Tumor markers in non-small cell lung cancer spine metastasis: an assessment of prognosis and overall survival.

PURPOSE: The identification of gene mutations in the modern medical workup of metastatic spine tumors has become more common but has not been highly utilized in surgical planning. Potential utility of these genetic markers as surrogates for cancer behavior in current prognosis scoring systems and overall survival (OS) remains underexplored in existing literature. This study seeks to investigate the association of frequently identified tumor markers, EGFR, ALK, and PD-L1, in metastatic non-small cell lung cancer (NSCLC) to the spine with Tokuhashi prognosis scoring and OS. METHODS: Patients with NSCLC metastasis to spine were identified through chart review. EGFR, ALK, and PD-L1 wild type vs. mutant type were identified from targeted chemotherapy genetic testing. Multiple linear regression was performed to assess gene profile contributions to Tokuhashi score. Cox Proportional Hazards models were generated for each tumor marker to assess the relationship between each marker and OS. RESULTS: A total of 119 patients with NSCLC spine metastasis were identified. We employed a multiple linear regression analysis to investigate the influence of EGFR, ALK, and PD-L1 genotypes on the Tokuhashi score, revealing statistically significant relationships overall (p = 0.002). Individual genotype contributions include EGFR as a non-significant contributor (p = 0.269) and ALK and PD-L1 as significant contributors (p = 0.037 and p = 0.001 respectively). Overall survival was not significantly associated with tumor marker profiles through Kaplan-Meier analysis (p = 0.46) or by multivariable analysis (p = 0.108). CONCLUSION: ALK and PD-L1 were significantly associated with Tokuhashi score while EGFR was not. Tumor markers alone were not predictive of OS. These findings indicate that genetic markers found in NSCLC metastases to the spine may demonstrate prognostic value. Therefore, employing standard tumor markers could enhance the identification of appropriate surgical candidates, although they demonstrate limited effectiveness in predicting overall survival.

Factors associated with adjacent-level tumor progression in patients receiving surgery followed by radiosurgery for metastatic epidural spinal cord compression.

OBJECTIVE: Separation surgery followed by spine stereotactic radiosurgery (SSRS) has been shown to achieve favorable rates of local tumor control and patient-reported outcomes in patients with metastatic epidural spinal cord compression (MESCC). However, rates and factors associated with adjacent-level tumor progression (ALTP) in this population have not yet been characterized. The present study aimed to identify factors associated with ALTP and examine its association with overall survival (OS) in patients receiving surgery followed by radiosurgery for MESCC. METHODS: Thirty-nine patients who underwent separation surgery followed by SSRS for MESCC were identified using a prospectively collected database and were retrospectively reviewed. Radiological measurements were collected from preoperative, postoperative, and post-SSRS MRI. Statistical analysis was conducted using the Kaplan-Meier product-limit method and Cox proportional hazards test. Subgroup analysis was conducted for patients who experienced ALTP into the epidural space (ALTP-E). RESULTS: The authors' cohort included 39 patients with a median OS of 14.7 months (range 2.07-96.3 months). ALTP was observed in 16 patients (41.0%) at a mean of 6.1 ± 5.4 months postradiosurgery, of whom 4 patients (10.3%) experienced ALTP-E. Patients with ALTP had shorter OS (13.0 vs 17.1 months, p = 0.047) compared with those without ALTP. Factors associated with an increased likelihood of ALTP included the amount of bone marrow infiltrated by tumor at the index level, amount of residual epidural disease following separation surgery, and prior receipt of radiotherapy at the index level (p < 0.05). Subgroup analysis revealed that primary tumor type, amount of preoperative epidural disease, time elapsed between surgery and radiosurgery, and prior receipt of radiotherapy at the index level were significantly associated with ALTP-E (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study is the first to identify possible risk factors for ALTP, and they suggest that it may be associated with shorter OS in patients receiving surgery followed by radiosurgery for MESCC. Future studies with higher power should be conducted to further characterize factors associated with ALTP in this population.

Multimodal Analgesic Regimen for Spine Surgery: A Randomized Placebo-controlled Trial.

