Association Between Race and Short-Term Outcomes Across 3988 Consecutive Single-Level Spinal Fusions

BACKGROUND AND OBJECTIVES

Race has implications for access to medical care. However, the impact of race, after access to care has been attained, remains poorly understood. The objective of this study was to isolate the relationship between race and short-term outcomes across patients undergoing a single, common neurosurgical procedure.

METHODS

In this retrospective cohort study, 3988 consecutive patients undergoing single-level, posterior-only open lumbar fusion at a single, multihospital, academic medical center were enrolled over a 6-year period. Among them, 3406 patients self-identified as White, and 582 patients self-identified as Black. Outcome disparities between all White patients vs all Black patients were estimated using logistic regression. Subsequently, coarsened exact matching controlled for outcome-mitigating factors; White and Black patients were exact-matched 1:1 on key demographic and health characteristics (matched n = 1018). Primary outcomes included 30-day and 90-day hospital readmissions, emergency department (ED) visits, reoperations, mortality, discharge disposition, and intraoperative complication.

RESULTS

Before matching, Black patients experienced increased rate of nonhome discharge, readmissions, ED visits, and reoperations (all P < .001). After exact matching, Black patients were less likely to be discharged to home (odds ratio [OR] 2.68, P < .001) and had higher risk of 30-day and 90-day readmissions (OR 2.24, P < .001; OR 1.91, P < .001; respectively) and ED visits (OR 1.79, P = .017; OR 2.09, P < .001). Black patients did not experience greater risk of intraoperative complication (unintentional durotomy).

CONCLUSION

Between otherwise homogenous spinal fusion cohorts, Black patients experienced unfavorable short-term outcomes. These disparities were not explained by differences in intraoperative complications. Further investigation must characterize and mitigate institutional and societal factors that contribute to outcome disparities.

Effects of Augmented Reality on Thoracolumbar Pedicle Screw Instrumentation Across Different Levels of Surgical Experience

OBJECTIVE

Augmented reality (AR) is an emerging technology that may accelerate skill acquisition and improve accuracy of thoracolumbar pedicle screw placements. We aimed to quantify the relative assistance of AR compared with freehand (FH) pedicle screw accuracy across different surgical experience levels.

METHODS

A spine fellowship-trained and board-certified attending neurosurgeon, postgraduate year 4 neurosurgery resident, and second-year medical student placed 32 FH and 32 AR-assisted thoracolumbar pedicle screws in 3 cadavers. A cableless, voice-activated AR system was paired with a headset. Accuracy was assessed using χ2 analysis and the Gertzbein-Robbins scale. Angular error, distance error, and time per pedicle screw were collected and compared.

RESULTS

The attending neurosurgeon had 91.6% (11/12) clinically acceptable (Gertzbein-Robbins scale A or B) insertion in both FH and AR groups; the resident neurosurgeon had 100% (9/9) FH and AR in both cases; the medical student had 72.3% (8/11) FH accuracy and 81.8% (9/11) AR accuracy. The medical student displayed significantly lower ideal (Gertzbein-Robbins scale A) FH accuracy compared with the resident neurosurgeon (P = 0.017) and attending neurosurgeon (P = 0.005), but no difference when using AR. FH screw placement was faster by both the attending neurosurgeon (median 46 seconds vs. 94.5 seconds, P = 0.0047) and the neurosurgery resident neurosurgeon (median 144 seconds vs. 140 seconds, P = 0.05). Total clinically acceptable AR and FH accuracy was 90.6% (29/32) and 87.5% (28/32), respectively (P = 0.69).

CONCLUSIONS

AR screw placement allowed an inexperienced medical student to double their accuracy in 1 training session. With subsequent iterations, this promising technology could serve as an important tool for surgical training.

Determining Differences in Perioperative Functional Mobility Patterns in Lumbar Decompression Versus Fusion Patients Using Smartphone Activity Data

BACKGROUND AND OBJECTIVES

Smartphone activity data recorded through high-fidelity accelerometry can provide accurate postoperative assessments of patient mobility. The "big data" available through smartphones allows for advanced analyses, yielding insight into patient well-being. This study compared rate of change in functional activity data between lumbar fusion (LF) and lumbar decompression (LD) patients to determine preoperative and postoperative course differences.

METHODS

Twenty-three LF and 18 LD patients were retrospectively included. Activity data (steps per day) recorded in Apple Health, encompassing over 70 000 perioperative data points, was classified into 6 temporal epochs representing distinct functional states, including acute preoperative decline, immediate postoperative recovery, and postoperative decline. The daily rate of change of each patient's step counts was calculated for each perioperative epoch.

RESULTS

Patients undergoing LF demonstrated steeper preoperative declines than LD patients based on the first derivative of step count data (P = .045). In the surgical recovery phase, LF patients had slower recoveries (P = .041), and LF patients experienced steeper postoperative secondary declines than LD patients did (P = .010). The rate of change of steps per day demonstrated varying perioperative trajectories that were not explained by differences in age, comorbidities, or levels operated.

CONCLUSION

Patients undergoing LF and LD have distinct perioperative activity profiles characterized by the rate of change in the patient daily steps. Daily steps and their rate of change is thus a valuable metric in phenotyping patients and understanding their postsurgical outcomes. Prospective studies are needed to expand upon these data and establish causal links between preoperative patient mobility, patient characteristics, and postoperative functional outcomes.

Relationship Between Comorbidity Burden and Short-Term Outcomes Across 4680 Consecutive Spinal Fusions

OBJECTIVE

Preoperative management requires the identification and optimization of modifiable medical comorbidities, though few studies isolate comorbid status from related patient-level variables. This study evaluates Charlson Comorbidity Index (CCI)-an easily derived measure of aggregate medical comorbidity-to predict outcomes from spinal fusion surgery. Coarsened exact matching is employed to control for key patient characteristics and isolate CCI.

METHODS

We retrospectively assessed 4680 consecutive patients undergoing single-level, posterior-only lumbar fusion at a single academic center. Logistic regression evaluated the univariate relationship between CCI and patient outcomes. Coarsened exact matching generated exact demographic matches between patients with high comorbid status (CCI >6) or no medical comorbidities (matched n = 524). Patients were matched 1:1 on factors associated with surgical outcomes, and outcomes were compared between matched cohorts. Primary outcomes included surgical complications, discharge status, 30- and 90-day risk of readmission, emergency department (ED) visits, reoperation, and mortality.

RESULTS

Univariate regression of increasing CCI was significantly associated with non-home discharge, as well as 30- and 90-day readmission, ED visits, and mortality (all P < 0.05). Subsequent isolation of comorbidity between otherwise exact-matched cohorts found comorbid status did not affect readmissions, reoperations, or mortality; high CCI score was significantly associated with non-home discharge (OR = 2.50, P < 0.001) and 30-day (OR = 2.44, P = 0.02) and 90-day (OR = 2.29, P = 0.008) ED evaluation.

