Facet Tropism/Inclination and Its Association with Intervertebral Disc Herniation in the Lumbar Spine - A Radiological Evaluation / Tropismo/inclinação facetária e sua associação com hérnia de disco intervertebral na região lombar da coluna - Uma avaliação radiológica

Abstract Objective To assess the role of facet tropism (FT) in intervertebral disc prolapse. Methods A total 98 patients with lower back pain were included in the study. Magnetic resonance imaging scans were performed and analyzed. The angles of the right and left facets were measured on the axial section. Patients without disc prolapse at the L3-L4, L4-L5 and L5-S1 levels act as controls for those with disc prolapse at the same levels. A statistical analysis was also performed. Results The incidence of FT at the L3-L4 level was of 85.2% in patients with disc herniation (n= 27), and of 56.3% in the control group, which was statistically significant (p= 0.008). Similarly, at the L4-L5 level, incidence of FT among cases and controls was of 71.4% (n= 35) and 52.4% respectively (p= 0.066). At the L5-S1 the incidence was of 66% and 51% among cases and controls respectively (p= 0.13). Conclusion We found a positive association between FT and disc herniation at the L3-L4 level, but no association at the L4-L5 and L5-S1 levels.

Resumo Objetivo Avaliar o papel do tropismo facetário (TF) no prolapso discal intervertebral. Métodos Um total de 98 pacientes com dor lombar foram incluídos no estudo. Exames de ressonância magnética foram realizados e analisados, e os ângulos das facetas direita e esquerda foram medidos na seção axial. Os pacientes sem prolapso discal nos níveis L3-L4, L4-L5 e L5-S1 atuam como controles para aqueles com prolapso nos mesmos níveis. Fez-se também uma análise estatística. Resultados A incidência de TF no nível L3-L4 foi de 85,2% em pacientes com hérnia discal (n= 27), e de 56,3% no grupo controle, o que foi estatisticamente significativo (p= 0,008). Da mesma forma, a incidência de TF no nível L4-L5 entre casos e controles foi de 71,4% (n= 35) e 52,4%, respectivamente (p= 0,066). No nível L5-S1, a incidência foi de 66% e 51% nos caso e nos controles, respectivamente (p= 0,13). Conclusão Encontramos associação positiva entre TF e hérnia de disco no nível L3-L4, mas nenhuma associação nos níveis L4-L5 e L5-S1.

Study of nonlinear viscoelastic mechanical properties of degenerated intervertebral discs / Estudio de las propiedades mecánicas viscoelásticas no lineales de discos intervertebrales degenerados

SUMMARY: Biomechanical factors are important factors in inducing intervertebral disc degeneration, in this paper, the nonlinear viscoelastic mechanical properties of degenerated intervertebral discs were analyzed experimentally. Firstly, the loading and unloading curves of intervertebral discs before and after degeneration at different strain rates were compared to analyze the changes of their apparent viscoelastic mechanical properties; The internal stress/strain distribution of the disc before and after degeneration was then tested by combining digital image technology and fiber grating technology. The results show that the intervertebral disc is strain-rate- dependent whether before or after degeneration; The modulus of elasticity and peak stress of the degenerated disc are significantly reduced, with the modulus of elasticity dropping to 50 % of the normal value and the peak stress decreasing by about 55 %; Degeneration will not change the distribution of the overall internal displacement of the intervertebral disc, but has a greater impact on the superficial and middle AF; The stress in the center of the nucleus pulposus decreases, and the stress in the outer AF increases after degeneration. Degeneration has a great impact on the nonlinear viscoelastic mechanical properties of intervertebral disc, which has reference value for the mechanism, treatment and prevention of clinical degenerative diseases.

RESUMEN: Los factores biomecánicos son importantes en la inducción de la degeneración del disco intervertebral. En este estudio se analizaron experimentalmente las propiedades mecánicas viscoelásticas no lineales de los discos intervertebrales degenerados. En primer lugar se compararon las curvas de carga y descarga de los discos intervertebrales, antes y después de la degeneración, a diferentes velocidades de deformación para analizar los cambios aparentes de sus propiedades mecánicas viscoelásticas. La distribución interna de tensión/deformación del disco antes y después de la degeneración se probó luego combinando tecnología de imagen digital y tecnología de rejilla de fibra. Los resultados mostraron que el disco intervertebral depende de la velocidad de deformación antes o después de la degeneración; El módulo de elasticidad y la tensión máxima del disco degenerado se reducen significativamente, cayendo el módulo de elasticidad al 50 % del valor normal y la tensión máxima disminuyendo en aproximadamente un 55 %; La degeneración no cambiará la distribución del desplazamiento interno general del disco intervertebral, pero tiene un mayor impacto en la FA superficial y media; El estrés en el centro del núcleo pulposo disminuye y el estrés en el FA externo aumenta después de la degeneración. La degeneración tiene un gran impacto en las propiedades mecánicas viscoelásticas no lineales del disco intervertebral, que tiene valor de referencia para el mecanismo, tratamiento y prevención de enfermedades clínicas degenerativas.

