Artificial intelligence assistance for the measurement of full alignment parameters in whole-spine lateral radiographs

BACKGROUND

Measuring spinal alignment with radiological parameters is essential in patients with spinal conditions likely to be treated surgically. These evaluations are not usually included in the radiological report. As a result, spinal surgeons commonly perform the measurement, which is time-consuming and subject to errors. We aim to develop a fully automated artificial intelligence tool to assist in measuring alignment parameters in whole-spine lateral radiograph (WSL X-rays).

MATERIAL AND METHODS

We developed a tool called Vertebrai that automatically calculates the global spinal parameters (GSP): Pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), L1-L4 angle, L4-S1 lumbo-pelvic angle, T1 pelvic angle (TPA), sagittal vertical axis (SVA), cervical lordosis (CL), C1-C2 lordosis, lumbar lordosis (LL), mid-thoracic kyphosis (MTK), proximal thoracic kyphosis (PTK), global thoracic kyphosis (GTK), T1 slope (T1S), C2-C7 plummet (cSVA), spino-sacral angle (SSA), C7 tilt (C7T), global tilt (GT), spinopelvic tilt (T1SPi) and hip odontoid axis (OD-HA). We assessed human-AI interaction instead of AI performance alone. We compared the time to measure GSP and inter-rater agreement with and without AI assistance. Two institutional datasets were created with 2267 multilabel images for classification, and 784 WSL X-rays with reference standard landmark labeled by spinal surgeons.

RESULTS

Vertebrai significantly reduced the measurement time comparing spine surgeons with AI assistance and the AI algorithm alone, without human intervention (3 minutes vs 0.26 minutes; p < 0.05). Vertebrai achieved an average accuracy of 83% in detecting abnormal alignment values, with the SS parameter exhibiting the lowest accuracy at 61.5% and T1SPi demonstrating the highest accuracy at 100%. Intra-class correlation analysis revealed a high level of correlation and consistency in the global alignment parameters.

CONCLUSIONS

Vertebrai's measurements can accurately detect alignment parameters, making it a promising tool for measuring GSP automatically.

Utility of the Modified 5-Items Frailty Index to Predict Complications and Mortality After Elective Cervical, Thoracic and Lumbar Posterior Spine Fusion Surgery: Multicentric Analysis From ACS-NSQIP Database

STUDY DESIGN

Retrospective review of multicentric data.

OBJECTIVES

The modified 5-item frailty index is a relatively new tool to assess the post-operative complication risks. It has been recently shown a good predictive value after posterior lumbar fusion. We aimed to compare the predictive value of the modified 5-item frailty index in cervical, thoracic and lumbar surgery.

METHODS

The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) Database 2015-2020 was used to identify patients who underwent elective posterior cervical, thoracic, or lumbar fusion surgeries for degenerative conditions. The mFI-5 score was calculated based on the presence of 5 co-morbidities: congestive heart failure within 30 days prior to surgery, insulin-dependent or noninsulin-dependent diabetes mellitus, chronic obstructive pulmonary disease or pneumonia, partially dependent or totally dependent functional health status at time of surgery, and hypertension requiring medication. Multivariate analysis was used to assess the independent impact of increasing mFI-5 score on the postoperative morbidity while controlling for baseline clinical characteristics.

RESULTS

53 252 patients were included with the mean age of 64.2 ± 7.2. 7946 suffered medical complications (14.9%), 1565 had surgical complications (2.9%), and 3385 were readmitted (6.3%), 363 died (.68%) within 30 days postoperative (6.3%). The mFI-5 items score was significantly associated with higher rates of complications, readmission, and mortality in cervical, thoracic, and lumbar posterior fusion surgery.

CONCLUSION

The modified 5-item frailty score is a reliable tool to predict complications, readmission, and mortality in patients planned for elective posterior spinal fusion surgery.

Navigating the Indeterminate Zone: Surgeons' Decision-Making Factors in Treating Vertebral Metastases with Spinal Instability Scores of 7-12

BACKGROUND

The Spinal Instability Neoplastic Score (SINS) classification system is a validated and the most widely accepted instrument for defining instability in vertebral metastasis (VM), in which lesions scoring between 7 and 12 are defined as indeterminate and the treatment is controversial. This study aimed to determine which variables more frequently are considered by spine surgeons for choosing between the conservative and the surgical treatment of VMs among patients with an indeterminate SINS.

METHODS

A single-round online survey was conducted with 10 spine surgeons with expertise in the management of VMs from our AO Spine Region. In this survey, each surgeon independently reviewed demographic and cancer-related variables of 36 real-life cases of patients with vertebral metastases scored between 7 and 12 in the SINS. Bivariate and multivariate analyses were performed to identify significant SINS and non-SINS variables influencing the decision-making on surgical treatment.

RESULTS

The most commonly variables considered important were the SINS element "mechanical pain", rated important for 44.4% of the cases, "lesion type" for 36.1%, and "degree of vertebral collapse" and the non-SINS factor "tumor histology" rated for 13.9% of cases. By far the factor most commonly rated unimportant was "posterior element compromise" (in 72.2% of cases).

CONCLUSIONS

Surgeons relied on mechanical pain and type of metastatic lesion for treatment choices. Vertebral collapse, spinal malalignment, and mobility were less influential. Spinal mobility was a predictor of surgical versus non-surgical treatment. The only variables not identified either by surgeons themselves or as a predictor of surgery selection was the presence/degree of posterolateral/posterior element involvement.

Assessing the Accessibility, Engagement, and Value of the Virtual Global Spine Conference as an Educational Platform for Spine: A Three-Year Review

INTRODUCTION

The Coronavirus disease 2019 pandemic ushered a paradigm shift in medical education, accelerating the transition to virtual learning in select cases. The Virtual Global Spine Conference (VGSC), launched at the height of the pandemic, is a testament to this evolution, providing an independent educational series for spine care professionals worldwide. This study assesses VGSC's 3-year performance, focusing on accessibility, engagement, and educational value.

METHODOLOGY

Through retrospective data analysis from April 2020 to August 2023, we examined our social media metrics to measure VGSC's reach and impact.

RESULTS

Over the study period, VGSC's webinars successfully attracted 2337 unique participants, maintaining an average attendance of 47 individuals per session. The YouTube channel demonstrated significant growth, amassing over 2693 subscribers and releasing 168 videos. These videos collectively garnered 112,208 views and 15,823.3 hours of watch time. Viewer demographics reveal a predominant age group of 35-44 years, representing 56.81% of the audience, closely followed by the 25-34 age group at 40.2%. Male participants constituted 78.95% of the subscriber base. Geographically, the viewership primarily originates from the United States, with India, Canada, South Korea, and the United Kingdom also contributing substantial audience numbers. The VGSC's presence on the "X account" has grown to 2882 followers, significantly enlarging the digital community and fostering increased engagement.

CONCLUSIONS

The VGSC has demonstrated significant value as a virtual educational tool in spine education. Its diverse content and ease of access will likely enable it to drive value well into the post-pandemic years. Maintaining and expanding engagement, beyond North America in particular, remains a priority.

Treatment of unilateral cervical facet fractures without evidence of dislocation or subluxation: a narrative review and proposed treatment algorithm

Isolated cervical spine facet fractures are often overlooked. The primary imaging modality for diagnosing these injuries is a computed tomography scan. Treatment of unilateral cervical facet fractures without evidence of dislocation or subluxation remains controversial. The available evidence regarding treatment options for these fractures is of low quality. Risk factors associated with the failure of nonoperative treatment are: comminution of the articular mass or facet joint, acute radiculopathy, high body mass index, listhesis exceeding 2 mm, fragmental diastasis, acute disc injury, and bilateral fractures or fractures that adversely affect 40% of the intact lateral mass height or have an absolute height of 1 cm.

Single-Position Prone Lateral Lumbar Interbody Fusion Technique Guide: Surgical Tips and Tricks

Lateral lumbar interbody fusion (LLIF) is a popular technique as it allows for the placement of a large interbody implant through a retroperitoneal, transpsoas working corridor. Historically, the interbody is placed with the patient in lateral decubitus and then repositioned to prone for the posterior instrumentation. While this has been an effective and successful technique, removing the interoperative flip would improve the efficiency of these cases. This has led to modified LLIF approaches including single-position prone LLIF (pLLIF). This modification has shown to be an efficient and powerful technique; however, learning to navigate the LLIF approach in the prone position has its own challenges. The purpose of this article is to provide a detailed description of our pLLIF technique while simultaneously introducing surgical tips to overcome the challenges of the approach and optimize the implantation of the interbody device.