CONCLUSIONS

Comorbidity, measured by CCI, did not increase the risk of readmission, reoperation, or mortality. Single-level, posterior lumbar fusions may be safe in appropriately selected patients regardless of comorbid status. Future studies should determine whether CCI can guide discharge planning and postoperative optimization.

Large Language Model-Based Neurosurgical Evaluation Matrix: A Novel Scoring Criteria to Assess the Efficacy of ChatGPT as an Educational Tool for Neurosurgery Board Preparation

INTRODUCTION

Technological advancements are reshaping medical education, with digital tools becoming essential in all levels of training. Amidst this transformation, the study explores the potential of ChatGPT, an artificial intelligence model by OpenAI, in enhancing neurosurgical board education. The focus extends beyond technology adoption to its effective utilization, with ChatGPT's proficiency evaluated against practice questions from the Primary Neurosurgery Written Board Exam.

METHODS

Using the Congress of Neurologic Surgeons (CNS) Self-Assessment Neurosurgery (SANS) Exam Board Review Prep questions, we conducted 3 rounds of analysis with ChatGPT. We developed a novel ChatGPT Neurosurgical Evaluation Matrix (CNEM) to assess the output quality, accuracy, concordance, and clarity of ChatGPT's answers.

RESULTS

ChatGPT achieved spot-on accuracy for 66.7% of prompted questions, 59.4% of unprompted questions, and 63.9% of unprompted questions with a leading phrase. Stratified by topic, accuracy ranged from 50.0% (Vascular) to 78.8% (Neuropathology). In comparison to SANS explanations, ChatGPT output was considered better in 19.1% of questions, equal in 51.6%, and worse in 29.3%. Concordance analysis showed that 95.5% of unprompted ChatGPT outputs and 97.4% of unprompted outputs with a leading phrase were aligned.

CONCLUSIONS

Our study evaluated the performance of ChatGPT in neurosurgical board education by assessing its accuracy, clarity, and concordance. The findings highlight the potential and challenges of integrating AI technologies like ChatGPT into medical and neurosurgical board education. Further research is needed to refine these tools and optimize their performance for enhanced medical education and patient care.

Defining the minimal clinically important difference in smartphone-based mobility after spine surgery: correlation of survey questionnaire to mobility data

OBJECTIVE

Patient-reported outcome measures (PROMs) are the gold standard for assessing postoperative outcomes in spine surgery. However, PROMs are also limited by the inherent subjectivity of self-reported qualitative data. Recent literature has highlighted the utility of patient mobility data streamed from smartphone accelerometers as an objective measure of functional outcomes and complement to traditional PROMs. Still, for activity-based data to supplement existing PROMs, they must be validated against current metrics. In this study, the authors assessed the relationships and concordance between longitudinal smartphone-based mobility data and PROMs.

METHODS

Patients receiving laminectomy (n = 21) or fusion (n = 10) between 2017 and 2022 were retrospectively included. Activity data (steps-per-day count) recorded in the Apple Health mobile application over a 2-year perioperative window were extracted and subsequently normalized to allow for intersubject comparison. PROMS, including the visual analog scale (VAS), Patient Reported Outcome Measurement Information System Pain Interference (PROMIS-PI), Oswestry Disability Index (ODI), and EQ-5D, collected at the preoperative and 6-week postoperative visits were retrospectively extracted from the electronic medical record. Correlations between PROMs and patient mobility were assessed and compared between patients who did and those who did not achieve the established minimal clinically important difference (MCID) for each measure.

RESULTS

A total of 31 patients receiving laminectomy (n = 21) or fusion (n = 10) were included. Change between preoperative and 6-week postoperative VAS and PROMIS-PI scores demonstrated moderate (r = -0.46) and strong (r = -0.74) inverse correlations, respectively, with changes in normalized steps-per-day count. In cohorts of patients who achieved PROMIS-PI MCID postoperatively, indicating subjective improvement in pain, there was a 0.784 standard deviation increase in normalized steps per day, representing a 56.5% improvement (p = 0.027). Patients who did achieve the MCID of improvement in either PROMIS-PI or VAS after surgery were more likely to experience an earlier sustained improvement in physical activity commensurate to or greater than their preoperative baseline (p = 2.98 × 10-18) than non-MCID patients.

CONCLUSIONS

This study demonstrates a strong correlation between changes in mobility data extracted from patient smartphones and changes in PROMs following spine surgery. Further elucidating this relationship will allow for more robust supplementation of existing spine outcome measure tools with analyzed objective activity data.

Standardizing Lumbar Interbody Fusion Nomenclature

STUDY DESIGN

This article is a research methodology study.

OBJECTIVE

We summarize current ambiguities and inaccuracies regarding lumbar interbody fusion nomenclature and propose a standardized reporting method to improve the clarity of future research and communication among spine surgeons and researchers.

SUMMARY OF BACKGROUND DATA

Lumbar interbody fusion techniques have seen an impressive degree of refinement over recent years. This innovation has ushered in a plethora of naming conventions for these new surgical approaches. Many of the current trends in naming lumbar fusion techniques are, however, redundant and contradictory, creating unnecessary confusion in the field.

METHODS

Following an extensive literature review, we developed a 4-part naming convention that highlights the crucial features of lumbar fusion surgical procedures.

RESULTS

Current literature regarding lumbar fusions is rife with inconsistent usage and privatization of terminology that can inadvertently result in ambiguous operative vocabulary, potentially compromising the accuracy of future research. We propose a 4-part naming system that highlights crucial features of lumbar interbody fusions, including (1) intra-operative repositioning, (2) patient position, (3) surgical technique, and (4) orientation of the surgical corridor to the psoas muscle.

CONCLUSIONS

This study raises awareness of current inconsistencies in naming conventions and proposes a standardized system for improving the clarity of lumber interbody fusion terminology for the broader spine community.

LEVEL OF EVIDENCE

Level V.

A Prospective Cohort Study of Radiation Exposure to a Spine Surgeon's Exposed Body Parts During Utilization of Intraoperative Radiation-based Imaging

STUDY DESIGN

Prospective cohort study.

SUMMARY OF BACKGROUND DATA

C-arm fluoroscopy and O-arm navigation are vital tools in modern spine surgeries, but their repeated usage can endanger spine surgeons. Although a surgeon's chest and abdomen are protected by lead aprons, the eyes and extremities generally receive less protection.

OBJECTIVE

In this study, we compare differences in intraoperative radiation exposure across the protected and unprotected regions of a surgeon's body.

