Hemispheric asymmetries in cortical grey matter of gyri and sulci in modern human populations from South America.

Structural asymmetries of brain regions associated with lateralised functions have been extensively studied. However, there are fewer morphometric analyses of asymmetries of the gyri and sulci of the entire cortex. The current study assessed cortical asymmetries in a sample of healthy adults (N = 175) from an admixed population from South America. Grey matter volume and surface area of 66 gyri and sulci were quantified on T1 magnetic resonance images. The departure from zero of the differences between left and right hemispheres (L-R), a measure of directional asymmetry (DA), the variance of L-R, and an index of fluctuating asymmetry (FA) were evaluated for each region. Significant departures from perfect symmetry were found for most cortical gyri and sulci. Regions showed leftward asymmetry at the population level in the frontal lobe and superior lateral parts of the parietal lobe. Rightward asymmetry was found in the inferior parietal, occipital, frontopolar, and orbital regions, and the cingulate (anterior, middle, and posterior-ventral). Despite this general pattern, several sulci showed the opposite DA compared to the neighbouring gyri, which remarks the need to consider the neurobiological differences in gyral and sulcal development in the study of structural asymmetries. The results also confirm the absence of DA in most parts of the inferior frontal gyrus and the precentral region. This study contributes with data on populations underrepresented in the databases used in neurosciences. Among its findings, there is agreement with previous results obtained in populations of different ancestry and some discrepancies in the middle frontal and medial parietal regions. A significant DA not reported previously was found for the volume of long and short insular gyri and the central sulcus of the insula, frontomarginal, transverse frontopolar, paracentral, and middle and posterior parts of the cingulate gyrus and sulcus, gyrus rectus, occipital pole, and olfactory sulcus, as well as for the volume and area of the transverse collateral sulcus and suborbital sulcus. Also, several parcels displayed significant variability in the left-right differences, which can be partially attributable to developmental instability, a source of FA. Moreover, a few gyri and sulci displayed ideal FA with non-significant departures from perfect symmetry, such as subcentral and posterior cingulate gyri and sulci, inferior frontal and fusiform gyri, and the calcarine, transverse collateral, precentral, and orbital sulci. Overall, these results show that asymmetries are ubiquitous in the cerebral cortex.

Association between lumbar intervertebral vacuum phenomenon severity and posterior paraspinal muscle atrophy in patients undergoing spine surgery.

PURPOSE: Intervertebral vacuum phenomenon (IVP) and paraspinal muscular atrophy are age-related changes in the lumbar spine. The relationship between both parameters has not been investigated. We aimed to analyze the correlation between IVP and paraspinal muscular atrophy in addition to describing the lumbar vacuum severity (LVS) scale, a new parameter to estimate lumbar degeneration. METHODS: We analyzed patients undergoing spine surgery between 2014 and 2016. IVP severity was assessed utilizing CT scans. The combination of vacuum severity on each lumbar level was used to define the LVS scale, which was classified into mild, moderate and severe. MRIs were used to evaluate paraspinal muscular fatty infiltration of the multifidus and erector spinae. The association of fatty infiltration with the severity of IVP at each lumbar level was assessed with a univariable and multivariable ordinal regression model. RESULTS: Two hundred and sixty-seven patients were included in our study (128 females and 139 males) with a mean age of 62.6 years (55.1-71.2). Multivariate analysis adjusted for age, BMI and sex showed positive correlations between LVS-scale severity and fatty infiltration in the multifidus and erector spinae, whereas no correlation was observed in the psoas muscle. CONCLUSION: IVP severity is positively correlated with paraspinal muscular fatty infiltration. This correlation was stronger for the multifidus than the erector spinae. No correlations were observed in the psoas muscle. The lumbar vacuum severity scale was significantly correlated with advanced disc degeneration with vacuum phenomenon.

Severe Intervertebral Vacuum Phenomenon is Associated With Higher Preoperative Low Back Pain, ODI, and Indication for Fusion in Patients With Degenerative Lumbar Spondylolisthesis.

