Risk of Subsequent Fusion After Isolated Decompression of Lumbar Facet Cysts.

INTRODUCTION: Lumbar facet cysts represent a potential source of nerve root compression in elderly patients. Isolated decompression without fusion has proven to be a reasonable treatment option in properly indicated patients. However, the risk of lumbar fusion after isolated decompression and facet cyst excision has yet to be elucidated. METHODS: The PearlDiver database was reviewed for patients undergoing isolated laminectomy for lumbar facet cyst from January 2015 to December 2018 using Current Procedural Terminology coding. Patients undergoing concomitant fusion or additional decompression, as well as those diagnosed with preexisting spondylolisthesis or without a minimum of 5-year follow-up, were excluded. Rates of subsequent lumbar fusion and potential risk factors for subsequent fusion were identified. Statistical analysis included descriptive statistics, chi square test, and multivariate logistic regression. Results were considered significant at P < 0.05. RESULTS: In total, 10,707 patients were ultimately included for analysis. At 5-year follow-up, 727 (6.79%) of patients underwent subsequent lumbar fusion after initial isolated decompression. Of these, 301 (2.81% of total patients, 41.4% of fusion patients) underwent fusion within the first year after decompression. Multivariate analysis identified chronic kidney disease, hypertension, and osteoarthritis as risk factors for requiring subsequent lumbar fusion at 5 years following the index decompression procedure ( P < 0.033; all). CONCLUSION: Patients undergoing isolated decompression for lumbar facet cysts undergo subsequent lumbar fusion at a 5-year rate of 6.79%. Risk factors for subsequent decompression include chronic kidney disease, hypertension, and osteoarthritis. This study will assist spine surgeons in appropriately counseling patients on expected postoperative course and potential risks of isolated decompression.

The Effect of Intraoperative Prone Position on Psoas Morphology and Great Vessel Anatomy: Consequences for Prone Lateral Approach to the Lumbar Spine.

BACKGROUND: This study sought to quantify radiographic differences in psoas morphology, great vessel anatomy, and lumbar lordosis between supine and prone intraoperative positioning to optimize surgical planning and minimize the risk of neurovascular injury. METHODS: Measurements on supine magnetic resonance imaging and prone intraoperative computed tomography with O-arm from L2 to L5 levels included the anteroposterior and mediolateral proximity of the psoas, aorta, inferior vena cava (IVC), and anterior iliac vessels to the vertebral body. Psoas transverse and longitudinal diameters, psoas cross-sectional area, total lumbar lordosis, and segmental lordosis were assessed. RESULTS: Prone position produced significant psoas lateralization, especially at more caudal levels (P < 0.001). The psoas drifted slightly anteriorly when prone, which was non-significant, but the magnitude of anterior translation significantly decreased at more caudal segments (P = 0.038) and was lowest at L5 where in fact posterior retraction was observed (P = 0.032). When prone, the IVC (P < 0.001) and right iliac vein (P = 0.005) migrated significantly anteriorly, however decreased anterior displacement was seen at more caudal levels (P < 0.001). Additionally, the IVC drifted significantly laterally at L5 (P = 0.009). Mean segmental lordosis significantly increased when prone (P < 0.001). CONCLUSION: Relative to the vertebral body, the psoas demonstrated substantial lateral mobility when prone, and posterior retraction specifically at L5. IVC and right iliac vein experienced significant anterior mobility-particularly at more cephalad levels. Prone position enhanced segmental lordosis and may be critical to optimizing sagittal restoration.

Medicare procedural costs in ambulatory surgery centers versus hospital outpatient departments for spine surgeries.

