Early complications in spine surgery and relation to preoperative diagnosis: a single-center prospective study

Revision Lumbar Spine Surgeries: An Early Career Neurosurgery Experience

BACKGROUND

The aims and ambitions of a surgeon in the early years of his professional career are to make a good reputation by providing excellent patient outcomes and avoiding complex and difficult surgeries. Revision lumbar spine surgeries (RLSSs) pose a significant challenge in terms of surgical management, as the moribund anatomy increases the risk of complications, adding to an unlikely outcome.

OBJECTIVE

We conducted this study to determine the clinical indications and outcomes of RLSSs performed by an early career neurosurgeon.

MATERIALS AND METHODS

This cross-sectional study was conducted after approval from the hospital's ethical committee, and data was collected in late December of 2022 and early January 2023, from retrospective records for a single early career neurosurgeon. A form was filled with each patient's data, such as age, gender, time since surgery, indication for surgery, operative findings, types of surgery performed, etc. All variables were noted for the patient and were further categorized, based on the clinical records, into many sub-categories.

RESULTS

Almost 400 lumbar spine surgeries were performed by the surgeon, and about 45 (11.25%) were revision surgeries, and the full record was available for 42 surgeries. These patients' ages ranged from 22 to 70 years, and the mean age was about 46.74±13.29 SD. The common symptoms leading to revision surgeries were numbness and pain in 17 (40.5%) patients each; common per-operative findings were recurrent disc in eight patients (19%), infection in nine patients (21.4%), and fibrosis/adhesions in 16 (38.1%); most common surgeries performed were diskectomy in 11 (26.2%) and diskectomy plus release of adhesions in 12 (28.6%); complications occurred in 14 (33%), and good to excellent outcomes was recorded in 29 (69%) cases.  Conclusion: RLSSs are difficult compared to first-time lumbar spine surgeries, and the moribund anatomy predisposes to complications, and better shall be dealt with great care and, at the minimum, shall be embarked upon as a team.

Impact of Preoperative Motor Status for the Positive Predictive Value of Transcranial Motor-Evoked Potentials Alerts in Thoracic Spine Surgery: A Prospective Multicenter Study by the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

STUDY DESIGN

Prospective multicenter study.

OBJECTIVE

To investigate the validity of transcranial motor-evoked potentials (Tc-MEP) in thoracic spine surgery and evaluate the impact of specific factors associated with positive predictive value (PPV).

METHODS

One thousand hundred and fifty-six cases of thoracic spine surgeries were examined by comparing patient backgrounds, disease type, preoperative motor status, and Tc-MEP alert timing. Tc-MEP alerts were defined as an amplitude decrease of more than 70% from the baseline waveform. Factors were compared according to preoperative motor status and the result of Tc-MEP alerts. Factors that showed significant differences were identified by univariate and multivariate analysis.

RESULTS

Overall sensitivity was 91.9% and specificity was 88.4%. The PPV was significantly higher in the preoperative motor deficits group than in the preoperative no-motor deficits group for both high-risk (60.3% vs 38.3%) and non-high-risk surgery groups (35.1% vs 12.8%). In multivariate logistic analysis, the significant factors associated with true positive were surgical maneuvers related to ossification of the posterior longitudinal ligament (odds ratio = 11.88; 95% CI: 3.17-44.55), resection of intradural intramedullary spinal cord tumor (odds ratio = 8.83; 95% CI: 2.89-27), preoperative motor deficit (odds ratio = 3.46; 95% CI: 1.64-7.3) and resection of intradural extramedullary spinal cord tumor (odds ratio = 3.0; 95% CI: 1.16-7.8). The significant factor associated with false positive was non-attributable alerts (odds ratio = .28; 95% CI: .09-.85).

CONCLUSION

Surgeons are strongly encouraged to use Tc-MEP in patients with preoperative motor deficits, regardless of whether they are undergoing high-risk spine surgery or not. Knowledge of PPV characteristics will greatly assist in effective Tc-MEP enforcement and minimize neurological complications with appropriate interventions.

Adverse events in neurosurgery: a comprehensive single-center analysis of a prospectively compiled database

PURPOSE

To prospectively identify and quantify neurosurgical adverse events (AEs) in a tertiary care hospital.

METHODS

From January 2021 to December 2021, all patients treated in our department received a peer-reviewed AE-evaluation form at discharge. An AE was defined as any event after surgery that resulted in an undesirable clinical outcome, which is not caused by the underlying disease, that prolonged patient stay, resulted in readmission, caused a new neurological deficit, required revision surgery or life-saving intervention, or contributed to death. We considered AEs occurring within 30 days after discharge. AEs were categorized in wound event, cerebrospinal fluid (CSF) event, CSF shunt malfunction, post-operative infection, malpositioning of implanted material, new neurological deficit, rebleeding, and surgical goal not achieved and non-neurosurgical AEs.

RESULTS

2874 patients were included. Most procedures were cranial (45.1%), followed by spinal (33.9%), subdural (7.7%), CSF (7.0%), neuromodulation (4.0%), and other (2.3%). In total, there were 621 AEs shared by 532 patients (18.5%). 80 (2.8%) patients had multiple AEs. Most AEs were non-neurosurgical (222; 8.1%). There were 172 (6%) revision surgeries. Patients receiving cranial interventions had the most AEs (19.1%) although revision surgery was only necessary in 3.1% of patients. Subdural interventions had the highest revision rate (12.6%). The majority of fatalities was admitted as an emergency (81/91 patients, 89%). Ten elective patients had lethal complications, six of them related to surgery (0.2%).

CONCLUSION

This study presents the one-year results of a prospectively compiled AE database. Neurosurgical AEs arose in one in five patients. Although the need for revision surgery was low, the rate of AEs highlights the importance of a systematic AE database to deliver continued high-quality in a high-volume center.

Analysis of risk factors for perioperative complications in spine surgery

Complications in spine surgery can arise in the intraoperative or the immediate postoperative period or in a delayed manner. These complications may lead to severe or even permanent morbidity if left undiagnosed and untreated. We prospectively interviewed 526 patients out of 1140 patients who consecutively underwent spinal surgery in our department between November 2017 and November 2018 and analysed the outcome and complication rates. A 12 months follow-up period was also adopted. We analysed the patients' clinical characteristics, comorbidities, surgical management, survival rates, and outcomes. Risk factor analyses for the development of complications were also performed. Patients' median age was 67 years (range: 13-96). The main diagnoses were as follows: degenerative in 50%, tumour in 22%, traumatic fractures in 13%, infections in 10%, reoperations in 3%, and others in 2%. Surgeries were emergency procedures (within 24 h) in 12%. Furthermore, 59% required instrumentation. The overall postoperative complication rate was 26%. Revision surgery was required in 12% of cases within 30 postoperative days (median time to revision 11 days [IQR 5-15 days]). The most frequent complications included wound healing disorders, re-bleeding, and CSF leakage. Thereby, the risk factor analysis revealed age-adjusted CCI (p = 0.01), metastatic tumour (p = 0.01), and atrial fibrillation (p = 0.02) as significant risk factors for postoperative complications. Additionally, postoperative KPS (p = 0.004), postoperative anaemia (p = 0.001), the length of hospital stay (p = 0.02), and duration of surgery (p = 00.002) were also identified as associated factors. Complication rates after spinal surgeries are still high, especially in patients with metastatic tumour disease and poor clinical status (KPS), requiring revision surgeries in several cases. Therefore, specific risk factors should be determined to carefully select surgery groups.

Generalization of fear of movement-related pain and avoidance behavior as predictors of work resumption after back surgery: a study protocol for a prospective study (WABS)

Background

Previous studies indicated that about 20% of the individuals undergoing back surgery are unable to return to work 3 months to 1 year after surgery. The specific factors that predict individual trajectories in postoperative pain, recovery, and work resumption are largely unknown. The aim of this study is to identify modifiable predictors of work resumption after back surgery.

Methods

In this multisite, prospective, longitudinal study, 300 individuals with radicular pain undergoing a lumbar decompression will be followed until 1-year post-surgery. Prior to surgery, participants will perform a computer task to assess fear of movement-related pain, avoidance behavior, and their generalization to novel situations. Before and immediately after surgery, participants will additionally complete questionnaires to assess fear of movement-related pain, avoidance behavior, optimism, expectancies towards recovery and work resumption, and the duration and severity of the pain. Six weeks, 3 months, 6 months, and 12 months after surgery, they will again complete questionnaires to assess sustainable work resumption, pain severity, disability, and quality of life. The primary hypothesis is that (generalization of) fear of movement-related pain and avoidance behavior will negatively affect sustainable work resumption after back surgery. Second, we hypothesize that (generalization of) fear of movement-related pain and avoidance behavior, negative expectancies towards recovery and work resumption, longer pain duration, and more severe pain before the surgery will negatively affect work resumption, pain severity, disability, and quality of life after back surgery. In contrast, optimism and positive expectancies towards recovery and work resumption are expected to predict more favorable work resumption, better quality of life, and lower levels of pain severity and disability after back surgery.