Is There Any Association between the Severity of Disc Degeneration and Low Back Pain? / Existe alguma associação entre gravidade de degeneração discal e dor lombar?

Abstract Objective To access the possibility that higher degrees of disc degeneration lead to higher levels of pain and dysfunction. Methods Magnetic resonance imaging (MRI) scans of 85 patients with low back pain lasting for more than 12 weeks were evaluated, and the degree of disc degeneration was quantified according to the Pfirrmann grading system. The Pfirrmann degree in each disc space from L1-L2 to L5-S1, the maximum degree of Pfirrmann (Pfirrmannmax) between the lumbar discs, and the sum of Pfirrmann (Pfirrmann-sum) degrees were correlated (through the Spearman test) with the Oswestry Disability Index (ODI) and the Visual Analogical Scale (VAS) for pain. Results In total, 87% of the patients had moderate to severe lumbar disc degeneration measured by Pfirrmann-max, and the most degenerated discs were L4-L5 and L5S1. There was a week to moderate correlation regarding the Pfirrmann-max (r » 0,330; p» 0.002) and the Pfirrmann-sum (r » 0,266; p» 0,037) and the ODI, and the Pfirrmann scores in L1-L2 were correlated with the ODI and the VAS. Conclusion Patients with chronic idiopathic low back pain frequently have moderate to severe lumbar disc degeneration, which has a negative impact on the quality of life of the patients. Low degrees of degeneration in L1-L2 might be related with higher degrees of pain and of functional disability.

Resumo Objetivo Avaliar a possibilidade de maiores graus de degeneração discal levarem a maiores dor e disfunção. Métodos Exames de imagem por ressonância magnética (IRM) de 85 pacientes com lombalgia idiopática por mais de 12 semanas foram avaliados, sendo quantificado o grau de degeneração discal de acordo com a escala de Pfirrmann. O grau de Pfirrmann em cada espaço discal de L1-L2 a L5-S1, o grau máximo de Pfirrmann (Pfirrmann-max) entre os discos lombares, e a soma dos graus de Pfirrmann (Pfirrmann-soma) foram correlacionados (por meio do teste de Spearman) com o Índice de Incapacidade de Oswestry (IIO) e a escala visual analógica (EVA) de dor. Resultados No total, 87% dos pacientes tinha degeneração discal moderada ou acentuada medida pelo Pfirrmann-max, sendo L4-L5 e L5-S1 os discos mais degenerados. Houve uma correlação de fraca a moderada entre o Pfirrmann-max (r » 0,330; p» 0.002) e a Pfirrmann-soma (r » 0,266; p» 0,037) e o IIO, e entre o grau de Pfirrmann em L1-L2 e o IIO e a EVA. Conclusão A degeneração discal lombar moderada ou acentuada é frequente em indivíduos com lombalgia crônica idiopática, e tem um impacto negativo na qualidade de vida dos pacientes. Pequenos graus de degeneração discal em L1-L2 podem determinar maior grau de dor e maior incapacidade funcional.

Improvement in Radicular Pain after Endoscopic Transforaminal Lumbar Discectomy at Discs with Advanced Degenerative Changes / Melhora da dor radicular após discectomia lombar transforaminal endoscópica em discos com alterações degenerativas avançadas