OBJECTIVE: Multiple studies have demonstrated the safety of outpatient spine surgery, with reports of equivalent to improved patient outcomes compared with inpatient procedures. This has resulted in the increased use of outpatient surgery over time. However, there remains a paucity of literature evaluating the difference in costs between ambulatory surgery center (ASC)- and hospital outpatient department (HOPD)-based procedures for Medicare beneficiaries. METHODS: Publicly available data from Centers for Medicare & Medicaid Services were accessed via the Medicare Procedure Price Lookup tool. Current Procedural Terminology (CPT) codes were used to identify spine-specific procedures approved for the outpatient setting by CMS. Procedures were grouped into decompression (cervical, thoracic, and lumbar), fusion/instrumentation (cervical, lumbar, and sacroiliac), and kyphoplasty/vertebroplasty cohorts, as well as an overall cohort. Data regarding total costs, facility fees, surgeon reimbursement, Medicare payments, and patient copayments were extracted for each procedure. Descriptive statistics were used to calculate means and standard deviations. Differences between ASC- and HOPD-associated costs were analyzed using the Mann-Whitney U-test. RESULTS: Twenty-one individual CPT codes approved by Medicare for the ASC and/or HOPD setting were identified. Decompression procedures were associated with a significantly lower total cost ($4183 ± $411.07 vs $7583.67 ± $410.89, p < 0.001), facility fees ($2998 ± $0 vs $6397 ± $0, p < 0.001), Medicare payments ($3345.75 ± $328.80 vs $6064.75 ± $328.80, p < 0.001), and patient payments ($835.58 ± $82.13 vs $1515.58 ± $82.13, p < 0.001) in ASCs compared with HOPDs. Fusion/instrumentation procedures had significantly lower facility fees ($10,436.6 ± $2347.51 vs $14,161 ± $2147.07, p = 0.044) and Medicare payments ($9501.2 ± $1732.42 vs $13,757 ± $2037.58, p = 0.009) in ASCs, as well as a trend toward lower total costs ($11,876.8 ± $2165.22 vs $15,601.2 ± $2016.06, p = 0.076). Patient payments in the HOPD setting were significantly lower in the fusion/instrumentation cohort ($1843.6 ± $73.42 vs $2374.4 ± $433.48, p = 0.009). In the kyphoplasty/vertebroplasty cohort, there was no statistically significant difference between ASCs and HOPDs, despite lower overall costs in the ASC for all variables. Surgeon fees were the same regardless of setting for all procedures (p > 0.99). When combining decompression, fusion/instrumentation, and kyphoplasty/vertebroplasty CPT codes into a single cohort, ASC setting was associated with significant cost savings in total cost, facility fees, Medicare payments, and patient payments. CONCLUSIONS: In general, performing spine surgeries in ASCs is associated with cost savings compared with HOPDs. This was demonstrated for decompression and fusion/instrumentation, and kyphoplasty/vertebroplasty Medicare-approved outpatient procedures.

Radiolucent implants in orthopedic oncology.

Radiolucent implants in have demonstrated promising results for both extremity and spine oncologic procedures. However, questions persist about whether the superiority in surveillance imaging justify the increased cost and technical challenges. In this review, we present the current body of literature for the use of radiolucent implants in musculoskeletal oncology, with a focus on implant complications, including screw loosening, breakage, malposition, and loss of reduction. We also discuss clinical outcomes, technical considerations, and postoperative radiotherapy.

Postoperative Spinal Hematoma and Seroma.

Fluid collections after spine surgery are rare complications, although potentially grave, and may be broadly grouped into two major categories. Symptomatic postoperative epidural hematomas have some known risk factors and can present with a widely variable profile of signs and symptoms. Treatment involves emergent surgical evacuation to reduce the risk of permanent neurologic deficit. Postoperative seroma may lead to disruption of wound healing and deep infection and has been associated with the use of recombinant human bone mineral protein. These diagnoses may present diagnostic challenges; thorough understanding of the involved pathophysiology, meticulous clinical evaluation, and radiographic interpretation are critical to appropriate management and optimal outcome.