BACKGROUND: Various multimodal analgesic approaches have been proposed for spine surgery. The authors evaluated the effect of using a combination of four nonopioid analgesics versus placebo on Quality of Recovery, postoperative opioid consumption, and pain scores. METHODS: Adults having multilevel spine surgery who were at high risk for postoperative pain were double-blind randomized to placebos or the combination of single preoperative oral doses of acetaminophen 1,000 mg and gabapentin 600 mg, an infusion of ketamine 5 µg/kg/min throughout surgery, and an infusion of lidocaine 1.5 mg/kg/h intraoperatively and during the initial hour of recovery. Postoperative analgesia included acetaminophen, gabapentin, and opioids. The primary outcome was the Quality of Recovery 15-questionnaire (0 to 150 points, with 15% considered to be a clinically important difference) assessed on the third postoperative day. Secondary outcomes were opioid use in morphine equivalents (with 20% considered to be a clinically important change) and verbal-response pain scores (0 to 10, with a 1-point change considered important) over the initial postoperative 48 h. RESULTS: The trial was stopped early for futility per a priori guidelines. The average duration ± SD of surgery was 5.4 ± 2.1 h. The mean ± SD Quality of Recovery score was 109 ± 25 in the pathway patients (n = 150) versus 109 ± 23 in the placebo group (n = 149); estimated difference in means was 0 (95% CI, -6 to 6, P = 0.920). Pain management within the initial 48 postoperative hours was not superior in analgesic pathway group: 48-h opioid consumption median (Q1, Q3) was 72 (48, 113) mg in the analgesic pathway group and 75 (50, 152) mg in the placebo group, with the difference in medians being -9 (97.5% CI, -23 to 5, P = 0.175) mg. Mean 48-h pain scores were 4.8 ± 1.8 in the analgesic pathway group versus 5.2 ± 1.9 in the placebo group, with the difference in means being -0.4 (97.5% CI; -0.8, 0.1, P = 0.094). CONCLUSIONS: An analgesic pathway based on preoperative acetaminophen and gabapentin, combined with intraoperative infusions of lidocaine and ketamine, did not improve recovery in patients who had multilevel spine surgery.

Development and implementation of a comprehensive spine surgery enhanced recovery after surgery protocol: the Cleveland Clinic experience.

Enhanced recovery after surgery (ERAS) protocols have been shown to be effective at reducing perioperative morbidity and costs while improving outcomes. To date, spine surgery protocols have been limited in scope, focusing only on specific types of procedures or specific parts of the surgical episode. The authors describe the creation and implementation of one of the first comprehensive ERAS protocols for spine surgery. The protocol is unique in that it has a comprehensive perioperative paradigm encompassing the entire surgical period that is tailored based on the complexity of each individual spine patient.

Accuracy of Linking VR-12 and PROMIS Global Health Scores in Clinical Practice.

OBJECTIVES: To examine the accuracy of general health cross-walk tables in a clinical sample of patients with spine disorders. Published tables (Schalet BD, Rothrock NE, Hays RD, et al. Linking physical and mental health summary scores from the Veterans RAND 12-Item Health Survey (VR-12) to the PROMIS(®) Global Health Scale. J Gen Intern Med 2015;30:1524-30) link scores from the Veterans RAND 12-Item Health Survey (VR-12) to the 10-Item Patient-Reported Outcome Measurement Information System (PROMIS), a global health scale metric for both mental (GMH) and physical (GPH) summary scores. METHODS: We assessed the accuracy of administered PROMIS and VR-12 scores with scores predicted by cross-walks in 4606 adult patients seen in a spine clinic from October 2015 to 2016. Accuracy of linking scores was evaluated using Pearson correlation, intraclass correlation coefficients, and mean and SD of score differences. Bland-Altman plots were used to graphically assess the levels of agreement. The consistency in scores' discrimination across levels of pain severity, depression, and other patient characteristics was assessed. Bootstrap methods estimated linking precision across varying sample sizes. RESULTS: Actual and cross-walked PROMIS scores showed moderate correlation (ICC(3,1): GMH 0.73; GPH 0.81), with Bland-Altman plots suggesting smaller differences between scores in patients with lower and higher general health. Significant discrimination between patient subgroups was demonstrated reliably by both actual and estimated scores. Bootstrapped resamples indicated adequate precision for 200 patients (95% confidence interval for mean difference: GMH -1.38 to 0.60; GPH 0.39 to 1.93). CONCLUSIONS: VR-12 and PROMIS global health scores can be accurately linked within a sample of patients with spine disorders; nevertheless, bias is high and precision is low for linking on the patient level. Linked scores at the group level for more than 200 patients can be used in comparative effectiveness research and for comparing results across studies.