Abstract Objectives To evaluate the correlation between radiologic changes (Pfirrmann and Modic) and radicular pain intensity in patients who underwent transforaminal endoscopic surgery for lumbar disc herniation. Methods Series of cases with 39 patients, 50 intervertebral discs in preoperative evaluation from January 29, 2018 to August 28, 2019 in an endoscopic spine surgery service. Demographic data, surgical indication, operative details and complications were obtained from medical records. The patients were divided into three groups based on the Modic classification (Modic absence, Modic 1 and Modic 2) and into two groups considering the Pfirrmann classification (Pfirrmann IV and Pfirrmann V). Data were processed in IBM SPSS Statistics for Windows, Version 22.0 (IBM Corp., Armonk, NY, USA), with a significance level of p< 0,05. Results There was no difference between genders; age: 50,36 ± 15,05 years old; disease level: L2-L3 1 (2%), L3-L4 2 (4%), L4-L5 9 (18%), L5-S1 8 (16%), L3-L4 + L4-L5 4 (8%), and L4-L5 + L5-S1 26 (52%); location: right foraminal 7 (14%), left foraminal 15 (30%), central 9 (18%) and diffuse 19 (38%); radicular pain: left 25 (50%), right 11 (22%), and bilateral 14 (28%); preoperative visual analogue scale (VAS): 9,5 ± 0,91, postoperative: 2,5 ± 1,79; surgery duration: 100 ± 31,36 minutes; and follow-up: 8,4 ± 6,7 months. Less postoperative sciatica was registered in the Modic 2 versus Modic 1 group (p< 0,05). There was no difference in the postoperative radicular pain between the Pfirrmann groups (IV versus V). Conclusion Although there is no clinical difference between the groups, in advanced stages of disc degeneration, endoscopic transforaminal discectomy proved to be effective in diminishing radicular pain in patients with lumbar disc herniation.

Resumo Objetivos Avaliar a correlação entre as alterações radiológicas (Pfirrmann e Modic) e a intensidade da dor radicular em pacientes submetidos a cirurgia endoscópica transforaminal para hérnia de disco lombar. Métodos Uma sequência de casos com 39 pacientes, 50 discos intervertebrais em avaliação pré-operatória, no período de 29 de janeiro de 2018 a 28 de agosto de 2019, no serviço de cirurgia endoscópica da coluna vertebral. Os dados demográficos, indicação cirúrgica, detalhes operatórios e complicações foram todos obtidos junto aos prontuários clínicos. Os pacientes foram divididos em três grupos, com base na classificação Modic (ausência de Modic, Modic 1 e Modic 2) e em dois grupos, considerando a classificação de Pfirrmann (Pfirrmann IV e Pfirrmann V). Os dados foram processados no software IBM SPSS Statistics for Windows, versão 22.0 (IBM Corp., Armonk, NY, EUA), com nível de significância de p <0,05. Resultados Não houve diferença entre os gêneros; idade: 50,36 ± 15,05 anos; nível da doença: L2-L3 1 (2%), L3-L4 2 (4%), L4-L5 9 (18%), L5-S1 8 (16%), L3-L4 + L4-L5 4 (8%), e L4-L5 + L5-S1 26 (52%); localização: foraminal direito em 7 pacientes (14%), foraminal esquerdo em 15 pacientes (30%), central em 9 pacientes (18%), e difuso em 19 pacientes (38%); dor radicular: esquerda em 25 pacientes (50%), direita em 11 pacientes (22%), e bilateral em 14 pacientes (28%); escala visual analógica (EVA) pré-operatório: 9,5 ± 0,91, pós-operatório: 2,5 ± 1,79; tempo cirúrgico: 100 ± 31,36 minutos; e acompanhamento de 8,4 ± 6,7 meses. Foi registrada menos dor ciática pós-operatória nos grupos Modic 2 versus Modic 1 (p< 0,05). Não houve diferença na dor radicular pós-operatória entre os grupos Pfirrmann (IV versus V). Conclusão Embora não exista diferença clínica entre os grupos, em estágios avançados da degeneração discal, a discectomia transforaminal endoscópica mostrou-se eficaz na redução da dor radicular em pacientes com hérnia de disco lombar.

Minimally invasive swine spine surgery training: technical aspects, benefits, and anatomical limitations

ABSTRACT Objective To describe the technical specificities and feasibility of simulation of minimally invasive spine surgery in live pigs, as well as similarities and differences in comparison to surgery in humans. Methods A total of 22 Large White class swine models, weighing between 60 and 80kg, were submitted to surgical simulations, performed during theoretical-practical courses for training surgical techniques (microsurgical and endoscopic lumbar decompression; percutaneous pedicular instrumentation; lateral access to the thoracic spine, and anterior and retroperitoneal to the lumbar spine, and management of complications) by 86 spine surgeons. For each surgical technique, porcine anatomy (similarities and differences in relation to human anatomy), access route, and dimensions of the instruments and implants used were evaluated. Thus, the authors describe the feasibility of each operative simulation, as well as suggestions to optimize training. Study results are descriptive, with figures and drawings. Results Neural decompression surgeries (microsurgeries and endoscopic) and pedicular instrumentation presented higher similarities to surgery on humans. On the other hand, intradiscal procedures had limitations due to the narrow disc space in swines. We were able to simulate situations of surgical trauma in surgical complication scenarios, such as cerebrospinal fluid fistulas and excessive bleeding, with comparable realism to surgery on humans. Conclusion A porcine model for simulation of minimally invasive spinal surgical techniques had similarities with surgery on humans, and is therefore feasible for surgeon training.