Porous Polyetheretherketone Interbody Cages for Anterior Cervical Discectomy and Fusion at 3 or More Levels: Clinical and Radiographic Outcomes.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) at 3 or more levels remains challenging, with reported high pseudarthrosis rates and implant-related complications. Porous surface polyetheretherketone (PEEK) interbody cages are newer implants for ACDF with limited data available for their use in ACDF procedures at 3 or more levels. The objective of this study was to assess the clinical and radiographic outcomes of porous PEEK devices for ACDF at 3 or more levels. STUDY DESIGN: Retrospective case series. METHODS: Consecutive patients who underwent primary ACDF for degenerative cervical disc disease at 3 or more levels with porous PEEK cages with anterior plate instrumentation were included. Clinical outcome scores, radiographic parameters, pseudarthrosis rates, and cage subsidence rates were assessed. Preoperative and postoperative clinical outcomes and radiographic measures were compared using paired t tests. RESULTS: A total of 33 patients with ACDF at 3 or more levels with porous PEEK cages were included, with minimum 1-year follow-up. Two patients had cage subsidence (6.1%), and 1 patient had pseudarthrosis (3.0%). There were significant postoperative increases in overall cervical lordosis, sagittal vertical axis, fusion segment lordosis, T1 slope, and disc height. Clinical outcomes showed significant improvement from the preoperative visit to the final postoperative follow-up. CONCLUSIONS: High rates of fusion (97.0%) were observed in this challenging patient cohort, which compares favorably with previously published rates of fusion in ACDF at 3 or more levels. CLINICAL RELEVANCE: The optimal management of cervical spinal pathology regarding approach, technique, and implants used is an active area of ongoing investigation. The high levels of radiographic and clinical success utilizing a relatively novel implant material in a high-risk surgical cohort reported here may influence surgical decision making.

Augmented reality in minimally invasive spine surgery: early efficiency and complications of percutaneous pedicle screw instrumentation.

BACKGROUND CONTEXT: Augmented reality (AR) employs an optical projection directly onto the user's retina, allowing complex image overlay on the natural visual field. In general, pedicle screw accuracy rates have improved with increasingly use of technology, with navigation-based instrumentation described as accurate in 89%-100% of cases. Emerging AR technology in spine surgery builds upon current spinal navigation to provide 3-dimensional imaging of the spine and powerfully reduce the impact of inherent ergonomic and efficiency difficulties. PURPOSE: This publication describes the first known series of in vivo pedicle screws placed percutaneously using AR technology for MIS applications. STUDY DESIGN / SETTING: After IRB approval, 3 senior surgeons at 2 institutions contributed cases from June, 2020 - March, 2022. 164 total MIS cases in which AR used for placement of percutaneous pedicle screw instrumentation with spinal navigation were identified prospectively. PATIENT SAMPLE: 155 (94.5%) were performed for degenerative pathology, 6 (3.6%) for tumor and 3 (1.8%) for spinal deformity.  These cases amounted to a total of 606 pedicle screws; 590 (97.3%) were placed in the lumbar spine, with 16 (2.7%) thoracic screws placed. OUTCOME MEASURES: Patient demographics and surgical metrics including total posterior construct time (defined as time elapsed from preincision instrument registration to final screw placement), clinical complications and instrumentation revision rates were recorded in a secure and de-identified database. METHODS: The AR system used features a wireless headset with transparent near-eye display which projects intra-operative 3D imaging directly onto the surgeon's retina. After patient positioning, 1 percuntaneous and 1 superficial reference marker are placed. Intra-operative CT data is processed to the headset and integrates into the surgeon's visual field creating a "see-through" 3D effect in addition to 2D standard navigation images. MIS pedicle screw placement is then carried out percutaneously through single line of sight using navigated instruments. RESULTS: Time elapsed from registration and percutaneous approach to final screw placement averaged 3 minutes and 54 seconds per screw.  Analysis of the learning curve revealed similar surgical times in the early cases compared to the cases performed with more experience with the system.  No instrumentation was revised for clinical or radiographic complication at final available follow-up ranging from 6-24 months. A total of 3 screws (0.49%) were replaced intra-operatively. No clinical effects via radiculopathy or neurologic deficit postoperatively were noted. CONCLUSIONS: This is the first report of the use of AR for placement of spinal pedicle screws using minimally invasive techniques.   This series of 164 cases confirmed efficiency and safety of screw placement with the inherent advantages of AR technologies over legacy enabling technologies.