STUDY DESIGN: Retrospective study of prospective collected data. OBJECTIVE: To analyze the association between intervertebral vacuum phenomenon (IVP) and clinical parameters in patients with degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: IVP is a sign of advanced disc degeneration. The correlation between IVP severity and low back pain in patients with degenerative spondylolisthesis has not been previously analyzed. METHODS: We retrospectively analyzed patients with degenerative spondylolisthesis who underwent surgery. Vacuum phenomenon was measured on computed tomography scan and classified into mild, moderate, and severe. A lumbar vacuum severity (LVS) scale was developed based on vacuum severity. The associations between IVP at L4/5 and the LVS scale, preoperative and postoperative low back pain, as well as the Oswestry Disability Index was assessed. The association of IVP at L4/5 and the LVS scale and surgical decision-making, defined as decompression alone or decompression and fusion, was assessed through univariable logistic regression analysis. RESULTS: A total of 167 patients (52.7% female) were included in the study. The median age was 69 years (interquartile range 62-72). Overall, 100 (59.9%) patients underwent decompression and fusion and 67 (40.1%) underwent decompression alone. The univariable regression demonstrated a significantly increased odds ratio (OR) for back pain in patients with more severe IVP at L4/5 [OR=1.69 (95% CI 1.12-2.60), P =0.01]. The univariable regressions demonstrated a significantly increased OR for increased disability with more severe L4/L5 IVP [OR=1.90 (95% CI 1.04-3.76), P =0.04] and with an increased LVS scale [OR=1.17 (95% CI 1.02-1.35), P =0.02]. IVP severity of the L4/L5 were associated with higher indication for fusion surgery. CONCLUSION: Our study showed that in patients with degenerative spondylolisthesis undergoing surgery, the severity of vacuum phenomenon at L4/L5 was associated with greater preoperative back pain and worse Oswestry Disability Index. Patients with severe IVP were more likely to undergo fusion.

Association Between Osteoarthritis Burden and Intervertebral Disk Degeneration in Patients Undergoing Lumbar Spine Surgery for Degenerative Lumbar Spondylolisthesis.

STUDY DESIGN: A retrospective analysis of prospectively collected data. OBJECTIVE: To assess the association between intervertebral disk degeneration and hip and knee osteoarthritis (OA) in patients with degenerative lumbar spondylolisthesis. BACKGROUND: The co-occurrence of hip OA and degenerative spinal pathologies was first described as the "hip-spine syndrome" and has also been observed in knee OA. It remains unclear whether both pathologies share an underlying connection beyond demographic factors. MATERIALS AND METHODS: Intervertebral disk degeneration was classified by the Pfirrmann Classification and intervertebral vacuum phenomenon. Intervertebral vacuum phenomenon was classified into mild (1 point), moderate (2 points), and severe (3 points) at each level and combined into a lumbar vacuum score (0-15 points). Similarly, a lumbar Pfirrmann grade was calculated (5-25 points). Patients with previous hip or knee replacement surgery were classified as having an OA burden. We used multivariable regression to assess the association between OA and disk degeneration, adjusted for age, body mass index, and sex. RESULTS: A total of 246 patients (58.9% female) were included in the final analysis. Of these, 22.3% had OA burden. The multivariable linear regression showed an independent association between OA burden and lumbar vacuum (ß = 2.1, P <0.001) and Pfirrmann grade (ß = 2.6, P <0.001). Representing a 2.1 points higher lumbar vacuum and 2.6 points higher lumbar Pfirrmann grade after accounting for demographic differences. CONCLUSIONS: Our study showed that OA burden was independently associated with the severity of the intervertebral disk degeneration of the lumbar spine. These findings give further weight to a shared pathology of OA of large joints and degenerative processes of the lumbar spine. LEVEL OF EVIDENCE: 3.

Guillain-Barré Syndrome and COVID-19 Vaccine: A Multicenter Retrospective Study of 46 Cases.

