The message of the Glasgow Coma Scale: a comprehensive bibliometric analysis and systematic review of clinical practice guidelines spanning the past 50 years

BACKGROUND

Despite the ubiquitous use and profound impact of the Glasgow Coma Scale (GCS), no study to date has quantitatively assessed its impact on scientific literature and clinical practice. Therefore, we comprehensively analyze scientific publications and clinical practice guidelines employing the GCS to gauge its clinical and academic impact, identify research hotspots, and inform future research.

METHODS

A cross-sectional bibliometric analysis was performed on Scopus to obtain relevant publications incorporating the GCS from 1974 to 2022. In addition, a systematic review of existing clinical practice guidelines in PubMed, Scopus, Web of Science, and Trip Database was performed. Validated bibliometric parameters including article title, journal, publication year, authors, citation count, country, institution, keywords, impact factor, and references were assessed. When evaluating clinical practice guidelines, the sponsoring organization, country of origin, specialty, and publication year were assessed.

RESULTS

A total of 37,633 articles originating from 3,924 different scientific journals spanning 1974 to 2022 were included in the final analysis. The compound annual growth rate was 16.7%. Of 104 countries, the United States had the highest total number of publications (n=8,517). World Neurosurgery was the scientific periodical with the highest number of publications (n=798). The top trending author-supplied keyword was "traumatic brain injury" (n=3,408). The 97 included clinical practice guidelines most commonly employed the GCS in the fields of internal medicine (n=22, 23%), critical care (n=21, 22%), and neurotrauma (n=19, 20%).

CONCLUSION

At the turn of the 50th anniversary of the GCS, we provided an objective description of the "path to success" of the GCS both in terms of its scientific and clinical impact. These results hold not only a historical but also a didactic value. Our analysis of some of the factors that led the GCS to become such a widespread and highly influential score may assist future researchers in their development of future outcome measures and clinical scores, especially as they become increasingly relevant in an evidence-based, data-driven age.

Traumatic pneumocephalus as a possible early sign of acute spinal cord injury: Case report

Background

Traumatic pneumocephalus (TPC) following craniofacial injuries is common, but isolated TPC secondary to pneumorrhachis (PR) is the rare result of upward gas migration from the spinal canal. In the absence of craniofacial and grossly unstable spinal fractures, the etiology of TPC in polytrauma can be elusive and an underlying diagnosis of acute spinal cord injury (SCI) can be easily missed. We report the first polytrauma case where TPC was the most reliable early sign of SCI.

Case Description

A 34-year-old polytrauma female with imaging findings of TPC, which was later found to be secondary to an underlying SCI. As a focused exam could not be performed at admission, the TPC was first attributed to undiagnosed craniofacial injuries. Tertiary survey revealed the patient being paraplegic and MRI workup demonstrated an acute SCI at the T3-T4 level. PR was the most likely cause of TPC in the absence of other craniofacial injuries.

Outcome

The patient did not have a meaningful recovery given the extensive hemispheric infarcts, spinal cord injury, and respiratory failure.

Conclusions

Although uncommon, TPC may be an important radiographic sign suggesting the possibility of an underlying SCI in polytrauma patients. especially when focused neurologic assessment is limited at admission. Polytrauma patients with TPC and PR in the absence of coexisting craniofacial fractures require an urgent spine consultation by the ER physician, with possible early spine MRI workup. We suggest a diagnostic algorithm for the early identification of SCI in polytrauma patients presenting with TPC and propose considering 3 groups which may have different risks for SCI based on their clinical presentation and the presence of PR.

The life and legacy of John Robert Cobb: the man behind the angle

In 1934, Dr. John Robert Cobb moved to New York to serve as the Gibney Orthopedic Fellow at the Hospital for the Ruptured and Crippled, now known as the Hospital for Special Surgery. In this role, Cobb was faced with a unique task that would shape not only his personal career but also the fields of scoliosis and spine care: to design the first scoliosis specialty clinic. He critically reviewed the treatment methods for scoliosis outlined by prior pioneers in spine surgery and kept his own meticulous records of diagnoses, treatments, and radiographs. Cobb's work culminated in major contributions to spine surgery that are highly relevant to this day, including the Cobb angle and the Cobb elevator. In this detailed analysis of the career and academic legacy of Dr. John R. Cobb, the authors examine in detail the historical events surrounding Cobb's great contributions to spine surgery and their lasting impact on our specialty, as well as unique aspects of his personal life. This historical vignette constitutes the first comprehensive analysis of the life, career, and academic legacy of Dr. John R. Cobb, the man behind the angle.