Longitudinal assessment of segmental motion of the cervical spine following total disc arthroplasty: a comparative analysis of devices.

OBJECTIVE: Total disc arthroplasty (TDA) has been shown to be an effective and safe treatment for cervical degenerative disc disease at short- and midterm follow-up. However, there remains a paucity of literature reporting the differences between individual prosthesis designs with regard to device performance. In this study, the authors evaluated the long-term maintenance of segmental range of motion (ROM) at the operative cervical level across a diverse range of TDA devices. METHODS: In this study, the authors retrospectively evaluated all consecutive patients who underwent 1- or 2-level cervical TDA between 2005 and 2020 at a single institution. Patients with a minimum of 6 months of follow-up and lateral flexion/extension radiographs preoperatively, 2 months postoperatively, and at final follow-up were included. Radiographic measurements included static segmental lordosis, segmental range of motion (ROM) on flexion/extension, global cervical (C2-7) ROM on flexion/extension, and disc space height. The paired t-test was used to evaluate improvement in radiographic parameters. Subanalysis between devices was performed using one-way ANCOVA. Significance was determined at p < 0.05. RESULTS: A total of 85 patients (100 discs) were included, with a mean patient age of 46.01 ± 8.82 years and follow-up of 43.56 ± 39.36 months. Implantations included 22 (22.00%) M6-C, 51 (51.00%) Mobi-C, 14 (14.00%) PCM, and 13 (13.00%) ProDisc-C devices. There were no differences in baseline radiographic parameters between groups. At 2 months postoperatively, PCM provided significantly less segmental lordosis (p = 0.037) and segmental ROM (p = 0.039). At final follow-up, segmental ROM with both the PCM and ProDisc-C devices was significantly less than that with the M6-C and Mobi-C devices (p = 0.015). From preoperatively to 2 months postoperatively, PCM implantation led to a significant loss of lordosis (p < 0.001) and segmental ROM (p = 0.005) relative to the other devices. Moreover, a significantly greater decline in segmental ROM from 2 months postoperatively to final follow-up was seen with ProDisc-C, while segmental ROM increased significantly over time with Mobi-C (p = 0.049). CONCLUSIONS: Analysis by TDA device brand demonstrated that motion preservation differs depending on disc design. Certain devices, including M6-C and Mobi-C, improve ROM on flexion/extension from preoperatively to postoperatively and continue to increase slightly at final follow-up. On the other hand, devices such as PCM and ProDisc-C contributed to greater segmental stiffness, with a gradual decline in ROM seen with ProDisc-C. Further studies are needed to understand how much segmental ROM is ideal after TDA for preservation of physiological cervical kinematics.

Paraganglioma of the Spine: Review of 6 Cases in 20 Years at a Single Institution.

BACKGROUND AND OBJECTIVES: Paragangliomas are rare neuroendocrine tumors that may localize to the spine causing progressive low back pain variably accompanied by radiculopathy. Recurrence, follow-up duration, and role of adjuvant therapy remain unestablished. METHODS: We interrogated our institution's histopathology database for all confirmed cases of spinal paraganglioma between 2000 and 2021. Patient records were retrospectively reviewed to extract diagnostic features, operative treatment, and follow-up outcomes. RESULTS: 6 cases of spinal paraganglioma were surgically treated (67% female vs. 33% male, mean age = 51.3 years). Preoperative symptom duration did not correlate with tumor size (Spearman r = 0.154, P = 0.80). The mean postoperative follow-up duration lasted 3.3 years (range = 2-96 months). There were an equal number of primary and metastatic lesions. 1 tumor exhibited secretory features and was consequently embolized preoperatively. No residual or recurrent disease was evident in the primary cases; however, 2 metastatic cases recurred within 2 years of surgery and 1 patient died. CONCLUSIONS: Given nonspecific clinical and radiologic features, spinal paragangliomas are diagnosed via biopsy or after surgery. Complete surgical resection is often necessary to alleviate symptoms and prevent tumor recurrence. In cases with benign metastases, long-term surveillance is important and adjuvant medical and radiotherapeutic treatment may be beneficial.