Technical Nuances of Anterior Column Construction for the Treatment of Osteomyelitis-Induced Cervical Kyphoscoliotic Deformity: An Operative Video Illustration

Pyogenic vertebral osteomyelitis is a bacterial infection of the vertebral body often caused by hematogenous spread from a distant site with 3%-11% of cases affecting the cervical spine.1,2 Patients at risk for osteomyelitis are intravenous drug users, patients with diabetes, patients in dialysis, and males older than 50 years of age. In severe cases where infection causes osseous destruction of the vertebral column lending to a loss of normal sagittal and coronal plane alignment, neurologic impairment, or spinal instability, surgical correction may be required.3 A 38-year-old woman with a medical history of intravenous drug use presented with a 1-week history of progressive paresthesias, subjective loss of lower extremity sensation, and severe right upper extremity weakness. Neurologic examination was notable for significant weakness in the right deltoids, biceps, and triceps. Magnetic resonance imaging cervical spine revealed significant kyphosis at C4-C5 secondary to destruction of the C4 and C5 vertebral bodies and anterior and posterior epidural fluid collection at C2-C3 and C7-T1, respectively. Surgery was proposed through a combined anteroposterior approach with head and neck surgeons. Anteriorly, she underwent a C2-C3 and C6-C7 ACDF and C4, C5 corpectomies (Video 1). The patient was then transitioned to the prone position and underwent C3-T3 posterior fusion with instrumentation and C3-C7 laminectomies. Correction of sagittal imbalance should restore normal physiologic spinal alignment while promoting a successful fusion.4 The patient was discharged to acute rehabilitation after an uneventful postoperative course. At 5-month follow-up, she has regained antigravity strength in right upper extremity and reports significant reduction in neck pain.

Minimally Invasive Approaches for Lumbosacral Plexus Schwannomas

BACKGROUND AND OBJECTIVES

Lumbosacral plexus schwannomas (LSPSs) are benign, slow-growing tumors that arise from the myelin sheath of the lumbar or sacral plexus nerves. Surgery is the treatment of choice for symptomatic LSPSs. Conventional retroperitoneal or transabdominal approaches provide wide exposure of the lesion but are often associated with complications in the abdominal wall, lumbar or sacral plexus, ureter, and intraperitoneal organs. Advances in technology and minimally invasive (MIS) techniques have provided alternative approaches with reliable efficacy compared with traditional open surgery. We describe 3 MIS approaches using tubular retractor systems according to the lesion level.

METHODS

This was a multicenter, retrospective observational cohort study to evaluate the use of MIS tubular approaches for surgical resection of LSPSs. We included 23 lumbar and upper sacral plexus schwannomas. Clinical presentation, spinal level, surgical duration, degree of resection, days of hospitalization, pathological anatomy of the tumor, approach-related surgical difficulties, and outcomes were collected.

RESULTS

The posterior oblique approach was used in 43.5% of the cases, the transpsoas approach in 39.1%, and the transiliac in 17.4%. The mean operative time was 3.3 hours, and the mean hospitalization was 2.5 days. All tumors were WHO grade 1 schwannoma. Postoperative MRI confirms gross total resection in 91.3% of the patients. No patient requires instrumentation. The pros and cons of each approach were summarized.

CONCLUSION

The MIS approaches adapted to the lumbar level may improve surgeons' comfort allowing a safe resection of retroperitoneal LSPS.

Lumbar Tubular Decompression: Barriers and Limitations Hampering the Technique's Dissemination Across Latin America

OBJECTIVES

We sought to explore the barriers and limitations preventing the widespread use of tubular lumbar spine decompressions in Latin America.

METHODS

A cross-sectional study was performed using a survey designed specifically by the authors. This survey was mailed to all spine surgeons who are members of AO Spine Latin America. Eighty-seven surgeons spanning 15 Latin American countries answered the survey.

RESULTS

Thirty-one percent of participating surgeons claimed they needed to adapt their technique to perform minimally invasive tubular surgeries. Meanwhile, though 70.5% answered they do not consider tubular surgery expensive, 32.8% lacked access to standard equipment like a complete set of retractors or curved high-speed drill.

CONCLUSIONS

Several barriers limit the development of tubular spine surgery in Latin America. The most important discrepancies between surgeons' preferred equipment and their availability for such operations are high-speed drills, bayoneted instruments, and hemostatic agents.

Comparison of complication rates between anterior versus posterior approaches for treating unstable Hangman's fracture. A systematic review and meta-analysis

Study design

Systematic Review and Meta-analysis.

Objective

To compare the complication rates associated with anterior and posterior approaches for the surgical treatment of unstable hangman's fractures.

Methods

A systematic review and meta-analysis were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in PubMed, Web of Science, and Scopus databases to identify comparative studies reporting complications of anterior versus posterior approaches for the treatment of unstable hangman's fractures.

Results

The search yielded 1163 papers from which 5 studies were fully included. One hundred fifteen (115) patients were operated on using an anterior approach versus 65 through a posterior approach. The average complication rates for the anterior and posterior approaches were 26.1 % and 13.8 %, respectively. No complications following the anterior approach required pharmacological or surgical intervention (Clavien-Dindo, Grade 1), while 88.9 % of complications following the posterior approach did (Clavien-Dindo, Grade 2).

Conclusion

No significant differences in the complication rates were found when comparing anterior versus posterior surgery for treating a C2 traumatic spondylolisthesis. However, most of the complications presented in the posterior surgery group were more severe.

Minimally Invasive Surgery for Traumatic Thoracolumbar Fractures: A Cross-Sectional Study of Spine Surgeons

OBJECTIVE

To describe the perceived feasibility of minimally invasive surgical treatment of thoracolumbar fractures among spine surgeons in Latin American centers.

METHODS

This is a cross-sectional study on minimally invasive surgical treatment for unstable thoracolumbar fractures. We conducted an online survey of spine surgeons working in Latin American centers, administered between December 16, 2022 and January 15, 2023. A nonprobabilistic sample was selected (snowball sampling). A questionnaire was sent by email and other messaging applications.

RESULTS

Data were extracted from 134 surgeons. The majority of the respondents were from Brazil (n = 30, 22.4%), Mexico (n = 24, 17.9%), Argentina (n = 22, 16.4%), and Chile (n = 15, 11.2%). Their mean age was 46.53 years (standard deviation, 9.7; range 31-67) and almost all were males (n = 128, 95.5%). Most respondents were orthopedists (n = 85, 63.4%) or neurosurgeons (n = 49, 36.9%). Most of the respondents (n = 110, 82.1%) reported at least some difficulty using minimally invasive techniques for thoracolumbar fractures. It should be noted that there were significant regional differences between the surgeons' responses (P = 0.017). Chilean surgeons reported better results than others.

CONCLUSION

Spinal surgeons from Latin American centers have identified challenges and obstacles to performing minimally invasive surgery for thoracolumbar trauma. The survey found that a majority of respondents experienced some level of difficulty, with regional variations. The most frequently reported difficulties were the high cost of the procedure, patient insurance restrictions, and long insurance approval times.

Prevention of Surgical Site Infections in Spine Surgery: An International Survey of Clinical Practices Among Expert Spine Surgeons

STUDY DESIGN

Questionnaire-based survey.

OBJECTIVES

Surgical site infection (SSI) is a common complication in spine surgery but universal guidelines for SSI prevention are lacking. The objectives of this study are to depict a global status quo on implemented prevention strategies in spine surgery, common themes of practice and determine key areas for future research.

METHODS

An 80-item survey was distributed among spine surgeons worldwide via email. The questionnaire was designed and approved by an International Consensus Group on spine SSI. Consensus was defined as more than 60% of participants agreeing to a specific prevention strategy.

RESULTS

Four hundred seventy-two surgeons participated in the survey. Screening for Staphylococcus aureus (SA) is not common, whereas preoperative decolonization is performed in almost half of all hospitals. Body mass index (BMI) was not important for surgery planning. In contrast, elevated HbA1c level and hypoalbuminemia were often considered as reasons to postpone surgery. Cefazoline is the common drug for antimicrobial prophylaxis. Alcohol-based chlorhexidine is mainly used for skin disinfection. Double-gloving, wound irrigation, and tissue-conserving surgical techniques are routine in the operating room (OR). Local antibiotic administration is not common. Wound closure techniques and postoperative wound dressing routines vary greatly between the participating institutions.

CONCLUSIONS

With this study we provide an international overview on the heterogeneity of SSI prevention strategies in spine surgery. We demonstrated a large heterogeneity for pre-, peri- and postoperative measures to prevent SSI. Our data illustrated the need for developing universal guidelines and for testing areas of controversy in prospective clinical trials.