Complications and Outcomes for Surgical Approaches to Cervical Kyphosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The primary objective of this study is to report the safety and efficacy of the different surgical approaches to cervical deformity correction surgery. SUMMARY OF BACKGROUND DATA: Cervical subaxial deformity surgery has been shown to be an effective means to alleviate pain and improve neurological function in symptomatic patients. The reported outcomes and complications for the different surgical approaches (ventral, dorsal, and combined) are limited to small retrospective studies. The appropriate surgical approach is at times unclear, which is likely attributed to the overlap in indications for the ventral and combined approach. MATERIALS AND METHODS: A retrospective review of 76 patients who underwent cervical deformity surgery for cervical kyphosis at 1 institution was performed. The authors reviewed the complications, radiographic outcomes, and long-term functional outcomes for all patients. RESULTS: The majority of patients in all groups reported excellent (15%) or good (50%) outcomes, with a mean improvement in modified Japanese orthopedic association score of 1.3. There were 26 perioperative complications (34%) for 19 patients (25%). We found the ventral-alone and combined approaches to achieve similar degrees of correction (23.1 and 23.2 degrees, respectively). The combined approach had the highest complication rate of the 3 approaches (combined: 40%, ventral: 30%, dorsal: 27%). The dorsal, ventral, and combined approaches had a mean neurological improvement in modified Japanese orthopedic association scores of 1.95, 3.00, and 1.26, respectively, and mean pain improvement of 0.8, 2.0, and 1.4. CONCLUSIONS: Given the moderate improvements in long-term outcomes, and the risks for perioperative complications, we recommend a careful selection process for patients eligible for cervical deformity surgery. We found that the ventral approach has reduced complications, similar degree of correction capability, and potentially higher improved neurological outcomes compared to the combined approach.

The Use of Cranial Aneurysm Clips for Repair of Incidental Lumbar Durotomy: Operative Technique and Case Series.

BACKGROUND: Incidental durotomy is a common complication of posterior lumbar spine surgery; however, effective and durable methods for primary repair remain elusive. Multiple existing techniques have previously been reported and extensively described, including sutured repair and the use of nonpenetrating titanium clips. The use of cranial aneurysm clips for primary repair of lumbar durotomy serves as a safe and effective alternative to obtain watertight closure of a dural tear. METHODS: We performed a retrospective review of patients at a single institution who underwent primary repair of an incidental lumbar durotomy with the use of an aneurysm clip during open posterior lumbar surgery between 2012 and 2023. Patient demographics, operative details, and postoperative metrics were collected and examined to evaluate the safety and efficacy of the novel technique. RESULTS: A total of 51 patients were included for analysis. Four patients underwent durotomy repair with an aneurysm clip alone, 27 patients were repaired with an aneurysm clip and fibrin glue, and 20 patients underwent repair with an aneurysm clip, fibrin glue, and a collagen dural substitute. Three patients (5.9%) reported headaches: 2 (3.9%) with pseudomeningocele and 1 (2%) with wound leakage. Two patients (3.9%) had treatment failure with a return to the operating room for repair of a cerebrospinal fluid leak. CONCLUSIONS: To the best of our knowledge, we report the largest series of patients undergoing primary repair of incidental durotomy with the use of an aneurysm clip. Use of an aneurysm clip is noted to be a safe, quick, and effective method of primary repair compared with existing repair techniques such as sutured repair or nonpenetrating titanium clips.

Effective and Successful Control of Symptomatic Vertebral Hemangiomas With Epidural Extension Using Stereotactic Spine Radiosurgery.