Symptomatic Postoperative Epidural Hematoma in the Lumbar Spine.

A symptomatic postoperative epidural hematoma (SPEH) in the lumbar spine is a complication with variable presentation and the potential to rapidly cause an irrecoverable neurological injury. Significant heterogeneity exists among current case series reporting SPEH in the literature. This review attempts to clarify the known incidence, risk factors, and management pearls. Currently, literature does not support the efficacy of subfascial drains in reducing the incidence of SPEHs and possibly suggests that medication for thromboembolism prophylaxis may increase risk. Acute back pain and progressing lower extremity motor weakness are the most common presenting symptoms of SPEH. Magnetic resonance imaging is the mainstay of diagnostic imaging necessary to confirm the diagnosis, but if not acutely available, an immediate return to the operative theater for exploration without advanced imaging is justified. Treatment of a SPEH consists of emergent hematoma evacuation as a delay in repeat surgery has a deleterious effect on neurological recovery. Outcomes are poorly defined, though a significant portion of patients will have lasting neurological impairments even when appropriately recognized and managed.

Awake Endoscopic Transforaminal Lumbar Interbody Fusion: A Technical Note.

BACKGROUND: Advances in modern spinal fusion techniques have allowed for less peri-operative morbidity and more rapid recovery from surgery. The addition of endoscopy to minimally invasive surgery (MIS) fusion techniques represents the latest progression of efforts to minimize the impact of surgical intervention. TECHNIQUE: MIS transforaminal lumbar interbody fusion (TLIF) is performed endoscopically through a sub-centimeter working portal. Patients undergo light conscious sedation and remain awake to facilitate feedback with the surgeon and enhance post-operative recovery. RESULTS: Previously reported results of the first 100 cases performed by the senior author at a single institution are summarized. This cohort has been characterized by brief post-operative length of stay, low complication profile, and marked improvement in patient-reported outcomes scores, with no cases of pseudarthrosis at 1-year follow up. CONCLUSIONS: The latest technical considerations and adaptations of a novel technique for endoscopic MIS spinal fusion without general anesthesia are described. A refined surgical technique and anesthetic protocol are presented in detail with recommendations for the successful implementation and performance of the procedure.

Trends in Leadership at Spine Surgery Fellowships.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To illustrate demographic trends among spine fellowship leaders (FLs). SUMMARY OF BACKGROUND DATA: No previous study in the orthopedic literature has analyzed the demographic characteristics or past surgical training of FL in an orthopedic sub-specialty. We attempt to illustrate demographic trends among spine fellowship leadership including fellowship directors (FDs) and co-fellowship directors (co-FDs). We also highlight the institutions that have trained these leaders at various levels. METHODS: Our search for FDs was constructed from the 2018 to 2019 North American Spine Surgery (NASS) Fellowship Directory. Datapoints gathered included: age, sex, residency/fellowship training location, time since training completion until FD appointment, length in FD role, and personal research H-index. RESULTS: We identified 103 FLs consisting of 67 FDs, 19 co-FDs, and another 16 individuals with a synonymous leadership title. 96.1% (99) of the leadership consisted of males while 3.9% (4) were female. The mean age was 52.9 years old and the mean h-index of the FLs was 23.8. FLs were trained in orthopedic surgery (n = 89), neurosurgery (n = 13), or combined orthopedic surgery and neurosurgery training (n = 1). The top fellowships programs producing future FLs were: Case Western Reserve University, Cleveland (n = 10), Washington University, St. Louis (n = 9), and Rothman Orthopaedic Institute, Thomas Jefferson University, Philadelphia (n = 7). CONCLUSION: Spine surgery fellowship directors are more likely to have graduated from certain residency and fellowship programs. This finding could be a result of the training provided by these centers or the institution's predilection to select applicants that are more likely to later seek academic leadership roles post-training. LEVEL OF EVIDENCE: 4.