Outcome Reporting in Spine Surgery: A Review of Historical and Emerging Trends

The general objectives of spine surgery are to alleviate pain, restore neurologic function, and prevent or treat spinal deformities or instability. The accumulating expanse of outcome measures has allowed us to more objectively quantify these variables and, therefore, gauge the success of treatments, ultimately improving the quality of the delivered health care. It has become increasingly evident that spinal conditions and their accompanying interventions affect all aspects of a patient's life, including their physical, mental, emotional, and social well-being. This underscores the challenge of creating clinically relevant and accurate outcome measures in spine care, and the reason why there is a growing recognition of the importance of subjective measures such as patient-reported outcome measures, that consider a patients' health-related quality of life. Subjective measures provide valuable insights into patient experiences and perceptions of treatment outcomes, whereas objective measures provide a reproducible glimpse into key radiographic and clinical parameters that are associated with a successful outcome. In this narrative review, we provide a detailed analysis of the most common subjective and objective outcome measures employed in spine surgery, with a special focus on their current role as well as the possible future of outcome reporting.

Development of a Modified Bayonet Forceps for Improving Steerability of Paddle Lead Electrodes During Spinal Cord Stimulator Surgery: A Technical Note

BACKGROUND AND OBJECTIVE

Despite recent advancements in spinal cord stimulation (SCS) technology, the surgical instrumentation for placement of SCS paddle leads remains suboptimal. Therefore, we developed a novel instrument to improve the steerability of SCS paddle leads during surgical placement.

METHODS

A review of existing literature was performed to analyze workflow deficiencies in the standard instrumentation of SCS paddle lead placement. After a period of adaptation and iterative feedback with a medical instrument company, a new instrument was developed, tested at benchtop, and successfully incorporated into the surgical routine.

RESULTS

A standard bayonet forceps was modified to include hooked ends and a ribbed surface, providing the surgeon with greater control over the paddle lead. The new instrument also included bilateral metal tubes starting approximately 4 cm proximal from the edge of the forceps. The bilateral metal tubes, through which the SCS paddle lead wires are passed, serve as anchors to keep the wires away from the incision site. In addition, it permitted the paddle lead to assume a bent configuration, reducing its overall size and allowing it to be placed through a smaller incision and laminectomy. The modified bayonet forceps was successfully used intraoperatively for placement of SCS paddle lead electrodes in several surgeries.

CONCLUSION

The proposed modified bayonet forceps increased steerability of the paddle lead, facilitating optimal midline placement. The bent configuration of the device facilitated a more minimally invasive surgical approach. Future studies are needed to validate our single-provider experience and evaluate the impact of this new instrument on operating room efficiency.

Complex surgical reconstruction for spinopelvic instability caused by a giant Tarlov cyst eroding the sacrum: A case report

Background

Tarlov cysts (TC), also known as perineural cysts are meningeal dilations of the posterior nerve root sheath that typically affect sacral nerve roots. TC are usually asymptomatic and found incidentally. We present the case of a patient with an enlarging sacral TC causing pain from spinopelvic instability secondary to extensive bone erosion. Such illustrative case is intended to increase awareness of the potential need for complex spinopelvic reconstruction in atypical instances of large TC.

Case Description

A 29-year-old female presented to clinic reporting progressive bilateral sacroiliac joint pain that was essentially mechanical in nature. The patient had a normal neurological exam except for a known left drop foot with numbness in the left sural nerve distribution, both attributed to a previously resected peripheral nerve sheath tumor. Magnetic resonance imaging revealed a large multilobulated lesion with imaging characteristics consistent with TC adjacent to the left side of the sacrum, extending outward from the left S1 and S2 neural foramina and measuring 6.7 × 3.7 cm in the axial plane and and 5.6 cm in the sagittal plane. Six weeks of conservative management consisting of physical therapy and pain management was unsuccessful, and the patient reported worsening pain. Surgical reconstruction consisting of L5-S1 transforaminal lumbar interbody fusion, L4 to pelvis navigation-guided instrumentation and posterolateral fusion, and bilateral sacroiliac joint fusion was successfully performed.

Outcomes

At 12 weeks follow-up appointment after surgery, the patient reported resolution of sacroiliac mechanical pain.

Conclusions

Sacral TC are asymptomatic in their vast majority of cases but may occasionally cause neurological deficits secondary to mass effect. Rarely, however, giant TC can also lead to significant bone erosion or the sacrum with secondary spinopelvic instability. In this brief report, we describe a giant TC generating significant spinopelvic instability, which was successfully treated with complex spinopelvic reconstruction, leading to complete resolution of the reported axial mechanical pain.

Expert Witness Testimony in Spine Surgery: A Review of Guidelines and Recommendations From Professional Organizations

BACKGROUND

Most professional spine societies have enacted formal guidelines for spine surgeons providing expert witness services. However, there is significant heterogeneity in existing recommendations, with most societies providing information that is limited in detail and scope.

OBJECTIVE

To provide a review of guidelines published by professional spine societies for spine surgeons serving as expert witnesses.

METHODS

The Gale Directory Library, PubMed, and the grey literature were queried for national or international professional societies related to spine surgery. The search was focused on societies in the United States and North America, but also included well recognized international organizations in the field of spine surgery. Included societies with publicly available guidelines regarding expert witness services were extracted for 4 domains: (1) qualifications, (2) preparations, (3) testimony, and (4) compensation as well as the presence of a professional compliance program, defined as any official subcommittee aimed toward investigating claims of unethical behavior.