Pedicle subtraction metallectomy with complex posterior reconstruction for fixed cervicothoracic kyphosis: illustrative case

BACKGROUND

Iatrogenic cervical deformity is a devastating complication that can result from a well-intended operation but a poor understanding of the individual biomechanics of a patient's spine. Patient factors, such as bone fragility, high T1 slope, and undiagnosed myopathies often play a role in perpetuating a deformity despite an otherwise successful surgery. This imbalance can lead to significant morbidity and a decreased quality of life.

OBSERVATIONS

A 55-year-old male presented to the authors' clinic with a chin-to-chest deformity and cervical myelopathy. He previously had an anterior C2-T2 fixation and a posterior C1-T6 instrumented fusion. He subsequently developed screw pullout at multiple levels, so the original surgeon removed all of the posterior hardware. The T1 cage (original corpectomy) severely subsided into the body of T2, generating an angular kyphosis that eventually developed a rigid osseous circumferential union at the cervicothoracic junction with severe cord compression. An anterior approach was not feasible; therefore, a 3-column osteotomy/fusion in the upper thoracic spine was planned whereby 1 of the T2 screws would need to be removed from a posterior approach for the reduction to take place.

LESSONS

This case highlights the devastating effect of a hardware complication leading to a fixed cervical spine deformity and the complex decision making involved to safely correct the challenging deformity and restore function.

CT Scan in Subaxial Cervical Facet Injury: Is It Enough for Decision-Making?

STUDY DESIGN

Cross-sectional survey.

OBJECTIVES

Assessment of subaxial cervical facet injuries using the AO Spine Subaxial Cervical Spine Injury Classification System is based on CT scan findings. However, additional radiological evaluations are not directly considered. The aim of this study is to determine situations in which spine surgeons request additional radiological exams after a facet fracture.

METHODS

A survey was sent to AO Spine members from Latin America. The evaluation considered demographic variables, routine use of the Classification, as well as the timepoint at which surgeons requested a cervical MRI, a vascular study, and/ or dynamic radiographs before treatment of facet fractures.

RESULTS

There was 229 participants, mean age 42.9 ± 10.2 years; 93.4% were men. Orthopedic surgeons 57.6% with 10.7 ± 8.7 years of experience in spine surgery. A total of 86% used the Classification in daily practice. An additional study (MRI/vascular study/and dynamic radiographs) was requested in 53.3%/9.6%/43.7% in F1 facet injuries; 76.0%/20.1%/50.2% in F2; 89.1%/65.1%/28.4% in F3; and 94.8%/66.4%/16.6% in F4. An additional study was frequently required: F1 72.5%, F2 86.9%, F3 94.7%, and F4 96.1%.

CONCLUSIONS

Spine surgeons generally requested additional radiological evaluations in facet injuries, and MRI was the most common. Dynamic radiographs had a higher prevalence for F1/F2 fractures; vascular studies were more common for F3/F4 especially among surgeons with fewer years of experience. Private hospitals had a lower spine trauma cases/year and requested more MRI and more dynamic radiographs in F1/F2. Neurosurgeons had more vascular studies and dynamic radiographs than orthopedic surgeons in all facet fractures.

Single-Position Transpsoas Corpectomy and Posterior Instrumentation in the Thoracolumbar Spine for Different Clinical Scenarios

BACKGROUND

The concept of single-position spine surgery has been gaining momentum because it has proven to reduce operative time, blood loss, and hospital length of stay with similar or better outcomes than traditional dual-position surgery. The latest development in single-position spine surgery techniques combines either open or posterior pedicle screw fixation with transpsoas corpectomy while in the lateral or prone positioning.

OBJECTIVE

To provide, through a multicenter study, the results of our first patients treated by single-position corpectomy.

METHODS

This is a multicenter retrospective study of patients who underwent corpectomy and instrumentation in the lateral or prone position without repositioning between the anterior and posterior techniques. Data regarding demographics, diagnosis, neurological status, surgical details, complications, and radiographic parameters were collected. The minimum follow-up for inclusion was 6 months.

RESULTS

Thirty-four patients were finally included in our study (24 male patients and 10 female patients), with a mean age of 51.2 (SD ± 17.5) years. Three-quarter of cases (n = 27) presented with thoracolumbar fracture as main diagnosis, followed by spinal metastases and primary spinal infection. Lateral positioning was used in 27 cases, and prone positioning was used in 7 cases. The overall rate of complications was 14.7%.

CONCLUSION

This is the first multicenter series of patients who underwent single-position corpectomy and fusion. This technique has shown to be safe and effective to treat a variety of spinal conditions with a relatively low rate of complications. More series are required to validate this technique as a possible standard approach when thoracolumbar corpectomies are indicated.

Time to surgery for adolescent idiopathic scoliosis: How long does it take? A multicenter study

Study design

Retrospective review of multicentric data.

Objectives

To estimate the time from initial visit to surgery in adolescent idiopathic scoliosis (AIS) patients and the main reasons for the time to surgery in a multicenter study.

Methods

This retrospective study evaluated 509 patients with AIS from 16 hospitals across six Latin American countries. From each hospital's deformity registry, the following patient data were extracted: demographics, main curve Cobb angle, Lenke Classification at the initial visit and time of surgery, time from indication-for-surgery to surgery, curve progression, Risser skeletal-maturity score and causes for surgical cancelation or delay. Surgeons were asked if they needed to change the original surgical plan due to curve progression. Data also were collected on each hospital's waiting list numbers and mean delay to AIS surgery.

Results

66.8% of the patients waited over six months and 33.9% over a year. Waiting time was not impacted by the patient's age when surgery first became indicated (p = 0.22) but waiting time did differ between countries (p < 0.001) and hospitals (p < 0.001). Longer time to surgery was significantly associated with increasing magnitude of the Cobb angle through the second year of waiting (p < 0.001). Reported causes for delay were hospital-related (48.4%), economic (47.3%), and logistic (4.2%). Oddly, waiting time for surgery did not correlate with the hospital's reported waiting-list lengths (p = 0.57).

Conclusion

Prolonged waits for AIS surgery are common in Latin America, with rare exceptions. At most centers, patients wait over six months, most commonly for economic and hospital-related reasons. Whether this directly impacts surgical outcomes in Latin America still must be studied.

Risk Factors for Postoperative Complications After Surgical Treatment of Type B and C Injuries of the Thoracolumbar Spine

BACKGROUND

Unstable thoracolumbar spinal injuries benefit from surgical fixation. However, perioperative complications significantly affect outcomes in surgicallytreated spine patients. We evaluated associations between risk factors and postoperative complications in patients surgically treated for thoracolumbar spine fractures.

METHODS

We conducted a retrospective multicenter study collating data from 21 spine centers across 9 countries on the treatment of AOSpine types B and C injuries of the thoracolumbar spine treated via a posterior approach. Comparative analysis was performed between patients with postoperative complications and those without. Univariate and multivariable analyses were performed.

RESULTS

Among 535 patients, at least 1 complication occurred in 43%. The most common surgical complication was surgical-site infection (6.9%), while the most common medical complication was urinary tract infection (13.8%). Among 136 patients with American Spinal Injury Association (ASIA) Impairment Scalelevel A disability, 77.9% experienced at least 1 complication. The rate of complications also rose sharply among patients waiting >3 days for surgery (P<0.001), peaking at 68.4% among patients waiting ≥30 days. On multivariable analysis, significant predictors of complications were surgery at a governmental hospital (odds ratio = 3.38, 95% confidence interval = 1.73-6.60), having ≥1 comorbid illness (2.44, 1.61-3.70), surgery delayed due to health instability (2.56, 1.50-4.37), and ASIA Impairment Scalelevel A (3.36, 1.78-6.35), while absence of impairment (0.39, 0.22-0.71), ASIAlevel E (0.39, 0.22-0.67) and, unexpectedly, delay caused by operating room unavailability (0.60, 0.36-0.99) were protective.

CONCLUSIONS

Types B and C thoracolumbar spine injuries are associated with a high risk of postoperative complications, especially common at governmental hospitals, and among patients with comorbidity, health instability, longer delays to surgery, and worse preoperative neurologic status.

Percutaneous Versus Open Pedicle Screw Fixation for Pyogenic Spondylodiscitis of the Thoracic and Lumbar Spine: Systematic Review and Meta-Analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

This meta-analysis aimed to compare percutaneous (PPS) versus open pedicle screw (OPS) fixation for treatment of thoracic and lumbar spondylodiscitis.

SUMMARY OF BACKGROUND DATA

Pyogenic spondylodiscitis of the thoracic and lumbar spine can produce instability, deformity, and/or neurological compromise. When medical treatment is unsuccessful, surgical treatment is indicated, with the conventional open approach the usual standard of care. However, percutaneous techniques can be advantageous in medically vulnerable patients.