Discussion

With the results of this research, we hope to contribute to the development of strategies for early identification of risk factors and appropriate guidance and interventions before and after back surgery.

Trial registration The study was preregistered on ClinicalTrials.gov: NCT04747860 on February 9, 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40359-022-00736-5.

External validation of a predictive model of adverse events following spine surgery

BACKGROUND CONTEXT

We lack models that reliably predict 30-day postoperative adverse events (AEs) following spine surgery.

PURPOSE

We externally validated a previously developed predictive model for common 30-day adverse events (AEs) after spine surgery.

STUDY DESIGN/SETTING

This prospective cohort study utilizes inpatient and outpatient data from a tertiary academic medical center.

PATIENT SAMPLE

We assessed a prospective cohort of all 276 adult patients undergoing spine surgery in the Department of Neurosurgery at a tertiary academic institution between April 1, 2018 and October 31, 2018. No exclusion criteria were applied.

OUTCOME MEASURES

Incidence of observed AEs was compared with predicted incidence of AEs. Fifteen assessed AEs included: pulmonary complications, congestive heart failure, neurological complications, pneumonia, cardiac dysrhythmia, renal failure, myocardial infarction, wound infection, pulmonary embolus, deep venous thrombosis, wound hematoma, other wound complication, urinary tract infection, delirium, and other infection.

METHODS

Our group previously developed the Risk Assessment Tool for Adverse Events after Spine Surgery (RAT-Spine), a predictive model of AEs within 30 days following spine surgery using a cohort of approximately one million patients from combined Medicare and MarketScan databases. We applied RAT-Spine to the single academic institution prospective cohort by entering each patient's preoperative medical and demographic characteristics and surgical type. The model generated a patient-specific overall risk score ranging from 0 to 1 representing the probability of occurrence of any AE. The predicted risks are presented as absolute percent risk and divided into low (<17%), medium (17%-28%), and high (>28%).

RESULTS

Among the 276 patients followed prospectively, 76 experienced at least one 30-day postoperative AE. Slightly more than half of the cohort were women (53.3%). The median age was slightly lower in the non-AE cohort (63 vs. 66.5 years old). Patients with Medicaid comprised 2.5% of the non-AE cohort and 6.6% of the AE cohort. Spinal fusion was performed in 59.1% of cases, which was comparable across cohorts. There was good agreement between the predicted AE and observed AE rates, Area Under the Curve (AUC) 0.64 (95% CI 0.56-0.710). The incidence of observed AEs in the prospective cohort was 17.8% among the low-risk group, 23.0% in the medium-risk group, and 38.4% in the high risk group (p =.003).

CONCLUSIONS

We externally validated a model for postoperative AEs following spine surgery (RAT-Spine). The results are presented as low-, moderate-, and high-risk designations.

Adverse effects of surgeon performance after a night shift on the incidence of perioperative complications in elective thoracolumbar spine surgery

BACKGROUND

Decline in cognitive function after night shift has been well described. However, in the field of spine surgery, the effect of surgeons' sleeplessness on patient outcome is unclear. The purpose of this study was to investigate whether the risk of perioperative complications in elective thoracolumbar spine surgery could be higher if the surgeon had been on a night shift prior to the day of surgery.

METHODS

We performed a retrospective review of patients who underwent elective posterior thoracolumbar spine surgery, as indicated in medical records, between March 2015 and September 2018. In total, 1189 patients were included and divided into two groups: the post-nighttime (n = 110) and control groups (n = 1079). A post-nighttime case was defined when the operating surgeon was on nighttime duty on the previous night, and other cases were defined as controls. We evaluated the incidence of perioperative complications (surgical site infection, postoperative hematoma, postoperative paralysis, nerve root injury, and dural tear) in both groups.

RESULTS

Overall, we found no significant difference in the major or minor perioperative complication rates between the two groups, but according to the type of complication, the incidence rate of dural tear tended to be higher in the post-nighttime group (13.6% vs 8.2%, P = 0.074). Multivariate analysis showed that post-nighttime status was an independent risk factor of dural tear (adjusted odds ratio, 2.02; 95% confidence interval [CI], 1.10-3.70; P = 0.023). After stratification by surgical complexity, post-nighttime status was an independent risk factor of dural tear only in the surgeries of 3 levels or more (adjusted odds ratio, 2.81; 95% CI, 1.18-6.67; P = 0.019).

CONCLUSIONS

Post-nighttime status was generally not a risk factor of perioperative complications in elective posterior thoracolumbar spine surgeries, but was an independent risk factor of dural tear, especially in complex cases.

Applications of Functionalized Hydrogels in the Regeneration of the Intervertebral Disc

Intervertebral disc degeneration (IDD) is caused by genetics, aging, and environmental factors and is one of the leading causes of low back pain. The treatment of IDD presents many challenges. Hydrogels are biomaterials that possess properties similar to those of the natural extracellular matrix and have significant potential in the field of regenerative medicine. Hydrogels with various functional qualities have recently been used to repair and regenerate diseased intervertebral discs. Here, we review the mechanisms of intervertebral disc homeostasis and degeneration and then discuss the applications of hydrogel-mediated repair and intervertebral disc regeneration. The classification of artificial hydrogels and natural hydrogels is then briefly introduced, followed by an update on the development of functional hydrogels, which include noncellular therapeutic hydrogels, cellular therapeutic hydrogel scaffolds, responsive hydrogels, and multifunctional hydrogels. The challenges faced and future developments of the hydrogels used in IDD are discussed as they further promote their clinical translation.

A Comparison of Mortality and Morbidity Between Complex and Degenerative Spine Surgery in Prospectively Collected Data From 2280 Procedures

Objective

The reported incidence of complications and/or adverse events (AEs) following spine surgery varies greatly. A validated, systematic, reproducible reporting system to quantify AEs was used in 2 prospective cohorts, from 2 spine surgery centers, conducting either complex or purely degenerative spine surgery; in a comparative fashion. The aim was to highlight the differences between 2 distinctly different prospective cohorts with patients from the same background population.

Methods

AEs were registered according to the predefined AE variables in the SAVES (Spine AdVerse Events Severity) system which was used to record all intra- and perioperative AEs. Additional outcomes, including mortality, length of stay, wound infection requiring revision, readmission, and unplanned revision surgery during the index admission, were also registered.

Results

A total of 593 complex and 1,687 degenerative procedures were consecutively included with 100% data completion. There was a significant difference in morbidity when comparing the total number of AEs between the 2 groups (p < 0.001): with a mean number of 1.42 AEs per patient (n = 845) in the complex cohort, and 0.97 AEs per patient (n = 1,630) in the degenerative cohort.

Conclusion

In this prospective study comparing 2 cohorts, we report the rates of AEs related to spine surgery using a validated reproducible grading system for registration. The rates of morbidity and mortality were significantly higher following complex spine surgery compared to surgery for degenerative spine disease.

Morbidity and mortality following degenerative spine surgery in a prospective cohort of 1687 consecutive surgical procedures

STUDY DESIGN

Prospective, observational cohort study.

OBJECTIVE

To determine the true incidence of adverse events (AEs) in European adults undergoing surgery for degenerative spine diseases. The majority of surgeries performed for degenerative spinal diseases are elective, and the need for adequate estimation of risk-benefit of the intended surgery is imperative. A cumbersome obstacle for adequate estimation of surgery-related risks is that the true incidence of complications or adverse events (AEs) remains unclear.

METHODS

All adult patients (≥ 18 years) undergoing spine surgery at a single center from February 1, 2016, to January 31, 2017, were prospectively and consecutively included. Morbidity and mortality were determined using the Spine AdVerse Events Severity (SAVES) system. Additionally, the correlation between the AEs and length of stay (LOS) and mortality was assessed.

RESULTS

A total of 1687 procedures were performed in the study period, and all were included for analysis. Of these, 1399 (83%) were lumbar procedures and 288 (17%) were cervical. The overall incidence of AEs was 47.4%, with a minor AE incidence of 43.2% and a major of 14.5%. Female sex (OR 1.5 [95% CI 1.2-1.9), p < 0.001) and age > 65 years (OR 1.5 [95% CI 1.1-1.7], p = 0.012) were significantly associated with increased odds of having an AE.

CONCLUSION

Based on prospectively registered AEs in this single-center study, we validated the use of the SAVES system in a European population undergoing spine surgery due to degenerative spine disease. We found a higher incidence of AEs than previously reported in retrospective studies. The major AEs registered occurred significantly more often perioperatively and in patients > 65 years.

Spinal surgery complications: an unsolved problem-Is the World Health Organization Safety Surgical Checklist an useful tool to reduce them?

PURPOSE

To investigate whether the World Health Organization Safety Surgical Checklist (SSC) is an effective tool to reduce complications in spinal surgery.