METHODS

Sixty-five consecutive spine surgeries were performed by a single spine-focused neurosurgeon over 9 months. Radiation exposure to the primary surgeon was measured through dosimeters worn over the lead apron, under the lead apron, on surgical loupes, and as a ring on the dominant hand. Differences were assessed with rigorous statistical testing and radiation exposure per surgical case was extrapolated.

RESULTS

During the study, the measured radiation exposure over the apron, 176 mrem, was significantly greater than that under the apron, 8 mrem (P = 0.0020), demonstrating a shielding protective effect. The surgeon's dominant hand was exposed to 329 mrem whereas the eyes were exposed to 152.5 mrem of radiation. Compared with the surgeon's protected abdominal area, the hands (P = 0.0002) and eyes (P = 0.0002) received significantly greater exposure. Calculated exposure per case was 2.8 mrem for the eyes and 5.1 mrem for the hands. It was determined that a spine-focused neurosurgeon operating 400 cases annually will incur a radiation exposure of 60,750 mrem to the hands and 33,900 mrem to the eyes over a 30-year career.

CONCLUSIONS

Our study found that spine surgeons encounter significantly more radiation exposure to the eyes and the extremities compared with protected body regions. Lifetime exposure exceeds the annual limits set by the International Commission on Radiologic Protection for the extremities (50,000 mrem/y) and the eyes (15,000 mrem/y), calling for increased awareness about the dangerous levels of radiation exposure that a spine surgeon incurs over one's career.

Characterizing and Improving Nomenclature for Reporting Lumbar Interbody Fusion Techniques

BACKGROUND

Lumbar interbody fusion (LIF) techniques have seen impressive innovation in recent years, leading to an expansion of the LIF lexicon.

OBJECTIVE

This study systematically analyzes LIF nomenclature in contemporary literature and proposes a standardized classification system for reporting LIF terminology.

METHODS

A search query was conducted through the PubMed database using "lumbar fusion OR lumbar interbody fusion". A total of 1,455 articles were identified, and 605 references to LIF were recorded. Following a systematic review of the terminology, we developed a LIF reporting guidelines that capture the existing LIF nomenclature while avoiding redundant or ambiguous terminology.

RESULTS

The most referenced anatomical approaches were transforaminal (43.0%), followed by posterior (25.0%), lateral (19.7%), and anterior (10.9%). Overall, there were 72 unique ways to describe LIF. Unique prefixes were recorded by approach (posterior: 26; lateral: 13; anterior: 3). 40 unique prefixes/suffixes overlapped in their usage. 'MI' (14.4%), 'MIS' (38.1%), and 'MISS' (0.6%) all referenced a minimally invasive approach. 'O' (12.5%), 'CO' (1.3%), and 'TO' (1.3%) all described open techniques. 'Endo' (0.6%), 'Endoscopic-assisted' (1.3%), and 'PE' (1.9%) all referenced endoscopic-assisted procedures.

CONCLUSION

The current lumbar interbody fusion nomenclature contains many unique LIF terms that were found to be inconsistently defined, redundant, or ambiguous. We propose the standardization of a 4-part naming system which highlights the crucial parts of lumbar interbody fusion: (1) intra-operative repositioning, (2) patient position, (3) anatomical approach, and (4) orientation of the surgical corridor to the psoas muscles.

Virtual and Augmented Reality in Spine Surgery: A Systematic Review

BACKGROUND

Augmented reality (AR) and virtual reality (VR) implementation in spinal surgery has expanded rapidly over the past decade. This systematic review summarizes the use of AR/VR technology in surgical education, preoperative planning, and intraoperative guidance.

METHODS

A search query for AR/VR technology in spine surgery was conducted through PubMed, Embase, and Scopus. After exclusions, 48 studies were included. Included studies were then grouped into relevant subsections. Categorization into subsections yielded 12 surgical training studies, 5 preoperative planning, 24 intraoperative usage, and 10 radiation exposure.

RESULTS

VR-assisted training significantly reduced penetration rates or increased accuracy rates compared to lecture-based groups in 5 studies. Preoperative VR planning significantly influenced surgical recommendations and reduced radiation exposure, operating time, and estimated blood loss. For 3 patient studies, AR-assisted pedicle screw placement accuracy ranged from 95.77% to 100% using the Gertzbein grading scale. Head-mounted display was the most common interface used intraoperatively followed by AR microscope and projector. AR/VR also had applications in tumor resection, vertebroplasty, bone biopsy, and rod bending. Four studies reported significantly reduced radiation exposure in AR group compared to fluoroscopy group.

CONCLUSIONS

AR/VR technologies have the potential to usher in a paradigm shift in spine surgery. However, the current evidence indicates there is still a need for 1) defined quality and technical requirements for AR/VR devices, 2) more intraoperative studies that explore usage outside of pedicle screw placement, and 3) technological advancements to overcome registration errors via the development of an automatic registration method.

Simultaneous Anterior Posterior Approach for Single-Position Lateral Lumbar Interbody Fusion with Robotic Assistance: Technical Guidelines and Early Outcomes

BACKGROUND

Lumbar lateral interbody fusion (LLIF) is traditionally performed in 2 stages: placing the interbody cage in the lateral decubitus position, then placing the percutaneous pedicle screw in the prone position. Performing interbody fusion and posterior fixation simultaneously could improve operative efficiency and clinical outcomes associated with longer operative times. We describe the operative steps and report clinical and radiographic outcomes associated with a simultaneous anterior and posterior approach (SAPA) for LLIF.

METHODS

Patients who underwent SAPA LLIF performed by a single surgeon over 1 year were retrospectively reviewed. Demographic, clinical, and radiographic data were analyzed, an operative guideline was created, and a learning curve was constructed using operative times.

RESULTS

SAPA LLIF was performed in 11 patients. Three patients experienced transient postoperative femoral nerve plexopathy with symptoms of ipsilateral hip flexion weakness and/or anterior thigh numbness; there were no other complications in the cohort. Radiographically, patients achieved significant increases in disc height (8.3 mm vs. 13.5 mm, P = 0.002) and foraminal height (20.2 mm vs. 25.3 mm, P = 0.0001). Patients showed significant improvements in Oswestry Disability Index (52 vs. 27.8, P = 0.002) and Patient-Reported Outcome Measurement Information System Physical Function (32.6 vs. 39, P = 0.048) and Pain Interference (64.9 vs. 59.6, P = 0.001) at 3 months. A downward trend in operative time was observed for 1-level SAPA LLIF.

CONCLUSIONS

SAPA LLIF is a safe approach for LLIF that results in favorable clinical outcomes. This technique can potentially improve operative efficiency further along the course of a surgeon's learning curve.

