Quantifying Lumbar Foraminal Volumetric Dimensions: Normative Data and Implications for Stenosis-Part 2 of a Comprehensive Series.

INTRODUCTION: Lumbar foraminal stenosis (LFS) occurs primarily due to degenerative changes in older adults, affecting the spinal foramina and leading to nerve compression. Characterized by pain, numbness, and muscle weakness, LFS arises from structural changes in discs, joints, and ligaments, further complicated by factors like inflammation and spondylolisthesis. Diagnosis combines patient history, physical examination, and imaging, while management ranges from conservative treatment to surgical intervention, underscoring the need for a tailored approach. MATERIALS AND METHODS: This multicenter study, conducted over six years at a tertiary hospital, analyzed the volumetric dimensions of lumbar foramina and their correlation with nerve structures in 500 patients without lumbar pathology. Utilizing high-resolution MRI with a standardized imaging protocol, eight experienced researchers independently reviewed the images for accurate measurements. The study emphasized quality control through the calibration of measurement tools, double data entry, validation checks, and comprehensive training for researchers. To ensure reliability, interobserver and intraobserver agreements were analyzed, with statistical significance determined by kappa statistics and the Student's t-test. Efforts to minimize bias included blinding observers to patient information and employing broad inclusion criteria to mitigate referral and selection biases. The methodology and findings aim to enhance the understanding of normal lumbar foramina anatomy and its implications for diagnosing and treating lumbar conditions. RESULTS: The study's volumetric analysis of lumbar foramina in 500 patients showed a progressive increase in foraminal volume from the L1/L2 to the L5/S1 levels, with significant enlargement at L5/S1 indicating anatomical and biomechanical complexity in the lumbar spine. Lateral asymmetry suggested further exploration. High interobserver and intraobserver agreement levels (ICC values of 0.91 and 0.95, respectively) demonstrated the reliability and reproducibility of measurements. The patient cohort comprised 58% males and 42% females, highlighting a balanced gender distribution. These findings underscore the importance of understanding foraminal volume variations for lumbar spinal health and pathology. CONCLUSION: Our study significantly advances spinal research by quantifying lumbar foraminal volumes, revealing a clear increase from the L1/L2 to the L5/S1 levels, indicative of the spine's adaptation to biomechanical stresses. This provides clinicians with a precise tool to differentiate between pathological narrowing and normal variations, enhancing the detection and treatment of lumbar foraminal stenosis. Despite limitations like its cross-sectional design, the strong agreement in measurements underscores the method's reliability, encouraging future research to further explore these findings' clinical implications.

Integrating Augmented Reality in Spine Surgery: Redefining Precision with New Technologies.

INTRODUCTION: The integration of augmented reality (AR) in spine surgery marks a significant advancement, enhancing surgical precision and patient outcomes. AR provides immersive, three-dimensional visualizations of anatomical structures, facilitating meticulous planning and execution of spine surgeries. This technology not only improves spatial understanding and real-time navigation during procedures but also aims to reduce surgical invasiveness and operative times. Despite its potential, challenges such as model accuracy, user interface design, and the learning curve for new technology must be addressed. AR's application extends beyond the operating room, offering valuable tools for medical education and improving patient communication and satisfaction. MATERIAL AND METHODS: A literature review was conducted by searching PubMed and Scopus databases using keywords related to augmented reality in spine surgery, covering publications from January 2020 to January 2024. RESULTS: In total, 319 articles were identified through the initial search of the databases. After screening titles and abstracts, 11 articles in total were included in the qualitative synthesis. CONCLUSION: Augmented reality (AR) is becoming a transformative force in spine surgery, enhancing precision, education, and outcomes despite hurdles like technical limitations and integration challenges. AR's immersive visualizations and educational innovations, coupled with its potential synergy with AI and machine learning, indicate a bright future for surgical care. Despite the existing obstacles, AR's impact on improving surgical accuracy and safety marks a significant leap forward in patient treatment and care.