BACKGROUND AND OBJECTIVES: We present our experience in the management of symptomatic vertebral hemangiomas with epidural extension (SVHEE) using spine stereotactic radiosurgery (SSRS). METHODS: An Institutional Review Board approved retrospective review of all SVHEE patients treated with SSRS at our institution (2007-2022) was performed. Baseline patient demographics, clinical presentation, lesion volume, and Bilsky grade (to directly evaluate the epidural component) were determined. Clinical and radiographic response and treatment outcomes were subsequently evaluated at first (∼6 months) and final follow-up. RESULTS: Fourteen patients with SVHEE underwent SSRS (16-18 Gy/1-fraction); the mean follow-up was 24 months. The median lesion volume (cc) was 36.9 (range: 7.02-94.1), 31.5 (range: 6.53-69.7), and 25.15 (range: 6.01-52.5) at pre-SSRS, first, and final follow-up, respectively. Overall volume reduction was seen in the last follow-up in all 14 patients, median 29.01% (range: 6.58%-71.58%). Bilsky score was stable or improved in all patients at the last follow-up when compared with pre-SSRS score. Patients who underwent both surgical decompression and SSRS (n = 9): 8 had improved myelopathic symptoms and pain and 1 had stable radiculopathy postintervention. In the 5 patients treated with SSRS monotherapy, 2 had stable radicular pain and the other 3 improved pain and numbness. No patients experienced adverse outcomes. CONCLUSION: To our knowledge, this represents the largest series of SVHEE patients treated with SSRS, either as monotherapy or part of a multimodal/separation surgery treatment approach. We demonstrate that SSRS represents a potentially safe and effective treatment option in these patients. However, larger prospective studies and longer follow-ups are necessary to further assess the role, durability, and toxicity of SSRS in the management of these patients.

Exploring tribology and material contact science in spine surgery: implications for implant design.

Tribology, an interdisciplinary field concerned with the science of interactions between surfaces in contact and their relative motion, plays a well-established role in the design of orthopedic implants, such as knee and hip replacements. However, its applications in spine surgery have received comparatively less attention in the literature. Understanding tribology is pivotal in elucidating the intricate interactions between metal, polymer, and ceramic components, as well as their interplay with the native human bone. Numerous studies have demonstrated that optimizing tribological factors is key to enhancing the longevity of joints and implants while simultaneously reducing complications and the need for revision surgeries in both arthroplasty and spinal fusion procedures. With an ever-growing and diverse array of spinal implant devices hitting the market for static and dynamic stabilization of the spine, it is important to consider how each of these devices optimizes these parameters and what factors may be inadequately addressed by currently available technology and methods. In this comprehensive review, the authors' objectives were twofold: 1) delineate the unique challenges encountered in spine surgery that could be addressed through optimization of tribological parameters; and 2) summarize current innovations and products within spine surgery that look to optimize tribological parameters and highlight new avenues for implant design and research.

Preparing Residents to Navigate Neurosurgical Careers in the 21st Century: Implementation of a Yearlong Enhanced Didactics Curriculum.

BACKGROUND AND OBJECTIVE: Neurosurgery residency, known for its rigorous training, must adapt to evolving healthcare demands. Formal education should now encompass areas like quality improvement and patient safety (QIPS), machine learning, career planning, research infrastructure, grant funding, and socioeconomics. We share our institution's experience with a yearlong enhanced didactics curriculum, complementing our traditional teaching. METHODS: Our resident and faculty team evaluated essential skills for trainee success and leadership, identified knowledge gaps, and addressed them with 31 lectures. We conducted pre- and 6-month surveys using a Likert scale (1 = strongly disagree, 3 = neutral, 5 = strongly agree) to assess resident education. Survey results were analyzed using Student t-tests, with p < 0.05 indicating statistical significance. RESULTS: Eleven out of twelve residents completed the pre- and 6-month surveys. The surveys revealed improved scores in areas such as research career preparation (3.0/5 to 4.33/5, p=0.002), building research skills (3.18/5 to 4.33/5, p=0.002), and comfort with quality and patient safety (4.09/5 to 4.75, p=0.04). Residents found the lectures highly effective in supplementing their residency training (4.58/5). Qualitative feedback from faculty was highly positive as well. CONCLUSIONS: Organized neurosurgery excels in clinical and technical training for residents but lacks formalized training in crucial nonclinical areas, such as QIPS, machine learning/artificial intelligence, research infrastructure, and socioeconomics. Our formal curriculum focused on these topics, with positive resident engagement and feedback over the first six months. However, continuous longitudinal monitoring is needed to confirm the curriculum's efficacy. This program may guide other neurosurgery departments in enhancing resident education in these areas.

Risk assessment of early therapeutic anticoagulation following cranial surgery: an institutional case series.