METHODS

We retrospectively evaluated the clinical and radiological charts prospectively collected from patients who underwent a spinal surgery procedure from January 2010 to December 2012. The aim of this study was to compare the incidence of complications between two periods, from January to December 2010 (without checklist) and from January 2011 and December 2012 (with checklist), in order to assess the checklist's effectiveness.

RESULTS

The sample size was 917 patients with an average of 30-month follow-up. The mean age was 52.88 years. The majority of procedures were performed for oncological diseases (54.4%) and degenerative diseases (39.8%). In total, 159 complications were detected (17.3%). The overall incidence of complications for trauma, infectious pathology, oncology, and degenerative disease was 22.2%, 19.2%, 18.4%, and 15.3%, respectively. No correlation was observed between the type of pathology and the complication incidence. We observed a reduction in the overall incidence of complications following the introduction of the SSC: In 2010 without checklist, the incidence of complications was 24.2%, while in 2011 and 2012, following the checklist introduction, the incidence of complications was 16.7% and 11.7%, respectively (mean 14.2%).

CONCLUSIONS

The SSC seems to be an effective tool to reduce complications in spinal surgery. We propose to extend the use of checklist system also to the preoperative and postoperative phases in order to further reduce the incidence of complications. These slides can be retrieved under Electronic Supplementary Material.

A machine learning approach for predictive models of adverse events following spine surgery

BACKGROUND

Rates of adverse events following spine surgery vary widely by patient-, diagnosis-, and procedure-related factors. It is critical to understand the expected rates of complications and to be able to implement targeted efforts at limiting these events.

PURPOSE

To develop and evaluate a set of predictive models for common adverse events after spine surgery.

STUDY DESIGN

A retrospective cohort study.

PATIENT SAMPLES

We extracted 345,510 patients from the Truven MarketScan (MKS) and MarketScan Medicaid Databases and 760,724 patients from the Centers for Medicare and Medicaid Services (CMS) Medicare database who underwent spine surgeries between 2009 and 2013.

OUTCOME MEASURES

Overall adverse event (AE) occurrence and types of AE occurrence during the 30-day postoperative follow-up.

METHODS

We applied a least absolute shrinkage and selection operator regularization method and a logistic regression approach for predicting the risks of an overall AE and the top six most commonly observed AEs. Predictors included patient demographics, location of the spine procedure, comorbidities, type of surgery performed, and preoperative diagnosis.

RESULTS

The median ages of MKS and CMS patients were 49 years and 69, respectively. The most frequent individual AE was a cardiac dysfunction in CMS (10.6%) patients and a pulmonary complication (4.7%) in MKS. The area under the curve (AUC) of a prediction model for an overall AE was 0.7. Among the six individual prediction models, the model for predicting the risk of a pulmonary complication showed the greatest accuracy (AUC 0.76), and the range of AUC for these six models was 0.7 and 0.76. Medicaid status was one of the most important factors in predicting the occurrences of AEs; Medicaid recipients had increased odds of AEs by 20%-60% compared with non-Medicaid patients (odds ratios 1.28-1.6; p<10^-10). Logistic regression showed higher AUCs than least absolute shrinkage and selection operator across these different models.

CONCLUSIONS

We present a set of predictive models for AEs following spine surgery that account for patient-, diagnosis-, and procedure-related factors which can contribute to patient-counseling, accurate risk adjustment, and accurate quality metrics.

Short-term outcomes of lateral lumbar interbody fusion without decompression for the treatment of symptomatic degenerative spondylolisthesis at L4-5

OBJECTIVE Recently, authors have called into question the utility and complication index of the lateral lumbar interbody fusion procedure at the L4-5 level. Furthermore, the need for direct decompression has also been debated. Here, the authors report the clinical and radiographic outcomes of transpsoas lumbar interbody fusion, relying only on indirect decompression to treat patients with neurogenic claudication secondary to Grade 1 and 2 spondylolisthesis at the L4-5 level. METHODS The authors conducted a retrospective evaluation of 18 consecutive patients with Grade 1 or 2 spondylolisthesis from a prospectively maintained database. All patients underwent a transpsoas approach, followed by posterior percutaneous instrumentation without decompression. The Oswestry Disability Index (ODI) and SF-12 were administered during the clinical evaluations. Radiographic evaluation was also performed. The mean follow-up was 6.2 months. RESULTS Fifteen patients with Grade 1 and 3 patients with Grade 2 spondylolisthesis were identified and underwent fusion at a total of 20 levels. The mean operative time was 165 minutes for the combined anterior and posterior phases of the operation. The estimated blood loss was 113 ml. The most common cage width in the anteroposterior dimension was 22 mm (78%). Anterior thigh dysesthesia was identified on detailed sensory evaluation in 6 of 18 patients (33%); all patients experienced resolution within 6 months postoperatively. No patient had lasting sensory loss or motor deficit. The average ODI score improved 26 points by the 6-month follow-up. At the 6-month follow-up, the SF-12 mean Physical and Mental Component Summary scores improved by 11.9% and 9.6%, respectively. No patient required additional decompression postoperatively. CONCLUSIONS This study offers clinical results to establish lateral lumbar interbody fusion as an effective technique for the treatment of Grade 1 or 2 degenerative spondylolisthesis at L4-5. The use of this surgical approach provides a minimally invasive solution that offers excellent arthrodesis rates as well as favorable clinical and radiological outcomes, with low rates of postoperative complications. However, adhering to the techniques of transpsoas lateral surgery, such as minimal table break, an initial look-and-see approach to the psoas, clear identification of the plexus, minimal cranial caudal expansion of the retractor, mobilization of any traversing sensory nerves, and total psoas dilation times less than 20 minutes, ensures the lowest possible complication profile for both visceral and neural injuries even in the narrow safe zones when accessing the L4-5 disc space in patients with degenerative spondylolisthesis.

Prognostic Factors of Neurological Complications in Spinal Surgeries

Study Design

Retrospective study.

Purpose

To determine prognostic factors of neurological complications (NCs) of posterior thoracolumbar surgeries.

Overview of Literature

There have been few reports on the prognosis of NCs according to the causes and treatment methods.

Methods

The subjects were 65 patients who had NCs for 19 years (1995–2013) after posterior thoracolumbar surgeries in Seoul Sacred Heart General Hospital. The degree of neurological injury was assessed using numeric scales as follows: G1, increased leg pain or sensory loss; G2, hemiparesis; G3, paraparesis; G4, cauda equine syndrome; and G5, complete paraplegia. The relative degree of neurological recovery was evaluated using four numeric scales as follows: Gr1, complete recovery; Gr2, almost complete recovery with residual sensory loss or numbness; Gr3, partial recovery with apparent neurological deficit; and Gr4, no recovery. The prognostic factors were investigated in terms of demographic and surgical variables that were available in a retrospective review.

Results

The causes were as follows: epidural hematoma (EH), 25 patients (38.5%); insufficient decompression and fusion, 14 patients (21.5%); mechanical injury, 11 patients (16.9%); insufficient discectomy, four patients (6.2%); and unknown, 11 patients (23.1%). The grade of neurological injury was as follows: G1, 11 patients (16.9%); G2, 34 patients (52.3%); G3, 15 patients (23.1%); G4, three patients (4.6%); and G5, two patients (3.1%). Thirteen patients received conservative treatment, and 52 underwent revision surgeries. Neurological recovery was as follows: Gr1, 21 patients (32.3%); Gr2, 17 patients (26.2%); Gr3, 20 patients (30.8%); and Gr4, seven patients (10.8%). The prognosis depended on the causes (p =0.041). The subgroup analysis of the revision group revealed a significant correlation between the degree of neurological recovery and the timing of revision, irrespective of causes (r =0.413, p =0.002).

Conclusions

The prognosis of NC depended on the causes. EH was the best and unknown was the worst prognostic factor. Revision should be performed as soon as possible for a better prognosis.

High-Risk Surgical Maneuvers for Impending True-Positive Intraoperative Neurologic Monitoring Alerts: Experience in 3139 Consecutive Spine Surgeries

BACKGROUND

Intraoperative neurologic monitoring (IONM) has become an essential component for decreasing the incidence of spinal cord injury during spine surgeries. Many high-risk surgical maneuvers that result in significant IONM alerts have not been reported systematically. Our objective was to thoroughly summarize some common high-risk surgical points associated with IONM alerts in various spine surgeries.

METHODS

Between November 2010 and April 2017, 62 patients with true-positive IONM alerts from 3139 spine surgeries were enrolled. Transcranial motor evoked potentials, somatosensory evoked potentials, and free-run electromyography were used for IONM. All 62 patients were identified as true-positive IONM cases.