The association of mental health disease with perioperative outcomes following femoral neck fractures.

INTRODUCTION: Mental illness in the United States is a growing problem, leading to significant implications for those effected as well as direct and indirect costs to the health care system. The association between psychiatric comorbidity and increased risk of perioperative adverse events has previously been described following elective orthopedic surgery, however, there is a paucity of literature evaluating the correlation between mental health disease and outcomes in patients in an orthopedic trauma setting. METHODS: Utilizing data from the US National Hospital Discharge Survey, all patients undergoing surgery for femoral neck fracture were identified between the years 1990 and 2007. The association of depression, anxiety, dementia and schizophrenia on surgical outcomes were then analyzed using univariate regression analysis. RESULTS: A cohort of 2,432,931 patients was identified. All psychiatric comorbidities were associated with a lower rate of routine discharge home following surgery (p < 0.001). Schizophrenia was associated with increased odds of any adverse event (p < 0.001), acute post-operative mechanical complications (p < 0.001) and increased length of stay (p < 0.001). DISCUSSION: Patients undergoing surgery for femoral neck fracture with comorbid psychiatric illness are at increased risk for non-routine discharge. Schizophrenia is independently associated with an increased risk for post-operative complications. An awareness of these risks should optimize preoperative multidisciplinary patient care planning so as to maximize patient outcome and minimize resource utilization.

Proximal Tibial Reconstruction After Tumor Resection: A Systematic Review of the Literature.

BACKGROUND: The proximal part of the tibia is a common location for primary bone tumors, and many options for reconstruction exist following resection. This anatomic location has a notoriously high complication rate, and each available reconstruction method is associated with unique risks and benefits. The most commonly utilized implants are metallic endoprostheses, osteoarticular allografts, and allograft-prosthesis composites. There is a current lack of data comparing the outcomes of these reconstructive techniques in the literature. METHODS: A systematic review of peer-reviewed observational studies evaluating outcomes after proximal tibial reconstruction was conducted, including both aggregate and pooled data sets and utilizing a Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) review for quality assessment. Henderson complications, amputation rates, implant survival, and functional outcomes were evaluated. RESULTS: A total of 1,643 patients were identified from 29 studies, including 1,402 patients who underwent reconstruction with metallic endoprostheses, 183 patients who underwent reconstruction with osteoarticular allografts, and 58 patients who underwent with reconstruction with allograft-prosthesis composites. The mean follow-up times were 83.5 months (range, 37.3 to 176 months) for the metallic endoprosthesis group, 109.4 months (range, 49 to 234 months) for the osteoarticular allograft group, and 88.8 months (range, 49 to 128 months) for the allograft-prosthesis composite reconstruction group. The mean patient age per study ranged from 13.5 to 50 years. Patients with metallic endoprostheses had the lowest rates of Henderson Type-1 complications (5.1%; p < 0.001), Type-3 complications (10.3%; p < 0.001), and Type-5 complications (5.8%; p < 0.001), whereas, on aggregate data analysis, patients with an osteoarticular allograft had the lowest rates of Type-2 complications (2.1%; p < 0.001) and patients with an allograft-prosthesis composite had the lowest rates of Type-4 complications (10.2%; p < 0.001). The Musculoskeletal Tumor Society (MSTS) scores were highest in patients with an osteoarticular allograft (26.8 points; p < 0.001). Pooled data analysis showed that patients with a metallic endoprosthesis had the lowest rates of sustaining any Henderson complication (23.1%; p = 0.009) and the highest implant survival rates (92.3%), and patients with an osteoarticular allograft had the lowest implant survival rates at 10 years (60.5%; p = 0.014). CONCLUSIONS: Osteoarticular allograft appears to lead to higher rates of Henderson complications and amputation rates when compared with metallic endoprostheses. However, functional outcomes may be higher in patients with osteoarticular allograft. Further work is needed using higher-powered randomized controlled trials to definitively determine the superiority of one reconstructive option over another. In the absence of such high-powered evidence, we encourage individual surgeons to choose reconstructive options based on personal experience and expertise. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Dysphagia following lumbar spine surgery in the setting of undiagnosed DISH of the cervical spine: a case report.