MATERIALS AND METHODS

A literature search was performed using the PubMed, Web of Science, and Scopus databases, looking for comparative articles on pyogenic spondylodiscitis requiring surgical stabilization with pedicle screws. This systematic review is reported according to PRISMA guidelines.

RESULTS

From 215 articles initially identified, 7 retrospective studies were analyzed, encapsulating an overall sample of 722 patients: 405 male (56.1%) and 317 female (43.9%). The treatment modality was PPS fixation in 342 patients (47.4%) and OPS fixation in 380 (52.6%). For PPS, operating time was 29.75 minutes ( P <0.0001), blood loss 390.18 mL ( P <0.00001), postoperative pain 1.54 points ( P <0.00001), and length of stay 4.49 days ( P =0.001) less than with OPS fixation, and wound infection 7.2% ( P =0.003) less frequent. No difference in screw misplacement ( P =0.94) or loosening ( P =0.33) rates was observed.

CONCLUSION

Employing PPS fixation to treat pyogenic spondylodiscitis of the thoracic and lumbar spine is associated with significantly reduced operating time, blood loss, postoperative pain, length of stay, and rates of wound infection than OPS fixation, with no difference between the 2 treatments in rates of screw misplacement or screw loosening.

Unplanned Readmission Following Early Postoperative Complications After Fusion Surgery in Adult Spine Deformity: A Multicentric Study

STUDY DESIGN

Multicentric retrospective study, Level of evidence III.

OBJECTIVE

The objective of this multicentric study was to analyze the prevalence and risk factors of early postoperative complications in adult spinal deformity patients treated with fusion. Additionally, we studied the impact of complications on unplanned readmission and hospital length of stay.

METHODS

Eight spine centers from 6 countries in Latin America were involved in this study. Patients with adult spinal deformity treated with fusion surgery from 2017 to 2019 were included. Baseline and surgical characteristics such as age, sex, comorbidities, smoking, number of levels fused, number of surgical approaches were analyzed. Postoperative complications at 30 days were recorded according to Clavien-Dindo and Glassman classifications.

RESULTS

172 patients (120 females/52 males, mean age 59.4 ± 17.6) were included in our study. 78 patients suffered complications (45%) at 30 days, 43% of these complications were considered major. Unplanned readmission was observed in 35 patients (20,3%). Risk factors for complications were: Smoking, previous comorbidities, number of levels fused, two or more surgical approaches and excessive bleeding. Hospital length of stay in patients without and with complications was of 7.8 ± 13.7 and 17 ± 31.1 days, respectively (P 0.0001).

CONCLUSION

The prevalence of early postoperative complications in adult spinal deformity patients treated with fusion was of 45% in our study with 20% of unplanned readmissions at 30 days. Presence of complications significantly increased hospital length of stay.

An independent inter- and intra-observer agreement assessment of the AOSpine upper cervical injury classification system

BACKGROUND CONTEXT

The complex anatomy of the upper cervical spine resulted in numerous separate classification systems of upper cervical spine trauma. The AOSpine upper cervical classification system (UCCS) was recently described; however, an independent agreement assessment has not been performed.

PURPOSE

To perform an independent evaluation of the AOSpine UCCS.

STUDY DESIGN

Agreement study.

PATIENT SAMPLE

Eighty four patients with upper cervical spine injuries.

OUTCOME MEASURES

Inter-observer agreement; intra-observer agreement.

METHODS

Complete imaging studies of 84 patients with upper cervical spine injuries, including all morphological types of injuries defined by the AOSpine UCCS were selected and classified by six evaluators (from three different countries). The 84 cases were presented to the same raters randomly after a 4-week interval for repeat evaluation. The Kappa coefficient (κ) was used to determine inter- and intra-observer agreement.

RESULTS

The interobserver agreement was almost perfect when considering the fracture site (I, II or III), with κ=0.82 (0.78-0.83), but the agreement according to the site and type level was moderate, κ=0.57 (0.55-0.65). The intra-observer agreement was almost perfect considering the injury, with κ=0.83 (0.78-0.86), while according to site and type was substantial, κ=0.69 (0.67-0.71).

CONCLUSIONS

We observed only a moderate inter-observer agreement using this classification. We believe our results can be explained because this classification attempted to organize many different injury types into a single scheme.

Scientometric Analysis of Publications from 2004-2021 in the Spine Surgery Field: A Latin American Perspective

OBJECTIVE

To determine characteristics of Latin American (LA) productivity in spine surgery published worldwide between 2004 and 2021 compared between periods and global literature.

METHODS

A comprehensive search about LA productivity in the field of spine surgery using the Scopus and PubMed databases was performed in February 2022. The results were limited to articles published in indexed journals from 2004 to 2021.

RESULTS

A total of 1447 publications were identified in the study period. The number of publications has increased across evaluated decades, with 583 between 2004 and 2013 (58.3/year) and 864 between 2014 and 2021 (108/year), and a yearly increase was demonstrated (P = 0.0001). Comparing the most productive year in the first (2012) and last decade (2020), a 1.79-fold increase was demonstrated. Brazil ranked first in productivity (51.14%), followed by Mexico (26.40%) and Argentina (8.64%). Coluna/Columna published the largest number, with 309 articles (21.35%). The top 10 institutions published at least 475 (32.82%) and the most productive was the University of Campinas (Brazil, 74).

CONCLUSIONS

This scientometric study is one of the first regional evaluations worldwide. The number of publications in the spine surgery field in Latin America has continued to increase over evaluated decades from 58.3 per year to 108, and a 1.79-fold increase between the most productive years for each decade. Brazil is still the greatest contributor (51.14%), with Mexico (26.40%) and Argentina (8.64%) as growing contributor countries. Most publications were classified as Level of Evidence 4, and this result reflects the importance of continuous research development in the quality of research for our region.

Correlation Between Cage Positioning and Lumbar Lordosis in Transforaminal Lumbar Interbody Fusion (TLIF)

Objective  The present study evaluates radiographic outcomes and the lumbar lordosis achieved with a transforaminal lumbar interbody fusion (TLIF) arthrodesis technique according to the positioning of an interbody device (cage) in the disc space. Methods  This is a retrospective radiographic analysis of single-level surgical patients with degenerative lumbar disease submitted to a TLIF procedure and posterior pedicle instrumentation. We divided patients into two groups according to cage positioning. For the TLIF-A group, the cages were anterior to the disc space; for the TLIF-P group, cages were posterior to the disc space. Considering the superior vertebral plateau of the lower vertebra included in the instrumentation, cages occupying a surface equal to the anterior 50% of the midline were placed in the TLIF-A group, and those in a posterior position were placed in the TLIF-P group. We assessed pre- and postoperative orthostatic lateral radiographs to obtain the following measures: lumbar lordosis (LL) (angle L1-S1), segmental lordosis (LS) (L4-S1), and segmental lordosis of the cage (SLC). Results  The present study included 100 patients from 2011 to 2018; 44 were males, and 46 were females. Their mean age was 50.5 years old (range, 27 to 76 years old). In total, 43 cages were "anterior" (TLIF-A) and 57 were "posterior" (TLIF-P). After surgery, the mean findings for the TLIF-A group were the following: LL, 50.7°, SL 34.9°, and SLC 21.6°; in comparison, the findings for the TLIF-P group were the following: LL, 42.3° ( p  < 0.01), SL 30.7° ( p  < 0.05), and SLC 18.8° ( p  > 0.05). Conclusion  Cage positioning anterior to the disc space improved lumbar and segmental lordosis on radiographs compared with a posterior placement.

Need of vascular surgeon and comparison of value for anterior lumbar interbody fusion (ALIF) in lateral decubitus: Delphi consensus

BACKGROUND AND PURPOSE

Anterior lumbar approaches are recommended for clinical conditions that require interbody stability, spinal deformity corrections or a large fusion area. Anterior lumbar interbody fusion in lateral decubitus position (LatALIF) has gained progressive interest in the last years. The study aims to describe the current habit, the perception of safety and the perceptions of need of vascular surgeons according to experienced spine surgeons by comparing LatALIF to the standard L5-S1 supine ALIF (SupALIF).

METHODS

A two-round Delphi method study was conducted to assess the consensus, within expert spine surgeons, regarding the perception of safety, the preoperative planning, the complications management and the need for vascular surgeons by performing anterior approaches (SupALIF vs LatALIF).