OBJECTIVE: Postoperative thrombotic complications represent a unique challenge in cranial neurosurgery as primary treatment involves therapeutic anticoagulation. The decision to initiate therapy and its timing is nuanced, as surgeons must balance the risk of catastrophic intracranial hemorrhage (ICH). With limited existing evidence to guide management, current practice patterns are subjective and inconsistent. The authors assessed their experience with early therapeutic anticoagulation (≤ 7 days postoperatively) initiation for thrombotic complications in neurosurgical patients undergoing cranial surgery to better understand the risks of catastrophic ICH. METHODS: Adult patients treated with early therapeutic anticoagulation following cranial surgery were considered. Anticoagulation indications were restricted to thrombotic or thromboembolic complications. Records were retrospectively reviewed for demographics, surgical details, and anticoagulation therapy start. The primary outcome was the incidence of catastrophic ICH, defined as ICH resulting in reoperation or death within 30 days of anticoagulation initiation. As a secondary outcome, post-anticoagulation cranial imaging was reviewed for new or worsening acute blood products. Fisher's exact and Wilcoxon rank-sum tests were used to compare cohorts. Cumulative outcome analyses were performed for primary and secondary outcomes according to anticoagulation start time. RESULTS: Seventy-one patients satisfied the inclusion criteria. Anticoagulation commenced on mean postoperative day (POD) 4.3 (SD 2.2). Catastrophic ICH was observed in 7 patients (9.9%) and was associated with earlier anticoagulation initiation (p = 0.02). Of patients with catastrophic ICH, 6 (85.7%) had intra-axial exploration during their index surgery. Patients with intra-axial exploration were more likely to experience a catastrophic ICH postoperatively compared to those with extra-axial exploration alone (OR 8.5, p = 0.04). Of the 58 patients with postoperative imaging, 15 (25.9%) experienced new or worsening blood products. Catastrophic ICH was 9 times more likely with anticoagulation initiation within 48 hours of surgery (OR 8.9, p = 0.01). The cumulative catastrophic ICH risk decreased with delay in initiation of anticoagulation, from 21.1% on POD 2 to 9.9% on POD 7. Concurrent antiplatelet medication was not associated with either outcome measure. CONCLUSIONS: The incidence of catastrophic ICH was significantly increased when anticoagulation was initiated within 48 hours of cranial surgery. Patients undergoing intra-axial exploration during their index surgery were at higher risk of a catastrophic ICH.

Treatment of intramedullary spinal cord tumors: a modified Delphi technique of the North American Spine Society Section of Spine Oncology.

OBJECTIVE: Intramedullary spinal cord tumors (IMSCTs) are rare tumors with heterogeneous presentations and natural histories that complicate their management. Standardized guidelines are lacking on when to surgically intervene and the appropriate aggressiveness of resection, especially given the risk of new neurological deficits following resection of infiltrative tumors. Here, the authors present the results of a modified Delphi method using input from surgeons experienced with IMSCT removal to construct a framework for the operative management of IMSCTs based on the clinical, radiographic, and tumor-specific characteristics. METHODS: A modified Delphi technique was conducted using a group of 14 neurosurgeons experienced in IMSCT resection. Three rounds of written correspondence, surveys, and videoconferencing were carried out. Participants were queried about clinical and radiographic criteria used to determine operative candidacy and guide decision-making. Members then completed a final survey indicating their choice of observation or surgery, choice of resection strategy, and decision to perform duraplasty, in response to a set of patient- and tumor-specific characteristics. Consensus was defined as ≥ 80% agreement, while responses with 70%-79% agreement were defined as agreement. RESULTS: Thirty-six total characteristics were assessed. There was consensus favoring surgical intervention for patients with new-onset myelopathy (86% agreement), chronic myelopathy (86%), or progression from mild to disabling numbness (86%), but disagreement for patients with mild numbness or chronic paraplegia. Age was not a determinant of operative candidacy except among frail patients, who were deemed more suitable for observation (93%). Well-circumscribed (93%) or posteriorly located tumors reaching the surface (86%) were consensus surgical lesions, and participants agreed that the presence of syringomyelia (71%) and peritumoral T2 signal change (79%) were favorable indications for surgery. There was consensus that complete loss of transcranial motor evoked potentials with a 50% decrease in the D-wave amplitude should halt further resection (93%). Preoperative symptoms seldom influenced choice of resection strategy, while a distinct cleavage plane (100%) or visible tumor-cord margins (100%) strongly favored gross-total resection. CONCLUSIONS: The authors present a modified Delphi technique highlighting areas of consensus and agreement regarding surgical management of IMSCTs. Although not intended as a substitute for individual clinical decision-making, the results can help guide care of these patients. Additionally, areas of controversy meriting further investigation are highlighted.