Research progress in mechanism of Chinese herbal compounds and monomers in delaying lumbar intervertebral disc degeneration / 中国中药杂志

Traditional Chinese medicine has unique advantages in the treatment of degenerative bone and joint diseases, and its widely used in clinical practice. In recent years, many scholars have conducted a large number of basic studies on the delay of intervertebral disc degeneration by herbal compound and monomeric components from different perspectives. In order to further elucidate its mechanism of action, this paper summarizes the in vivo and in vitro experimental studies conducted at the level of both herbal compound and single components, respectively, in order to provide references for the basic research on the treatment of lumbar intervertebral disc degeneration by Chinese medicine. A summary shows that commonly used herbal compound prescriptions include both classical prescriptions such as Duhuo Jisheng Decoction, as well as clinical experience prescriptions such as Yiqi Huoxue Recipe. Angelicae Sinensis Radix, Chuanxiong Rhizoma, Rehmanniae Radix Praeparata, Achyranthis Bidentatae Radix, and Eucommiae Cortex were used most frequently. Tonic for deficiency and blood stasis activators were used most frequently. The most utilized monomeric components include icariin, ginsenoside Re, salvianolic acid B and aucubin. The main molecular mechanisms by which herbal compound and monomeric components delay of lumbar intervertebral disc degeneration include improving the intervertebral disc microenvironment, promoting the synthesis of aggregated proteoglycans and type Ⅱ collagen in the intervertebral disc, reducing the degradation of the extracellular matrix, and inhibiting apoptosis in the nucleus pulposus cells, etc. The main signaling pathways involved include Wnt/β-catenin signaling pathway, MAPK-related signaling pathway, mTOR signaling pathway, Fas/FasL signaling pathway, PI3 K/Akt signaling pathway, NF-κB signaling pathway, JAK/STAT signaling pathway, and hedgehog signaling pathway, etc.

Percutaneous endoscopic lumbar discectomy in the treatment of adjacent segment lumbar disc herniation after lumbar fusion / 中国骨伤

OBJECTIVE@#To explore the clinical effect of percutaneous endoscopic lumbar discectomy in the treatment of adjacent segment lumbar disc herniation after lumbar fusion.@*METHODS@#From February 2010 to June 2018, 64 patients with adjacent segment lumbar disc herniation after lumbar fusion were retrospectively analyzed and divided into observation group and control group. In observation group, there were 23 males and 10 females performed with percutaneous endoscopic lumbar discectomy, including 27 cases of single segment fusion and 6 cases of double segment fusion, aged from 55 to 83 years old with an average of (65.7±7.4) years old. In control group, there were 22 males and 9 females performed with traditional open fusion revision, including 25 cases of single-segment fusion and 6 cases of double segment fusion, aged from 51 to 78 years old with an average of(64.8±7.8) years old. The operative time, intraoperative blood loss, fluoroscopy times, postoperative ambulation time and length of postoperative hospital stay were recorded. The clinical efficacy was evaluated by visual analogue scale(VAS) and Oswestry Disability Index(ODI). The complications between two groups were observed.@*RESULTS@#All patients were followed up for at least 2 years. The observation group patients were followed up with an average of (2.4±0.5) years. The control group patients were followed up with an average of(2.6±0.7) years. Compared with control group, operation time, intraoperative blood loss, postoperative ambulation time and length of postoperative hospital stay of the observation group were significantly reduced (P<0.05), and the fluoroscopy times of observation group were significantly increased compared with control group(P<0.05). The VAS of low back and lower limb, and ODI at the latest follow-up between two groups were all significantly improved compared to those of pre-operation (P<0.05). The VAS of low back at each point and ODI at 1, 3 months after operation in observation group was significantly reduced compared with control group(P<0.05), however there was no significant difference in VAS for lower limb between two groups (P>0.05). The difference of complications between two groups was statistically significant (P<0.05).@*CONCLUSION@#Compared with traditional open fusion revision surgery, percutaneous endoscopic lumbar discectomy for the treatment of adjacent segment lumbar disc herniation after lumbar fusion has the advantages of reducing operation time and intra-operative blood loss, shortening ambulation time and the length of postoperative hospital stay, and promoting pain and functional improvement, and decrease incidence of complications. However, long-term clinical efficacy needs further study.