RESULTS

Although most professional spine societies share general themes with respect to expert witness guidelines, important differences exist. Of the 26 societies included, 10 included publicly available guidelines: 4 of which were general neurosurgery societies, 2 general orthopedic surgery, and 4 spine specific. Three societies included the guidelines on all 4 domains (ie, qualifications, preparations, testimony, and compensation), and 2 societies included only 1 of the 4 domains. Eight societies possess a professional compliance program.

CONCLUSION

There remains a paucity in expert witness guidelines provided by professional spine societies. Although existing recommendations are useful, there is a lack of standardized and comprehensive materials for spine surgeons providing expert witness testimony to reference. Moving forward, joint committees comprising surgeons, attorneys, and patient stakeholders may help improve the guidelines.

Litigation involving sports-related spinal injuries: a comprehensive review of reported legal claims in the United States in the past 70 years

BACKGROUND CONTEXT

Sports-related spinal injuries can be catastrophic in nature. Athletes competing in collision sports (eg, football) may be particularly prone to injury given the high-impact nature of these activities. Due to the oftentimes profound impact of sports-related spinal injuries on health and quality-of-life, they are also associated with a substantial risk of litigation. However, no study to date has assessed litigation risks associated with sports-related spinal injuries. A better understanding of the risk factors surrounding these legal claims may provide insights into injury prevention and other strategies to minimize litigation risks. In addition, it may allow the spine surgeon to better recognize the health, socioeconomic, and legal challenges faced by this patient population.

PURPOSE

To provide a comprehensive assessment of reported legal claims involving sports-related spinal injuries, including a comparative analysis of legal outcomes between collision and non-collision sports. To discuss strategies to prevent sports-related spinal injuries and minimize litigation risks.

STUDY DESIGN/SETTING

Retrospective review.

PATIENT SAMPLE

Athletes experiencing spinal injuries during sports.

OUTCOME MEASURES

Outcomes included verdict outcome (defendant vs. plaintiff), legal claims, injuries sustained, clinical symptoms, and award payouts.

METHODS

The legal research database Westlaw Edge (Thomson Reuters) was queried for legal claims brought in the United States from 1950 to 2021 involving sports-related spinal injuries. Verdict or settlement outcomes were collected as well as award payouts, time to case closure, case year, and case location. Demographic data, including type of sport (ie collision vs. non-collision sport) and level of play were obtained. Legal claims, spinal injuries sustained, and clinical symptoms were also extracted. Furthermore, the nature of injury, injured spinal region, and treatment pursued were collected. Descriptive statistics were reported for all cases and independent-samples t-tests and chi-square tests were used to compare differences between collision and non-collision sports.

RESULTS

Of the 840 cases identified on initial search, 78 met our criteria for in-depth analysis. This yielded 62% (n=48) defendant verdicts, 32% (n=25) plaintiff verdicts, and 6% (n=5) settlements, with a median inflation-adjusted award of $780,000 (range: $5,480-$21,585,000) for all cases. The most common legal claim was negligent supervision (n=38, 46%), followed by premises liability (n=23, 28%), and workers' compensation/no fault litigation (n=10, 12%). The most common injuries sustained were vertebral fractures (n=34, 44%) followed by disc herniation (n=14, 18%). Most cases resulted in catastrophic neurological injury (n=37, 49%), either paraplegia (n=6, 8%) or quadriplegia (n=31, 41%), followed by chronic/refractory pain (n=32, 43%). Non-collision sport cases had a higher percentage of premises liability claims (41% vs. 11%, p=.006) and alleged chronic/refractory pain (53% vs. 28%, p=.04). Conversely, collision sport cases had a higher proportion of workers' compensation/no fault litigation (23% vs. 4%, p=.03) and cases involving disc herniation (29% vs. 9%, respectively; p=.04).

CONCLUSION

Sports-related spinal injuries are associated with multiple and complex health, socioeconomic, and legal consequences, with median inflation-adjusted award payouts nearing $800,000 per case. In our cohort, the most commonly cited legal claims were negligent supervision and premises liability, emphasizing the need for prevention guidelines for safe sports practice, especially in non-professional settings. Cases involving athletes participating in non-collision sports were significantly associated with claims citing chronic/refractory pain, highlighting the importance of long-term care in severely injured athletes.