RESULTS

Of 3139 patients, 101 demonstrated significant IONM changes-62 true-positive cases, 14 false-positive cases, and 25 indeterminate IONM results. IONM alerts most often occurred in thoracic screw placement (n = 10, 16.1%), osteotomy (n = 22, 35.5%), correction (n = 19, 30.6%), and spinal cord decompression (n = 11, 17.8%). Appropriate timely measures are indicated in response to IONM alerts during high-risk surgical maneuvers. Ten (10/62, 16.1%) patients showed permanent postoperative neurologic deficits.

CONCLUSIONS

IONM alerts are often associated with some specific high-risk surgical maneuvers. Careful and timely observation is crucial.

Risk factors and clinical impact of perioperative neurological deficits following thoracolumbar arthrodesis

Objectives:

The rates of arthrodesis performed in the United States and globally have increased tremendously in the last 10–15 years. Amongst the most devastating complications are neurological deficits including spinal cord injury, nerve root irritation, and cauda equine syndrome. The primary purpose of this study is to understand the risk factors for perioperative neurological deficits in patients undergoing thoracolumbar fusion.

Patients and methods:

Data from the Nationwide Inpatient Sample between the years of 1999–2011 was analyzed. Patients were between the ages of 18 and 80 who had thoracolumbar fusion. Excluded were patients who underwent the procedure as a result of trauma or a malignancy. A list of covariates, including demographic variables, preoperative and postoperative variables that are known to increase the risk of perioperative neurological deficits were compiled. Statistical analysis utilized univariate and multivariate logistic regression for comparisons between these covariates and the proposed outcomes.

Results:

The analysis of 37,899 patients yielded an overall rate of perioperative neurological deficits and mortality of 1.20% and 0.27%, respectively. Risk factors for perioperative neurological deficits included increasing age (OR 1.023 95% CI 1.018–1.029), Van Walraven 5–14 (OR 1.535 95% CI 1.054–2.235), and preoperative paralysis (OR 2.551 95% CI 1.674–3.886). Furthermore, the data showed that being 65 years old or older doubled the risk for perioperative deficit (OR 1.655, CI 1.248–2.194, p < 0.001).

Conclusions:

This population based study found that increasing age, higher comorbid burden, and preoperative paralysis increased the risk of perioperative neurological deficits while female gender and hypertension were found to be protective.

Uninstrumented Posterior Lumbar Interbody Fusion: Have Technological Advances in Stabilizing the Lumbar Spine Truly Improved Outcomes?

BACKGROUND

Since the 1980s, numerous operations have replaced posterior lumbar interbody fusion (PLIF) with human bone. These operations often involve expensive implants and complex procedures. Escalating expenditures in lumbar fusion surgery warrant re-evaluation of classical PLIF with allogeneic ilium and without instrumentation. The purpose of this study was to determine the long-term fusion rate and clinical outcomes of PLIF with allogeneic bone (allo-PLIF).

METHODS

Between 1981 and 2006, 321 patients aged 12-80 years underwent 339 1-level or 2-level allo-PLIFs for degenerative instability and were followed for 1-28 years. Fusion status was determined by radiographs and as available, by computed tomography scans. Clinical outcome was assessed by the Economic/Functional Outcome Scale.

RESULTS

Of the 321 patients, 308 were followed postoperatively (average 6.7 years) and 297 (96%) fused. Fusion rates were lower for patients with substance abuse (89%, P = 0.007). Clinical outcomes in 87% of patients were excellent (52%) or good (35%). Economic/Functional Outcome Scale scores after initial allo-PLIF on average increased 5.2 points. Successful fusion correlated with nearly a 2-point gain in outcome score (P = 0.001). A positive association between a patient characteristic and outcome was observed only with age 65 years and greater, whereas negative associations in clinical outcomes were observed with mental illness, substance abuse, heavy stress to the low back, or industrial injuries. The total complication rate was 7%.

CONCLUSIONS

With 3 decades of follow-up, we found that successful clinical outcomes are highly correlated with solid fusion using only allogeneic iliac bone.

Factors Associated with Adverse Events in Inpatient Elective Spine, Knee, and Hip Orthopaedic Surgery

BACKGROUND

Orthopaedic procedures for degenerative musculoskeletal conditions (predominantly osteoarthritis and spinal stenosis) represent an increasing burden on the health-care system. These procedures are also associated with adverse event rates and related cost. The objective of this study was to identify risk factors for adverse events associated with orthopaedic surgeries as captured within a common clinical point-of-care system for documenting adverse events (Orthopaedic Surgical AdVerse Events Severity [OrthoSAVES] system).

METHODS

In-hospital adverse events were recorded at the point of care over a 2-year period for inpatient elective knee, hip, and spine orthopaedic procedures for degenerative musculoskeletal conditions. Multivariable logistic regression was employed to investigate the association between various factors (age, sex, surgical site, body mass index, surgical risk classification, operative duration, length of stay, and medical comorbidities) and the occurrence of adverse events.

RESULTS

The sample included 2,146 patients. The overall adverse event rate was 27% (571 of 2,146), and by surgical site, the rates were 29% (130 of 442) for spine; 27% (266 of 998) for knee; and 25% (175 of 706) for hip. The most common adverse events had a low severity grade, but spinal procedures demonstrated more adverse events with a severity grade of ≥3. Increasing age (odds ratio [OR] = 1.21, 95% confidence interval [CI] =1.05 to 1.41, per 15-year interval), male sex (OR = 1.43, 95% CI =1.16 to 1.77), increasing operative duration (OR = 1.13, 95% CI = 1.03 to 1.23, per 30-minute increase), length of stay (OR = 1.13, 95% CI = 1.10 to 1.17, per day), and undergoing revision surgery (OR = 2.23, 95% CI = 1.35 to 3.70) were independently associated with a greater likelihood of the occurrence of an adverse event. Spine surgery demonstrated decreased odds of an adverse event compared with knee surgery (OR = 0.38, 95% CI = 0.23 to 0.61) when operative duration and length of stay were taken into account.

CONCLUSIONS

On the basis of our adjusted analysis, we found increasing age, male sex, revision surgery, length of stay, and increasing operative duration to be common independent risk factors for an adverse event across the population studied. The first 3 risk factors are not modifiable. The association between increasing operative duration and the risk of an adverse event across all anatomical regions and surgical procedures is a unique finding. However, modification of procedural efficiency is multifactorial and warrants further investigation.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Minimally Invasive Microsurgical Resection of Primary, Intradural Spinal Tumors is Feasible and Safe: A Consecutive Series of 83 Patients

BACKGROUND

To date, the traditional approach to intraspinal tumors has been open laminectomy or laminoplasty followed by microsurgical tumor resection. Recently, however, minimally invasive approaches have been attempted by some.

OBJECTIVE

To investigate the feasibility and safety of minimally invasive surgery (MIS) for primary intradural spinal tumors.

METHODS

Medical charts of 83 consecutive patients treated with MIS for intradural spinal tumors were reviewed. Patients were followed up during the study year, 2015, by either routine history/physical examination or by telephone consultation, with a focus on tumor status and surgery-related complications.

RESULTS

Mean age at surgery was 53.7 yr and 52% were female. There were 49 schwannomas, 18 meningeomas, 10 ependymomas, 2 hemangioblastomas, 1 neurofibroma, 1 paraganglioma, 1 epidermoid cyst, and 1 hemangiopericytoma. The surgical mortality was 0%. In 87% of cases, gross total resection was achieved. The complication rate was 11%, including 2 cerebrospinal fluid leakages, 1 asymptomatic pseudomeningocele, 2 superficial surgical site infections, 1 sinus vein thrombosis, and 4 cases of neurological deterioration. There were no postoperative hematomas, and no cases of deep vein thrombosis or pulmonary embolism. Ninety-three percent of patients were ambulatory and able to work at the time of follow-up.

CONCLUSION

This study both demonstrates that it is feasible and safe to remove select, primary intradural spinal tumors using MIS, and augments the previous literature in favor of MIS for these tumors.

Decision analysis to identify the ideal treatment for adult spinal deformity: What is the impact of complications on treatment outcomes?

Objective

The aim of this study was to analyze the impact of treatment complications on outcomes in adult spinal deformity (ASD) using a decision analysis (DA) model.

Methods

The study included 535 ASD patients (371 with non-surgical (NS) and 164 with surgical (S) treatment) from an international multicentre database of ASD patients. DA was structured in two main steps; 1) Baseline analysis (Assessing the probabilities of outcomes, Assessing the values of preference -utilities-, Combining information on probability and utility and assigning the quality adjusted life expectancy (QALE) for each treatment) and 2) Sensitivity analysis. Complications were analyzed as life threatening (LT) and nonlife threatening (NLT) and their probabilities were calculated from the database as well as a thorough literature review. Outcomes were analyzed as improvement, no change and deterioration. Death/complete paralysis was considered as a separate category.

Results

All 535 patients were analyzed in regard to complications. Overall, there were 78 NLT and 12 LT complications and 3 death/paralysis. Surgical treatment offered significantly higher chances of clinical improvement but also was significantly more prone to complications (31.7% vs. 11.1%, p < 0.001).