RESULTS

A total of 14 experts voluntary were involved in the survey. From 82 sentences voted in the first round, a consensus was reached for 38 items. This included the feasibility of safe LatALIF without systematic involvement of vascular surgeon for routine cases (while for revision cases the involvement of the vascular surgeon is an appropriate option) and the appropriateness of standard MRI to evaluate the accessibility of the vascular window. Thirteen sentences reached the final consensus in the second round, whereas no consensus was reached for the remaining 20 statements.

CONCLUSIONS

The Delphi study collected the consensus on several points, such as the consolidated required experience on anterior approaches, the accurate study of vascular anatomy with MRI, the management of complications and the significant reduction of the surgical times of the LatALIF if compared to SupALIF in combined procedures. Furthermore, the study group agrees that LatALIF can be performed without the need for a vascular surgeon in routine cases.

Unstable Thoracolumbar Injuries: Factors Affecting the Decision for Short-Segment vs Long-Segment Posterior Fixation

BACKGROUND

Factors influencing the length of spinal instrumentation have been mostly evaluated in burst fractures, receiving more attention than other unstable thoracolumbar injuries. We aimed to evaluate clinical factors affecting surgical decision-making and associated complications.

METHODS

This was a multicentric retrospective cohort study. Outcomes of patients with AO Spine injury classification types B2, B3, and C operated through an open posterior-only approach were analyzed. Length of instrumentation was correlated with age, type of injury, comorbidities, level of injury, neurological status, and complications.

RESULTS

Among 439 patients, 30.3% underwent short-segment fixation (SSF) and 69.7% underwent long-segment fixation (LSF). Type C injuries were treated with LSF in 89.4% of cases (P < 0.001). On multivariate analysis, age ≤39 years (OR: 2.06), AO spine type B2 (OR: 3.58), and type B3 (OR: 7.48) were statistically significant predictors for SSF, while hypertension (OR: 4.07), upper thoracic injury (OR: 9.48), midthoracic injury (OR: 6.06), and American Spinal Injury Association Impairment Scale A (OR: 3.14) were significantly associated with LSF. Patients with SSF had fewer overall complications (27.1% vs 50.9%, P < 0.001) and were less likely to develop pneumonia (6.0% vs 18.3%, P < 0.001) and urinary tract infections (6.8% vs 16.3%, P < 0.007).

CONCLUSIONS

Unstable thoracolumbar injuries were mostly treated by LSF. Length of instrumentation was affected by the type of spinal injury, location of the injury, and neurological status. SSF was associated with lower rates of early complications than LSF.

CLINICAL RELEVANCE

The decision on the length of fixation in the surgical treatment of unstable thoracolumbar injuries is affected by different factors, and it will impact the rate of postoperative complications.

LEVEL OF EVIDENCE: 3

The impact of stratified hypoalbuminemia and dialysis on morbidity/mortality after posterior spinal fusion surgery: An ACS-NSQIP study

Background:

Preoperative optimization in patients undergoing posterior spinal fusion is essential to limit the number and severity of postoperative complications. Here, we, additionally, evaluated the impact of hypoalbuminemia on morbidity and mortality after posterior spinal fusion surgery.

Methods:

This retrospective analysis was performed using data from a prospective multicentric database (ACSNSQIP:2015–2020) regarding patients undergoing posterior spinal fusions. Factors studied included; baseline demographics and 30-day postoperative complications (i.e., reoperations, readmissions, and mortality rates).

Results:

There were 6805 patients who met the inclusion criteria. They averaged 62 years of age and had an average BMI of 30.2. Within the 30-day postoperative period, 634 (9.3%) sustained complications; 467 (6.9%) were readmitted, 263 (3.9%) required reoperations, and 37 (0.5%) expired. Although multiple preoperative risk factors were analyzed, hypoalbuminemia, severe hypoalbuminemia, and dialysis were the strongest independent risk factors associated with complications (i.e., reoperations, readmissions, and mortality).

Conclusion:

Hypoalbuminemia, severe hypoalbuminemia, and dialysis were significant predictors for morbidity and mortality after posterior spinal fusion surgery.

Reliability Evaluation of the New AO Spine-DGOU Classification for Osteoporotic Thoracolumbar Fractures

OBJECTIVES

To perform an interobserver and intraobserver agreement evaluation of the new AO Spine-DGOU classification system for osteoporotic thoracolumbar fractures (OFc).

METHODS

Complete imaging studies of 97 patients (radiographs, computed tomography scans, and magnetic resonance imaging) with osteoporotic thoracolumbar fractures were selected and classified using the OFc by 6 spine surgeons (3 senior surgeons with more than 15 years of experience and 3 surgeons with less than 15 years). After a 4-week interval, the same cases were presented to the same evaluators in a random sequence for a new classification assessment. The weighted kappa coefficient (wκ) was used to determine the interobserver and intraobserver agreement.

RESULTS

The interobserver agreement was moderate, wκ = 0.59 (95% confidence interval 0.54-0.64). The intraobserver agreement was fair, wκ = 0.35 (95% confidence interval 0.29-0.40). Interobserver agreement slightly improved for junior staff between first and second evaluation, suggesting a learning effect. Better agreement was obtained by senior staff at the interobserver and intraobserver agreement.

CONCLUSIONS

This independent assessment demonstrated that new OFc allows moderate interobserver agreement and fair intraobserver agreement. Further studies are necessary prior to its widespread adoption.

When to Consider Stand-Alone Lateral Lumbar Interbody Fusion: Is There a Role for a Comeback With New Implants?

OBJECTIVE

To perform a comprehensive review of the literature about the role of stand-alone lateral lumbar interbody fusion (LLIF).

METHODS

A MEDLINE review was conducted including studies about stand-alone LLIF for any condition. The opinions of the authors were also considered. Studies that included biomechanical, cadaveric, or clinical aspects of stand-alone cages were revised to obtain data about the pros, cons, and limitations of the technique. Comparative studies with 360° (lateral + posterior) fusions were also analyzed.

RESULTS

A total of 36 studies were identified. After reviewing the abstracts, 18 full articles of interest for the objective of this review were analyzed. Recommendations based on the literature were made. Although most of the recommendations in the literature were about augmentation with pedicle screws, there may be a role for stand-alone LLIF in some particular cases. Specific technical aspects should be considered to reduce the failure rate.

CONCLUSION

Although there might be some specific indications for stand-alone LLIF, it should be considered an exception rather than the rule.

LEVEL OF EVIDENCE: 4

Monitoring and reporting gaps in spine surgery education through an international needs assessment survey

Background A critical step in curriculum development is conducting a needs assessment of learners. In spine surgery, the educational needs of trainees, and especially of practicing surgeons, evolve frequently due to changes in practice, technology, etc. To monitor these changes and adapt the educational offerings, organizations delivering continuing medical education (CME) and continuing professional development (CPD) periodically repeat needs assessments. Methods An international needs assessment in the form of a set of 15 online questions was designed and circulated in 2017 and in 2021 to the AO Spine community of members and registered users to gather input in five main areas: educational needs in spine pathologies and techniques, required improvements in practice, preferences for types of educational offerings, and profiling information. Results We received and analyzed 1,204 responses in English during the main reporting period in the 2017 needs assessment from residents, fellows, and practicing surgeons in orthopedics and neurosurgery, and 1,845 in 2021. Spine surgeons wish to improve their knowledge related to all the common pathologies, with some variability among regions and stage of career. Minimally invasive spine surgery (MISS) was the highest-rated need within surgical techniques in all regions (except North America) and all stages of career. Data show a strong preference for face-to-face courses with hands-on training, high demand for mentorship/fellowship/observership, and solid interest in online and blended education. Conclusions The needs assessment process pointed out general trends but also identified varying needs depending on the local situation and stage of career. For this reason, CME/CPD providers must adapt to the local situation to provide educational offerings that meet learner needs.

Quality Assessment for Reporting Complications and Adverse Events in Spinal Surgery: A Proposed 5-Item Checklist

BACKGROUND

Reporting complications and/or adverse events after spinal surgical procedures enables the estimation of their prevalence and of their impact on patient outcomes. However, the documentation of complications is relatively infrequent and highly heterogeneous. The purpose of this study was to evaluate the quality of complication and adverse event reporting in spinal surgery literature.

METHODS

A systematic review of the literature from 5 international, peer-reviewed, indexed spinal journals was performed. Included studies were published between January and December 2020 and reported the surgical results of spinal procedures. Data on the level of evidence and study design were collected and analyzed as well as whether the studies were single-center or multicenter studies. The quality of complication reports was evaluated through a 5-item checklist, with 5 questions divided into 3 parts: definition, evaluation, and report.