ABSTRACT: In the context of the global vaccination campaign against COVID-19, several cases of postvaccinal Guillain-Barré syndrome (GBS) were reported. Whether a causal relationship exists between these events has yet to be established. We investigated the clinical and electromyographic characteristics of patients who developed GBS after COVID-19 vaccination and compare these with findings in patients with GBS, without a history of recent vaccination. We included 91 cases between March 2020 and March 2022, treated at 10 referral hospitals of Buenos Aires, Argentina. Of these, 46 had received vaccination against COVID-19 within the previous month. Although Medical Research Council sum-scores were similar in both groups (median 52 vs. 50; P = 0.4), cranial nerve involvement was significantly more frequent in the postvaccination group (59% vs. 38%; P = 0.02), as was bilateral facial paralysis (57% vs. 24%; P = 0.002). No differences were found in clinical or neurophysiological phenotypes, although 17 subjects presented the variant of bilateral facial palsy with paresthesias (11 vs. 6; P = 0.1); nor were significant differences observed in length of hospital stay or mortality rates. Future vaccine safety monitoring and epidemiology studies are essential to demonstrate any potential causal relationship between these events.

Association between Modic changes and intervertebral vacuum phenomenon severity in patients undergoing percutaneous cement discoplasty.

BACKGROUND: Modic changes and intervertebral vacuum phenomenon (IVP) are considered spinal degenerative changes. The correlation between Modic and IVP has not been analyzed in the literature. PURPOSE: To analyze the correlation between IVP severity, Modic changes, and subchondral sclerosis across the lumbar spine in patients with lumbar degeneration. MATERIAL AND METHODS: This is a retrospective study analyzing patients who underwent percutaneous cement discoplasty at a single institution between 2015 and 2020. Preoperative magnetic resonance imaging and computed tomography scans were analyzed to make the measurements. Modic type and grade as well as severity of IVP were preoperatively measured. The association between Modic type, grade, subchondral sclerosis, and the presence of IVP was analyzed. RESULTS: In total, 110 patients (mean age = 77.03 ± 7.1 years) were finally included in the study. Per level correlation analysis showed a significant positive association between IVP and Modic type, IVP and Modic grade, and IVP and subchondral sclerosis. Moreover, subchondral sclerosis was significantly associated with Modic type and grade. CONCLUSION: Our study showed a significant positive correlation among Modic changes, IVP, and subchondral sclerosis throughout the lumbar spine. Our findings support the theory that endplate degeneration parameters are associated with the presence and severity of IVP.

NORHA: A NORmal Hippocampal Asymmetry Deviation Index Based on One-Class Novelty Detection and 3D Shape Features.

Radiologists routinely analyze hippocampal asymmetries in magnetic resonance (MR) images as a biomarker for neurodegenerative conditions like epilepsy and Alzheimer's Disease. However, current clinical tools rely on either subjective evaluations, basic volume measurements, or disease-specific models that fail to capture more complex differences in normal shape. In this paper, we overcome these limitations by introducing NORHA, a novel NORmal Hippocampal Asymmetry deviation index that uses machine learning novelty detection to objectively quantify it from MR scans. NORHA is based on a One-Class Support Vector Machine model learned from a set of morphological features extracted from automatically segmented hippocampi of healthy subjects. Hence, in test time, the model automatically measures how far a new unseen sample falls with respect to the feature space of normal individuals. This avoids biases produced by standard classification models, which require being trained using diseased cases and therefore learning to characterize changes produced only by the ones. We evaluated our new index in multiple clinical use cases using public and private MRI datasets comprising control individuals and subjects with different levels of dementia or epilepsy. The index reported high values for subjects with unilateral atrophies and remained low for controls or individuals with mild or severe symmetric bilateral changes. It also showed high AUC values for discriminating individuals with hippocampal sclerosis, further emphasizing its ability to characterize unilateral abnormalities. Finally, a positive correlation between NORHA and the functional cognitive test CDR-SB was observed, highlighting its promising application as a biomarker for dementia.