Conclusion

Surgical treatment of ASD is more likely to cause complications compared to NS treatment. On the other hand, surgery has been shown to provide a higher likelihood of improvement in HRQoL scores. So, the decision on the type of treatment in ASD needs to take both chances of improvement and burden associated with S or NS treatments and better be arrived by the active participation of patients and physicians equipped with the present information.

Level of evidence

Level II, Decision analysis.

Spinal Cord Stimulation in Failed Back Surgery Syndrome: Review of Clinical Use, Quality of Life and Cost-Effectiveness

Failed back surgery syndrome (FBSS) is complex and recurrent chronic pain after spinal surgery. Several important patient and surgery related risk factors play roles in development of FBSS. Inadequate selection of the candidates for the spinal surgeries is one of the most crucial causes. The guidelines suggest that conservative management featuring pharmacologic approaches and rehabilitation should be introduced first. For therapy-refractory FBSS, spinal cord stimulation (SCS) is recommended in selected patients. Treatment efficacy for FBSS has increased over the years with the majority of patients experiencing pain relief and reduced medicinal load. Improved quality of life can also be achieved using SCS. Cost-effectiveness of SCS still remains unclear. However evidence for SCS role in FBSS is controversial, SCS can be beneficial for carefully classified patients.

An assessment of data and methodology of online surgeon scorecards

OBJECTIVE Recently, 2 surgeon rating websites (Consumers' Checkbook and ProPublica) were published to allow the public to compare surgeons through identifying surgeon volume and complication rates. Among neurosurgeons and orthopedic surgeons, only cervical and lumbar spine, hip, and knee procedures were included in this assessment. METHODS The authors examined the methodology of each website to assess potential sources of inaccuracy. Each online tool was queried for reports on neurosurgeons specializing in spine surgery and orthopedic surgeons specializing in spine, hip, or knee surgery. Surgeons were chosen from top-ranked hospitals in the US, as recorded by a national consumer publication ranking system, within the fields of neurosurgery and orthopedic surgery. The results were compared for accuracy and surgeon representation, and the results of the 2 websites were also compared. RESULTS The methodology of each site was found to have opportunities for bias and limited risk adjustment. The end points assessed by each site were actually not complications, but proxies of complication occurrence. A search of 510 surgeons (401 orthopedic surgeons [79%] and 109 neurosurgeons [21%]) showed that only 28% and 56% of surgeons had data represented on Consumers' Checkbook and ProPublica, respectively. There was a significantly higher chance of finding surgeon data on ProPublica (p < 0.001). Of the surgeons from top-ranked programs with data available, 17% were quoted to have high complication rates, 13% with lower volume than other surgeons, and 79% had a 3-star out of 5-star rating. There was no significant correlation found between the number of stars a surgeon received on Consumers' Checkbook and his or her adjusted complication rate on ProPublica. CONCLUSIONS Both the Consumers' Checkbook and ProPublica websites have significant methodological issues. Neither site assessed complication occurrence, but rather readmissions or prolonged length of stay. Risk adjustment was limited or nonexistent. A substantial number of neurosurgeons and orthopedic surgeons from top-ranked hospitals have no ratings on either site, or have data that suggests they are low-volume surgeons or have higher complication rates. Consumers' Checkbook and ProPublica produced different results with little correlation between the 2 websites in how surgeons were graded. Given the significant methodological issues, incomplete data, and lack of appropriate risk stratification of patients, the featured websites may provide erroneous information to the public.

A scoring system to predict postoperative medical complications in high-risk patients undergoing elective thoracic and lumbar arthrodesis

BACKGROUND CONTEXT

Various surgical factors affect the incidence of postoperative medical complications following elective spinal arthrodesis. Because of the inter-relatedness of these factors, it is difficult for clinicians to accurately risk-stratify individual patients.

PURPOSE

Our goal was to develop a scoring system that predicts the rate of major medical complications in patients with significant preoperative medical comorbidities, as a function of the four perioperative parameters that are most closely associated with the invasiveness of the surgical intervention.

STUDY DESIGN/SETTING

This study used level 2, Prognostic Retrospective Study.

PATIENT SAMPLE

The patient sample consisted of 281 patients with American Society of Anesthesiologists (ASA) scores of 3-4 who underwent elective thoracic, lumbar, or thoracolumbar fusion surgeries from 2007 to 2011.

OUTCOME MEASURES

Physiologic risk factors, number of levels fused, complications, operative time, intraoperative fluids, and estimate blood loss were the outcome measures of this study.

METHODS

Risk factors were recorded, and patients who suffered major medical complications within the 30-day postoperative period were identified. We used chi-square tests to identify factors that affect the medical complication rate. These factors were ranked and scored by quartiles. The quartile scores were combined to form a single composite score. We determined the major medical complication rate for each composite score, and divided the cohort into quartiles again based on score. A Pearson linear regression analysis was used to compare the incidence of complications to the score.

RESULTS

The number of fused levels, operative time, volume of intraoperative fluids, and estimated blood loss influenced the complication rate of patients with ASA scores of 3-4. The quartile ranking of each of the four predictive factors was added, and the sum became the composite score. This score predicted the complication rate in a linear fashion ranging from 7.6% for the lowest risk group to 34.7% for the highest group (r=0.998, p<.001).

CONCLUSIONS

Taken together, the four factors, though not independent of one another, proved to be strongly predictive of the major medical complication rate. This score can be used to guide medical management of thoracic and lumbar spinal arthrodesis patients with preexisting medical comorbidities.

Predicting Occurrence of Spine Surgery Complications Using "Big Data" Modeling of an Administrative Claims Database

BACKGROUND

Postoperative metrics are increasingly important in determining standards of quality for physicians and hospitals. Although complications following spinal surgery have been described, procedural and patient variables have yet to be incorporated into a predictive model of adverse-event occurrence. We sought to develop a predictive model of complication occurrence after spine surgery.

METHODS

We used longitudinal prospective data from a national claims database and developed a predictive model incorporating complication type and frequency of occurrence following spine surgery procedures. We structured our model to assess the impact of features such as preoperative diagnosis, patient comorbidities, location in the spine, anterior versus posterior approach, whether fusion had been performed, whether instrumentation had been used, number of levels, and use of bone morphogenetic protein (BMP). We assessed a variety of adverse events. Prediction models were built using logistic regression with additive main effects and logistic regression with main effects as well as all 2 and 3-factor interactions. Least absolute shrinkage and selection operator (LASSO) regularization was used to select features. Competing approaches included boosted additive trees and the classification and regression trees (CART) algorithm. The final prediction performance was evaluated by estimating the area under a receiver operating characteristic curve (AUC) as predictions were applied to independent validation data and compared with the Charlson comorbidity score.

RESULTS

The model was developed from 279,135 records of patients with a minimum duration of follow-up of 30 days. Preliminary assessment showed an adverse-event rate of 13.95%, well within norms reported in the literature. We used the first 80% of the records for training (to predict adverse events) and the remaining 20% of the records for validation. There was remarkable similarity among methods, with an AUC of 0.70 for predicting the occurrence of adverse events. The AUC using the Charlson comorbidity score was 0.61. The described model was more accurate than Charlson scoring (p < 0.01).

CONCLUSIONS

We present a modeling effort based on administrative claims data that predicts the occurrence of complications after spine surgery.

CLINICAL RELEVANCE

We believe that the development of a predictive modeling tool illustrating the risk of complication occurrence after spine surgery will aid in patient counseling and improve the accuracy of risk modeling strategies.

Decision-making in the treatment of adult spinal deformity

Adult spinal deformity (ASD) is a very diverse condition that affects the quality of life of the involved individuals deeply. There is an ongoing discussion as to whether treatment should be surgical (which is potentially dangerous) or non-surgical.In addition to a systematic review of literature on the surgical treatment of ASD with special emphasis on complications, a decision-analysis was performed using the patient information within a European multi-centric database of ASD.The probabilities of improvement and complications as well as associated disease burden (utility) were calculated at the baseline and at first-year follow-up.Decision-analysis suggests that the chances of clinical improvement are significantly higher with surgical treatment. Though surgical treatment is significantly more prone to complications, the likelihood of improvement remains higher than that offered by non-surgical treatment.Surgical treatment of ASD appears to be associated with a higher likelihood of clinical improvement. Future work needs to focus on refining the criteria for appropriate patient selection and decreasing the incidence of complications. Cite this article: Acaroglu E, European Spine Study Group. Decision-making in the treatment of adult spinal deformity. EFORT Open Rev 2016;1:167-176. DOI: 10.1302/2058-5241.1.000013.

Diagnosis and neurologic status as predictors of surgical site infection in primary cervical spinal surgery

BACKGROUND CONTEXT

Surgical site infection (SSI) incidence after cervical spinal surgery ranges from 0.1% to 17%. Although the general risk factors for SSI have been discussed, the relationship of neurologic status and trauma to SSI has not been explicitly explored.