RESULTS

Complications associated with spinal surgical procedures were reported in 292 studies. According to the level of evidence, significantly higher reporting quality was seen in level I and II studies compared with level III and IV studies (P = 0.003). Regarding the 5-item checklist, 49% (143/292) of studies fulfilled the definition section, 16.4% (48/292) fulfilled the evaluation section, and 92% (270/292) fulfilled the report section.

CONCLUSIONS

Overall quality assessment when reporting complications in surgical spinal studies showed that only 13% (38/292) of publications that reported complications as part of the outcomes exhibited all items of the 5-item checklist. Additionally, significantly better reports were observed in level I studies compared with level II-IV studies.

Vertebral augmentation plus short-segment fixation versus vertebral augmentation alone in Kümmell's disease: a systematic review and meta-analysis

Osteoporotic vertebral compression fractures of the thoracolumbar spine can progress to Kümmell's disease, an avascular vertebral osteonecrosis. Vertebral augmentation (VA)-vertebroplasty and/or kyphoplasty-is the main treatment modality, but additional short-segment fixation (SSF) has been recommended concomitant to VA. The aim is to compare clinical and radiological outcomes of VA + SSF versus VA alone. Systematic review, including comparative articles in Kümmell's disease, was performed. This study assessed the following outcome measurements: visual analog scale (VAS), Oswestry Disability Index (ODI), anterior vertebral height (AVH), local kyphotic angle (LKA), operative time, blood loss, length of stay, and cement leakage. Six retrospective studies were included, with 126 patients in the VA + SSF group and 152 in VA alone. Pooled analysis showed the following: VAS, non-significant difference favoring VA + SSF: MD -0.61, 95% CI (-1.44, 0.23), I² 91%, p = 0.15; ODI, non-significant difference favoring VA + SSF: MD -9.85, 95% CI (-19.63, -0.07), I² 96%, p = 0.05; AVH, VA + SSF had a non-significant difference over VA alone: MD -3.21 mm, 95% CI (-7.55, 1.14), I² 92%, p = 0.15; LKA, non-significant difference favoring VA + SSF: MD -0.85°, 95% CI (-5.10, 3.40), I² 95%, p = 0.70. There were higher operative time, blood loss, and hospital length of stay for VA + SSF (p < 0.05), but with lower cement leakage (p < 0.05). VA + SFF and VA alone are effective treatment modalities in Kümmell's disease. VA + SSF may provide superior long-term results in clinical and radiological outcomes but required a longer length of stay.

Minimally Invasive Versus Open Surgery for the Treatment of Types B and C Thoracolumbar Injuries: A PRISMA Systematic Review

BACKGROUND

Thoracic and lumbar spine injuries may require surgical management, particularly AO Spine types B and C injuries. Open reduction and fixation using pedicle screws, with or without fusion and/or decompression, is the gold standard surgical treatment for unstable injuries. Recent advances in instrumentation design have resulted in less-invasive surgeries. However, the literature is sparse about the effectiveness of these procedures for types B and C injuries. The objective is to compare the outcomes of conventional open surgery versus minimally invasive spine surgery (MISS) for the treatment of AO Spine types B and C thoracolumbar injuries.

METHODS

A systematic review of published literature in PubMed, Web of Science, and Scopus was performed to identify studies comparing outcomes achieved with open versus minimally invasive surgery in AO Spine types B and C thoracolumbar injury patients. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used.

RESULTS

Five retrospective case-control studies and 3 prospective studies met selection criteria. In general, most of the studies demonstrated that minimally invasive spine surgery is feasible for types B and C injuries, and associated with potential advantages like reduced blood loss, postoperative pain, and muscle injury, and shorter hospital stays. However, no differences were detected in major outcomes, like neurological status or disability.

CONCLUSIONS

Published literature currently suggests that minimally invasive spine surgery is a valid alternative for treating types B and C thoracolumbar injuries. However, further comparative prospective randomized clinical trials are necessary to establish the superiority of one approach over the other.

LEVEL OF EVIDENCE

3.

COVID-19 Impact Among Spine Surgeons in Latin America

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

The aim of this study was to evaluate the impact of the COVID-19 outbreak in spine surgeons in Latin America.

METHODS

A questionnaire was sent to Latin American spine surgeons from April 4 to 6, 2020. Surgeon characteristics were recorded. The impact of COVID-19 on economic well-being, work, and mental health were also determined. All variables were compared and analyzed.

RESULTS

Two hundred four surgeons answered the complete survey; most of them were male (96.6%), the average age was 47.7 years; 58.8% (n = 120) were orthopedic surgeons and 41.2% (n = 84) were neurosurgeons. The majority of the respondents were from Argentina (59.8%, n = 122), followed by Brazil (17.2%, n = 35), Chile (6.4%, n = 13), and Mexico (5.9%, n = 12). Most of the surgeons reported performing emergency procedures only during the pandemic (76.5%, n = 156). Half used telemedicine or online consultation modalities (54.4%, n = 111). The average concern about the financial situation due to the pandemic was 7.53 in a scale of 1 to 10 (10 being the worst scenario). Twenty-two percent (n = 45) of the surgeons had a score over 10 in the Patient Health Questionnaire (PHQ-9; scores higher than 10 needs referral to confirm depression diagnosis). Young age and neurosurgery as a specialty were associated with higher PHQ-9 scores.

CONCLUSIONS

COVID-19 has an impact in the daily working practice and financial situation of spine surgeons in Latin America. The long-term psychological impact should be taken into consideration to avoid a heavier burden for health care providers.

Partial Sacrectomy for Resection of a Sacral Chordoma: 2-Dimensional Operative Video

Sacral chordomas are infrequent tumors that arise from remnants of the notochord. They are most often found in the sacrum and skull-base.1,2 These lesions rarely metastasize and usually have an indolent and oligosymptomatic clinical course. Chordomas show low sensitivity to standard radiation therapy and chemotherapy. Operative resection with wide resection margins offers the best long-term prognosis, including longer survival and local control.1,3 However, achieving a complete resection with oncological margins may be difficult because of the anatomic complexity of the sacrococcygeal region.4 The main complications of sacral resection include infections, wound closure defects, and anorectal and urogenital dysfunction. The rate of these complications is significantly increased when the tumor involves the S2 level or above. We report the case of a 64-yr-old male who presented with progressive sacrococcygeal pain and a feeling of incomplete evacuation. A heterogeneous, osteolytic lesion was found at the sacrococcygeal region. Full body imaging tests were negative for other lesions. A computed tomography (CT) guided biopsy was made. We usually use the midline approach in case we have to include the needle path in the resection. The pathology confirmed a sacrococcygeal, low-grade chordoma. We decided to perform an en bloc resection. A posterior, partial sacrectomy was planned distal to the S4 level.

Independent Reliability Analysis of a New Classification for Pyogenic Spondylodiscitis

STUDY DESIGN

Diagnostic study, level of evidence III.

OBJECTIVE

Pyogenic spondylodiscitis can cause deformity, neurological compromise, disability, and death. Recently, a new classification of spondylodiscitis based on magnetic resonance imaging was published. The objective of this study is to perform an independent reliability analysis of this new classification.

METHODS

We selected 35 cases from our database of different spine centers in Latin America and from the literature; 8 observers evaluated the classification and graded the scenarios according to the methodological grading of the classification developed by Pola et al. Cases were sent to the observers in a random sequence after 3 weeks to assess intraobserver reliability. The interobserver and intraobserver reliabilities were performed with Fleiss and Cohen statistics, respectively.

RESULTS

The overall Fleiss κ value for interobserver agreement was substantial, with 0.67 (95% CI = 0.43-0.91) in the first reading and 0.67 (95% CI = 0.45-0.89) in second reading for the main types of classification. The Cohen κ value for intraobserver agreement was also substantial, with 0.68 (95% CI = 0.45-0.92). The interobserver agreement analysis for the subtypes of this classification was overall substantial, with 0.60 (95% CI = 0.37-0.83) in the first reading and 0.61 (95% CI = 0.41-0.81) in the second reading. The overall intraobserver agreement for subtypes of the classification was also substantial, with 0.63 (95% CI = 0.34-0.93).

CONCLUSION

The new classification developed by Pola et al showed substantial interobserver and intraobserver agreements. More studies are required to validate the usefulness of this classification especially in clinical practice.

Single-Position Surgery versus Lateral-Then-Prone-Position Circumferential Lumbar Interbody Fusion: A Systematic Literature Review

OBJECTIVE

We sought to compare the outcomes of single-position (SP) circumferential lumbar interbody fusion in lateral decubitus versus dual-position (DP) fusion.