Frontal Aslant Tract and Its Role in Language: A Journey Through Tractographies and Dissections.

BACKGROUND: The frontal aslant tract (FAT) is a bilateral tract located within each frontal lobe. It connects the supplementary motor area in the superior frontal gyrus with the pars opercularis in the inferior frontal gyrus. There is a new and broader conceptualization of this tract called the extended FAT (eFAT). The eFAT tract role is believed to be related to several brain functions, including verbal fluency as one of its main domains. METHODS: Tractographies were performed by using DSI Studio software on a template of 1065 healthy human brains. The tract was observed in a three-dimensional plane. The Laterality Index was calculated based on the length, volume, and diameter of fibers. A t test was performed to verify the statistical significance of global asymmetry. The results were compared with cadaveric dissections performed according to the Klingler technique. An illustrative case enlightens the neurosurgical application of this anatomic knowledge. RESULTS: The eFAT communicates the superior frontal gyrus with the Broca area (within the left hemisphere) or its contralateral homotopic area within the nondominant hemisphere. We measured the commisural fibers, traced cingulate, striatal, and insular connections and showed the existence of new frontal projections as part of the main structure. The tract did not show a significant asymmetry between the hemispheres. CONCLUSIONS: The tract was successfully reconstructed, focusing on its morphology and anatomic characteristics.

Intervertebral vacuum phenomenon - prevalence and severity CT-scan analysis in patients older than 50 years: a retrospective cohort study.

BACKGROUND: Chronic low back pain secondary to degenerative changes in the spine is a common cause of disability, and disc degeneration is one of the most frequent imaging findings. Intervertebral vacuum phenomenon (IVP) is usually observed in advanced degeneration. Recently, this phenomenon has gained interest due to a relatively new surgical technique called percutaneous discoplasty, aimed at treating low back pain secondary to degenerative disc disease in elderly patients. PURPOSE: To analyze the prevalence and related factors of the vacuum phenomenon in adult patients. MATERIAL AND METHODS: A retrospective cohort study was performed of patients who underwent abdominal computed tomography (CT) for non-spine-related reasons. Age, body mass index, smoking, and CT-based characteristics as presence of IVP, subchondral sclerosis, and facet joint degeneration at the lumbar spine from L1 to the sacrum were included in order to determine the prevalence of the vacuum phenomenon in this population and establish a relationship between this condition and patient demographics and other signs of spine degeneration, such as sclerosis and facet joint disease. RESULTS: A total of 238 patients were included in the study (114 men, 124 women; mean age = 75.6 ± 12.3 years. In total, 91 (38%) patients had at least one level of IVP; 59 (25%) patients exhibited subchondral sclerosis, and 235 (98%) facet joint degeneration. Among risk factors, age, smoking, and subchondral sclerosis were significantly associated with the presence of vacuum. CONCLUSION: IVP was present in 38% of participants. Risk factors associated with vacuum were age, smoking, and subchondral sclerosis.

Brain mapping of emotional prosody in patients with drug-resistant temporal epilepsy: An indicator of plasticity.