Blast-Related Traumatic Brain Injuries Secondary to Thermobaric Explosives: Implications for the War in Ukraine

Blast-related traumatic brain injury (bTBI) is a significant cause of wartime morbidity and mortality. In recent decades, thermobaric explosives have emerged as particularly devastating weapons associated with bTBI. With recent documentation of the use of these weapons in the war in Ukraine, clinicians and laypersons alike could benefit from an improved understanding behind the dynamic interplay between explosive weaponry, its potential for bTBI, and the subsequent long-term consequences of these injuries. Therefore, we provide a general overview of the history and mechanism of action of thermobaric weapons and their potential to cause bTBI. In addition, we highlight the long-term cognitive and neuropsychiatric sequelae following bTBI and discuss diagnostic, therapeutic, and rehabilitation strategies, with the aim of helping to guide mitigation strategies and humanitarian relief in Ukraine. Thermobaric weapons produce a powerful blast wave capable of causing bTBIs, which can be further classified from primary to quaternary injuries. When modeling the hypothetical use of thermobaric weapons in Odessa, Ukraine, we estimate that the detonation of a salvo of thermobaric rockets has the potential to affect approximately 272 persons with bTBIs. In addition to the short-term damage, patients with bTBIs can present with long-term symptoms (e.g., post-traumatic stress disorder), which incur substantial financial costs and social consequences. Although these results are jarring, history has seen radical advancements in the understanding, diagnosis, and management of bTBI. Moving forward, a better understanding of the mechanism and long-term sequelae of bTBIs could help guide humanitarian relief to those affected by the war in Ukraine.

Malpractice litigation in elective lumbar spinal fusion: a comprehensive review of reported legal claims in the U.S. in the past 50 years

BACKGROUND CONTEXT

In the U.S., medical malpractice litigation is associated with significant financial costs and often leads to the practice of defensive medicine. Among medical subspecialities, spine surgery is disproportionately impacted by malpractice claims.

PURPOSE

To provide a comprehensive assessment of reported malpractice litigation claims involving elective lumbar spinal fusion (LSF) surgery during the modern era of spine surgery instrumentation in the U.S., to identify factors associated with verdict outcomes, and to compare malpractice claims characteristics between different approaches for LSF.

STUDY DESIGN/SETTING

A retrospective review.

PATIENT SAMPLE

Patients undergoing elective lumbar spinal fusion surgery.

OUTCOME MEASURES

The primary outcome measure was verdict outcome (defendant vs. plaintiff verdict). Secondary outcome measures included alleged malpractice, injury/damage claimed, and award payouts.

METHODS

The Westlaw legal database (Thomson Reuters, New York, NY, USA) was queried for verdict and settlement reports pertaining to elective LSF cases from 1970 to 2021. Data were collected regarding patient demographics, surgeon specialty, fellowship training, state/region, procedure, institutional setting (academic vs. community hospital), alleged malpractice, injury sustained, case outcomes, and monetary award.

RESULTS

A total of 310 cases were identified, yielding 67% (n=181) defendant and 24% (n=65) plaintiff verdicts, with 9% (n=26) settlements. Neurosurgeons and orthopedic spine surgeons were equally named as the defendant (45% vs. 51% respectively, p=0.59). When adjusted for inflation, the median final award for plaintiff verdicts was $1,241,286 (95% CI: $884,850-$2,311,706) while the median settlement award was $925,000 (95% CI: $574,800-$1,787,130), with no stastistically significant differences between verdict and reported settlement payouts (p=0.49). The Northeast region displayed significantly higher award payouts compared to other U.S. regions (p=0.02). There were no associations in awards outcomes when comparing alleged malpractice, alleged injuries/damages, institutional setting, surgical procedures, and surgeon specialty or fellowship training. The most common claims were intraoperative error (28%, n=107) followed by failure to obtain informed consent (24%, n=94). In the analyzed cohort, the most common injuries leading to litigation were refractory pain and suffering (37%, n=149) followed by permanent neurological deficits (26%, n=106). There were no differences in alleged malpractice or injury sustained between cases in which the outcome was favorable to defendant versus plaintiff. Anterior lumbar interbody fusion (ALIF) cases were 2.75 times more likely to be cited for excessive or inappropriate surgery (OR: 2.75 [95% CI: 1.14, 6.86], p=0.02) when compared to posterior surgical approaches.

CONCLUSION

The results of our analysis of reported claims suggest that medical malpractice litigation involving elective LSF is associated with jury verdicts over $1 million per case, with the most common alleged malpractice being intraoperative error and failure to obtain informed consent. Surgeon specialty, fellowship training, procedure type, and institution type were not associated with greater litigation risks; however, ALIF surgery had a significantly higher risk of involving claims of excessive or inappropriate surgery compared to posterior approaches for lumbar fusion. In addition, claims were significantly higher in the Northeast compared to other U.S. regions. Efforts to improve patient education through shared-decision making and proactive strategies to avoid, detect, and mitigate intra-operative procedural errors may decrease the risk of litigation in elective LSF.

Educational impact of early COVID-19 operating room restrictions on neurosurgery resident training in the United States: A multicenter study

Background

The coronavirus (COVID-19) pandemic has caused unprecedented suspensions of neurosurgical elective surgeries, a large proportion of which involve spine procedures. The goal of this study is to report granular data on the impact of early COVID-19 pandemic operating room restrictions upon neurosurgical case volume in academic institutions, with attention to its secondary impact upon neurosurgery resident training. This is the first multicenter quantitative study examining these early effects upon neurosurgery residents caseloads.