Acute back pain - Role of injection techniques and surgery: WFNS spine committee recommendations.

Objective: Lower back pain is a significant cause of morbidity, and despite a range of interventions available, there is a lack of consensus on the most efficacious treatments. The aim of this systematic review is to formulate a list of recommendations for the role of spinal injections and surgery in the treatment of acute back pain. Methods: A systematic literature search from 2012 to 2022 was conducted on Pubmed, Medline, and Cochrane Central Register of Controlled Trials for papers focusing on the role of injections and surgery for the management of acute lower back pain. Inclusion criteria included randomised controlled trials, as well as prospective and retrospective studies reporting primary outcomes (pain improvement (VAS score) and back-specific functional status) and secondary outcomes (post-procedure complications). These data were reviewed, presented, and voted on by an expert panel consisting of 14 attending spine surgeons from 14 countries at the consensus meeting of the World Federation of Neurosurgical Societies (WFNS) Spine Committee. A two-round consensus-based Delphi method was used to generate consensus, and topics with >66% agreement were categorized as having reached consensus. Results: 100 studies met inclusion criteria. Of these, 20 were selected by the committee for full text review and presented at the consensus meeting. The committee voted on 8 statements and achieved consensus on the following 7 statements: (1) Epidural steroid injections (ESIs) show significant benefit to discogenic back pain; (2) A lateral approach is superior to a midline approach for ESIs; (3) Short-term (<1 week) effect of ESIs is similar between steroids; (4) ESIs have a variety of potential complications; (5) CT or fluoroscopy guidance can be used for lumbar medial branch blocks; (6) Lumbar medial branch radiofrequency ablations can be performed on patients with recurrent pain after a successful ESI, and (7) Acute lower back pain is usually self-limiting, resolves in <6 weeks, and does not require surgical intervention. Conclusion: Given significant treatment heterogeneity, we provide the latest, evidence-based recommendations for management of acute lower back pain. ESIs are effective at short-term pain relief, and surgical intervention should be reserved for patients failing conservative measures.

Role of surgery in primary lumbar disk herniation: WFNS spine committee recommendations.

Objective: To provide the most up-to-date recommendations on the role of surgery in first-time lumbar disk herniations (LDH) in order to standardize surgical management. Methods: We performed a literature search in PubMed, Scopus, and Embase from 2012 to 2022 using the following keywords: "lumbar disk herniation AND surgery". Our initial search yielded 2610 results, which were narrowed down to 283 papers after standardized screening critera were applied. The data from these 283 papers were presented and discussed at two international meetings of the World Federation of Neurosurgical Societies (WFNS) Spine Committee, where the Delphi method was employed and ten spine experts voted on five final consensus statements. Results: and Conclusions: The WFNS Spine Committee's guidelines cover four main topics: (1) role and timing of surgery in first-time LDH; (2) role of minimally invasive techniques in LDH; (3) extent of disk resection in LDH surgery; (4) role of lumbar fusion in the context of LDH. Surgery for LDH is recommended for failure of conservative treatment, cauda equina syndrome, and progressive neurological impairment, including severe motor deficits. In the latter cases, early surgery is associated with faster recovery and may improve patient outcomes. Minimally invasive techniques have short-term advantages over open procedures, but there is insufficient evidence to make a recommendation for or against the choice of a specific surgical procedure. Sequestrectomy and standard microdiscectomy demonstrated similar clinical results in terms of pain control, recurrence rate, functional outcome, and complications at short and medium-term follow-up. Lumbar fusion is not recommended as a routine treatment for first-time LDH, although it may be considered in specific patients affected by chronic axial pain or instability.

Lumbar disc herniation: Prevention and treatment of recurrence: WFNS spine committee recommendations.