Early efficacy of three dimensional printed anatomical biomimetic cervical artificial disc replacement in the treatment of cervical degenerative diseases / 中华外科杂志

Objective: To investigate the efficacy and safety of a new cervical artificial disc prosthesis in the treatment of cervical degenerative diseases. Methods: The clinical data of 18 patients with single-level cervical degenerative diseases who underwent three dimensional printed anatomical bionic cervical disc replacement at Department of Spinal Surgery,Honghui Hospital,Xi'an Jiaotong University from May 2019 to July 2020 were analyzed retrospectively. There were 7 males and 11 females,aged (45±8) years old(range:28 to 58 years).The surgical segment was located at C3－4 level in 2 cases, C4－5 level in 5 cases, C5－6 level in 9 cases, and C6－7 level in 2 cases.The clinical and radiographic outcomes were recorded and compared at preoperative,postoperative times of one month and twelve months.The clinical assessments contained Japanese orthopedic association (JOA) score,neck disability index (NDI) and visual analogue scale (VAS).Imaging assessments included range of motion (ROM) of cervical spine, prosthesis subsidence and prosthesis anteroposterior migration.Repeated measurement variance analysis was used for comparison between groups,and paired t test was used for pairwise comparison. Results: All patients underwent the operation successfully and were followed up for more than 12 months.Compared with preoperative score,the JOA score,NDI and VAS were significantly improved after surgery (all P<0.01).There was no significant difference in postoperative ROM compared with 1-and 12-month preoperative ROM (t=1.570,P=0.135;t=1.744,P=0.099). The prosthesis subsidence was (0.29±0.13) mm (range: 0.18 to 0.50 mm) at 12-month postoperatively.The migration of prosthesis at 12-months postoperatively were (0.71±0.20) mm (range: 0.44 to 1.08 mm).There was no prosthesis subsidence or migration>2 mm at 12-month postoperatively. Conclusion: Three dimensional printed anatomical biomimetic cervical artificial disc replacement has a good early clinical effect in the treatment of cervical degenerative diseases, good mobility can be obtained while maintaining stability.

The development of artificial cervical disc replacement from the perspective of orthopedic bionic therapy / 中华外科杂志

The modern surgical treatment of cervical degenerative disc disease can be traced back to the advent of anterior cervical decompression and fusion.With the emergence of fusion-related complications,different scholars have promoted the gradual transformation of cervical degenerative disc diseases from "fusion fixation" to "non-fusion reconstruction" through in-depth fusion with materials science,engineering mechanics and other disciplines.The innovation of this treatment concept is consistent with the original intention of "structural remodeling,functional reconstruction,maximum repair and reconstruction of the morphology and function of skeletal muscle system" in orthopedic bionic treatment,which is essentially in line with the "bionic alternative therapy" in orthopedic bionic therapy.This paper focuses on the surgical treatment of cervical degenerative disc diseases,reviews the development history of artificial cervical disc replacement,analyzes the evolution from orthopedic biomimetic therapy,and explores a new direction for the design of artificial cervical disc prostheses and the treatment of cervical degenerative disc diseases in the future.

Value of magnetic resonance combined with dual-source spectral computed tomography in improving the clinical diagnosis and treatment efficiency of lumbar disk herniation

SUMMARY OBJECTIVE: This study aims to investigate the value of magnetic resonance combined with dual-source spectral computed tomography in improving the clinical diagnosis and treatment efficiency of lumbar disk herniation. METHODS: Two hundred patients with lumbar disk herniation were enrolled. Magnetic resonance and dual-source spectral computed tomography were used to perform the diagnosis. The treatment efficiency and effectiveness of different diagnostic methods were determined. Results: Eighty cases of lumbar disk herniation, 40 cases of prolapse, 33 cases of bulge, 27 cases of sequestration, and 20 cases of nodules were diagnosed based on pathologic evaluation. magnetic resonance detected lumbar disk herniation in 172 cases, with a detection rate of 86.00%. Dual-source spectral computed tomography detected 171 cases, with a detection rate of 85.50%. Magnetic resonance combined with dual-source spectral computed tomography detected 195 cases, with a detection rate of 97.50%. There was no significant difference between magnetic resonance and dual-source spectral computed tomography (p>0.05), but compared with the combined detection, there was a significant difference (p<0.05). One hundred and two cases of calcification, 83 cases of spinal cord deformity, 70 cases of intervertebral disk degeneration, 121 cases of intervertebral disk gas, 85 cases of dural sac compression, and 78 cases of nerve root compression were surgically demonstrated. The detection rate of diagnostic signs based on imaging by magnetic resonance or dual-source spectral computed tomography alone was lower than that of combined detection (p<0.05). Conclusion: Magnetic resonance combined with dual-source spectral computed tomography can improve the diagnosis and treatment efficiency and effectiveness of lumbar disk herniation.