Methods and Impact for Using Federated Learning to Collaborate on Clinical Research

BACKGROUND

The development of accurate machine learning algorithms requires sufficient quantities of diverse data. This poses a challenge in health care because of the sensitive and siloed nature of biomedical information. Decentralized algorithms through federated learning (FL) avoid data aggregation by instead distributing algorithms to the data before centrally updating one global model.

OBJECTIVE

To establish a multicenter collaboration and assess the feasibility of using FL to train machine learning models for intracranial hemorrhage (ICH) detection without sharing data between sites.

METHODS

Five neurosurgery departments across the United States collaborated to establish a federated network and train a convolutional neural network to detect ICH on computed tomography scans. The global FL model was benchmarked against a standard, centrally trained model using a held-out data set and was compared against locally trained models using site data.

RESULTS

A federated network of practicing neurosurgeon scientists was successfully initiated to train a model for predicting ICH. The FL model achieved an area under the ROC curve of 0.9487 (95% CI 0.9471-0.9503) when predicting all subtypes of ICH compared with a benchmark (non-FL) area under the ROC curve of 0.9753 (95% CI 0.9742-0.9764), although performance varied by subtype. The FL model consistently achieved top three performance when validated on any site's data, suggesting improved generalizability. A qualitative survey described the experience of participants in the federated network.

CONCLUSION

This study demonstrates the feasibility of implementing a federated network for multi-institutional collaboration among clinicians and using FL to conduct machine learning research, thereby opening a new paradigm for neurosurgical collaboration.

Combined L5-S1 Anterior Lumbar Interbody Fusion and Multilevel Lateral Lumbar Interbody Fusion in a Single-Stage Lateral Decubitus Position Using Fluoroscopy-Based Instrument Tracking System

Anterior lumbar interbody fusion (ALIF), traditionally performed supine, allows for significant restoration of lumbar lordosis, disc height, and foraminal height in degenerative spine diseases; however, an iatrogenic injury to the viscera and the great vessels can have devastating consequences. Although lateral lumbar interbody fusion (LLIF) is an acceptable and minimally invasive alternative at the L5-S1 level, this approach is suboptimal because of a narrow surgical corridor limited by the iliac crest, common iliac artery and vein, and psoas. Furthermore, combining supine L5-S1 ALIF and lateral decubitus (LD) LLIF requires time-consuming patient repositioning.^1,2 To maximize the advantages of both procedures in patients with disease spanning the lumbosacral junction, ALIF and LLIF can be performed in a single stage with the patient remaining in an LD position throughout. To improve the efficiency of this single-position procedure, a fluoroscopy-based instrument tracking system (TrackX Technology Inc., Hillsborough, North Carolina, USA) was used to navigate surgical tools during the procedure. We show this technique in a 43-year-old patient with medically intractable back and leg pain secondary to multi-level degenerative lumbar spondylosis. The patient consented to this procedure; all participants consented to publication of their images. This tracking system allowed for accurate and precise virtual projections of surgical instruments, thereby facilitating the identification of midline and proper trajectories to perform discectomy and implant placement, reducing the amount of intraoperative fluoroscopy use, and eliminating intraoperative computed tomography. To our knowledge, this is the first operative video showing a fluoroscopy-based instrument tracking system used in a combined single-position LD-ALIF and LD-LLIF.

Multi-layer approach to complex traumatic anterior skull base fracture repair: A case report

Background

Anterior skull base fractures represent a unique challenge for neurosurgical repair due to the potential for orbital injury and the proximity to the air sinuses, yielding increased possibility for infection, and persistent cerebrospinal fluid (CSF) leak. While multiple techniques are available for the repair of anterior skull base defects, there exists a paucity of robust, long-term clinical data to guide the optimal surgical management of these fractures.

Case Description

We present the case of a complex, traumatic penetrating anterior skull base fracture, and describe a multi-layered approach for successful repair - namely, with the use of a temporally-based pericranial flap, split-thickness frontal bone graft, and autogenous abdominal fat graft. The patient was followed for nine months postoperatively, over which time she experienced no significant complications.

Conclusion

The goal of successful anterior skull base repair involves creating a durable, watertight separation between intra and extracranial compartments to prevent CSF leak, protect intracranial structures, and minimize infection risk. The temporally-based pericranial flap, split-thickness frontal bone graft, and autogenous abdominal fat graft represent safe and efficacious approaches to achieve lasting repair.

Data-driven phenotyping of preoperative functional decline patterns in patients undergoing lumbar decompression and lumbar fusion using smartphone accelerometry

OBJECTIVE

Treatment of degenerative lumbar spine pathologies typically escalates to surgical intervention when symptoms begin to significantly impair patients’ functional status. Currently, surgeons rely on subjective patient assessments through patient-reported outcome measures to estimate the decline in patient wellness and quality of life. In this analysis, the authors sought to use smartphone-based accelerometry data to provide an objective, continuous measurement of physical activity that might aid in effective characterization of preoperative functional decline in different lumbar spine surgical indications.

METHODS

Up to 1 year of preoperative activity data (steps taken per day) from 14 patients who underwent lumbar decompression and 15 patients who underwent endoscopic lumbar fusion were retrospectively extracted from patient smartphones. A data-driven algorithm was constructed based on 10,585 unique activity data points to identify and characterize the functional decline of patients preceding surgical intervention. Algorithmic estimation of functional decline onset was compared with reported symptom onset in clinical documentation across patients who presented acutely (≤ 5 months of symptoms) or chronically (> 5 months of symptoms).

RESULTS

The newly created algorithm identified a statistically significant decrease in physical activity during measured periods of functional decline (p = 0.0020). To account for the distinct clinical presentation phenotypes of patients requiring lumbar decompression (71.4% acute and 28.6% chronic) and those requiring lumbar fusion (6.7% acute and 93.3% chronic), a variable threshold for detecting clinically significant reduced physical activity was implemented. The algorithm characterized functional decline (i.e., acute or chronic presentation) in patients who underwent lumbar decompression with 100% accuracy (sensitivity 100% and specificity 100%), while characterization of patients who underwent lumbar fusion was less effective (accuracy 26.7%, sensitivity 21.4%, and specificity 100%). Adopting a less-permissive detection threshold in patients who underwent lumbar fusion, which rendered the algorithm robust to minor fluctuations above or below the chronically decreased level of preoperative activity in most of those patients, increased functional decline classification accuracy of patients who underwent lumbar fusion to 66.7% (sensitivity 64.3% and specificity 100%).

CONCLUSIONS

In this study, the authors found that smartphone-based accelerometer data successfully characterized functional decline in patients with degenerative lumbar spine pathologies. The accuracy and sensitivity of functional decline detection were much lower when using non–surgery-specific detection thresholds, indicating the effectiveness of smartphone-based mobility analysis in characterizing the unique physical activity fingerprints of different lumbar surgical indications. The results of this study highlight the potential of using activity data to detect symptom onset and functional decline in patients, enabling earlier diagnosis and improved prognostication.