Methods

A retrospective review of neurosurgical caseloads among seven residency programs between March 2019 and April 2020 was conducted. Cases were grouped by ACGME Neurosurgery Case Categories, subspecialty, and urgency (elective vs. emergent). Residents caseloads were stratified into junior (PGY1-3) and senior (PGY4-7) levels. Descriptive statistics are reported for individual programs and pooled across institutions.

Results

When pooling across programs, the 2019 monthly mean (SD) case volume was 214 (123) cases compared to 217 (129) in January 2020, 210 (115) in February 2020, 157 (81), in March 2020 and 82 (39) cases April 2020. There was a 60% reduction in caseload between April 2019 (207 [101]) and April 2020 (82 [39]). Adult spine cases were impacted the most in the pooled analysis, with a 66% decrease in the mean number of cases between March 2020 and April 2020. Both junior and senior residents experienced a similar steady decrease in caseloads, with the largest decreases occurring between March and April 2020 (48% downtrend).

Conclusions

Results from our multicenter study reveal considerable decreases in caseloads in the neurosurgical specialty with elective adult spine cases experiencing the most severe decline. Both junior and senior neurosurgical residents experienced dramatic decreases in case volumes during this period. With the steep decline in elective spine cases, it is possible that fellowship directors may see a disproportionate increase in spine fellowships in the coming years. In the face of the emerging Delta and Omicron variants, programs should pay attention toward identifying institution-specific deficiencies and developing plans to mitigate the negative educational effects secondary to such caseloads reduction.

Long-term time series forecasting and updates on survival analysis of glioblastoma multiforme, a 1975-2018 population-based study

OBJECTIVE

Glioblastomas(GBM) are the most common primary CNS tumors. Epidemiologic studies have investigated the effect of demographics on patient survival, but the literature remains inconclusive.

METHODS

This study included all adult patients with intracranial GBMs reported in the SEER-9 population database (1975-2018). The sample consisted of 32746 unique entries. We forecast the annual GBM incidence in the US population through the year of 2060 using time series analysis with autoregressive moving averages. A survival analysis of the GBM-specific time to death was also performed. Multivariate Cox Proportional Hazards(PH) regression revealed frank violations of the PH assumption for multiple covariates. Parametric models best described the GBM population's survival pattern; the results were compared to the semi-parametric analysis and the published literature.

RESULTS

We predicted an increasing GBM incidence, which demonstrated that by the year 2060, over 1800 cases will be reported annually in the SEER. All eight demographic variables were significant in the univariable analysis. The calendar year 2005 was the cutoff associated with an increased survival probability. A male survival benefit was eliminated in the year-adjusted Cox. The factors: infratentorial tumors, non-metropolitan areas, and White patient race were erroneously associated with survival in the multivariate Cox analysis. AFT lognormal regression was the best model to describe the survival pattern in our patient population, identifying age > 30 years old as a poor prognostic and patients > 70 years old as having the worst survival. Annual income > $75,000 and supratentorial tumors were good prognostics, while surgical intervention provided the strongest survival benefit.

CONCLUSIONS

Annual GBM incidence rates will continue to increase by almost 50% in the upcoming 30 years. Cox regression analysis should not be utilized for time-to-event predictions in GBM survival statistics. AFT lognormal distribution best describes the GBM specific survival pattern, and as an inherent population characteristic, it should be implemented by researchers for future studies. Surgical intervention provides the strongest survival benefit, while patient age > 70 years old is the worst prognostic. Based on our study, the demographics: gender, race, and county type should not be considered as meaningful prognostics when designing future trials.

Misinterpretations of Null Hypothesis Significance Testing Results Near the P-value Threshold: An Estimation of The Prevalence of Such a Statistical Error In The Neurosurgical Literature

INTRODUCTION

Although statistical errors have been shown to be prevalent in the medical literature there has been a paucity of studies focusing on the prevalence of such errors in neurosurgery. In this article, we audit the contemporary neurosurgical literature for a common statistical mistake, namely, misinterpretations of null hypothesis significance testing results near the p-value threshold by conveying the idea of a "trend".

METHODS

PubMed/Medline was used to identify all articles published in six major neurosurgical journals between 2000 and 2020. The abstracts of these articles were extracted and scrutinized to determine when the word "trend" was used to express "near-statistical significance".

RESULTS

A total of 45,244 articles were included. Of those 461 (1.02% [0.86-1.18]) employed the word "trend" to indicate near statistical significance, a total of 3.8 [2.93-4.75] errors per issue per year. The error under study occurred more frequently in JNS Spine and less frequently in Acta Neurochirurgica (p=0.007). On an annual basis, there was no linear correlation between the total number of papers published per journal and the number of errors in that journal (r=0.34, p = 0.01).