METHODS

A systematic literature review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in PubMed, Web of Science, and Scopus databases to identify comparative studies reporting the outcomes of SP lumbar interbody fusion versus DP. For risk of bias assessment, the ROBINS-I (risk of bias in nonrandomized studies of interventions) tool was used.

RESULTS

Four comparative studies were included from an initial search of 3780 papers. All 4 studies were retrospective cohort studies comparing outcomes of SP versus DP LLIF. A total of 349 patients were operated using SP versus 254 using DP. All studies involved reported operating time, estimated blood loss, length of stay, change in segmental lordosis, and complications. From a general perspective, baseline variables were similar in both groups in all the studies and all reported a significant decrease in operative time and length of stays with SP.

CONCLUSIONS

Literature comparing SP versus lateral-then-prone lumbar fusion shows a tendency toward shorter operating time and hospital stays in SP lumbar fusion while maintaining similar perioperative outcomes.

Reporting Complications in Spinal Surgery-a Systematic Literature Review

BACKGROUND

Many efforts are expended to improve health care quality in the surgical treatment of spinal conditions. However, the prevalence of reporting complications in spinal surgeries is highly heterogeneous, which is partially due to the lack of a universal and comprehensive system.

METHODS

A systematic review of the literature was performed in 5 international and indexed spine journals from January to December 2020. All clinical studies that had surgical procedures in any spinal region were classified according to level of evidence, study design, category of spinal condition, and primary outcome. The prevalence and quality of complication reporting were evaluated through a checklist.

RESULTS

Of 455 articles screened, complications were reported in 64.2% (292 articles). A significant higher prevalence of reports was observed in randomized compared with nonrandomized studies (P < 0.05). In 89 articles, at least 1 classification was used to report complications, with 12 different classification systems employed in the total sample. Timing to record complications was as follows: 47 (16.1%) articles reported complications at 30 days, 31 (10.6%) reported complications at 90 days, and 88 (30.1%) reported complications during all follow-ups. In 126 (43.1%) articles, complications were not mentioned.

CONCLUSIONS

Almost one-third of spine surgical studies did not report complications in their results despite reporting clinical outcomes. The evidence quality of the study was directly related with the reporting of complications. A high heterogeneity regarding complication reporting was seen in the literature.

20 Tips to Avoid and Handle Problems in the Placement of Percutaneous Pedicle Screws

BACKGROUND

Two-dimensional fluoroscopy-guided percutaneous pedicle screw placement is currently the most widely applied instrumentation for minimally invasive treatment of spinal injuries requiring stabilization. Although this technique has advantages over open instrumentation, it also presents new challenges and specific complications. The objective of this study was to provide recommendations developed from the experience of several spinal surgeons at different minimally invasive spine surgery reference centers to solve specific problems and prevent complications during the learning curve of this technique.

METHODS

An AO Spine Latin America minimally invasive spine surgery study group analyzed the most frequent complications and challenges occurring during the placement of >14,000 two-dimensional fluoroscopy-guided percutaneous pedicle screws at different centers over 15 years. Twenty tips considered most relevant to performing this technique, excluding problems directly related to specific brands of instruments, were presented.

RESULTS

The 20 tips included the following: (1) positioning; (2) clean and painless; (3) fewer x-rays; (4) check the clock; (5) beveled tip; (6) transverse-rib-pedicle; (7) double Jamshidi; (8) hammer the Kirschner wire; (9) bent tip; (10) too loose, too tight; (11) new trajectory; (12) manual control; (13) start over; (14) Kirschner wire first; (15) adhesive drape control; (16) bend the rod; (17) lower rods; (18) freehand inner; (19) posterior fusion; (20) revision.

CONCLUSIONS

Implementation of these tips might improve performance of this technique and reduce the complications related to percutaneous pedicle screw placement.

Low Implant Failure Rate of Percutaneous Fixation for Spinal Metastases: A Multicenter Retrospective Study

OBJECTIVE

To evaluate incidence and types of implant failure observed in a series of patients with spinal metastases (SM) treated with minimally invasive stabilization surgery without fusion.

METHODS

In this multicenter, retrospective, observational study, we reviewed the files of patients >18 years old who underwent surgery for SM using percutaneous spinal stabilization without fusion with a minimum 3-month follow-up. The following variables were included: demographics, clinical findings, prior radiation history, SM location, epidural spinal cord compression scale, Spinal Instability Neoplastic Scale, neurological examination, and surgery-related data. Primary outcome measure was implant failure rate, as observed in patients' last computed tomography scan. Multivariable analysis was performed to identify baseline factors and factors associated with implant failure.

RESULTS

Analysis included 72 patients. Mean age of patients was 62 years, 39 patients were men, and 75% of patients had an intermediate Spinal Instability Neoplastic Scale score. Tumor separation surgery was performed in 48.6% of patients. Short instrumentation was indicated in 54.2% of patients. Three patients (4.2%) experienced implant failure (2 screw loosening, 1 screw cut-out); none of them required revision surgery. In 73.6% of cases, survival was >6 months. No significant predictors of failure were identified in the multivariate analysis.

CONCLUSIONS

A low implant failure rate was observed over the short and medium term, even when short instrumentations without fusion were performed. These findings suggest that minimally invasive stabilization surgery without fusion may be an effective and safe way to treat complicated SM.

Time to Surgery for Unstable Thoracolumbar Fractures in Latin America-A Multicentric Study

OBJECTIVE

We sought to identify delays for surgery to stabilize unstable thoracolumbar fractures and the main reasons for them across Latin America.

METHODS

We reviewed the charts of 547 patients with type B or C thoracolumbar fractures from 21 spine centers across 9 Latin American countries. Data were collected on demographics, mechanism of trauma, time between hospital arrival and surgery, type of hospital (public vs. private), fracture classification, spinal level of injury, neurologic status (American Spinal Injury Association impairment scale), number of levels instrumented, and reason for delay between hospital arrival and surgical treatment.

RESULTS

The sample included 403 men (73.6%) and 144 women (26.3%), with a mean age of 40.6 years. The main mechanism of trauma was falls (44.4%), followed by car accidents (24.5%). The most frequent pattern of injury was B2 injuries (46.6%), and the most affected level was T12-L1 (42.2%). Neurologic status at admission was 60.5% intact and 22.9% American Spinal Injury Association impairment scale A. The time from admission to surgery was >72 hours in over half the patients and over a week in >25% of them. The most commonly reported reasons for surgical delay were clinical instability (22.9%), lack of operating room availability (22.7%), and lack of hardware for spinal instrumentation (e.g., screws/rods) (18.8%).

CONCLUSIONS

Timing for surgery in this sample of unstable fractures was over 72 hours in more than half of the sample and longer than a week in about a quarter. The main reasons for this delay were clinical instability and lack of economic resources. There is an apparent need for increased funding for the treatment of spinal trauma patients in Latin America.

Access to Technology and Education for the Development of Minimally Invasive Spine Surgery Techniques in Latin America

OBJECTIVE

To evaluate access to the technologies and education needed to perform minimally invasive spine surgery (MISS) in Latin America.

METHODS

We designed a questionnaire to evaluate surgeons' practice characteristics, access to different technologies, and training opportunities for MISS techniques. The survey was sent to members and registered users of AO Spine Latin from January 6-20, 2020. The major variables studied were nationality, specialty (orthopedics or neurosurgery), level of hospital (primary, secondary, tertiary), number of surgeries performed per year by the spine surgeon, types of spinal pathologies commonly managed, and number of MISS performed per year. Other variables involved specific access to different technologies: intraoperative fluoroscopy, percutaneous screws, cages, tubular retractors, microscopy, intraoperative computed tomography, neuronavigation imaging, and bone morphogenetic protein. Finally, participants were asked about main obstacles to performing MISS and their access to education on MISS techniques in their region.

RESULTS

The questionnaires were answered by 306 members of AO Spine Latin America across 20 different countries. Most answers were obtained from orthopedic surgeons (57.8%) and those with over 10 years of experience (42.4%). Most of the surgeons worked in private practice (46.4%) and performed >50 surgeries per year (44.1%), but only 13.7% performed >50 MISS per year, mainly to manage degenerative pathologies (87.5%). Most surgeons always had access to fluoroscopy (79%). Only 26% always had access to percutaneous screws, 24% to tubular retractors, 34.3% to cages (anterior lumbar interbody fusion, lateral lumbar interbody fusion, or transforaminal lumbar interbody fusion), and 43% to microscopy. Regarding technologies, 71% reported never having access to navigation, 83% computed tomography, and 69.3% bone morphogenetic protein. The main limitations expressed for widely used MISS technologies were the high implant costs (69.3%) and high navigation costs (49.3%). Most surgeons claimed access to online education activities (71%), but only 44.9% reported access to face-to-face events and 28.8% to hands-on activities, their limited access largely because the courses were expensive (62.7%) or few courses were available on MISS in their region (51.3%).

