohort study. The SR-1 inclusion criteria were used to define patients with complex ASD treated between June 1, 2009, and June 1, 2011. Standard preoperative and perioperative data were collected, including the Scoliosis Research Society (SRS)-22r instrument. The HRQOL changes were evaluated at a minimum 2-year follow-up. Standardized forms were used to collect surgery-related complications data for all patients. Complications were defined as minor, transient major, or permanent major. Patients who achieved a minimum 2-year follow-up were included in the analysis. RESULTS Eighty-four patients meeting SR-1 criteria were identified. Baseline demographic and surgical data were available for 74/84 (88%) patients. Forty-seven of 74 (64%) patients met the additional HRQOL criteria with a minimum 2-year follow-up (mean follow-up 3.4 years, range 2-6.5 years). Twenty-one percent of patients underwent posterior fusion only, 40% of patients had a posterior column osteotomy, and 38% had a 3-column osteotomy. Seventy-five percent of patients underwent a revision procedure. Significant improvements were observed in all SRS-22r domains: Pain: +0.8 (p < 0.001); Self-Image: +1.4 (p < 0.001); Function: +0.46 (p < 0.001); Satisfaction: +1.6 (p < 0.001); and Mental Health: +0.28 (p = 0.04). With the exception of Mental Health, more than 50% of patients achieved a minimum clinically important difference (MCID) in SRS-22r domain scores (Mental Health: 20/47, 42.6%). A total of 65 complications occurred in 31 patients. This includes 29.8% (14/47) of patients who suffered a major complication and 17% (8/47) who suffered a postoperative neurological deficit, most commonly at the root level (10.6%, 5/47). Of the 8 patients who suffered a neurological deficit, 1 (13%) was able to achieve MCID in the SRS Function domain. CONCLUSIONS The majority of patients experienced clinically relevant improvement in SRS-22r HRQOL scores after complex ASD surgery. The greatest improvements were seen in the SRS Pain and SRS Self-Image domains. Although 30% of patients suffered a major or permanent complication, benefits from surgery were still attained. Patients sustaining a neurological deficit or major complication were unlikely to achieve HRQOL improvements meeting or exceeding MCID for the SRS Function domain.

Retrospective analysis underestimates neurological deficits in complex spinal deformity surgery: a Scoli-RISK-1 Study

OBJECTIVE

The authors conducted a study to compare neurological deficit rates associated with complex adult spinal deformity (ASD) surgery when recorded in retrospective and prospective studies. Retrospective studies may underreport neurological deficits due to selection, detection, and recall biases. Prospective studies are expensive and more difficult to perform, but they likely provide more accurate estimates of new neurological deficit rates.

METHODS

New neurological deficits were recorded in a prospective study of complex ASD surgeries (pSR1) with a defined outcomes measure (decrement in American Spinal Injury Association lower-extremity motor score) for neurological deficits. Using identical inclusion criteria and a subset of participating surgeons, a retrospective study was created (rSR1) and neurological deficit rates were collected. Continuous variables were compared with the Student t-test, with correction for multiple comparisons. Neurological deficit rates were compared using the Mantel-Haenszel method for standardized risks. Statistical significance for the primary outcome measure was p < 0.05.

RESULTS

Overall, 272 patients were enrolled in pSR1 and 207 patients were enrolled in rSR1. Inclusion criteria, defining complex spinal deformities, and exclusion criteria were identical. Sagittal Cobb measurements were higher in pSR1, although sagittal alignment was similar. Preoperative neurological deficit rates were similar in the groups. Three-column osteotomies were more common in pSR1, particularly vertebral column resection. New neurological deficits were more common in pSR1 (pSR1 17.3% [95% CI 12.6–22.2] and rSR1 9.0% [95% CI 5.0–13.0]; p = 0.01). The majority of deficits in both studies were at the nerve root level, and the distribution of level of injury was similar.

CONCLUSIONS

New neurological deficit rates were nearly twice as high in the prospective study than the retrospective study with identical inclusion criteria. These findings validate concerns regarding retrospective cohort studies and confirm the need for and value of carefully designed prospective, observational cohort studies in ASD.

The Need for Clinical Practice Guidelines in Assessing and Managing Perioperative Neurologic Deficit: Results from a Survey of the AOSpine International Community

OBJECTIVES

There is no standardized approach to assess and manage perioperative neurologic deficit (PND) in patients undergoing spinal surgery. This survey aimed to evaluate the awareness and usage of clinical practice guidelines (CPGs) as well as investigate how surgeons performing spine surgeries feel about and manage PND and how they perceive the value of developing CPGs for the management of PND.

METHODS

An invitation to participate was sent to the AOSpine International community. Questions were related to the awareness, usage of CPGs, and demographics. Results from the entire sample and subgroups were analyzed.