CONCLUSION

Misinterpretations of null hypothesis significance testing results near the p-value threshold is present in at least 1% of the neurosurgical literature. While we believe that most statistical errors in medicine in general and neurosurgery in particular may be unintentional in nature, additional measures should be enacted to prevent the subsequent adoption of such methodological practices amongst future researchers.

Neurophysiological effects of various music genres on electroencephalographic (EEG) cerebral cortex activity

Background

Music has been associated with therapeutic properties for thousands of years across a vast number of diverse regions and cultures. This study expands upon our current understanding of music’s influence on human neurophysiology by investigating the effects of various music genres on cerebral cortex activity using electroencephalography (EEG).

Methods

A randomized, controlled study design was used. EEG data were recorded from 23 healthy adults, ages 19–28, while listening to a music sequence consisting of five randomized songs and two controls. The five studied music genres include: Classical, Tribal Downtempo, Psychedelic Trance (Psytrance), Goa Trance, and Subject Choice.

Results

Controls were associated with lower percentages of beta frequencies and higher percentages of alpha frequencies than the music genres. Psytrance was associated with higher percentages of theta and delta frequencies than the other music genres and controls. The lowest percentages of beta frequencies and highest percentages of alpha frequencies occurred in the occipital and parietal regions. The highest percentages of theta and delta frequencies occurred in the frontal and temporal regions. Subjects with prior music training exhibited increased percentages of delta frequencies in the frontal region. Subject gender and music preference did not have a significant influence on frequency band percentages.

Conclusions

Findings from this study support those of previous music therapy studies and provide novel insights regarding music’s influence on human neurophysiology. These findings also support the hypothesis that music may promote changes in cerebral cortex activity that have similarities to non-rapid eye movement (NREM) sleep, while the listener remains awake.

Surgical removal of a migrating intraspinal bullet: illustrative case

BACKGROUND

Management of gunshot wounds to the spine with subsequent spinal cord injury is a controversial topic among spine surgeons. Possible complications of retained intradural bullets include delayed neurological deficits, spinal instability, and lead toxicity. The authors’ purpose is to review the potential complications of retained intraspinal bullets and the surgical indications for intraspinal bullet removal.

OBSERVATIONS

The authors describe a case of a patient who developed cauda equina symptoms following a gunshot wound to the lumbar spine with a migrating retained intraspinal bullet. Because of neurological changes, the patient underwent surgical removal of the bullet. At the postoperative clinic visit 2 weeks following bullet removal, the patient reported resolution of her symptoms.

LESSONS

Gunshot wounds to the spine are challenging cases. The decision to proceed with surgical management in the event of retained bullet fragments is multifactorial and relies heavily on the patient’s neurological status. A current review of the literature suggests that, in cases of cauda equina injuries and the development of neurological deficits in patients with retained intraspinal fragments, there is benefit from surgical decompression and bullet removal. Careful preoperative planning is required, and consideration of spinal alignment with positional changes is crucial.

S3 Sacral-Alar Iliac Screw: A Salvage Technique for Pelvic Fixation in Complex Deformity Surgery

Sacral-alar iliac (SAI) screws constitute a relatively new technique for pelvic fixation. Since their initial description in 2007, SAI screws have gained wide popularity among the spine surgery community. In 2013, we first described the possibility of using both S1 and S2 SAI screws for pelvic fixation in revision surgeries for adult degenerative scoliosis. Although a previous radiological study has suggested the feasibility of S3 and S4 SAI screws, to the best of our knowledge, there has been no report in the literature on the clinical use of such techniques. In this brief technical note, we present the first clinical report of the use of S3 SAI screws as a salvage method for pelvic fixation in a patient with suboptimal anatomy that prevented proper placement of S1 and S2 SAI screws. We also discuss the recommended anatomical entry points and trajectory of such screws.

Should kyphoplasty curettes be used in nonosteoporotic patients? A cautionary tale

The authors present the first report of a fracture of the tip of a kyphoplasty curette inside the vertebral body, which occurred during a procedure in a patient with non-osteoporotic fracture. This highlights the need of further biomechanical research focused on the shear load failure properties of such type of pre-bent curettes.

Sources, Identification, and Clinical Implications of Heterogeneity in Human Umbilical Cord Stem Cells

Heterogeneity among different subpopulations of human umbilical cord mesenchymal stem cell (hUCMSCs) lines is an ubiquitous phenomenon, with such variability being related to several factors including the identity of the individual donor, tissue source (Wharton's jelly vs. umbilical cord blood), culture conditions, as well as random variations in the cloning expansion process. In this chapter, we provide a general overview on the sources as well as available experimental techniques for proper identification of heterogeneity in hUCMSCs. Finally, we provide a brief discussion on the current scientific evidence regarding the potential superiority of subpopulations of hUCMSCs for specific clinical applications. Taking into account the exponential growth on the available experimental data on hUCMSCs in the past few years, this chapter is not intended to be comprehensive in nature, but rather is intended to provide a general overview about the central role which the topic of heterogeneity has in both basic science and clinical research in umbilical cord stem cells.