Plasma rico en plaqueta en el tratamiento de la enfermedad degenerativa discal / Platelet-rich plasma in the treatment of degenerative disc disease

Introducción: La enfermedad degenerativa discal es una entidad frecuente y uno de los principales motivos de consulta. Genera altas tasas de discapacidad, años útiles perdidos, así como altos costos económicos por asistencia médica y grandes pérdidas monetarias. Su tratamiento es generalmente conservador, aunque en la actualidad se incluyen terapias biológicas novedosas. Objetivo: Describir las principales propiedades biológicas que hacen del plasma rico en plaquetas una terapéutica efectiva para la enfermedad degenerativa discal. Métodos: Se realizó una revisión no sistemática de la bibliografía basada en artículos que se publicaron en bases de datos indexadas en Infomed como Hinari, Ebsco, Scielo, Pubmed, Cubmed, Cocrhane, Scopus, LILACS; en idioma español, inglés y portugués, durante los últimos diez años. Desarrollo: Se expusieron características clínico epidemiológicas de la enfermedad degenerativa discal, así como las propiedades biológicas que le permiten al plasma rico en plaqueta tener una función activa en la regeneración del disco intervertebral o el retraso de la cascada de degradación de este. Se resaltan los principales estudios de acuerdo a la vía de administración del plasma rico en plaquetas y sus resultados. Conclusiones: De acuerdo con lo publicado por los autores, el plasma rico en plaquetas es una alternativa efectiva en el tratamiento de la enfermedad degenerativa discal por la producción de factores derivados de las plaquetas, que intervienen en la degeneración del disco intervertebral, siendo la vía intradiscal la que más se emplea(AU)

Introduction: Degenerative disc disease is a frequent condition and one of the main reasons to attend the consultation. It generates high rates of disability, useful years lost, as well as high economic costs for medical assistance and large monetary losses. Its treatment is generally conservative, although novel biological therapies are currently included. Objective: To describe the main biological properties that make platelet-rich plasma an effective therapy against degenerative disc disease. Methods: A nonsystematic review of the bibliography was carried out based on articles published, during the last ten years, in databases indexed in Infomed, such as Hinari, Ebsco, Scielo, Pubmed, Cubmed, Cocrhane, Scopus, and LILACS, in Spanish, English and Portuguese. Development: Clinical-epidemiological characteristics of degenerative disc disease were presented, as well as the biological properties that allow platelet-rich plasma to have an active function in the regeneration of the intervertebral disc or the delay of its degradation cascade. The main studies are highlighted, according to the route of administration of platelet-rich plasma and their results. Conclusions: According to what has been published by authors, platelet-rich plasma is an effective alternative in the treatment of degenerative disc disease, due to the production of factors derived from platelets, which intervene in the degeneration of the intervertebral disc, being the intradiscal pathway the most used(AU)

Finite Element Analysis of a Controlled Dynamization Device for External Circular Fixation / Análise de elementos finitos de um dispositivo de dinamização controlada para fixação circular externa

Abstract Objective To virtually prototype a device for external circular fixation of long bone fractures with controlled dynamization made of two different materials and predict their mechanical behavior by using the finite element analysis (FEA) method. Method A software was used for 3D modeling two metal parts closely attached by a sliding dovetail joint and a high-density silicone damper. Distinctive FEAs were simulated by considering two different materials (stainless steel or titanium), modes (locked or dynamized) and loading conditions (static/point or dynamic/0.5 sec) with uniform 150 kg axial load on top of the device. Results The finite elements (FEs) model presented 81,872 nodes and 45,922 elements. Considering stainless steel, the maximum stress peak (140.98 MPa) was reached with the device locked under static loading, while the greatest displacement (2.415 × 10−3 mm) was observed with the device locked and under dynamic loading. Regarding titanium, the device presented the maximum stress peak (141.45 MPa) under static loading and with the device locked, while the greatest displacement (3.975 × 10−3 mm) was found with the device locked and under dynamic loading. Conclusion The prototyped device played the role of stress support with acceptable deformation in both locked and dynamized modes and may be fabricated with both stainless steel and titanium.