Objective: This review aims to formulate the most current evidence-based recommendations on the epidemiology, prevention, and treatment of recurrent lumbar disc herniation (LDH). Methods: We performed a systematic literature search in PubMed, Medline, and Google Scholar databases from 2012 to 2022 using the keywords "lumbar disc recurrence." Screening criteria resulted in 57 papers, which were summarized and presented at two international consensus meetings of the World Federation of Neurosurgical Societies (WFNS) Spine Committee. The 57 papers covered the following topics: (1) Definition and incidence of recurrence after lumbar disc surgery; (2) Prediction of recurrence before primary surgery; (3) Prevention of recurrence by surgical measures; (4) Prevention of recurrence by postoperative measures; (5) Treatment options for recurrent disc herniation; (6) The outcomes of recurrent disc herniation surgery. We utilized the Delphi method and voted on eight final consensus statements. Results and conclusion: Recurrence after disc herniation surgery may be considered a surgical complication, its incidence is approximately 5% and is different from overall re-operation incidence. There are multiple risk factors predicting LDH recurrence, including smoking, younger age, male gender, obesity, diabetes, disc degeneration, and presence of lumbosacral transitional vertebrae. The level of lumbar discectomy surgery and the amount of disc material removed do not correlate with recurrence rate. Minimally invasive discectomies may have higher recurrence rates, especially during the surgeon's learning period. However, the experience of the surgeon is not related to recurrence. High-quality studies are needed to determine if activity restriction, weight loss, smoking cessation, and muscle-strengthening exercises after primary surgery can help prevent recurrence of LDH.The best treatment option for recurrent disc herniation is still being discussed. While complications of minimally invasive techniques may be lower than open discectomy, outcomes are similar. Fusion should only be considered when spinal instability and/or spinal deformity are present. Clinical outcomes and patient satisfaction after recurrent disc herniation surgery are inferior to those after initial discectomy.

Factors affecting return to work following endoscopic lumbar foraminal stenosis surgery: A single-center series.

Background: This study evaluates the factors affecting the return to work of endoscopic surgery for lumbar foraminal stenosis (LFS), including symptoms, functional status, complications, and reoperation rates. Methods: The authors' retrospective cohort study included 100 consecutive patients (50 males and 50 females) diagnosed with LFS who underwent endoscopic surgery at Trotsky National Research Center of Surgery between January 2018 and December 2021. Results: There were no significant differences in age and preoperative visual analog scale and Oswestry disability index scores between the male and female groups, time to return to work for different patient groups after undergoing endoscopic lumbar foraminotomy (ELF). However, patients with more severe stenosis and comorbidities may take longer to recover. Confounding factors were patient age, preoperative physical function, and job requirements. Conclusion: This study confirms that study ELF can effectively improve symptoms associated with lumbar radiculopathy, as well as back pain, and improve patients' quality of life. Comorbidity, smoking status, and complications prolong the time to return to work following ELF surgery compared to healthy subjects.

Glioblastoma multiforme at internal auditory canal.

Background: Glioblastomas are the most common adult primary brain tumor present supratentorially. The presence of true extra-axial GBM infratentorially, especially in the internal auditory canal, is extremely rare with only three cases reported previously in the literature. We report the fourth case of primary internal auditory canal/cerebellopontine angle (CPA) glioblastoma which initially mimicked vestibular schwannoma on the basis of its location and presentation. Case Description: A 65-year-old male presented with headache, vertigo, and progressive right ear deafness for 5 months. His preoperative magnetic resonance imaging findings were consistent with vestibular schwannoma. Maximum safe resection (near total) was done. The final histopathology report showed glioblastoma multiforme. Conclusion: As per our knowledge, this is the fourth reported case of an extra-axial VIII cranial nerve glioblastoma located in internal auditory canal. Hence, despite being very rare, they should be considered as a differential in tumors at CPA.

Vertebral augmentation in osteoporotic spine fractures: WFNS Spine Committee recommendations.