INTRODUCTION: Emotional prosody, a suprasegmental component of language, is predominantly processed by right temporo-frontal areas of the cerebral cortex. In temporal lobe epilepsy (TLE), brain disturbances affecting prosody processing frequently occur. This research assesses compensatory brain mechanisms of prosody processing in refractory TLE using fMRI. METHODS: Patients with focal unilateral epilepsy, right (RTLE) (N = 19), left (LTLE) (N = 19), and healthy controls (CTRL) (N = 20) were evaluated during a prosody decoding fMRI task. The stimuli consisted in spoken numbers with different tones of voice (joy, fear, anger, neutral and silent trials). Participants were instructed to label the emotion with a keypad. "Joy" was removed from the analysis due to a high degree of variability. A lateralization index (LI) was used to see individual differences in the interhemispheric activations of each participant. RESULTS: Behaviorally, The LTLE and RTLE groups did not differ significantly from each other neither from CTRL. In Negative Emotions versus Baseline contrast, the whole sample analysis showed extensive activations in bilateral superior temporal gyrus, bilateral precentral and post-central gyrus, right putamen, and left cerebellar vermis. Compared to the LTLE and CTRL, RTLE activated similar areas, but to a lesser extent. The LI analysis revealed significant differences in hemispheric laterality of the temporal lobe and the parietal lobe between RTLE compared to LTLE and CTRL, being the RTLE group lateralized towards the left, unlike the other two groups. DISCUSSION: The LI indicated that, since the CTRL and the LTLE groups recruited putative prosodic regions, the RTLE lateralized prosody processing towards the left, recruiting contralateral nodes, homotopic to the putative areas of the prosody. Considering that the groups did not differ in prosody task performance, the findings suggest that, in the RTLE group, alternative brain nodes were recruited for the task, demonstrating plasticity.

Influence of accessory sulci of the frontoparietal operculum on gray matter quantification.

Introduction: The perisylvian region is the cortical core of language and speech. Several accessory sulci have been described in this area, whose presence could modify the results of the automatic quantification of gray matter by popularly used software. This study aimed to assess the expression of accessory sulci in the frontoparietal operculum (FPO) and to evaluate their influence on the gray matter volume estimated by an automatic parcellation of cortical gyri and sulci. Methods: Brain MRI scans of 100 healthy adult volunteers were visually analyzed. The existence of the triangular and diagonal sulci, and the number of accessory sulci in the frontoparietal operculum, were assessed on T1 images. Also, the gray matter volume of gyri and sulci was quantified by an automatized parcellation method. Interhemispheric differences in accessory sulci were evaluated with Chi-square and Wilcoxon paired tests. The effects of the hemisphere, sex, age, total intracranial volume, and accessory sulci on morphometric variables were assessed by linear models. Results: These sulci were found in more than half of the subjects, mostly in the left hemisphere, and showed a significant effect on the gray matter content of the FPO. In particular, the volume of the inferior frontal sulcus, pars opercularis of the inferior frontal gyrus, horizontal ramus of the lateral sulcus, angular gyrus, and postcentral gyrus showed a significant influence on the presence of accessory sulci. Discussion: The prevalence of tertiary sulci in the FPO is high, although their meaning is not yet known. Therefore, they should be considered to reduce the risk of misclassifications of normal variation.

Three-Dimensional Anatomy of the Anterior Commissure: A Tractography and Anatomical Study.

BACKGROUND: The anterior commissure (AC) is one of the main commissural fibers of the brain. The commissural fibers are involved in bilateral integration and coordination of any normal brain activity. The AC is an important interhemispheric structure that forms a bidirectional communication channel between the frontal, temporal, parietal, and occipital lobes bilaterally. METHODS: In the present study, we focused on describing the morphology, relationships, and distribution of the AC using diffusion spectrum imaging-based fiber tracking. The tractograms were compared with the findings from gross anatomical dissection of the AC of adult brains. RESULTS: Our findings suggest that the AC found using tracking methods is larger than that found by dissection. CONCLUSIONS: The use of tractography added extensions to the main AC structure.

Accuracy of intraoperative neuromonitoring during percutaneous cement discoplasty.

Introduction: Percutaneous cement discoplasty is a minimally invasive procedure to treat low back pain due to advanced degenerative disc disease in elderly patients. Complications of this procedure has been described such as infection, vertebral fracture, cement leakage and nerve injury. Intraoperative neuromonitoring is used to detect the latter. The objective of this study was to assess the usefulness of neuromonitoring during discoplasty to detect new neurological compromise. Methods: 100 consecutive patients were included in this retrospective study, (30 males and 70 females, mean age of 76.3 ± 5.71 years) with mechanical low back pain who underwent percutaneous cement discoplasty. Results: Sensitivity to detect neurological injury was 82% (CI 95% 66-98), specificity was of 99% (CI 95%98-100) with a positive predictive value of 0.95 (CI 95% 85-100) and a negative predictive value of 0.97 (CI 95% 95-99). In 5 patients neurological compromise was not detected by neuromonitoring. Discussion: Our study showed high sensitivity and specificity of neuromonitoring to detect neurological irritation during percutaneous discoplasty. Intraoperative neuromonitoring resulted an effective assistance during this minimally invasive procedure.