PURPOSE

This study aimed to study associated risk factors and to report the incidence of SSI in patients who have undergone cervical spinal surgery with the following four preoperative diagnoses: (1) degenerative disease with no myelopathy (MP), (2) degenerative disease with MP, (3) traumatic cervical injury without spinal cord injury (SCI), (4) traumatic cervical injury with SCI. We hypothesize that SSI incidence would increase from Group (1) to Group (4).

STUDY DESIGN

Retrospective database analysis was carried out.

PATIENTS SAMPLE

We used International Classification of Diseases codes to identify the four groups of patients in the U.S. Nationwide Inpatient Sample (NIS) from the years 2000 to 2011. We complemented this study with a similar search in our institutional database (ID) from the years 2000 to 2013. Patients with concomitant congenital deformity, infection, inflammatory disease, and neoplasia were excluded, as were revision surgeries.

OUTCOME MEASURES

The primary outcome studied was the occurrence of SSI. Statistical analyses included bivariate comparisons and chi-square distribution of demographic data and multivariable regression for demographic, surgical, and outcome variables.

RESULTS

A total of 1,247,281 and 5,540 patients met inclusion criteria in the NIS database and the ID, respectively. Overall SSI incidence was 0.73% (NIS) versus 1.75% (ID). Surgical site infection incidence increased steadily from 0.52% in Group (1) to 1.97% in Group (4) in the NIS data and from 0.88% to 5.54% in the ID. Differences between diagnostic groups and cohorts reached statistical significance. Surgical site infection was predicted significantly by status (odds ratio [OR] 1.69, p<.0001) and trauma (OR 1.30, p=.0003) in the NIS data. Other significant predictors included the following: approach, number of levels fused, female gender, black race, medium size hospital, rural hospital, large hospital, western US hospital and Medicare coverage. In the ID, only trauma (OR 2.11, p=.03) reached significance when accounting for comorbidities.

CONCLUSIONS

Both primary diagnosis (trauma vs. degenerative) and neurologic status (MP or SCI) were found to be strong and independent predictors of SSI in cervical spine surgery.

Effect of complications within 90 days on patient-reported outcomes 3 months and 12 months following elective surgery for lumbar degenerative disease

OBJECT

There is a paradigm shift toward rewarding providers for quality rather than volume. Complications appear to occur at a fairly consistent frequency in large aggregate data sets. Understanding how complications affect long-term patient-reported outcomes (PROs) following degenerative lumbar surgery is vital. The authors hypothesized that 90-day complications would adversely affect long-term PROs.

METHODS

Nine hundred six consecutive patients undergoing elective surgery for degenerative lumbar disease over a period of 4 years were enrolled into a prospective longitudinal registry. The following PROs were recorded at baseline and 12-month follow-up: Oswestry Disability Index (ODI) score, numeric rating scales for back and leg pain, quality of life (EQ-5D scores), general physical and mental health (SF-12 Physical Component Summary [PCS] and Mental Component Summary [MCS] scores) and responses to the North American Spine Society (NASS) satisfaction questionnaire. Previously published minimum clinically important difference (MCID) threshold were used to define meaningful improvement. Complications were divided into major (surgicalsite infection, hardware failure, new neurological deficit, pulmonary embolism, hematoma and myocardial infarction) and minor (urinary tract infection, pneumonia, and deep venous thrombosis).

RESULTS

Complications developed within 90 days of surgery in 13% (118) of the patients (major in 12% [108] and minor in 8% [68]). The mean improvement in ODI scores, EQ-5D scores, SF-12 PCS scores, and satisfaction at 3 months after surgery was significantly less in the patients with complications than in those who did not have major complications (ODI: 13.5 ± 21.2 vs 21.7 ± 19, < 0.0001; EQ-5D: 0.17 ± 0.25 vs 0.23 ± 0.23, p = 0.04; SF-12 PCS: 8.6 ± 13.3 vs 13.0 ± 11.9, 0.001; and satisfaction: 76% vs 90%, p = 0.002). At 12 months after surgery, the patients with major complications had higher ODI scores than those without complications (29.1 ± 17.7 vs 25.3 ± 18.3, p = 0.02). However, there was no difference in the change scores in ODI and absolute scores across all other PROs between the 2 groups. In multivariable linear regression analysis, after controlling for an array of preoperative variables, the occurrence of a major complication was not associated with worsening ODI scores 12 months after surgery. There was no difference in the percentage of patients achieving the MCID for disability (66% vs 64%), back pain (55% vs 56%), leg pain (62% vs 59%), or quality of life (19% vs 14%) or in patient satisfaction rates (82% vs 80%) between those without and with major complications.

CONCLUSIONS

Major complications within 90 days following lumbar spine surgery have significant impact on the short-term PROs. Patients with complications, however, do eventually achieve clinically meaningful outcomes and report satisfaction equivalent to those without major complications. This information allows a physician to counsel patients on the fact that a complication creates frustration, cost, and inconvenience; however, it does not appear to adversely affect clinically meaningful long-term outcomes and satisfaction.

Does intraoperative neurophysiologic monitoring matter in noncomplex spine surgeries?

Objectives:

To determine associations between intraoperative neurophysiologic monitoring (IOM) for spinal decompressions and simple fusions with neurologic complications, length of stay, and hospitalization charges.

Methods:

Adult discharges in the Nationwide/National Inpatient Sample (NIS) (2007–2012) with spinal decompressions and simple spinal fusions were included. Revision surgeries, instrumentations, complicated approaches, and tumor- and trauma-related surgeries were excluded. Extracted data included patient demographics, medical comorbidities, primary spinal surgery type, and hospital characteristics. Bivariate and multiple regression analyses using NIS survey design variables correlated IOM use with neurologic complications, hospital charges, and length of stay.

Results:

IOM was reported in 4.9% of an estimated 1.1 million discharges in the weighted sample. Discharges reporting IOM were more often privately insured (61% vs 57%, p < 0.001) and had slightly more comorbidities (25% vs 24% with 3+ comorbidities, p = 0.01). Spinal fusions more often reported IOM than decompressions. The IOM group had fewer neurologic complications (0.8% vs 1.4% of controls) with no difference in length of stay (3.0 days for each group), but increased hospital charges (39% greater). Multiple regression adjustment showed significant associations of IOM with fewer neurologic complications (odds ratio 0.60, 95% confidence interval [CI] 0.47, 0.76, p < 0.001), while the estimated percentage of hospital charges was sizably diminished from the unadjusted analysis (IOM effect +9%, 95% CI +4%, +13%, p < 0.001), and length of stay was reduced (IOM effect −0.26 days, 95% CI −0.42, −0.11, p < 0.001).

Conclusions:

IOM was associated with better clinical outcomes and some increased hospital charges among discharges of simple spinal fusions and laminectomies in a large, multiyear, nationally representative dataset.

Improved capture of adverse events after spinal surgery procedures with a longitudinal administrative database

OBJECT

The significant medical and economic tolls of spinal disorders, increasing volume of spine surgeries, and focus on quality metrics have made it imperative to understand postoperative complications. This study demonstrates the utility of a longitudinal administrative database for capturing overall and procedure-specific complication rates after various spine surgery procedures.

METHODS

The Thomson Reuters MarketScan Commercial Claims and Encounters and the Medicare Supplemental and Coordination of Benefits database was used to conduct a retrospective analysis of longitudinal administrative data from a sample of approximately 189,000 patients. Overall and procedure-specific complication rates at 5 time points ranging from immediately postoperatively (index) to 30 days postoperatively were computed.

RESULTS

The results indicated that the frequency of individual complication types increased at different rates. The overall complication rate including all spine surgeries was 13.6% at the index time point and increased to 22.8% at 30 days postoperatively. The frequencies of wound dehiscence, infection, and other wound complications exhibited large increases between 10 and 20 days postoperatively, while complication rates for new chronic pain, delirium, and dysrhythmia increased more gradually over the 30-day period studied. When specific surgical procedures were considered, 30-day complication rates ranged from 8.6% in single-level anterior cervical fusions to 27.3% in multilevel combined anterior and posterior lumbar spine fusions.

CONCLUSIONS

This study demonstrates the usefulness of a longitudinal administrative database in assessing postoperative complication rates after spine surgery. Use of this database gave results that were comparable to those in prospective studies and superior to those obtained with nonlongitudinal administrative databases. Longitudinal administrative data may improve the understanding of overall and procedure-specific complication rates after spine surgery.

Identification of complications that have a significant effect on length of stay after spine surgery and predictive value of 90-day readmission rate

OBJECT

Complications after spine surgery have an impact on overall outcome and health care expenditures. The increased cost of complications is due in part to associated prolonged hospital stays. The authors propose that certain complications have a greater impact on length of stay (LOS) than others and that those complications should be the focus of future targeted prevention efforts. They conducted a retrospective analysis of a prospectively maintained database to identify complications with the greatest impact on LOS as well as the predictive value of these complications with respect to 90-day readmission rates.