Development of a New Coupled Cobb-Suction Instrument for Posterior Spinal Approaches: Technical Note

BACKGROUND

During dissection of paraspinal muscles in posterior surgical approaches, the spine surgeon usually holds a subperiosteal (Cobb) elevator in 1 hand and a monopolar cautery in the other hand. In such a scenario, both the surgical smoke generated by the monopolar and eventual bleeding constitute a significant hindrance to simultaneous bilateral dissection of the paraspinal muscles by 2 surgeons.

METHODS

To address the identified shortcomings in the currently available instrumentation, we initially analyzed the most common surgical techniques employed by residents and fellows at our institution for paraspinal muscle dissection during posterior spinal approaches. Additionally, we collected trainees' feedback regarding the efficacy of available strategies for dealing with surgical smoke.

RESULTS

A new coupled Cobb elevator-suction instrument was designed, manufactured, and tested by residents, fellows, and experienced spine surgeons, and small additional design modifications were performed.

CONCLUSIONS

We present what we believe is the first description of a new coupled Cobb-suction instrument that has been developed to enable simultaneous retraction and suction with 1 hand, while allowing the spine surgeon to use the monopolar cautery with the other hand. In our preliminary institutional experience, this new tool has been proven to be especially useful in long posterior spinal approaches in the thoracolumbar region.

Rapid Development of Spinal Epidural Lipomatosis after Treatment of Metastatic Castration-Resistant Prostate Cancer with Second-Generation Androgen Receptor Antagonists

BACKGROUND

Previous studies have described the association of spinal epidural lipomatosis with several conditions including chronic steroid therapy, Cushing's syndrome, obesity, Paget disease, and hypothyroidism. We present a report of rapid development of spinal epidural lipomatosis after treatment with second-generation anti-androgen therapy, a new strategy for treatment of metastatic castration-resistant prostate cancer that has been increasingly employed in the past few years. A comprehensive discussion of the underlying molecular networks involving androgen receptor blockage and adipocyte differentiation, as well as the clinical implications of such a phenomenon, are provided.

CASE DESCRIPTION

We describe the clinical and radiological evolution of a 58-year-old male patient with metastatic prostate cancer, who developed new onset of rapidly progressing lumbosacral epidural lipomatosis with significant compression of the nerve roots of the cauda equina a few months after initiation of treatment with second-generation androgen receptor antagonists.

CONCLUSIONS

The underlying pathophysiology of adipose tissue growth following the administration of anti-androgen therapy is discussed, with emphasis on both the canonical Wnt/β-catenin pathway as well as in the Wnt-independent pathway involving direct activation of downstream transcription factors from the T-cell factor family by the androgen receptor. As second-generation androgen receptor antagonists have been increasingly used for treatment of castration-resistant stage metastatic prostate cancer, new onset of symptomatic epidural lipomatosis should be considered as a possible differential diagnosis, especially because the urinary symptoms of cauda equina compression may be improperly attributed to the primary prostate neoplasm.

"Crimes against the Nervous System": Neurological References During the Nuremberg Doctors' Trials

The Nuremberg Trials were a sequence of tribunal sessions held by the Allied Forces between November 1945 and October 1946 with the intent of prosecuting prominent representatives of the Nazi Party for crimes committed before and during the war. Because medical experiments in human prisoners were among the most heinous offenses, a specific series of court cases, known as the Doctor's Trials (the USA vs. Karl Brandt et al), was carried out. A considerable part of the official documents of the Nuremberg Trials has been recently made publicly available through the Nuremberg Trials Project, an initiative of the Harvard Law School Library. We performed a comprehensive analysis of the Doctors' Trials original documents (NMT 1: Medical Case) as well as other available academic and historical sources focusing on references to the nervous system, neurosurgical, and neurologic diseases. Besides providing a brief glance of a unique source of original historical documents, this historical vignette also attempts to fulfill, at least in some limited sense, the moral duty toward the Holocaust victims laid on our generation by remembering their fate.

Clinical Outcomes of Total Disc Replacement Versus Anterior Lumbar Interbody Fusion for Surgical Treatment of Lumbar Degenerative Disc Disease

STUDY DESIGN

The authors performed a retrospective controlled study of patients diagnosed with lumbar degenerative disc disease who received surgical intervention (either total disc replacement [TDR]/Activ-L or anterior lumbar interbody fusion [ALIF]) at a single tertiary-care hospital from 2007-2010.

OBJECTIVES

To investigate the clinical outcomes after TDR in comparison with ALIF for surgical treatment of lumbar degenerative disc disease (DDD).

METHODS

Analyzed data included intra-operative blood loss, time to return to work, and clinical outcomes as evaluated through the Oswestry Disability Index (ODI) and the Visual Analog Scale (VAS) pain questionnaires pre-operatively and at 6 weeks, 3 months, 6 months, and 1 year postoperative follow-up.