INTRODUCTION: The aim of this study was to formulate the WFNS Spine Committee guidelines on indications, outcomes, and complications of vertebral augmentation in osteoporotic spine fractures. EVIDENCE ACQUISITION: Computerized literature was searched from 2010 to 2021 using keywords "vertebral augmentation," "osteoporotic fracture," "technique," "surgery," "complication," and "outcome." PubMed yielded 92 articles whereas Google scholar resulted in 120 articles. 29 articles were studied in detail. The studies comprised of seventeen RCT's, two prospective non-randomized studies, three retrospective studies, and seven systematic reviews. The statements were produced to reach a consensus in two separate meetings of WFNS Spine Committee. The statements were voted and reached a positive or negative consensus using Delphi method. EVIDENCE SYNTHESIS: Drafted statements on "Vertebral Augmentation in osteoporotic Spine Fractures" were voted upon by expert panelists in Virtual WFNS Spine Committee Consensus Meetings conducted on January 11, 2021, and February 13, 2021. Statements reaching positive consensus provided the basis for the WFNS guidelines regarding vertebral augmentation in osteoporotic spine fractures. CONCLUSIONS: WFNS Spine Committee recommendations on vertebral augmentation in osteoporotic spine fractures are summarized in this article. Vertebral augmentation is superior to conservative treatment for vertebral osteoporotic fractures but has conflicting results on comparison with placebo. Both vertebroplasty and kyphoplasty are equally effective. Most of the studies regarding the efficacy of vertebral augmentation procedures to reduce pain have been largely inconclusive. It is suggested that further high quality, better designed randomized controlled studies are required to establish the role of vertebral augmentation in spine osteoporotic compression fractures.

Decompression and fusion surgery for osteoporotic vertebral fractures: WFNS spine committee recommendations.

Osteoporotic vertebral fractures (OVF) are common due to aging populations. Their clinical management remains controversial. Although conservative approaches are sufficient in most cases, there are certain conditions where decompression or fusion surgery are necessary. This manuscript aimed to clarify the indications and types of surgeries for OVF. A Medline and Pubmed search spanning the period between 2010 and 2020 was performed using the key words "osteoporotic vertebral fractures and decompression surgery" and "osteoporotic vertebral fractures and fusion surgery." In addition, we reviewed up-to-date information on decompression and fusion in osteoporotic vertebral fracture (OVF) to reach an agreement in two consensus meetings of the World Federation of Neurosurgical Societies (WFNS) Spine Committee that was held in January and February 2021. The Delphi Method was utilized to improve the validity of the questionnaire. A total of 19 studies examining decompression and fusion surgery in OVF were reviewed. Literature supports the statement that decompression and fusion surgery are necessary for progressive neurological deficits after OVF. The Spine Section of the German Society for Orthopedics and Trauma (DGOU) Classification revealed that it might help make surgical decisions. We also noted that in patients planning to undergo surgery to correct significant kyphosis after OVF, several techniques, including multilevel fixation, cement augmentation, preservation of sagittal balance, and avoiding termination at the apex of kyphosis are necessary to prevent complications. Additionally, it became clear that there is no consensus to choose the type of open surgery (anterior, posterior, combined, using cement or bone or vertebral body cage, the levels, and kind of instrumentation). The current literature indicated that implant failure in the osteoporotic spine is a common complication, and many techniques have been described to prevent implant failure in the osteoporotic spine. However, the superiority of one method over another is unclear. Open surgery for osteoporotic vertebral fractures should be considered if neurologic deficits and significant painful kyphosis. The apparent indications of surgery and most ideal surgical technique for OVF remain unclear in the literature; therefore, the decision must be individualized.

Benchmarking of Neurosurgery Training in Pakistan.