Dysphagia is an often multifactorial pathology affecting many elderly patients. In addition to global neuromuscular change with normal aging, one component of its etiology may be direct compression of the pharynx or esophagus from overgrown bone from the anterior cervical spine. Diffuse idiopathic skeletal hyperostosis (DISH) is one condition that may contribute to this phenomenon. Of relatively high incidence (2.5% to 33.3%) in elderly populations, DISH has been described in the cervical spine though more frequently affects other spinal regions. The clinical case of an elderly man who developed significant dysphagia after undergoing lumbar spine surgery for spinal stenosis caused by DISH is presented. Awareness of the involvement in his cervical spine before surgery would likely have enabled a more prompt diagnosis of the etiology of dysphagia and allowed for peri-operative optimization of swallowing function to reduce morbidity. We recommend routine preoperative imaging of the cervical spine in all patients with a diagnosis of DISH to stratify risk for development of postoperative dysphagia.

Is There a Correlation Between Preoperative or Postoperative Vitamin D Levels with Pseudarthrosis, Hardware Failure, and Revisions After Lumbar Spine Fusion?

BACKGROUND: Vitamin D deficiency is a well-known cause of postoperative complications in patients undergoing orthopedic surgery. Orthopedic complications seen in vitamin D deficiency include nonunion, pseudarthrosis, and hardware failure. We seek to investigate the relationship between vitamin D deficiency and outcomes after lumbar spinal fusions. METHODS: A retrospective patient chart review was conducted at a single center for all patients who underwent lumbar spinal fusions from January 2015 to September 2017 with preoperative or postoperative vitamin D laboratory values. We recorded demographics, social history, medications, pre-existing medical conditions, bone density (dual-energy x-ray absorptiometry) T-scores, procedural details, 1-year postoperative Visual Analog Score (VAS), documented pseudarthrosis, revisions, and hardware failure. A total of 150 patients were initially included in the cohort for analysis. RESULTS: Overall, preoperative and postoperative vitamin D levels were not significantly associated with a vast majority of the patient characteristics studied, including comorbidities, medications, or surgical diagnoses (P > 0.05). Age at surgery was significantly associated with vitamin D levels; older patients had higher serum levels of vitamin D both preoperatively (P = 0.03) and postoperatively (P = 0.01). Those with a higher average body mass index had lower vitamin D in both groups (P = 0.02). Vitamin D levels were not significantly associated with rates of postoperative pseudarthrosis, revision, or hardware complications (P > 0.05). VAS pain score at 1 year and smoking status preoperatively or postoperatively were not associated with vitamin D levels (P > 0.05). CONCLUSIONS: Both preoperative and postoperative vitamin D levels were not significantly associated with an increased or decreased risk of pseudarthrosis, revision surgery, hardware failure, or 1-year VAS pain score after lumbar spine fusion surgery.

Endoscopic Lumbar Surgery: The State of the Art in 2019

This study was aimed to provide a brief historical perspective to facilitate appreciation of current techniques, describe outcomes of endoscopic lumbar surgery relative to those of existing techniques, and identify topics in need of study and future directions for the field of endoscopic lumbar surgery. Using the PubMed database, a comprehensive search was conducted to identify peer-reviewed English language articles pertaining to endoscopic lumbar surgery. Lack of focus on pertinent techniques or lack of outcome measures constituted exclusion criteria. A majority of included articles were published from 2015­2019. A context with which to appreciate the application of endoscopic lumbar techniques is established. An abundance of case series and several recent comparison studies have documented the benefits and potential pitfalls of these methods in the past two decades. The advantages of endoscopic lumbar spine surgery are widely touted to include reduced perioperative morbidity, including blood loss, operative time and immediate postoperative recovery, minimal structural trauma resulting from surgery, generally positive patient report outcome scores and the potential to contain costs. Additional high-quality research assessing outcomes of endoscopic lumbar surgery are certainly needed and currently expected given the rapid expansion of the field in recent years.