Transcervical, retropharyngeal odontoidectomy - Anatomical considerations.

Context: Anterior craniocervical junction lesions have always been a challenge for neurosurgeons. Presenting with lower cranial nerve dysfunction and symptoms of brainstem compression, decompression is often required. While posterior approaches offer indirect ventral brainstem decompression, direct decompression via odontoidectomy is necessary when they fail. The transoral and endoscopic endonasal approaches have been explored but come with their own limitations and risks. A novel retropharyngeal approach to the cervical spine has shown promising results with reduced complications. Aims: This study aims to explore the feasibility and potential advantages of the anterior retropharyngeal approach for accessing the odontoid process. Methods and Surgical Technique: To investigate the anatomical aspects of the anterior retropharyngeal approach, a paramedian skin incision was performed below the submandibular gland on two cadaveric specimens. The subcutaneous tissue followed by the platysma is dissected, and the superficial fascial layer is opened. The plane between the vascular sheath laterally and the pharyngeal structures medially is entered below the branching point of the facial vein and internal jugular vein. After reaching the prevertebral plane, further dissection cranially is done in a blunt fashion below the superior pharyngeal nerve and artery. Various anatomical aspects were highlighted during this approach. Results: The anterior, submandibular retropharyngeal approach to the cervical spine was performed successfully on two cadavers highlighting relevant anatomical structures, including the carotid artery and the glossopharyngeal, hypoglossal, and vagus nerves. This approach offered wide exposure, avoidance of oropharyngeal contamination, and potential benefit in repairing cerebrospinal fluid fistulas. Conclusions: For accessing the craniocervical junction, the anterior retropharyngeal approach is a viable technique that offers many advantages. However, when employing this approach, surgeons must have adequate anatomical knowledge and technical proficiency to ensure better outcomes. Further studies are needed to enhance our anatomical variations understanding and reduce intraoperative risks.

Characterizing the Next Generation of Neurosurgeons: A Descriptive Analysis and Publicly Available Web Application of Neurosurgery Residency Programs' Website Data.

OBJECTIVE: Neurosurgery program websites serve as a valuable resource for applicants. However, each website exists in isolation, and it can be difficult to understand the general trends in U.S. neurosurgery resident demographics. In the present study, we collected data from program websites and analyzed the trends in the demographics of the current U.S. neurosurgery residents. METHODS: We used a program list obtained from the American Association of Medical Colleges Electronic Residency Application System to extract data from the current resident complement listed in each program's website, including program, year in program, medical school, sex (male vs. female), graduate and/or PhD degrees, and assessed the trends during 7 years of resident data using linear regression. RESULTS: We identified 116 neurosurgery residency programs in the United States, with 111 providing information on their current resident complement, yielding a dataset of 1599 residents. Of these 1599 residents, 348 (22%) were female, 301 (19%) had a graduate degree in addition to an MD or DO degree, 151 (9.4%) had a PhD degree, 300 (19%) had matched at the program affiliated with their medical school, and 121 (7.6%) had graduated from a foreign medical school. The proportion of matriculating female residents had increased an average of 2.1% annually (95% confidence interval, 0.6%-3.7%) from 2015 to 2021. The other demographic data had not changed significantly during the same period. CONCLUSIONS: In addition to summarizing the current resident demographics, our analysis identified a significant increase in the proportion of female residents between 2015 (15.1%) and 2021 (25.6%). This publicly available dataset should enable additional analyses of the evolution of neurosurgery resident demographics.

Metastatic Breast Cancer to the Spine: Incidence of Somatic Gene Alterations and Association of Targeted Therapies With Overall Survival.