Intra-operative wearable visualization in spine surgery: past, present, and future

The history of modern surgery has run parallel to the invention and development of intra-operative visualization techniques. The first operating room, built in 1804 at Pennsylvania Hospital, demonstrates this principle: illumination of the surgical field by the Sun through an overhead skylight allowed surgeries to proceed even prior to the invention of anesthesia or sterile technique. Surgeries were restricted to begin around when the Sun was at its zenith; without adequate light from the Sun and skylight, surgeons were unable to achieve adequate visualization. In the years since, new visualization instruments have expanded the scope and success of surgical intervention. Spine surgery in particular has benefited greatly from improved visualization technologies, due to the complex and intricate nervous, vascular and musculoskeletal structures that are closely intertwined which surgeons must manipulate. Over time, new technologies have also advanced to take up smaller footprints, leading to the rise of wearable tools that surgeons don intra-operatively to better visualize the surgical field. As surgical techniques shift to more minimally invasive methods, reliable, fidelitous, and ergonomic wearables are of growing importance. Here, we discuss the past and present of wearable visualization tools, from the first surgical loupes to cutting-edge augmented reality (AR) goggles, and comment on how emerging innovations will continue to revolutionize spine surgery.

Developing a Prediction Model for Identification of Distinct Perioperative Clinical Stages in Spine Surgery With Smartphone-Based Mobility Data

BACKGROUND

Spine surgery outcomes assessment currently relies on patient-reported outcome measures, which satisfy established reliability and validity criteria, but are limited by the inherently subjective and discrete nature of data collection. Physical activity measured from smartphones offers a new data source to assess postoperative functional outcomes in a more objective and continuous manner.

OBJECTIVE

To present a methodology to characterize preoperative mobility and gauge the impact of surgical intervention using objective activity data garnered from smartphone-based accelerometers.

METHODS

Smartphone mobility data from 14 patients who underwent elective lumbar decompressive surgery were obtained. A time series analysis was conducted on the number of steps per day across a 2-year perioperative period. Five distinct clinical stages were identified using a data-driven approach and were validated with clinical documentation.

RESULTS

Preoperative presentation was correctly classified as either a chronic or acute mobility decline in 92% of patients, with a mean onset of acute decline of 11.8 ± 2.9 weeks before surgery. Postoperative recovery duration demonstrated wide variability, ranging from 5.6 to 29.4 weeks (mean: 20.6 ± 4.9 weeks). Seventy-nine percentage of patients ultimately achieved a full recovery, associated with an 80% ± 33% improvement in daily steps compared with each patient's preoperative baseline (P = .002). Two patients subsequently experienced a secondary decline in mobility, which was consistent with clinical history.

CONCLUSION

The perioperative clinical course of patients undergoing spine surgery was systematically classified using smartphone-based mobility data. Our findings highlight the potential utility of such data in a novel quantitative and longitudinal surgical outcome measure.

Use of the LACE+ index to predict readmissions after single-level lumbar fusion

OBJECTIVE

Spinal fusion is one of the most common neurosurgical procedures. The LACE (length of stay, acuity of admission, Charlson Comorbidity Index [CCI] score, and emergency department [ED] visits within the previous 6 months) index was developed to predict readmission but has not been tested in a large, homogeneous spinal fusion population. The present study evaluated use of the LACE+ score for outcome prediction after lumbar fusion.

METHODS

LACE+ scores were calculated for all patients (n = 1598) with complete information who underwent single-level, posterior-only lumbar fusion at a single university medical system. Logistic regression was performed to assess the ability of the LACE+ score as a continuous variable to predict hospital readmissions within 30 days (30D), 30-90 days (30-90D), and 90 days (90D) of the index operation. Secondary outcome measures included ED visits and reoperations. Subsequently, patients with LACE+ scores in the bottom decile were exact matched to the patients with scores in the top 4 deciles to control for sociodemographic and procedural variables.

RESULTS

Among all patients, increased LACE+ score significantly predicted higher rates of readmissions in the 30D (p < 0.001), 30-90D (p = 0.001), and 90D (p < 0.001) postoperative windows. LACE+ score also predicted risk of ED visits at all 3 time points and reoperations at 30-90D and 90D. When patients with LACE+ scores in the bottom decile were compared with patients with scores in the top 4 deciles, higher LACE+ score predicted higher risk of readmissions at 30D (p = 0.009) and 90D (p = 0.005). No significant difference in hospital readmissions was observed between the exact-matched cohorts.

CONCLUSIONS

The present results suggest that the LACE+ score demonstrates utility in predicting readmissions within 30 and 90 days after single-level lumbar fusion. Future research is warranted that utilizes the LACE+ index to identify strategies to support high-risk patients in a prospective population.

Objective Outcomes in Lateral Osteotomy Through Anterior-to-Psoas for Severe Adult Degenerative Spine Deformity Correction

Multilevel lateral interbody fusion is an acceptable surgical technique in patients with severe degenerative adult spinal deformity (ASD). The current standard-of-care in spine surgery includes the use of patient reported outcome measures (PROMs) to assess post-operative improvement. Objective activity data during the peri-operative period may provide supplementary information for patients recovering from ASD surgery. In this report, we use smartphone-based activity data as an objective outcome measure for a patient who underwent a two-stage operation for ASD corrective surgery: lateral osteotomy and lumbar interbody fusion with posterior column release. An 82-year-old male presented with intractable back pain secondary to severe thoracolumbar scoliotic deformity (Lenke 5BN). Pre-operative images demonstrated the presence of bridging osteophytes over the left lateral aspect of L2-5 disc spaces and over the apex of the lumbar curvature, with significant neuroforaminal stenosis. Surgical correction was completed in two stages: (1) left-sided lateral osteotomy using anterior-to-psoas approach (ATP) in a right lateral decubitus position, and (2) multilevel Ponte osteotomies and instrumented fusion from T10-pelvis. Post-operative radiography showed correction to scoliotic deformity and sagittal misalignment. The patient had developed seroma and wound dehiscence, which was evacuated on post-operative day 11. At 14-month follow-up, the patient reported significant improvement in pain symptoms, corroborated by patient reported outcome measures. To further quantify and assess patient recovery, smartphone-based patient activity data was collected and analyzed to serve as a proxy for the patient's functional improvement. The patient's walking steps-per-day was compared pre- and post-operatively. The patient's pre-operative baseline was 223 steps/day; the patient's activity during immediate post-operative recovery dropped to 179 steps/day; the patient returned to baseline activity levels approximately 3 months after surgery, reaching an average of 216 steps/day. In conclusion, we found that lateral osteotomy through an ATP approach is a powerful tool to restore normal spine alignment and can be successfully performed using anatomic landmarks. Additionally, smartphone-based mobility data can assess pre-operative activity level and allow for remote patient monitoring beyond routine follow-up schedule.