METHODS

Data on 249 patients undergoing spine surgery at Thomas Jefferson University from May to December 2008 were collected by a study auditor. Any complications occurring within 30 days of surgery were recorded as was overall LOS for each patient. Stepwise regression analysis was performed to determine whether specific complications had a statistically significant effect on LOS. For correlation, all readmissions within 90 days were recorded and organized by complication for comparison with those complications affecting LOS.

RESULTS

The mean LOS for patients without postoperative complications was 6.9 days. Patients who developed pulmonary complications had an associated increase in LOS of 11.1 days (p < 0.005). The development of a urinary tract infection (UTI) was associated with an increase in LOS of 3.4 days (p = 0.002). A new neurological deficit was associated with an increase in LOS of 8.2 days (p = 0.004). Complications requiring return to the operating room (OR) showed a trend toward an increase in LOS of 4.7 days (p = 0.09), as did deep wound infections (3.3 days, p = 0.08). The most common reason for readmission was for wound drainage (n = 21; surgical drainage was required in 10 [4.01%] of these 21 cases). The most common diagnoses for readmission, in decreasing order of incidence, were categorized as hardware malpositioning (n = 4), fever (n = 4), pulmonary (n = 2), UTI (n = 2), and neurological deficit (n = 1). Complications affecting LOS were not found to be predictive of readmission (p = 0.029).

CONCLUSIONS

Postoperative complications in patients who have undergone spine surgery are not uncommon and are associated with prolonged hospital stays. In the current cohort, the occurrence of pulmonary complications, UTI, and new neurological deficit had the greatest effect on overall LOS. Further study is required to determine the causative factors affecting readmission. These specific complications may be high-yield targets for cost reduction and/or prevention efforts.

Outpatient Cervical and Lumbar Spine Surgery is Feasible and Safe

BACKGROUND:

There is an increasing demand for surgery of degenerative spinal disease. Limited healthcare resources draw attention to the need for cost-effective treatments. Outpatient surgery, when safe and feasible, is more cost effective than inpatient surgery.

OBJECTIVE:

To study types and rates of complications after outpatient lumbar and cervical spine decompressions.

METHODS:

Complications were recorded prospectively in 1449 (1073 lumbar, 376 cervical) outpatients undergoing microsurgical decompression for degenerative spinal disease at the private Oslofjord Clinic from 2008 to 2013.

RESULTS:

Surgical mortality was 0%. A total of 51 (3.5%) minor and major complications were recorded in 51 patients. Three (0.2%) patients had to be admitted to a hospital the day of surgery. Twenty-two (1.5%) patients were admitted to a hospital within 3 months due to surgery-related events. The encountered complications were postoperative hematoma (0.6%), neurological deterioration (0.3%), deep wound infection (0.9%), dural lesions with cerebrospinal fluid leakage (1.0%), persistent dysphagia (0.1%), persistent hoarseness (0.1%), and severe pain/headache (0.4%). All of the life-threatening hematomas were detected within 6 and 3 hours after cervical and lumbar surgery, respectively.

CONCLUSION:

This series of 1449 consecutive outpatient microsurgical spine decompressions adds to the growing literature in favor of outpatient spinal surgery in properly selected patients. In our study, 99.8% of the patients were successfully discharged either to their homes or to a hotel on the day of surgery. The overall complication rate was 3.5%, surgical mortality was 0%, and only 1.5% had to be admitted to a hospital within 3 months after surgery.

Medical errors in neurosurgery

Background:

Medical errors cause nearly 100,000 deaths per year and cost billions of dollars annually. In order to rationally develop and institute programs to mitigate errors, the relative frequency and costs of different errors must be documented. This analysis will permit the judicious allocation of scarce healthcare resources to address the most costly errors as they are identified.

Methods:

Here, we provide a systematic review of the neurosurgical literature describing medical errors at the departmental level. Eligible articles were identified from the PubMed database, and restricted to reports of recognizable errors across neurosurgical practices. We limited this analysis to cross-sectional studies of errors in order to better match systems-level concerns, rather than reviewing the literature for individually selected errors like wrong-sided or wrong-level surgery.

Results:

Only a small number of articles met these criteria, highlighting the paucity of data on this topic. From these studies, errors were documented in anywhere from 12% to 88.7% of cases. These errors had many sources, of which only 23.7-27.8% were technical, related to the execution of the surgery itself, highlighting the importance of systems-level approaches to protecting patients and reducing errors.

Conclusions:

Overall, the magnitude of medical errors in neurosurgery and the lack of focused research emphasize the need for prospective categorization of morbidity with judicious attribution. Ultimately, we must raise awareness of the impact of medical errors in neurosurgery, reduce the occurrence of medical errors, and mitigate their detrimental effects.

A predictive model of complications after spine surgery: the National Surgical Quality Improvement Program (NSQIP) 2005-2010

BACKGROUND CONTEXT

There is increasing scrutiny by several regulatory bodies regarding the complications of spine surgery. Precise delineation of the risks contributing to those complications remains a topic of debate.

PURPOSE

We attempted to create a predictive model of complications in patients undergoing spine surgery.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

A total of 13,660 patients registered in the American College of Surgeons National Quality Improvement Project (NSQIP) database.

OUTCOME MEASURES

Thirty-day postoperative risks of stroke, myocardial infarction, death, infection, urinary tract infection (UTI), deep vein thrombosis (DVT), pulmonary embolism (PE), and return to the operating room.

METHODS

We performed a retrospective cohort study involving patients who underwent spine surgery between 2005 and 2010 and were registered in NSQIP. A model for outcome prediction based on individual patient characteristics was developed.

RESULTS

Of the 13,660 patients, 2,719 underwent anterior approaches (19.9%), 565 corpectomies (4.1%), and 1,757 fusions (12.9%). The respective 30-day postoperative risks were 0.05% for stroke, 0.2% for MI, 0.25% for death, 0.3% for infection, 1.37% for UTI, 0.6% for DVT, 0.29% for PE, and 3.15% for return to the operating room. Multivariate analysis demonstrated that increasing age, more extensive operations (fusion, corpectomy), medical deconditioning (weight loss, dialysis, peripheral vascular disease, coronary artery disease, chronic obstructive pulmonary disease, diabetes), increasing body mass index, non-independent mobilization (preoperative neurologic deficit), and bleeding disorders were independently associated with a more than 3 days' length of stay. A validated model for outcome prediction based on individual patient characteristics was developed. The accuracy of the model was estimated by the area under the receiver operating characteristic curve, which was 0.95, 0.82, 0.87, 0.75, 0.74, 0.78, 0.76, 0.74, and 0.65 for postoperative risk of stroke, myocardial infarction, death, infection, DVT, PE, UTI, length of stay of 3 days or longer, and return to the operating room, respectively.

CONCLUSIONS

Our model can provide individualized estimates of the risks of postoperative complications based on preoperative conditions, and can potentially be used as an adjunct in decision-making for spine surgery.

Impact of bone morphogenetic proteins on frequency of revision surgery, use of autograft bone, and total hospital charges in surgery for lumbar degenerative disease: review of the Nationwide Inpatient Sample from 2002 to 2008

BACKGROUND CONTEXT

Bone morphogenetic proteins (BMPs) were developed with the goal of improving clinical outcomes through the promotion of bony healing and reducing morbidity from iliac crest bone graft harvest.

PURPOSE

To complete a population-based assessment of the impact of BMP on use of autograft, rates of operative treatment for lumbar pseudoarthrosis, and hospital charges.

STUDY DESIGN

Nationwide Inpatient Sample (NIS) retrospective cohort assessment of 46,452 patients from 2002 to 2008.

PATIENT SAMPLE

All patients who underwent lumbar arthrodesis procedures for degenerative spinal disease.

OUTCOME MEASURES

Use of BMP, revision surgery status as a percentage of total procedures, and autograft harvest in lumbar fusion procedures completed for degenerative diagnoses.

METHODS

Demographic and geographic/practice data, hospital charges, and length of stay of all NIS patients with thoracolumbar and lumbosacral procedure codes for degenerative spinal diagnoses were recorded. Codes for autograft harvest, use of BMP, and revision surgery were included in multivariable regression analysis.

RESULTS

The assessment found 46,452 patients from 2002 to 2008 undergoing thoracolumbar or lumbar arthrodesis procedures for degenerative disease. Assuming a representative sample, this cohort models more than 200,000 US patients. There was steady growth in lumbar spine fusion and in the use of BMP. The use of BMP increased from 2002 to 2008 (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.48-1.52). Revision procedures decreased over the study period (OR, 0.94; 95% CI, 0.91-0.96). The use of autograft decreased substantially after introduction of BMP but then returned to baseline levels; there was no net change in autograft use from 2002 to 2008. The use of BMP correlated with significant increases in hospital charges ($13,362.39; standard deviation ± 596.28, p<.00001). The use of BMP in degenerative thoracolumbar procedures potentially added more than $900 million to hospital charges from 2002 to 2008.