BACKGROUND: The increase in use of targeted systemic therapies in cancer treatments has catalyzed the importance of identifying patient- and tumor-specific somatic mutations, especially regarding metastatic disease. Mutations found to be most prevalent in patients with metastatic breast cancer include TP53, PI3K, and CDH1. OBJECTIVE: To determine the incidence of somatic mutations in patients with metastatic breast cancer to the spine (MBCS). To determine if a difference exists in overall survival (OS), progression-free survival, and progression of motor symptoms between patients who do or do not undergo targeted systemic therapy after treatment for MBCS. METHODS: This is a retrospective study of patients with MBCS. Review of gene sequencing reports was conducted to calculate the prevalence of various somatic gene mutations within this population. Those patients who then underwent treatment (surgery/radiation) for their diagnosis of MBCS between 2010 and 2020 were subcategorized. The use of targeted systemic therapy in the post-treatment period was identified, and post-treatment OS, progression-free survival, and progression of motor deficits were calculated for this subpopulation. RESULTS: A total of 131 patients were included in the final analysis with 56% of patients found to have a PI3K mutation. Patients who received targeted systemic therapies were found to have a significantly longer OS compared with those who did not receive targeted systemic therapies. CONCLUSION: The results of this study demonstrate that there is an increased prevalence of PI3K mutations in patients with MBCS and there are a significant survival benefit and delay in progression of motor symptoms associated with using targeted systemic therapies for adjuvant treatment.

Prospective, randomized controlled multicenter study of posterior lumbar facet arthroplasty for the treatment of spondylolisthesis.

OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of a posterior facet replacement device, the Total Posterior Spine (TOPS) System, for the treatment of one-level symptomatic lumbar stenosis with grade I degenerative spondylolisthesis. Posterior lumbar arthroplasty with facet replacement is a motion-preserving alternative to lumbar decompression and fusion. The authors report the preliminary results from the TOPS FDA investigational device exemption (IDE) trial. METHODS: The study was a prospective, randomized controlled FDA IDE trial comparing the investigational TOPS device with transforaminal lumbar interbody fusion (TLIF) and pedicle screw fixation. The minimum follow-up duration was 24 months. Validated patient-reported outcome measures included the Oswestry Disability Index (ODI) and visual analog scale (VAS) for back and leg pain. The primary outcome was a composite measure of clinical success: 1) no reoperations, 2) no device breakage, 3) ODI reduction of ≥ 15 points, and 4) no new or worsening neurological deficit. Patients were considered a clinical success only if they met all four measures. Radiographic assessments were made by an independent core laboratory. RESULTS: A total of 249 patients were evaluated (n = 170 in the TOPS group and n = 79 in the TLIF group). There were no statistically significant differences between implanted levels (L4-5: TOPS, 95% and TLIF, 95%) or blood loss. The overall composite measure for clinical success was statistically significantly higher in the TOPS group (85%) compared with the TLIF group (64%) (p = 0.0138). The percentage of patients reporting a minimum 15-point improvement in ODI showed a statistically significant difference (p = 0.037) favoring TOPS (93%) over TLIF (81%). There was no statistically significant difference between groups in the percentage of patients reporting a minimum 20-point improvement on VAS back pain (TOPS, 87%; TLIF, 64%) and leg pain (TOPS, 90%; TLIF, 88%) scores. The rate of surgical reintervention for facet replacement in the TOPS group (5.9%) was lower than the TLIF group (8.8%). The TOPS cohort demonstrated maintenance of flexion/extension range of motion from preoperatively (3.85°) to 24 months (3.86°). CONCLUSIONS: This study demonstrates that posterior lumbar decompression and dynamic stabilization with the TOPS device is safe and efficacious in the treatment of lumbar stenosis with degenerative spondylolisthesis. Additionally, decompression and dynamic stabilization with the TOPS device maintains segmental motion.

Incorporation of Blood and Fluid Management Within an Enhanced Recovery after Surgery Protocol in Complex Spine Surgery.