INTRODUCTION: Neurosurgery is a challenging field of surgery. A neurosurgeon has to be trained with the finest skills, knowledge, and competencies necessary to provide high-quality patient care. Maintaining postgraduate training standards is a challenge in Pakistan due to low budget allocation to the health sector. This study aims to assess the difference in parameters among different institutes in different sectors and provinces offering neurosurgery training in Pakistan. METHODS: A nationwide survey was conducted by the Neurosurgery Department at Liaquat National Hospital Karachi, from November 2019 to February 2020. Data were collected through a questionnaire from neurosurgery trainees from all over the country. The questionnaire was divided into the following sections: Sociodemographics and infrastructure of training site, clinical skills training and exposure, knowledge-based education, and workload. The data were kept confidential and institutional names were not inquired or disclosed. RESULTS: The response rate was 85.3% (151/177), with more males (80%) than females. The total number of trainees was higher in government than private institutions (P < 0.005). The frequency (P = 0.030) and number of trainees (P < 0.005) inducted per cycle was more among government institutions. Participation in international conferences was higher among trainees in private sector (P = 0.006). The frequency of clinics was significantly higher in private institutions (P < 0.005), though the number of patients seen per clinic was lower than in government sector (P < 0.005). At a provincial level, there was a significant difference in gender distribution (P = 0.020), total number of trainees (P < 0.005), number of residents per induction (P < 0.005), frequency of mortality and morbidity meetings (P < 0.005), morning meetings (P < 0.005), number of calls per week (P < 0.005), number of workshops attended (P < 0.005), exposure to radiation (P = 0.003), frequency of outpatient departments (OPDs) attended per week (P = 0.002), and number of patients seen per OPD (P 0.02). CONCLUSION: This study reported variability in the quality of neurosurgery training programs within public and private sector with even greater differences between the four provinces of Pakistan. We recommend continuous assessments and re-accreditation of these training programs through subject experts and health-care educationists to improve the quality of training programs; hence the quality of service and patient care.

The Challenges in Neurosurgery Training in a Third World Country.

BACKGROUND: Neurosurgery in Pakistan is an advanced field with significant challenges. The training program tests one's endurance, knowledge, empathy, and dedication. The training structure in Pakistan consists of 5 years, of which 2 years are spent in general surgery followed by 3 years of dedicated neurosurgery. This study aimed to conduct a survey to address the quality of neurosurgery training in Pakistan so that its strengths and deficiencies could be identified, recommendations could be made, and actions could be taken toward improvement. METHODS: A nationwide survey was conducted of neurosurgery residents from all over Pakistan. An e-mail invitation was sent to 177 neurosurgery residents certified by the College of Physicians and Surgeons Pakistan from 22 institutes in all provinces of Pakistan. The questionnaire was divided into the following sections: sociodemographics of participants, infrastructure of training site, clinical skills training and exposure, and knowledge-based education. Data were collected through Google Forms and analyzed using statistical software. RESULTS: A total of 151 residents responded to the survey. More than half of the institutes had >10 neurosurgery residents in their department (59.6%). More than half of the residents did not attend any international conference during their residency (51%). More than one fourth of the residents did not participate in any hands-on workshop during their residency tenure. CONCLUSIONS: The neurosurgical training program in Pakistan requires updating of the curriculum with better implementation. These data will help the College of Physicians and Surgeons Pakistan in standardizing neurosurgical training across Pakistan to improve competence among trainees.

Kyphosis After Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations.

Thoracolumbar fractures change the biomechanics of the spine. Load distribution causes kyphosis by the time. Treatment of posttraumatic kyphosis is still controversial. We reviewed the literature between 2010 and 2020 using a search with keywords "thoracolumbar fracture and kyphosis." We removed osteoporotic fractures, ankylosing spondylitis fractures, non-English language papers, case reports, and low-quality case series. Up-to-date information on posttraumatic kyphosis management was reviewed to reach an agreement in a consensus meeting of the World Federation of Neurosurgical Societies (WFNS) Spine Committee. The first meeting was conducted in Peshawar in December 2019 with WFNS Spine Committee members' presence and participation. The second meeting was a virtual meeting via the internet on June 12, 2020. We utilized the Delphi method to administer the questionnaire to preserve a high degree of validity. We summarized 42 papers on posttraumatic kyphosis. Surgical treatment of thoracolumbar kyphosis due to unstable burst fractures can be done via a posterior only approach. Less blood loss and reduced surgery time are the main advantages of posterior surgery. Kyphosis angle for surgical decision and fusion levels are controversial. However, global sagittal balance should be taken into consideration for the segment that has to be included. Adding an intermediate screw at the fractured level strengthens the construct.