Using smartphone-based accelerometers to gauge postoperative outcomes in patients with NPH: Implications for ambulatory monitoring

Background

The surgical treatment of normal pressure hydrocephalus (NPH) with shunting remains controversial due to the difficulty in distinguishing such pathology from other neurological conditions that can present similarly. Thus, patients with suspected NPH should be carefully selected for surgical intervention. Historically, clinical improvement has been measured by the use of functional grades, alleviation of symptoms, and/or patient/family-member reported surveys. Such outcome analysis can be subjective, and there is difficulty in quantifying cognition. Thus, a push for a more quantifiable and objective investigation is warranted, especially for patients with idiopathic NPH (INPH), for which the final diagnosis is confirmed with postoperative clinical improvement. We aimed to use Apple Health (Apple Inc., Cupertino, CA) data to approximate physical activity levels before and after shunt placement for NPH as an objective outcome measurement. The patients were contacted and verbally consented to export Apple Health activity data. The patient's physical activity data were then analyzed. A chart review from the patient's EMR was performed to understand and better correlate recovery.

Case Description

Our first patient had short-term improvements in activity levels when compared to his preoperative activity. The patient's activity level subsequently decreased at 6 months and onward. This decline was simultaneous to new-onset lumbar pain. Our second patient experienced sustained improvements in activity levels for 12 months after his operation. His mobility data were in congruence with his subjectively reported improvement in clinical symptoms. He subsequently experienced a late-decline that began at 48-months. His late deterioration was likely confounded by exogenous factors such as further neurodegenerative diseases coupled with old age.

Conclusion

The use of objective activity data offers a number of key benefits in the analysis of shunted patients with NPH/INPH. In this distinctive patient population, detailed functional outcome analysis is imperative because the long-term prognosis can be affected by comorbid factors or life expectancy. The benefits from using smartphone-based accelerometers for objective outcome metrics are abundant and such an application can serve as a clinical aid to better optimize surgical and recovery care.

Short-Term Impact of Bracing in Multi-Level Posterior Lumbar Spinal Fusion

BACKGROUND

Clinical practice in postoperative bracing after posterior lumbar spine fusion (PLF) is inconsistent between providers. This paper attempts to assess the effect of bracing on short-term outcomes related to safety, quality of care, and direct costs.

METHODS

Retrospective cohort analysis of consecutive patients undergoing multilevel PLF with or without bracing (2013-2017) was undertaken (n = 980). Patient demographics and comorbidities were analyzed. Outcomes assessed included length of stay (LOS), discharge disposition, quality-adjusted life years (QALY), surgical-site infection (SSI), total cost, readmission within 30 days, and emergency department (ED) evaluation within 30 days.

RESULTS

Amongst the study population, 936 were braced and 44 were not braced. There was no difference between the braced and unbraced cohorts regarding LOS (P = .106), discharge disposition (P = .898), 30-day readmission (P = .434), and 30-day ED evaluation (P = 1.000). There was also no difference in total cost (P = .230) or QALY gain (P = .740). The results indicate a significantly lower likelihood of SSI in the braced population (1.50% versus 6.82%, odds ratio = 0.208, 95% confidence interval = 0.057-0.751, P = .037). There was no difference in relevant comorbidities (P = .259-1.000), although the braced cohort was older than the unbraced cohort (63 versus 56 y, P = .003).

CONCLUSION

Bracing following multilevel posterior lumbar fixation does not alter short-term postoperative course or reduce the risk for early adverse events. Cost analysis show no difference in direct costs between the 2 treatment approaches. Short-term data suggest that removal of bracing from the postoperative regimen for PLF will not result in increased adverse outcomes.

Do-It-Yourself Augmented Reality Heads-Up Display (DIY AR-HUD): A Technical Note

BACKGROUND

We present a "Do-It-Yourself" method to build an affordable augmented reality heads-up display system (AR-HUD) capable of displaying intraoperative images. All components are commercially available products, which the surgeons may use in their own practice for educational and research purposes.

METHODS

Moverio BT 35-E smart glasses were connected to operating room imaging modalities (ie, fluoroscopy and 3D navigation platforms) via a high-definition multimedia interface (HDMI) converter, allowing for continuous high-definition video transmission. The addition of an HDMI transmitter-receiver makes the AR-HUD system wireless.

RESULTS

We used our AR-HUD system in 3 patients undergoing instrumented spinal fusion. AR-HUD projected fluoroscopy images onto the surgical field, eliminating shift of surgeon focus and procedure interruption, with only a 40- to 100-ms delay in transmission, which was not clinically impactful.

CONCLUSIONS

An affordable AR-HUD capable of displaying real-time information into the surgeon's view can be easily designed, built, and tested in surgical practice. As wearable heads-up display technology continues to evolve rapidly, individual components presented here may be substituted to improve its functionality and usability. Surgeons are in a unique position to conduct clinical testing in the operating room environment to optimize the augmented reality system for surgical use.

Using Smartphone-Based Accelerometer Data to Objectively Assess Outcomes in Spine Surgery

BACKGROUND

In order to deliver optimal patient care, spine surgeons must integrate technological changes to arrive at novel measures of functional outcomes. Historically, subjective patient-reported outcome (PRO) surveys have been used to determine the relative benefit of surgical treatments. Using smartphone-based accelerometers, surgeons now have the ability to arrive at objective outcome metrics.

OBJECTIVE

To use Apple Health (Apple Inc, Cupertino, California) data to approximate physical activity levels before and after spinal fusion as an objective outcome measurement.

METHODS

Personal activity data were acquired retrospectively from the cellphones of consenting patients. These data were used to measure changes in activity level (daily steps, flights climbed, and distance traveled) before and after patients underwent spine surgery at a single institution by a single surgeon. After data collection, we investigated the demographic information and daily physical activity pre- and postoperatively of participating patients.

RESULTS

Twenty-three patients were included in the study. On average, patients first exceeded their daily 1-yr average distance walked, flights climbed, and steps taken at 10.3 ± 14, 7.6 ± 21.1, and 8 ± 9.9 wk, respectively. Mean flights climbed, distance traveled, and steps taken decreased significantly from 6 mo prior to surgery to 2 wk postoperatively. Distance traveled and steps taken significantly increased from 6 mo prior to surgery to 7 to 12 mo postoperatively.

CONCLUSION

We demonstrated a valuable supplement to traditional PROs by using smartphone-based activity data. This methodology yields a rich data set that has the potential to augment our understanding of patient recovery.