RESULTS

Of 770 respondents, 659 (85.6%) reported being aware of the existence of guideline(s), and among those, 578 (87.7%) acknowledged using guideline(s). Overall, 58.8% of surgeons reported not feeling comfortable managing a patient who wakes up quadriplegic after an uneventful multilevel posterior cervical decompression with instrumented fusion. Although 22.9% would consider an immediate return to the operating room, the other 77.1% favored conducting some kind of investigation/medical intervention first, such as performing magnetic resonance imaging (85.9%), administrating high-dose corticosteroids (50.2%), or increasing the mean arterial pressure (44.7%). Overall, 90.6% of surgeons believed that CPGs for the management of PND would be useful and 94.4% would be either likely or extremely likely to use these CPGs in their clinical practice.

CONCLUSIONS

Most respondents are aware and routinely use CPGs in their practice. Most surgeons performing spine surgeries reported not feeling comfortable managing PND. However, they highly value the creation and are likely to use CPGs in its management.

Measuring outcomes in adult spinal deformity surgery: a systematic review to identify current strengths, weaknesses and gaps in patient-reported outcome measures

PURPOSE

Adult spinal deformity (ASD) causes severe disability, reduces overall quality of life, and results in a substantial societal burden of disease. As healthcare is becoming more value based, and to facilitate global benchmarking, it is critical to identify and standardize patient-reported outcome measures (PROMs). This study aims to identify the current strengths, weaknesses, and gaps in PROMs used for ASD.

METHODS

Studies were included following a systematic search in multiple bibliographic databases between 2000 and 2015. PROMs were extracted and linked to the outcome domains of WHO's International Classification of Functioning and Health (ICF) framework. Subsequently, the clinimetric quality of identified PROMs was evaluated.

RESULTS

The literature search identified 144 papers that met the inclusion criteria, and nine frequently used PROMs were identified. These covered 29 ICF outcome domains, which could be grouped into three of the four main ICF chapters: body function (n = 7), activity and participation (n = 19), environmental factors (n = 3), and body structure (n = 0). A low quantity (n = 3) of papers was identified that studied the clinimetric quality of PROMs. The Scoliosis Research Society (SRS)-22 has the highest level of clinimetric quality for ASD.

CONCLUSIONS

Outcome domains related to mobility and pain were well represented. We identified a gap in current outcome measures regarding neurological and pulmonary function. In addition, no outcome domains were measured in the ICF chapter body structure. These results will serve as a foundation for the process of seeking international consensus on a standard set of outcome domains, accompanied PROMs and contributing factors to be used in future clinical trials and spine registries.

Predictors of Health-Related Quality-of-Life After Complex Adult Spinal Deformity Surgery: A Scoli-RISK-1 Secondary Analysis

STUDY DESIGN

Longitudinal cohort.

OBJECTIVES

To identify variables that predict 2-year Short Form-36 Physical Composite Summary Score (SF-36PCS) and the Scoliosis Research Society-22R (SRS22-R) Total score after surgery for complex adult spinal deformity.

SUMMARY OF BACKGROUND DATA

Increasingly, treatment effectiveness is assessed by the extent to which the procedure improves a patient's health-related quality of life (HRQOL). This is especially true in patients with complex adult spinal deformity.

METHODS

The data set from the Scoli-Risk-1 study was queried for patients with complete 2-year SF-36 and SRS-22R. Regression analysis was performed to determine predictors of 2-year SF-36PCS and SRS-22R Total scores. Factors included were sex, age, smoking status, body mass index, American Society of Anesthesiologists (ASA) grade, Lower Extremity Motor Score improvement, indication for surgery, preoperative and 2-year maximum coronal Cobb angles, number of prior spine surgeries, number of three-column osteotomies, number of surgical levels, number of surgical stages, lowest instrumented level, presence and type of neurologic complication, and number of reported serious adverse events.

RESULTS

Of 272 cases enrolled, 206 (76%) cases were included in this analysis, 143 (69%) females, and mean age of 57.69 years. Factors that were significantly associated with of 2-year SF-36PCS were age (p < .001), ASA grade (p < .001), maximum preoperative Cobb angle (p = .007), number of three-column osteotomies (p = .049) and type of neurologic complication (p = .068). Factors predictive of 2-year SRS-22R Total scores were maximum preoperative Cobb angle (p = .001) and the number of serious adverse events (p = .071).

CONCLUSIONS

Factors predictive of lower 2-year HRQOLs after surgery for complex adult spinal deformity were older age, higher ASA grade, larger preoperative Cobb angle, larger numbers of three-column osteotomies, and the occurrence of both neurologic and nonneurologic complications. Most of these factors are beyond the control of surgeons. Still, surgeons should medically optimize a patient prior to surgery to minimize the risk of complications and offer the best chance of improving a patient's quality of life.

LEVEL OF EVIDENCE

Level II. Prospective cohort.

Recent and Emerging Advances in Spinal Deformity

BACKGROUND: Over the last several decades, significant advances have occurred in the assessment and management of spinal deformity.

OBJECTIVE: The primary focus of this narrative review is on recent advances in adult thoracic, thoracolumbar, and lumbar deformities, with additional discussions of advances in cervical deformity and pediatric deformity.

METHODS: A review of recent literature was conducted.