Surgical Techniques for Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations.

To formulate the specific guidelines for the recommendation of thoracolumbar fracture regarding surgical techniques and nonfusion surgery. WFNS (World Federation of Neurosurgical Societies) Spine Committee organized 2 consensus meeting. For nonfusion surgery and thoracolumbar fracture, a systematic literature search in PubMed and Google Scholar database was done from 2010 to 2020. The search was further refined by excluding the articles which were duplicate, not in English or were based on animal or cadaveric subjects. After thorough shortlisting, only 50 articles were selected for full review in this consensus meeting. To generate a consensus, the levels of agreement or disagreement on each item were voted independently in a blind fashion through a Likert-type scale from 1 to 5. The consensus was achieved when the sum for disagreement or agreement was ≥ 66%. Each consensus point was clearly defined with evidence strength, recommendation grade, and consensus level provided. A magnitude of prospective papers were analyzed to formulate consensus on various surgical techniques that can be employed to address different types of thoracolumbar fractures. Surgical treatment of thoracolumbar fractures can be a better option over the nonoperative approach, especially for those who cannot tolerate months in an orthosis or cast, such as those with multiple extremity injuries, skin lesions, obesity, and so forth. It generally allows early mobilization, less hospital stay, reduced pulmonary complications, and better correction of sagittal balance. Current available literature fails to demonstrate any statistically significant benefit of fusion surgery over nonfusion in thoracolumbar fractures.

Incidence and Epidemiology of Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations.

This review aims to search the epidemiology and incidence rates of thoracolumbar spine fractures. A systematic review of the literature of the last 10 years gave 586 results with "incidence," and 387 results with "epidemiology," of which 39 papers were analyzed. The review results were discussed and voted in 2 consensus meetings of the WFNS (World Federation of Neurosurgical Societies) Spine Committee. Out of 39 studies, 15 studies have focused on thoracolumbar trauma, remaining 24 studies have looked at all spine trauma. Most were retrospective in nature; few were prospective and multicenter. Some studies have focused on specific injuries. The annual incidence of TL fractures is about 30/100,000 inhabitants including osteoporotic fractures. There is a trend to increase the fractures in elderly population especially in developed countries, while an increase of motor vehicle accidents in developing countries. The mortality rate among male elderly patients is relatively high. The incidence of thoracolumbar spine fractures is increasing because of low-velocity falls in the elderly population. The main reasons are falls and traffic accidents. Learning the regional differences and some special forms of trauma such as extreme sports, war, and gunshot injuries will help the prevention of the thoracolumbar spine fractures.

Indications for Nonsurgical Treatment of Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations.

Thoracolumbar spine is the most injured spinal region in blunt trauma. Literature on the indications for nonoperative treatment of thoracolumbar fractures is conflicting. The purpose of this systematic review is to clarify the indications for nonsurgical treatment of thoracolumbar fractures. We conducted a systematic literature search between 2010 to 2020 on PubMed/MEDLINE, and Cochrane Central. Up-to-date literature on the indications for nonoperative treatment of thoracolumbar fractures was reviewed to reach an agreement in a consensus meeting of WFNS (World Federation of Neurosurgical Societies) Spine Committee. The statements were voted and reached a positive or negative consensus using the Delphi method. For all of the questions discussed, the literature search yielded 1,264 studies, from which 54 articles were selected for full-text review. Nine studies (4 trials, and 5 retrospective) evaluating 759 participants with thoracolumbar fractures who underwent nonoperative/surgery were included. Although, compression type and stable burst fractures can be managed conservatively, if there is major vertebral body damage, kyphotic angulation, neurological deficit, spinal canal compromise, surgery may be indicated. AO type B, C fractures are preferably treated surgically. Future research is necessary to tackle the relative paucity of evidence pertaining to patients with thoracolumbar fractures.