Development of an Intraoperative Pipeline for Holographic Mixed Reality Visualization During Spinal Fusion Surgery

Objective. Holographic mixed reality (HMR) allows for the superimposition of computer-generated virtual objects onto the operator's view of the world. Innovative solutions can be developed to enable the use of this technology during surgery. The authors developed and iteratively optimized a pipeline to construct, visualize, and register intraoperative holographic models of patient landmarks during spinal fusion surgery. Methods. The study was carried out in two phases. In phase 1, the custom intraoperative pipeline to generate patient-specific holographic models was developed over 7 patients. In phase 2, registration accuracy was optimized iteratively for 6 patients in a real-time operative setting. Results. In phase 1, an intraoperative pipeline was successfully employed to generate and deploy patient-specific holographic models. In phase 2, the registration error with the native hand-gesture registration was 20.2 ± 10.8 mm (n = 7 test points). Custom controller-based registration significantly reduced the mean registration error to 4.18 ± 2.83 mm (n = 24 test points, P < .01). Accuracy improved over time (B = -.69, P < .0001) with the final patient achieving a registration error of 2.30 ± .58 mm. Across both phases, the average model generation time was 18.0 ± 6.1 minutes (n = 6) for isolated spinal hardware and 33.8 ± 8.6 minutes (n = 6) for spinal anatomy. Conclusions. A custom pipeline is described for the generation of intraoperative 3D holographic models during spine surgery. Registration accuracy dramatically improved with iterative optimization of the pipeline and technique. While significant improvements and advancements need to be made to enable clinical utility, HMR demonstrates significant potential as the next frontier of intraoperative visualization.

Patient Participation With a Mobile Phone Application for Objective Activity Assessment Before and After Spinal Fusion

Background 

Evolution within spine surgery is driven by a surgeon’s desire for expertise and significant improvement in their patients’ quality of life. As surgeons move away from using subjective patient-reported outcome (PRO) surveys, there must be an alternative objective metric in its place. Modern iPhone (Apple Inc., Cupertino, CA) technology can be used to capture daily activity in a simple, non-user biased manner. These health data can be used to analyze objective functional status in conjunction with PRO surveys to measure surgical outcomes.

Methods 

Patients who underwent an awake transforaminal lumbar interbody fusion (TLIF) between 2014 and 2018 at our institution were identified. Patients were consented and instructed to download the application “QS Access” (Quantified Self Labs, San Francisco, CA). Following data collection, we analyzed the demographic information of patients who were reached to gauge participation and feasibility of data exportation.

Results

A total of 177 patients who underwent an awake TLIF at our institution were contacted. Of those who answered, 41 (44.6%) agreed to participate and 51 (55.4%) declined to participate. When comparing those who either participated or declined, there were no significant differences in age (p=0.145), sex (p=0.589), or ethnicity (p=0.686).

Conclusion 

Our pilot study examined the patient participation in the novel usage of Apple "Health" data, queried from "QS Access" (Quantified Self Labs), to objectively measure relative patient functional status surrounding spinal fusion. We demonstrated that a smartphone-based application was mostly well received by our patient cohort and has the potential to be used as an objective operative metric moving forward. 

Remote Virtual Spinal Evaluation in the Era of COVID-19

Background

With the COVID-19 pandemic disrupting many facets of our society, physicians and patients have begun using telemedicine as a platform for the delivery of health care. One of the challenges in implementing telemedicine for the spine care provider is completing a comprehensive spinal examination. Currently, there is no standardized methodology to complete a full spinal examination through telemedicine.

Methods

We propose a novel, remote spinal examination methodology that is easily implemented through telemedicine, where the patient is an active participant in the successful completion of his or her examination. This type of examination has been validated in a neurology setting. To facilitate the telemedicine visit, we propose that video instruction be shared with the patient prior to the telemedicine visit to increase the efficacy of the examination.

Results

Since the issuance of stay-at-home order across the states, many spine practices around the country have rapidly adopted and increased their telemedicine program to continue provide care for patients during COVID-19 pandemic. At a tertiary academic center in a busy metropolitan area, nearly 700 telemedicine visits were successfully conducted during a 4-week period. There were no remote visits being done prior to the shutdown.

Conclusions

Implementation of our proposed remote spinal examination has the potential to serve as a guideline for the spine care provider to efficiently assess patients with spine disease using telemedicine. Because these are only suggestions, providers should tailor examination to each individual patient's needs.

Level of Evidence

V.

Clinical Relevance

It is likely that physicians will incorporate telemedicine into health care delivery services even after the COVID-19 pandemic subsides because of telemedicine's efficiency in meeting patient needs. Using the standard maneuvers provided in our study, spine care providers can perform a nearly comprehensive spine examination through telemedicine. Further studies will be needed to validate the reproducibility and reliability of our methodology.

The LACE+ Index as a Predictor of 90-Day Supratentorial Tumor Surgery Outcomes

BACKGROUND

The LACE+ (Length of stay, Acuity of admission, Charlson Comorbidity Index [CCI] score, and Emergency department [ED] visits in the past 6 mo) index risk-prediction tool has never been successfully tested in a neurosurgery population.

OBJECTIVE

To assess the ability of LACE+ to predict adverse outcomes after supratentorial brain tumor surgery.

METHODS

LACE+ scores were retrospectively calculated for all patients (n = 624) who underwent surgery for supratentorial tumors at the University of Pennsylvania Health System (2017-2019). Confounding variables were controlled with coarsened exact matching. The frequency of unplanned hospital readmission, ED visits, and death was compared for patients with different LACE+ score quartiles (Q1, Q2, Q3, and Q4).

RESULTS

A total of 134 patients were matched between Q1 and Q4; 152 patients were matched between Q2 and Q4; and 192 patients were matched between Q3 and Q4. Patients with higher LACE+ scores were significantly more likely to be readmitted within 90 d (90D) of discharge for Q1 vs Q4 (21.88% vs 46.88%, P = .005) and Q2 vs Q4 (27.03% vs 55.41%, P = .001). Patients with larger LACE+ scores also had significantly increased risk of 90D ED visits for Q1 vs Q4 (13.33% vs 30.00%, P = .027) and Q2 vs Q4 (22.54% vs 39.44%, P = .039). LACE+ score also correlated with death within 90D of surgery for Q2 vs Q4 (2.63% vs 15.79%, P = .003) and with death at any point after surgery/during follow-up for Q1 vs Q4 (7.46% vs 28.36%, P = .002), Q2 vs Q4 (15.79% vs 31.58%, P = .011), and Q3 vs Q4 (18.75% vs 31.25%, P = .047).