Introducción: La Discoplastia percutánea con cemento es un procedimiento mínimamente invasivo para tratar el dolor lumbar debido a la enfermedad degenerativa del disco avanzada en pacientes ancianos. Se han descrito complicaciones de este procedimiento como infección, fractura vertebral, fuga de cemento y lesión nerviosa. El neuromonitoreo intraoperatorio se utiliza para detectar este último. El objetivo de este estudio fue evaluar la utilidad del neuromonitoreo intraoperatorio durante la Discoplastia para detectar un nuevo compromiso neurológico. Material y métodos: se incluyeron en este estudio retrospectivo 100 pacientes consecutivos (30 varones y 70 mujeres, edad media 76,3 ± 5,71 años) con lumbalgia mecánica sometidos a Discoplastia percutánea con cemento. Resultados: La sensibilidad para detectar lesión neurológica fue del 82% (IC 95% 66-98), la especificidad fue del 99% (IC 95% 98-100) con un valor predictivo positivo de 0,95 (IC 95% 85-100) y un valor predictivo negativo. valor predictivo de 0,97 (IC 95% 95-99). En 5 pacientes no se detectó compromiso neurológico mediante neuromonitoreo. Discusión: Nuestro estudio mostró una alta sensibilidad y especificidad del neuromonitoreo intraoperatorio para detectar irritación neurológica durante la discoplastia percutánea. El neuromonitoreo intraoperatorio resultó una ayuda eficaz durante este procedimiento mínimamente invasivo.

Variaciones anatómicas de la arteria hepática: patrones vasculares observados en 140 hígados de donante cadavérico / Anatomical variations of the hepatic artery: vascular patterns observed in 140 cadaveric donor livers

RESUMEN: El objetivo de este trabajo es analizar las variantes de la arteria hepática observadas en hígados de donantes cadavéricos empleados para trasplante ortotópico de hígado en nuestra población. Se efectuó un estudio retrospectivo de una cohorte de 140 trasplantes entre junio del año 2011 y enero del año 2021. La anatomía vascular arterial de los injertos hepáticos fue clasificada de acuerdo a la descripción de Hiatt. Variante clásica de la arteria hepática - Tipo I: 62 casos (65,7 %). Variante no clásica de la arteria hepática: 48 casos (34,3 %), correspondientes a: Tipo II: 12 casos (8,6 %), Tipo III: 18 casos (12,9 %), Tipo IV: 7 casos (5 %), Tipo V: 10 casos (7,1 %). No se encontró ningún caso de variante Tipo VI. Se halló 1 caso (0,7 %) no descrito en esta clasificación correspondiente a una arteria hepática izquierda accesoria que se originaba de la aorta. El conocimiento preciso de las variaciones más prevalentes, y también de las menos frecuentes, es fundamental para los procedimientos quirúrgicos que se realizan en el abdomen superior.

SUMMARY: The purpose of this article is to analyze the hepatic artery variations observed from the use of cadaveric donor livers for orthotopic transplantation among our population. A retrospective study of a liver transplant cohort including 140 donor livers was conducted between June 2011 and January 2021. The vascular arterial anatomy of the transplanted livers was classified according to Hiatt's classification system. Classic hepatic artery variant: Type I: 62 cases (65.7 %). Non-classic hepatic artery variants: 48 cases (34.3 %), corresponding to: Type II: 12 cases (8.6 %), Type III: 18 cases (12.9 %), Type IV: 7 cases (5 %), Type V: 10 cases (7.1 %). No case of Type VI variant was identified. One case (0.7 %) not included in Hiatt's classification was found, corresponding to an accessory left hepatic artery originating from the aorta. Precise knowledge regarding the most prevalent variations, as well as those that are the least common, is fundamental to upper abdominal surgical procedures.