Inpatient Outcomes After Elective Lumbar Spinal Fusion for Patients with Human Immunodeficiency Virus in the Absence of Acquired Immunodeficiency Syndrome.

BACKGROUND: To our knowledge, no prior study has evaluated outcomes after elective lumbar spinal surgery in human immunodeficiency virus (HIV) patients without acquired immunodeficiency syndrome (AIDS). This review investigated the impact of HIV-positive status (without AIDS) on outcomes after elective lumbar fusion for degenerative disc disease (DDD). METHODS: Adult patients registered in the Nationwide Inpatient Sample (2002-2011) undergoing elective lumbar fusion for DDD were extracted. Multivariable regression techniques were used to explore the association of HIV positivity with outcomes after lumbar fusion. RESULTS: This cohort included 612,000 hospitalizations (0.07% were HIV positive) of lumbar fusion for DDD. Compared with HIV-negative patients undergoing lumbar fusion, HIV-positive patients were younger (47 vs. 55 years), male (61% vs. 42%), largely insured by Medicare (30% vs. 5%), and had higher rates of chronic obstructive pulmonary disease (23.7% vs. 14.6%) (all P < 0.001) but had lower rates of obesity, hypertension, and diabetes (all P < 0.001). Multivariable models demonstrated HIV positivity to be associated with higher odds for an adverse event (odds ratio [OR], 1.92; P < 0.001), in-hospital mortality (OR, 39.91; P < 0.001), wound complications (OR, 2.60; P = 0.004), respiratory (OR, 5.43; P < 0.001) and neurologic (OR, 1.96; P = 0.039) complications, and higher costs (7.1% higher; P = 0.011) compared with non-HIV patients. There were no differences in thromboembolic events, cardiac or gastrointestinal complications, discharge disposition, or length of stay. CONCLUSIONS: Even in this selected cohort of well-controlled HIV patients, there were high complications, with concerning rates of death and respiratory complications. These data shed new light on elective spine surgery in HIV patients and may influence the treatment algorithm of surgeons who are familiar with older papers.

The most influential publications in cervical myelopathy.

Management of cervical myelopathy (CM) has continued to evolve through a better understanding of the long-term outcomes of this diagnosis as well as improved diagnostic guidelines. More recent literature continues to expand the field, but certain publications can be distinguished from others due to their lasting impact. Using the Clarivate Analytics Web of Science, search phrases were used to identify publications pertaining to CM. The fifty most cited articles were isolated. The frequency of citations, year of publication, country of origin, journal of publication, level of evidence (LOE), article type, as well as contributing authors and institutions were recorded. We also highlighted the five most cited articles (per year) from the past 10 years. Publications included ranged from 1952-2011, with the plurality of articles published during 2000-2009 (n=21; 42%). The most cited paper was Hillibrand's 1999 reporting of adjacent segment disease rates following cervical fusions, followed by Hirabayashi's 1983 review of his cervical laminoplasty outcomes. The third most cited was Brain's 1952 review of the manifestations of cervical spondylosis. Spine contributed the most publications (n=26; 52%). A LOE of III was the most common (n=30; 60%). Clinical outcome articles were the most frequent type (n=28; 56%). Osaka University (Japan) and Kazou Yonenobu had the most contributions. Ames or Fehlings were the first or last author in each of the five most influential articles from the past 10 years. This bibliometric citation analysis identifies the most influential articles regarding CM. There are few publications with a high LOE, and more high powered studies are needed. Knowledge of these "classic" publications allows for a better overall understanding of the diagnosis, treatment, and future direction of research of CM.