CONCLUSION

LACE+ may be suitable for characterizing risk of certain perioperative events in a patient population undergoing supratentorial brain tumor resection.

Heart-Shaped Bilateral Medullary Pyramidal Infarction as a Pathognomonic Finding of Anterior Spinal Artery Occlusion

BACKGROUND

Unilateral anterior spinal artery (ASA) occlusion resulting in bilateral medullary pyramidal (BMP) infarction is a rare and devastating stroke subtype. We present two cases highlighting the diagnostic and clinical challenges of BMP infarction.

METHODS

Case reports and literature review.

RESULTS

A 57-year-old man rapidly had severe vomiting and diarrhea 2 h after a meal. Examination revealed bulbar weakness and areflexic tetraplegia. Respiratory failure developed, requiring intubation and mechanical ventilation. Brain magnetic resonance imaging (MRI) showed a heart-shaped region of diffusion abnormality, characteristic of BMP infarction. Cerebral angiography showed an occluded left vertebral artery with unilateral left-sided origin of ASA. The patient required tracheostomy and percutaneous gastrostomy tube and was discharged to rehabilitation, with little improvement of his tetraplegia at 3-month follow-up. A 43-year-old woman presented to the emergency department with acute onset of lower-extremity paresthesia and history of upper respiratory infection 2 weeks prior. Initial examination findings included bulbar weakness, dysphagia, hyporeflexia, and generalized weakness. After admission, she had severe respiratory distress and required intubation. Lumbar puncture was evaluated for Guillain-Barré syndrome, but cerebrospinal fluid protein concentration was normal. Changes on diffusion-weighted MRI of the brain showed the characteristic heart-shaped BMP infarction, indicating occlusion of a unilateral ASA. She required tracheostomy and percutaneous gastrostomy tube placement, with no paralysis resolution.

CONCLUSION

Acute BMP infarction may present with flaccid tetraplegia mimicking neuromuscular disorders. When the infarction is recognized early, intravenous thrombolysis can be considered to reduce morbidity of this rare stroke subtype.

The evolution of minimally invasive spine surgery

The field of minimally invasive spine surgery (MISS) has rapidly evolved over the past 3 decades. This review follows the evolution of techniques and principles that have led to significant advances in the field. While still representing only a subset of spine surgeries, MISS’s goals of reducing soft-tissue trauma and mitigating the morbidity of surgery are being realized, translating into more rapid recovery, lower infection rates, and higher cost savings. Future advances in technology and techniques can be anticipated.

Enterobacter Infection after Spine Surgery: An Institutional Experience

BACKGROUND

Gram-negative surgical site infections (SSI) following spine surgery are becoming increasingly more common owing to a broad perioperative antibiotic usage targeting gram-positive organisms. Enterobacter species have been reported to be the most common gram-negative bacteria following spine surgery.

METHODS

We queried our institutional database for Enterobacter SSIs after spine surgery at a single institution from 2009-2016. Relevant demographic, clinical, and operative variables were collected. We compared this cohort to patients who had non-Enterobacter SSI during the same period.

RESULTS

Enterobacter species were isolated in 16 patients (9 males) diagnosed with SSI after undergoing spine surgery. This group represented 0.2% of all spine cases and 14.5% of all spinal SSIs. Seven patients (43.8%) required multiple irrigations and debridements (I&Ds) (range: 2-8), whereas only 17 of 94 patients (18.1%) with non-Enterobacter SSI required multiple I&Ds (range: 2-5, P = 0.043). Those infected with Enterobacter were associated with higher BMI (37.6 ± 12.7 vs. 31.7 ± 8, P = 0.036), earlier wound dehiscence (14.8 vs. 24.6 days, P = 0.01), polymicrobial infections (37.5% vs. 10.6%, P = 0.012), and longer length of stay (18 days [9.5-31.5] vs. 5 days [3-8], P = 0.01) when compared to non-Enterobacter SSI cohort. At an average of 24.2 months follow-up, all 15 surviving patients were infection free with no further revision surgeries needed.

CONCLUSIONS

Enterobacter SSI cases were associated with higher BMI, earlier wound breakdown, polymicrobial infection and longer length of stay. Nevertheless, with vigilant surveillance and timely I&Ds, these challenging infections can be treated successfully with original implant retention in almost all cases.

Challenges of Managing Patients with Symptomatic Large Traumatic Cervical Pseudomeningoceles

BACKGROUND

Traumatic cervical pseudomeningoceles (TCPs) occur secondary to traction of the cervical nerve roots resulting in violation of the dura. Surgical repair is not necessary in most cases because pseudomeningoceles have a high propensity to spontaneously resolve with conservative management alone. Currently, there are a limited number of cases of large TCPs (large is defined as ≥6 cm in greatest diameter), and there is no established guideline for the management of such lesions.

CASE DESCRIPTION

We describe the cases of 2 young men in their 20s who were involved in a motor vehicle accident. Both patients suffered a brachial plexus injury and developed large TCPs. Patient 1 was treated surgically for TCP using a combined intra-/extradural approach using a fascia lata graft. Patient 2 was ultimately treated nonsurgically because a spontaneous resolution of the pseudomeningocele was achieved over the period of 7 months after the accident. Both patients underwent brachial plexus repair surgery consisting of spinal accessory nerve transfer to the suprascapular nerve and intercostal nerve transfer to the musculocutaneous nerve.

CONCLUSIONS

Disease progression of TCPs is a dynamic process, and even large lesions may spontaneously resolve without surgical intervention. When surgery is indicated, a definitive dural repair using a fascia lata graft to cover the dural tear intra- and extradurally is an effective method. Surgery must be planned carefully on a case-by-case basis, and close follow-up with thorough physical examination and serial imaging is critical to monitor disease progression.

Vertebral Venous Collaterals with Underlying Agenesis of the Inferior Vena Cava: Implications for Spinal Surgery

BACKGROUND

Congenital agenesis of the inferior vena cava (IVC) can lead to the development of a prominent venous collateral system within and around the spine due to the development of venous collaterals. In such patients, surgery can carry a risk of catastrophic bleeding or decompensation of a delicate venous drainage pattern during spinal manipulation or even epidural exploration.

CASE DESCRIPTION

A 49-year-old man with a congenital agenesis of the IVC presented with signs and symptoms of an L5 radiculopathy. A computed tomography scan of the lumbar spine showed the characteristic finding of fenestrated or "holey" pedicles within the lumbar spine, due to chronic venous engorgement within the pedicles.

CONCLUSIONS

To our knowledge, this is the first report to describe the characteristic sign of "holey" pedicles on radiographic imaging in a patient with an underdeveloped IVC. This finding may be useful for the detection of abnormal spinal venous anatomy. In such patients, spinal surgery may carry greater risks and requires special consideration.