Atypical sellar cyst: A rare case.

BACKGROUND: Sellar cysts are common in neurosurgery. Around 90% of these are diagnosed as pituitary adenomas. The other 10% are nonadenomatous, inflammatory, infective, metastatic, or cystic in nature. Some rare cysts include dermoid, epidermoid, colloid, and arachnoid. They all have different histological features. The case we present demonstrates a unique cyst with features that are not previously documented. CASE DESCRIPTION: A 60-year-old female presented to the neurosurgical department complaining of blurring of vision and severe headache for more than ½ year. Imaging was done which revealed a bony erosive lesion in the region of sella. Magnetic resonance imaging with contrast showed high signals with no contrast enhancement. A clear diagnosis could not be made based on radiology. Surgery was done and sample was sent for histopathology. Based on histopathological report findings, a diagnosis of benign atypical sellar cyst was made. Post procedure, the patient recovered and was discharged. CONCLUSION: Sellar cysts present similarly. They are differentiated based on their histological features. The sellar cyst we encountered had features different from the ones already described in the literature.

Fusion Surgery for Lumbar Spinal Stenosis: WFNS Spine Committee Recommendations.

Lumbar spine stenosis represents a complex degenerative pathology that has been a subject of significant dispute when it comes to fusion. A review of the literature from 2008 to 2019 was performed on the role of fusion in the treatment of lumbar spinal stenosis using PubMed, Ovid Medline, Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews. Using the key words "lumbar spinal stenosis," "lumbar fusion," "lumbar decompression," and "lumbar pedicle screw fixation," the search revealed 490 papers. Of these, only Level 1 or Level 2 evidence papers were selected, leading to only 3 randomized controlled trials (RCTs) that were analyzed. None of the good-quality studies (RCTs) performed so far have proven any clinical benefit of adding fusion to degenerative lumbar spine decompression. The effect of spinal instability on the outcome following decompression remains controversial. At present, no unanimous criteria exist among the RCTs to identify what constitutes true instability. Fusion for instability or stenosis alone remains controversial, and the results are unconvincing. At this point, the issue expands to not only lumbar degenerative diseases but spinal fractures and lumbar isthmic spondylolisthesis. We thereby present the consensus of the World Federation of Neurosurgical Societies Spine Committee, which formulated the indications for lumbar spine fusion in degenerative lumbar stenosis.

Mobility-Preserving Surgery for Lumbar Spinal Stenosis: WFNS Spine Committee Recommendations.

BACKGROUND: Although decompression is the basis of surgical treatment for lumbar spinal stenosis (LSS), under various circumstances instrumented fusion is performed as well. The rationale for mobility-preserving operations for LSS is preventing adjacent segment disease (ASD). We review the rationale for mobility preservation in ASD and discuss related topics such as indications for fusion and the evolving role of minimally invasive approaches to lumbar spine decompression. Our focus is on systematic review and consensus discussion of mobility-preserving surgical methods as related to surgery for LSS. METHODS: Groups of spinal surgeons (members of the World Federation of Neurosurgical Societies Spine Committee) performed systematic reviews of dynamic fixation systems, including hybrid constructs, and of interspinous process devices; consensus statements were generated based on the reviews at 2 voting sessions by the committee several months apart. Additional review of background data was performed, and the results summarized in this review. RESULTS: Decompression is the basis of surgical treatment of LSS. Fusion is an option, especially when spondylolisthesis or instability are present, but indications remain controversial. ASD incidence reports show high variability. ASD may represent the natural progression of degenerative disease in many cases. Older age, poor sagittal balance, and multilevel fusion may be associated with more ASD. Dynamic fixation constructs are treatment options that may help prevent ASD.