CONCLUSIONS

There was an overall decrease in rates of revision fusion procedures from 2002 to 2008. Introduction of BMP did not correlate with decrease in use of autograft bone harvest. Use of BMP correlated with substantial increase in hospital charges. The small decrease in revision surgeries recorded, combined with lack of significant change in autograft harvest rates, may question the financial justification for the use of BMP.

Calculating risks: the power and pitfalls of registry data

Schoenfeld AJ, Carey PA, Cleveland AW III, et al. Patient factors, comorbidities, and surgical characteristics that increase mortality and complication risk after spinal arthrodesis: a prognostic study based on 5,887 patients. Spine J 2013;13:1171-79 (in this issue).

Clinical outcomes of epidural neuroplasty for cervical disc herniation

Cervical disc herniation is a common disorder characterized by neck pain radiating to the arm and fingers as determined by the affected dermatome. This condition has a favorable prognosis, but pain can have a serious detrimental impact on daily activities. Epidural neuroplasty has been applied as a treatment option for cervical disc herniation; however, no study has addressed the clinical outcomes. This retrospective study evaluated the clinical outcomes of epidural neuroplasty on 128 patients for the treatment of cervical disc herniation. To measure pain-related disabilities over time, the changes of pain scores in neck and arm were evaluated using a numerical rating scale (NRS) and the neck disability index (NDI). Compared with preprocedural values, the pain NRS of neck and arm demonstrated significant improvement at day 1, and 1, 3, 6, and 12 months after the procedure (P < 0.001). Likewise, the NDI was significantly reduced at 3, 6, and 12 months after the procedure (P < 0.001). There were no serious complications. Cervical epidural neuroplasty shows good clinical outcomes in the treatment of cervical disc herniation and can be considered a treatment modality for cervical disc herniation refractory to conservative treatment.

Measuring surgical outcomes in neurosurgery: implementation, analysis, and auditing a prospective series of more than 5000 procedures

OBJECT

Health care reform debate includes discussions regarding outcomes of surgical interventions. Yet quality of medical care, when judged as a health outcome, is difficult to define because of impediments affecting accuracy in data collection, analysis, and reporting. In this prospective study, the authors report the outcomes for neurosurgical treatment based on point-of-care interactions recorded in the electronic medical record (EMR).

METHODS

The authors' neurosurgery practice collected outcome data for 19 physicians and ancillary personnel using the EMR. Data were analyzed for 5361 consecutive surgical cases, either elective or emergency procedures, performed during 2009 at multiple hospitals, offices, and an ambulatory spine surgery center. Main outcomes included complications, length of stay (LOS), and discharge disposition for all patients and for certain frequently performed procedures. Physicians, nurses, and other medical staff used validated scales to record the hospital LOS, complications, disposition at discharge, and return to work.

RESULTS

Of the 5361 surgical procedures performed, two-thirds were spinal procedures and one-third were cranial procedures. Organization-wide compliance with reporting rates of major complications improved throughout the year, from 80.7% in the first quarter to 90.3% in the fourth quarter. Auditing showed that rates of unreported complications decreased from 11% in the first quarter to 4% in the fourth quarter. Complication data were available for 4593 procedures (85.7%); of these, no complications were reported in 4367 (95.1%). Discharge dispositions reported were home in 86.2%, rehabilitation center in 8.9%, and nursing home in 2.5%. Major complications included culture-proven infection in 0.61%, CSF leak in 0.89%, reoperation within the same hospitalization in 0.38%, and new neurological deficits in 0.77%. For the commonly performed procedures, the median hospital LOS was 3 days for craniotomy for aneurysm or intraaxial tumor and less than 1 day for angiogram, anterior cervical discectomy with fusion, or lumbar discectomy.

CONCLUSIONS

With prospectively collected outcome data for more than 5000 surgeries, the authors achieved their primary end point of institution-wide compliance and data accuracy. Components of this process included staged implementation with physician pilot studies and oversight, nurse participation, point-of-service data capture, EMR form modification, data auditing, and confidential surgeon reports.

Perioperative risk factors related to lumbar spine fusion surgery in korean geriatric patients

Objective

Life expectancy for humans has increased dramatically and with this there has been a considerable increase in the number of patients suffering from lumbar spine disease. Symptomatic lumbar spinal disease should be treated, even in the elderly, and surgical procedures such as fusion surgery are needed for moderate to severe lumbar spinal disease. However, various perioperative complications are associated with fusion surgery. The aim of this study was to examine perioperative complications and assess risk factors associated with lumbar spinal fusion, focusing on geriatric patients at least 70 years of age in the Republic of Korea.

Methods

We retrospectively investigated 489 patients with various lumbar spinal diseases who underwent lumbar spinal fusion surgery between 2003 and 2007 at our institution. Three fusion procedures and the number of fused segments were analyzed in this study. Chronic diseases were also evaluated. Risk factors for complications and their association with age were analyzed.

Results

In this study, 74 patients experienced complications (15%). The rate of perioperative complications was significantly higher in patients 70 years of age or older than in other age groups (univariate analysis, p=0.001; multivariate analysis, p=0.004). However, perioperative complications were not significantly associated with the other factors tested (sex, comorbidities, operation procedures, fusion segments involved).

Conclusion

Increasing age was an important risk factor for perioperative complications in patients undergoing lumbar spinal fusion surgery whereas other factors were not significant. We recommend good clinical judgment and careful selection of geriatric patients undergoing lumbar spinal fusion surgery.

Patient comorbidity score predicting the incidence of perioperative complications: assessing the impact of comorbidities on complications in spine surgery

Object

Present attempts to control health care costs focus on reducing the incidence of complications and hospital-acquired conditions (HACs). One approach uses restriction or elimination of hospital payments for HACs. Present approaches assume that all HACs are created equal and that payment restrictions should be applied uniformly. Patient factors, and especially patient comorbidities, likely impact complication incidence. The relationship of patient comorbidities and complication incidence in spine surgery has not been prospectively reported.

Methods

The authors conducted a prospective assessment of complications in spine surgery during a 6-month period; an independent auditor and a validated definition of perioperative complications were used. Initial demographics captured relevant patient comorbidities. The authors constructed a model of relative risk assessment based on the presence of a variety of comorbidities. They examined the impact of specific comorbidities and the cumulative effect of multiple comorbidities on complication incidence.

Results

Two hundred forty-nine patients undergoing 259 procedures at a tertiary care facility were evaluated during the 6-month duration of the study. Eighty percent of the patients underwent fusion procedures. One hundred thirty patients (52.2%) experienced at least 1 complication, with major complications occurring in 21.4% and minor complications in 46.4% of the cohort. Major complications doubled the median duration of hospital stay, from 6 to 12 days in cervical spine patients and from 7 to 14 days in thoracolumbar spine patients. At least 1 comorbid condition was present in 86% of the patients. An increasing number of comorbidities strongly correlated with increased risk of major, minor, and any complications (p = 0.017, p < 0.0001, and p < 0.0001, respectively). Patient factors correlating with increased risk of specific complications included systemic malignancy and cardiac conditions other than hypertension.

Conclusions

Comorbidities significantly increase the risk of perioperative complications. An increasing number of comorbidities in an individual patient significantly increases the risk of a perioperative adverse event. Patient factors significantly impact the relative risk of HACs and perioperative complications.

Complications related to instrumentation in spine surgery: a prospective analysis

Object

Prospective examination of perioperative complications in spine surgery is limited in the literature. The authors prospectively collected data on patients who underwent spinal fusion at a tertiary care center and evaluated the effect of spinal fusion and comorbidities on perioperative complications.

Methods

Between May and December 2008 data were collected prospectively in 248 patients admitted to the authors' institution for spine surgery. The 202 patients undergoing spine surgery with instrumentation were further analyzed in this report. Perioperative complications occurring within the initial 30 days after surgery were included. All adverse occurrences, whether directly related to surgery, were included in the analysis.

Results

Overall, 114 (56.4%) of 202 patients experienced at least one perioperative complication. Instrumented fusions were associated with more minor complications (p = 0.001) and more overall complications (0.0024). Furthermore, in the thoracic and lumbar spine, complications increased based on the number of levels fused. Advanced patient age and certain comorbidities such as diabetes, cardiac disease, or a history of malignancy were also associated with an increased incidence of complications.

Conclusions

Using a prospective methodology with a broad definition of complications, the authors report a significantly higher perioperative incidence of complications than previously indicated after spinal fusion procedures. Given the increased application of instrumentation, especially for degenerative disease, a better estimate of clinically relevant surgical complications could aid spine surgeons and patients in an individualized complication index to facilitate a more thorough risk-benefit analysis prior to surgery.