RESULTS

At the univariate analysis, patients submitted to TDR presented significantly lower VAS pain scores than patients who received ALIF starting at 6 weeks (P < .001) and continuing through one year postoperatively (P = .007). Patients submitted to TDR also presented significantly lower ODI disability scores at all time points. There was a significant difference in the number of days to return to work, with TDR patients returning to work on average 65 days sooner than ALIF patients (P = .011). There was no significant difference in the total blood loss between both groups.

CONCLUSIONS

The results of this retrospective controlled study suggest that, in comparison with patients submitted to ALIF, patients submitted to TDR present quicker return to work, less back pain, and lower disability scores at 1 year follow-up.

Cavitational kyphoplasty: a new technique for reducing the rates of cement extravasation through targeted low-pressure cement injection

BACKGROUND

Previous studies have demonstrated lower rates of cement extravasation when comparing balloon kyphoplasty with vertebroplasty, an effect attributed to the low-pressure injection. However, in patients with isolated endplate fractures, balloon kyphoplasty may lead to further endplate damage and increased risks of intradiscal extravasation.

METHODS

The author provides a stepwise description of a new technique called cavitational kyphoplasty that allows targeted low-pressure cement injection without the necessity of balloon inflation.

CONCLUSIONS

The new technique of cavitational kyphoplasty has been shown to be specially useful in patients with isolated endplate fractures without significant loss of the vertebral body height.

Effectiveness of Operative and Nonoperative Care for Adult Spinal Deformity: Systematic Review of the Literature

STUDY DESIGN

Systematic review.

OBJECTIVE

There is a need for synthesizing data on effectiveness of treatments for patients with adult spinal deformity (ASD) due to its increasing prevalence and health care costs for these patients. The objective of this review was to estimate the effectiveness of surgery versus nonoperative care in patients with ASD.

METHODS

A systematic review of articles in published in English using PubMed between 2005 and 2015. Surgical and nonsurgical series that reported baseline and follow-up health-related quality of life measures of patients with ASD with a minimum 2 years of follow-up were selected. Independent extraction of articles by 2 authors using predefined data fields, including risk of bias assessment.

RESULTS

Surgery significantly reduces disability, pain, and improves patients' quality of life. The average postoperative improvement in Oswestry Disability Index was -19.1 (±9.0), Numerical Rating Scale back pain -4.14 (±1.38), Numerical Rating Scale leg pain -3.36 (±1.33), Short-Form Health Survey 36-SF36-Physical Component score 11.2 (±5.07), and Short-Form Health Survey 36-Mental Component score 9.93 (±4.96). The complication rate ranged from 9.52% to 81.52% (mean = 39.62%), and the need for revision surgery ranged from 1.72% to 40.0% (mean = 15.71%). The best existing evidence about nonoperative care of ASD is provided from observational studies with very high risk of bias. Quantitative analyses of nonsurgical cohorts did not demonstrate significant changes in quality of life of patients after 2 years of observation.

CONCLUSIONS

This data may assist clinicians to counsel patients, as well as to inform health care providers and policymakers about what to expect from the treatment for ASD.

Vertebral body fracture after anterior cervical discectomy and fusion with zero-profile anchored cages in adjacent levels: a cautionary tale

BACKGROUND CONTEXT

Zero-profile (also called self-locking, anchored or stand-alone cages) have been recently proposed as an interesting alternative for anterior cervical discectomy and fusion (ACDF), as they are supposed to reduce the rates of post-operative cage extrusion without necessarily incurring in the additional surgical time and increased rates of dysphagia associated with plating. Nevertheless, the exact indications of zero-profile anchored cages have not yet been established in the literature.

PURPOSE

To report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels and to review the available literature on hardware-related complications after multi-level ACDFs with zero-profile anchored cages.

STUDY DESIGN

Case report and systematic literature review.

METHODS

The authors report the first case of a vertebral body fracture between the blades of zero-profile anchored cages after ACDFs in adjacent levels. The patient presented with refractory mechanical neck pain at the 1-month post-operative follow-up, ultimately requiring a posterior instrumented fusion. A comprehensive systematic literature review on the available data regarding the safety, complications as well as radiological and clinical outcomes of zero-profile anchored cages is also performed.

RESULTS

In the reported case, the use of zero-profile anchored cages in adjacent levels on the cervical spine led to a fracture of the vertebral body between the cages at the 1-month follow-up, with anterior avulsion of the part of the vertebral body where the blades from the two cages converged. According to the systematic literature review which included 409 patients from 10 different clinical series (with a total cumulative follow-up of approximately 535 patients-year), there were only two reported hardware-related complications after ACDF with zero-profile anchored cages, none of them involving fracture at the level of convergence of blades or screws.

CONCLUSIONS

Although hardware-related complications after the use of zero-profile anchored cages seem to be rare events, future biomechanical and clinical studies are warranted in order to evaluate the safety of employing such devices for the treatment of multilevel degenerative disc disease in the cervical spine.