RESULTS: Advances in adult thoracic, thoracolumbar, and lumbar deformities reviewed include the growing applications of stereoradiography, development of new radiographic measures and improved understanding of radiographic alignment objectives, increasingly sophisticated tools for radiographic analysis, strategies to reduce the occurrence of common complications, and advances in minimally invasive techniques. In addition, discussion is provided on the rapidly advancing applications of predictive analytics and outcomes assessments that are intended to improve the ability to predict risk and outcomes. Advances in the rapidly evolving field of cervical deformity focus on better understanding of how cervical alignment is impacted by thoracolumbar regional alignment and global alignment and how this can affect surgical planning. Discussion is also provided on initial progress toward development of a comprehensive cervical deformity classification system. Pediatric deformity assessment has been substantially improved with low radiation-based 3-D imaging, and promising clinical outcomes data are beginning to emerge on the use of growth-friendly implants.

CONCLUSION: It is ultimately through the reviewed and other recent and ongoing advances that care for patients with spinal deformity will continue to evolve, enabling better informed treatment decisions, more meaningful patient counseling, reduced complications, and achievement of desired clinical outcomes.

Complication rates associated with 3-column osteotomy in 82 adult spinal deformity patients: retrospective review of a prospectively collected multicenter consecutive series with 2-year follow-up

OBJECTIVE Although 3-column osteotomy (3CO) can provide powerful alignment correction in adult spinal deformity (ASD), these procedures are complex and associated with high complication rates. The authors' objective was to assess complications associated with ASD surgery that included 3CO based on a prospectively collected multicenter database. METHODS This study is a retrospective review of a prospectively collected multicenter consecutive case registry. ASD patients treated with 3CO and eligible for 2-year follow-up were identified from a prospectively collected multicenter ASD database. Early (≤ 6 weeks after surgery) and delayed (> 6 weeks after surgery) complications were collected using standardized forms and on-site coordinators. RESULTS Of 106 ASD patients treated with 3CO, 82 (77%; 68 treated with pedicle subtraction osteotomy [PSO] and 14 treated with vertebral column resection [VCR]) had 2-year follow-up (76% women, mean age 60.7 years, previous spine fusion in 80%). The mean number of posterior fusion levels was 12.9, and 17% also had an anterior fusion. A total of 76 early (44 minor, 32 major) and 66 delayed (13 minor, 53 major) complications were reported, with 41 patients (50.0%) and 45 patients (54.9%) affected, respectively. Overall, 64 patients (78.0%) had at least 1 complication, and 50 (61.0%) had at least 1 major complication. The most common complications were rod breakage (31.7%), dural tear (20.7%), radiculopathy (9.8%), motor deficit (9.8%), proximal junctional kyphosis (PJK, 9.8%), pleural effusion (8.5%), and deep wound infection (7.3%). Compared with patients who did not experience early or delayed complications, those who had these complications did not differ significantly with regard to age, sex, body mass index, Charlson Comorbidity Index, American Society of Anesthesiologists score, smoking status, history of previous spine surgery or spine fusion, or whether the 3CO performed was a PSO or VCR (p ≥ 0.06). Twenty-seven (33%) patients had 1-11 reoperations (total of 44 reoperations). The most common indications for reoperation were rod breakage (n = 14), deep wound infection (n = 15), and PJK (n = 6). The 24 patients who did not achieve 2-year follow-up had a mean of 0.85 years of follow-up, and the types of early and delayed complications encountered in these 24 patients were comparable to those encountered in the patients that achieved 2-year follow-up. CONCLUSIONS Among 82 ASD patients treated with 3CO, 64 (78.0%) had at least 1 early or delayed complication (57 minor, 85 major). The most common complications were instrumentation failure, dural tear, new neurological deficit, PJK, pleural effusion, and deep wound infection. None of the assessed demographic or surgical parameters were significantly associated with the occurrence of complications. These data may prove useful for surgical planning, patient counseling, and efforts to improve the safety and cost-effectiveness of these procedures.

Neurological complications in adult spinal deformity surgery

The number of surgeries performed for adult spinal deformity (ASD) has been increasing due to an aging population, longer life expectancy, and studies supporting an improvement in health-related quality of life scores after operative intervention. However, medical and surgical complication rates remain high, and neurological complications such as spinal cord injury and motor deficits can be especially debilitating to patients. Several independent factors potentially influence the likelihood of neurological complications including surgical approach (anterior, lateral, or posterior), use of osteotomies, thoracic hyperkyphosis, spinal region, patient characteristics, and revision surgery status. The majority of ASD surgeries are performed by a posterior approach to the thoracic and/or lumbar spine, but anterior and lateral approaches are commonly performed and are associated with unique neural complications such as femoral nerve palsy and lumbar plexus injuries. Spinal morphology, such as that of hyperkyphosis, has been reported to be a risk factor for complications in addition to three-column osteotomies, which are often utilized to correct large deformities. Additionally, revision surgeries are common in ASD and these patients are at an increased risk of procedure-related complications and nervous system injury. Patient selection, surgical technique, and use of intraoperative neuromonitoring may reduce the incidence of complications and optimize outcomes.