CONCLUSIONS

Most surgeons in Latin America have limited resources to perform MISS, even in private practice. The main constraints are implant costs, access to technologies, and limited face-to-face educational opportunities.

Barriers of neurophysiology monitoring in spine surgery: Latin America experience

Background:

Intraoperative neurophysiological monitoring (IOM) has become valuable in spine surgery. Unfortunately, it is not always available in many spine centers, especially in developing countries. Our aim was to evaluate the accessibility and barriers to IOM in spine surgery in Latin America.

Methods:

We designed a questionnaire to evaluate the characteristics of surgeons and their opinions on the usefulness of IOM for different spine operations. The survey was sent to 9616 members and registered users of AO Spine Latin America (AOSLA) from August 1, 2019, to August 21, 2019. Major variables studied included nationality, years of experience, specialty (orthopedics or neurosurgery), level of complexity of the hospital, number of spine surgeries performed per year by the spine surgeon, the types of spinal pathologies commonly managed, and how important IOM was to the individual surgeon. General questions to evaluate use included accessibility, limitations of IOM usage, management of IOM changes, and the legal value of IOM. The results were analyzed and compared between neurosurgeon and orthopedics, level of surgeon experience, and country of origin.

Results:

Questionnaires were answered by 200 members of AOSLA from 16 different countries. The most common responses were obtained from orthopedic surgeons (62%), those with more than 10 years of practice (54%); majority of surgeons performed more than 50 spine surgeries per year (69%) and treated mainly spine degenerative diseases (76%). Most surgeons think that IOM has a real importance during surgeries (92%) and not just a legal value. Although surgeons mostly considered IOM essential to scoliosis surgery in adolescents (70%), thoracolumbar kyphosis correction (68%), and intramedullary tumors (68%), access to IOM was limited to 57% for economic reasons. Of interest, in 64% of cases, where IOM was available and significant change occurred, the actual operative procedures were significantly altered.

Conclusion:

Despite the fact that 68% of spine surgeons believe IOM to be indispensable for complex spine surgery, cost remains the main barrier to its use/availability in Latin America.

Perception of complications by spine surgeons

Background:

The perception of major versus minor complications may vary according to surgeons, institutions, and different specialties. Here, we analyzed the geographic distribution of the different types/severities of the most frequent complications in spinal surgery, and assessed how the perception of spine surgeons about postoperative complications differed.

Methods:

We performed a cross-sectional study using a questionnaire, we developed to encompass different clinical scenarios of surgeons’ perceptions of spine surgery complications. The survey involved the members of AOSpine Latin America (LA) (January 28, 2017–March 15, 2017). The main variables studied included: specialty, age, years of experience, country, individual surgeon’s perception of different clinical scenarios, and the surgeon’s classification of complications for each scenario (e.g., major, minor, or none). Our results from LA were then analyzed and compared to North American (NA) responses.

Results:

Orthopedic surgeons represented about 58.2% (n = 412) of the 708 questionnaires answered. Of interest, 45.6% (n = 323) of those responding had >10 years of experience. The countries analyzed included Brazil (31.5%), Mexico (17.5%), Argentina (14.4%), Colombia (8.0%), and Venezuela (7.6%). Four of the 11 scenarios showed consensus in the results (e.g., average being over 82.5%). A tendency toward consensus was present in 45.4% of the clinical cases, while two out of 11 clinical cases did not present a consensus among surgeons. Of interest, the perception of complications was similar between cohorts (LA 85% vs. NA 80%).

Conclusion:

Significant consensus in the perception of complications was observed in most of the analyzed scenarios for both LA and NA. However, within the LA data, responses to different clinical scenarios varied.

Total subaxial reconstruction

Cervical deformity, particularly kyphosis, is frequently encountered in surgical practice. While many cases are asymptomatic, some patients may have significant pain and disability. We provide a brief review of the pathophysiology of cervical deformity and the technical aspects of deformity correction in the cervical spine. Anterior techniques reviewed here include anterior cervical discectomy and fusion (ACDF), anterior corpectomy and fusion (ACCF) and anterior osteotomy (ATO). Posterior techniques include laminectomy and fusion, posterior column osteotomy (PCO) and pedicle subtraction osteotomy (PSO). This is a fast-evolving field as our understanding of cervical deformity matures and longer-term surgical outcomes are available.

Teaching Training and Surgical Education in Minimally Invasive Surgery (MIS) of the Spine: What Are the Best Teaching and Learning Strategies for MIS? Do We Have Any Experience and Data?

STUDY DESIGN

Literature review and transversal study.

OBJECTIVE

Advances in new technologies give the surgeons confidence to manage complex spine conditions with a lower morbidity rate. This has changed the expectations of patients and medical payers and foreshadows the shift now underway: the use of minimally invasive techniques. The ethical considerations of learning directly on patients require a change in the education and training programs.

METHODS

The education paradigm has changed, and surgical training on minimally invasive surgery of the spine (MISS) techniques should follow a "curriculum." The assessment of skill proficiency while learning the MISS techniques must be measurable to objectively show the performance gained over time and the changes that should be performed during training. Different strategies include "ex vivo" and "in vivo" training.

RESULTS

We have worked on a curriculum in which the participants can perceive the growth in their knowledge through the different educational opportunities. There are 3 levels: basic, advanced, and masters.

CONCLUSIONS

We developed an educational curriculum for MISS rationale and techniques, that showed to be effective and interesting in our region.

[Post-op paraspinal atrophy: Does the approach matter?]

Objetivo:

comparar la magnitud de la atrofia muscular postoperatoria que producen tres abordajes en fusiones lumbares segmentarias para patología degenerativa. (línea media vs Wiltse vs MIS TLIF).

Material y métodos:

se realizó un estudio observacional, transversal, multicéntrico, descriptivo y retrospectivo de una serie de pacientes operados por patología degenerativa lumbar. Analizamos 45 pacientes (24 mujeres), con una edad media de 58.7 años, operados en 5 centros quirúrgicos entre 2015 y 2018. Se realizó una fusión instrumentada de un nivel, desde L3 hasta S1 (7 casos L3-L4, 25 casos L4-L5 y 13 casos L5-S1). 15 casos fueron realizados por abordajes por línea media, 15 por abordaje de Wiltse y 15 MIS TLIF. Todos fueron estudiados con Resonancia Magnética preoperatoria y con un mínimo de 6 meses luego de la cirugía (media de 14.6 meses). Estas fueron analizadas por 3 observadores especialistas en cirugía de columna. Se tomaron 2 variables para comparar el grado de atrofia entre pre y postoperatorio: área de sección transversal (AST) de músculo multifidus (MM) y erectores espinales (EE) y grado de infiltración grasa (IG) mediante la clasificación visual de Kjaer. Los análisis realizados fueron ejecutados utilizando el programa estadístico RStudio (versión 1.1.383) y se compararon valores de P obtenidos mediante la suma de rangos de Wilcoxon.

Resultados:

no se encontraron diferencias significativas entre los distintos abordajes en relación a la atrofia del MM. La comparación de P para AST de los EE mostró diferencias entre MIS TLIF vs línea media (P 0.018) y de línea media vs Wiltse (P 0.027).

Conclusión:

los abordajes mínimamente invasivos utilizados para descompresión y artrodesis monosegmentaria lumbar tuvieron más impacto sobre la atrofia muscular en los EE que en MM. Estudios randomizados y controlados serían de utilidad para validar los resultados de este trabajo.

Thoracic spine dislocation in Gorham-Stout Syndrome: Case report and literature review

Background

The Gorham-Stout syndrome (GSS), also known as phantom bone disease, is a rare bone condition of unknown etiology. Involvement of the spine is described in <50 cases in the literature. Here, we report a case of thoracic spine fracture dislocation in a young female who was known to have GSS.

Case Description

A 23-year-old female developed a left spontaneous hemothorax 10 years previously along with left ribs lytic lessions. Pleural and rib biopsies diagnosed angiomatosis and the clinical diagnosis of GSS was established. Following a minor trauma, she presented with a Frankel B deficit attributed to a T3-T4 fracture dislocation with severe spinal cord compression. The patient underwent halo traction with CT. Following reduction, decompression and C5 to T8 with instrumented fusion (posterior only), she neurologically improved to Frankel D, 2 years postoperatively.

Conclusion

Although GSS is a rare condition in the spine, it may lead to gross instability and catastrophic vertebral fracture/dislocation with paraparesis. Acute spinal cord decompression with stabilization may be warranted to achieve neurological improvement.