Resumo Objetivo Construir um protótipo virtual de um dispositivo de fixação circular externa para fraturas em ossos longos com dinamização controlada a partir de dois materiais diferentes e prever seu comportamento mecânico por meio da análise de elementos finitos AEF). Método Modelos tridimensionais compostos de duas peças metálicas unidas por uma junta deslizante em rabo de andorinha e um amortecedor de silicone de alta densidade foram criados em um software. Análises de elementos finitos distintas foram simuladas considerando dois materiais (aço inoxidável ou titânio), modos (bloqueado ou dinamizado) e condições de carregamento (estático/pontual ou dinâmico/0,5 segundo) diferentes com carga axial uniforme de 150 kg na porção superior do dispositivo. Resultados O modelo de elementos finitos (EFs) apresentou 81.872 nós e 45.922 elementos. Com aço inoxidável, o pico de tensão máxima (140,98 MPa) foi alcançado com o dispositivo bloqueado e sob carga estática, enquanto o maior deslocamento (2.415 × 10−3 mm) foi obtido com o dispositivo bloqueado e sob carga dinâmica. Com titânio, o pico de tensão máxima (141,45 MPa) ocorreu com o dispositivo bloqueado e sob carga estática, enquanto o maior deslocamento (3.975 × 10−3 mm) foi observado com o dispositivo bloqueado e sob carga dinâmica. Conclusão O protótipo do dispositivo desempenhou o papel de suporte de tensão com deformação aceitável nos dois modos, bloqueado ou dinamizado, e pode ser fabricado com aço inoxidável ou titânio.

Adult Degenerative Scoliosis / Escoliose degenerativa do adulto

Abstract Populational aging increases the incidence of musculoskeletal degenerative processes, such as adult scoliosis (AS). Adult scoliosis is defined as a spinal deformity in the coronal plane with a Cobb angle > 10º. Adult scoliosis may be iatrogenic or result from a degenerative process (scoliosis de novo) or a pre-existing scoliosis. Adult scoliosis is a potentially limiting condition that affects a heterogeneous group of patients. Clinical treatment proved to be ineffective and surgery is often indicated. The present paper reviews AS pathophysiology, clinical presentation and diagnosis, in addition to surgical indications and the main techniques currently used.

Resumo O envelhecimento da população aumenta a incidência dos processos degenerativos osteomusculares, como a escoliose do adulto (EA). A EA é definida como uma deformidade da coluna no plano coronal com ângulo de Cobb > 10º e pode ocorrer devido a um processo degenerativo (escoliose de novo), evolução de uma escoliose pré-existente ou de forma iatrogênica. A EA é uma doença potencialmente limitante que acomete um grupo heterogêneo de pacientes. O tratamento clínico se mostrou pouco efetivo e a indicação cirúrgica é frequente. No presente artigo, é apresentada uma revisão sobre a fisiopatologia, a manifestação clínica e o diagnóstico da EA. Também são apresentadas as indicações cirúrgicas e as principais técnicas utilizadas atualmente.

Pharmacological inhibition of mTORC1 activity protects against inflammation-induced apoptosis of nucleus pulposus cells

Lumbar disc herniation is a common disease characterized by the degeneration of intervertebral discs (IVDs), accompanied by imbalance of metabolic and inflammatory homeostasis. Current studies establish that IVD degeneration is induced by increased apoptosis of nucleus pulposus (NP) cells. However, the underlying mechanisms of NP cell survival/apoptosis are not well elucidated. Here, we reveal a novel mechanism by which mTORC1 signaling controls NP cell survival through regulating metabolic homeostasis. We demonstrated that hyperactivated mTORC1 activity induced by inflammatory cytokines engenders the apoptosis of NP cells, whereas pharmacological inhibition of mTORC1 activity promotes NP cell survival. Using an integrative approach spanning metabolomics and biochemical approaches, we showed that mTORC1 activation enhanced glucose metabolism and lactic acid production, and therefore caused NP cell apoptosis. Our study identified mTORC1 in NP cells as a novel target for IVD degeneration, and provided potential strategies for clinical intervention of lumbar disc herniation.