Percutaneous Cement Discoplasty for Degenerative Low Back Pain with Vacuum Phenomenon: A Multicentric Study with a Minimum of 2 Years of Follow-Up.

BACKGROUND: To report clinical results after percutaneous cement discoplasty (PCD) in a multicentric case series with a minimum of 2 years of follow-up. METHODS: Between December 2014 and January 2019, 180 patients with low back pain and advanced degeneration were treated with percutaneous discoplasty in 2 centers. The inclusion criteria were as follows: patients 65 years or older, with mechanical low back pain with or without spinal stenosis, who did not respond to conservative management. Patients were divided into 3 groups: group 1: patients without previous spine surgeries who underwent PCD, group 2: patients with previous spine surgeries who underwent PCD, and group 3: patients with/without previous surgery who underwent PCD plus decompression surgery. Clinical and radiological analyses were performed as well as complication and readmission rates. RESULTS: A total of 156 patients (74% female; mean age, 75.8 ± 5.7 years; mean body mass index, 29.9 ± 5.2) were included in our study. Overall preoperative visual analog score (VAS) and Oswestry Disability Index (ODI) were 7.8 ± 0.9 and 68.1 ± 9.6, respectively. At 2 years of follow-up, mean VAS improvement was 3.56 (95% confidence interval: 3.92-3.20; P < 0.0001) and mean ODI improvement was 17.18 (95% confidence interval: 19.52-14.85; P < 0.0001), showing a significant and sustained improvement in both scores. In addition, 84% of patients reached both VAS and ODI minimum important clinical difference at the final follow-up. Finally, 5.7% of patients suffered major complications 30 days postoperatively. CONCLUSIONS: PCD showed significant improvement of VAS and ODI scores at 2 years of follow-up with relatively low rate of complications.

Percutaneous cement discoplasty for the treatment of advanced degenerative disk disease in elderly patients.

PURPOSE: The authors describe a percutaneous technique to treat advanced degenerative disk disease in elderly patients. METHOD: A step-by-step technical description based on our experience in selected cases. RESULT: Postoperative imaging results are presented as well as indications and recommendations. CONCLUSION: Percutaneous discoplasty can result as an alternative minimal invasive strategy for the treatment of advanced degenerative disk disease.

Development of a New Therapy-Oriented Classification of Intervertebral Vacuum Phenomenon With Evaluation of Intra- and Interobserver Reliabilities.

STUDY DESIGN: Diagnostic study, level of evidence III. OBJECTIVES: Low back pain is a common cause of disability among elderly patients. Percutaneous discoplasty has been developed as a tool to treat degenerative disease when conservative management is not successful. Indications for this procedure include low back pain and the presence of vacuum phenomenon. The objective of this study was to describe a new classification of vacuum phenomenon based on computed tomography scan in order to improve the indications for percutaneous discoplasty. METHODS: We developed a classification of vacuum phenomenon based on computed tomography scan images. We describe 3 types of vacuum based on the relationship between vacuum and the superior/inferior endplates and 2 subtypes based on the presence of significant subchondral sclerosis. A validation study was conducted selecting 10 orthopedic residents with spine surgery training to analyze 25 vacuum scenarios. Inter- and intraobserver reliabilities were assessed through the Fleiss's and Cohen's kappa statistics, respectively. RESULTS: The overall Fleiss's κ value for interobserver reliability was 0.85 (95% CI 0.82-0.86) in the first reading and 0.93 (95% CI 0.92-0.95) in the second reading. Cohen's κ for intraobserver reliability was 0.88 (95% CI 0.77-0.99). CONCLUSION: The new classification has shown almost perfect inter- and intraobserver reliabilities for grading the vacuum phenomenon and could be an important tool to improve the indications for percutaneous cement discoplasty.