STUDY DESIGN: retrospective review. OBJECTIVE: Enhanced Recovery After Surgery (ERAS) is a multidisciplinary set of evidence-based interventions to reduce morbidity and accelerate postoperative recovery. Complex spine surgery carries high risks of perioperative blood loss, blood transfusion, and suboptimal fluid states. This study evaluates the efficacy of a perioperative fluid and blood management component comprised of a restrictive transfusion policy, goal directed fluid management, number of tranexamic acid (TXA) utilization, and autologous blood transfusion within our ERAS protocol for complex spine surgery. METHODS: A retrospective review compared patients undergoing elective complex spine surgery prior to and following implementation of an ERAS protocol with intraoperative blood and fluid management. Outcomes included incidence of blood transfusion, estimated blood loss, intraoperative crystalloids administered, frequency of intraoperative TXA utilized, incidence of patients extubated within the operating room (OR), intensive care unit (ICU) admission, and hospital length of stay. RESULTS: Following implementation, the rate of blood transfusion decreased by 11.7%(P = .017) and average crystalloid infusion was reduced 680 mL per case(P < .001). Intraoperative blood loss decreased on average 342 mL per case(P = .001) and TXA use increased significantly by 25%(P < .001). Postoperative ICU admissions declined by 8.5%(P = .071); extubation within the OR increased by 13.3%(P = .005). CONCLUSIONS: This protocol presents a unique perspective with the inclusion of an interdisciplinary and comprehensive blood and fluid management protocol as an integral part of our ERAS pathway for complex spine surgery. These results indicate that a standardized approach is associated with reduced rates of blood transfusion and optimized fluid states which was correlated with decreased postoperative ICU admissions.

Opioid Alternatives in Spine Surgery: A Narrative Review.

Adequate analgesia is known to improve outcomes after spine surgery. Despite recent attention highlighting the negative effects of narcotics and their addiction potential, opioids have been the mainstay of management for providing analgesia following spine surgeries. However, side effects including hyperalgesia, tolerance, and subsequent dependence restrict the generous usage of opioids. Multimodal analgesia regimens acting through different mechanisms offer significant opioid sparing and minimize the side effects of individual drugs. Hence, they are being increasingly incorporated into enhanced recovery protocols. Multimodal analgesia includes drugs such as N-methyl-D-aspartate antagonists, nonsteroidal anti-inflammatory drugs and membrane-stabilizing agents, neuraxial opioids, local anesthetic infiltration, and fascial compartment blocks. Analgesia started before the painful stimulus, termed preemptive analgesia, facilitates subsequent pain management. Both nonsteroidal anti-inflammatory drugs and neuraxial analgesia have been conclusively shown to reduce opioid requirements after spine surgery, and there is a resurgence of interest in the use of low-dose ketamine or methadone. Neuraxial narcotics offer enhanced analgesia for a longer duration with lower dosage and side effect profiles compared with systemic opioid administration. Fascial compartment blocks are increasingly used as they provide effective analgesia with fewer adverse effects. In this narrative review, we will discuss multimodality analgesic regimens incorporating opioid-sparing adjuvants to manage pain after spine surgery.

Primary Paraganglioma of the Spine: A Systematic Review of Clinical Features and Surgical Management in Cauda Equina versus Non-Cauda Equina Lesions.

BACKGROUND: Primary spine paragangliomas are rare tumors. Surgical resection plays a role, but aggressive lesions are challenging. We reviewed the literature on primary spine paragangliomas. METHODS: PubMed, Scopus, Web of Science, and Cochrane were searched following the PRISMA guidelines to include studies on primary spine paragangliomas. Clinical-radiologic features, treatments, and outcomes were analyzed and compared between cauda equina versus non-cauda equina tumors. RESULTS: We included 143 studies comprising 334 patients. Median age was 46 years (range, 6-85 years). The most frequent symptoms were lower back (64.1%) and radicular (53.9%) pain, and sympathetic in 18 patients (5.4%). Cauda equina paragangliomas (84.1%) had frequently lumbar (49.1%) or lumbosacral (29%) locations. Non-cauda equina tumors were mostly in the thoracic (11.4%), thoracolumbar (5.1%), and cervical (3.6%) spine. Median tumor diameter was 2.5 cm (range, 0.5-13.0 cm). Surgical resection (98.5%) was preferred over biopsy (1.5%). Decompressive laminectomy (53%) and spine fusion (6.9%) were also performed. Adjuvant radiotherapy was delivered in 39 patients (11.7%) with aggressive tumors. Posttreatment symptomatic improvement was described in 86.2% cases. Median follow-up was 19.5 months (range, 0.1-468.0 months), and 23 patients (3.9%) had tumor recurrences. No significant differences were found between cauda equina versus non-cauda equina tumors. CONCLUSIONS: Surgical resection is effective and safe in treating primary spine paragangliomas; however, adjuvant treatments may be needed for aggressive lesions.