Clinical study on improving the strength and activity of lumbar spine with Qiang Jin exercises / 中国骨伤

OBJECTIVE@#To observe the effect of Qiang Jin exercises on the muscle strength and activity of lumbar spine in patients with lumbar disc herniation.@*METHODS@#From March 2016 to September 2017, at the Department of Orthopaedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, a total of 110 subjects were enrolled, and 98 eligible subjects were screened. The subjects were randomized by stratified randomization and divided into experimental group and control group, 49 cases in each group, 25 males and 24 females in the experimental group, 25 males and 24 females in the control group. The experimental group exercised with Qiang Jin exercises, one time each morning and evening, each time10 sets were made;the control group used classic rehabilitation training, training twice a week, and three months was a course of treatment. After 12 weeks of training, the muscle strength and activity of the lumbar spine were evaluated and compared with the muscle strength and activity of the lumbar spine before training.@*RESULTS@#The experimental group and the control group had different muscle strength and activity of the lumbar spine before and after treatment (@*CONCLUSION@#Qiang Jin exercises can effectively improve the muscle strength and activity of the lumbar spine and improve the daily living ability of patients.

Research progress on three-dimensional printed interbody fusion cage / 生物医学工程学杂志

Spinal fusion is a standard operation for treating moderate and severe intervertebral disc diseases. In recent years, the proportion of three-dimensional printing interbody fusion cage in spinal fusion surgery has gradually increased. In this paper, the research progress of molding technology and materials used in three-dimensional printing interbody fusion cage at present is summarized. Then, according to structure layout, three-dimensional printing interbody fusion cages are classified into five types: solid-porous-solid (SPS) type, solid-porous-frame (SPF) type, frame-porous-frame (FPF) type, whole porous cage (WPC) type and others. The optimization process of three-dimensional printing interbody fusion cage and the advantages and disadvantages of each type are analyzed and summarized in depth. The clinical application of various types of 3D printed interbody fusion cage was introduced and summarized later. Lastly, combined with the latest research progress and achievements, the future research direction of three-dimensional printing interbody fusion cage in molding technology, application materials and coating materials is prospected in order to provide some reference for scholars engaged in interbody fusion cage research and application.

Channel-assisted fixation and interbody fusion in treating recurrent lumbar disc herniation by muscle-splitting approach / 中国骨伤

OBJECTIVE@#To explore the clinical value and safety of unilateral pedicle screw fixation combined with contralateral translaminar facet screw fixation and interbody fusion by muscle-splitting approach treatment of recurrent lumbar disc herniation.@*METHODS@#The clinical data of 51 patients with recurrent lumbar disc herniation treated from June 2012 to December 2017 were retrospectively analyzed. There were 32 males and 19 females, aged 34 to 64 years with an average of (51.11± 7.28) years. Lesions invoved L@*RESULTS@#There was no statistical difference in operation time between two groups (@*CONCLUSION@#Muscle-splitting approach is feasible for thetreatment of recurrent lumbar disc herniation with pedicle screw fixation combined with contralateral translaminar facet screw fixation and interbody fusion. Compared with the median incision approach, the muscle-splitting approach has the advantages of small incision, less trauma, less bleeding, rapid recovery. Also it can protect multifidus and do not increase the incidence of serious complications. Thus, it can be used as a choice for fixation and fusion of recurrent lumbar disc herniation.

Clinical application of self-made minimally invasive hood-assisted transforaminal lumbar interbody fusion via modified bilateral Wiltse approach in the treatment of lumbar degenerative diseases / 中国骨伤

OBJECTIVE@#To explore the advantages of self made minimally invasive hook assisted transforaminal lumbar interbody fusion (TLIF) via modified bilateral Wiltse approach in the treatment of lumbar degenerative diseases.@*METHODS@#The clinical data of 140 patients underwent lumbar spine fusion surgery from October 2016 to October 2017 were retrospectively analyzed. Among them, 72 cases were treated by self-made minimally invasive hook-assisted TLIF via modified bilateral Wiltse approach (group A), there were 37 males and 35 females, aged (48±16) years old;68 cases were treated by TLIF via traditional posterior median approach (group B ), there were 38 males and 30 females, aged (45±15) years old. The surgical incision size, operation time, intraoperative blood loss volume, postoperative drainage volume, postoperative wound healing, and intervertebral fusion rate at the final follow-up were recorded between two groups. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) were used to assess the clinical efficacy.@*RESULTS@#All the patients were followed up for 3 to 13 (8±5) months. The wound in group A healed well after operation, and 1 case in group B occurred wound necrosis after operation, and healed after debridement and suture. There were no significant differences in operation time and postoperative fusion rate between two surgical methods (@*CONCLUSION@#The self made minimally invasive hook assistedTLIF via modified bilateral Wiltse approach has the characteristics of minimally invasive, less intraoperative blood loss, less postoperative drainage, fewer complications, and more stable fusion in the treatment of lumbar degenerative desease.