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Rui Zhu, Wen-Xin Niu, Zhi-Peng Wang, Xiao-Long Pei, Bin He, Zhi-Li Zeng, Li-Ming Cheng
The normal physiological loads from muscles experienced by the spine are largely unknown due to a lack of data. The aim of this study is to investigate the effects of varying muscle directions on the outcomes predicted from finite element models of human lumbar spine. A nonlinear finite element model of L3-L5 was employed. The force of the erector spinae muscle, the force of the rectus abdominis muscle, follower loads, and upper body weight were applied. The model was fixed in a neural standing position and the direction of the force of the erector spinae muscle and rectus abdominis muscle was varied in three directions...
2018: BioMed Research International
Jigang Lou, Yuanchao Li, Beiyu Wang, Yang Meng, Quan Gong, Hao Liu
BACKGROUND: Most of the current available cervical disc prostheses present a flat surface instead of an arcuate surface which is most similar to the morphology of cervical endplate. Therefore, we designed a novel prosthesis (Pretic-I, Trauson) based on the physiological curvature of the cervical endplate. Biomechanical evaluation of cervical disc replacement (CDR) with this novel prosthesis was performed and compared with the Prestige LP prosthesis. METHODS: Three motion segments of 18 cadaveric cervical specimens (C2-C7) were evaluated with a 75 N follower load...
February 27, 2018: Journal of Orthopaedic Surgery and Research
Xin Zhao, Lin Du, Youzhuan Xie, Jie Zhao
OBJECTIVE: Here we used a finite element (FE) analysis to investigate the biomechanical changes caused by transforaminal lumbar interbody fusion (TLIF) at the L4-L5 level by lumbar lordosis (LL) degree. METHODS: A lumbar FE model (L1-S5) was constructed based on computed tomography scans of a 30-year-old healthy male volunteer (pelvic incidence = 50°, LL = 52°). We investigated the influence of LL on the biomechanical behavior of the lumbar spine after TLIF in L4-L5 fusion models with 57°, 52°, 47°, and 40° LL...
February 21, 2018: World Neurosurgery
Wei Yuan, Haiping Zhang, Xiaoshu Zhou, Weidong Wu, Yue Zhu
OBJECTIVE: Artificial cervical disc replacement is expected to maintain normal cervical biomechanics. The effect of Prestige LP prosthesis height on cervical biomechanics has not been thoroughly studied yet. This finite element (FE) study of the cervical biomechanics aims to predict how the parameters like range of motion (ROM), adjacent intradiscal pressure, facet joint force and bone-implant interface stress are affected by different Prestige LP prosthesis heights. METHODS: The FE model of intact cervical spine (C3-C7) was obtained from our previous study, and the model was altered to implant Prestige LP prostheses at the C5-C6 level...
February 17, 2018: World Neurosurgery
Joseph L Laratta, Jamal N Shillingford, Comron Saifi, K Daniel Riew
Study Design: Systematic review. Objectives: Degenerative disc disease and spondylosis resulting in radiculopathy and retrodiscal myelopathy are among the most frequently encountered cervical spinal disorders. Traditionally, anterior cervical discectomy and fusion (ACDF) has successfully achieved neural decompression and restored intradiscal height in these conditions. Unfortunately, nonunion and iatrogenic adjacent segment pathology associated with fusion procedures in the cervical spine has led to an interest in motion-preserving procedures...
February 2018: Global Spine Journal
Mohammad Nikkhoo, Jaw-Lin Wang, Mohamad Parnianpour, Marwan El-Rich, Kinda Khalaf
Understanding the effect of impact loading on the mechanical response of the intervertebral disc (IVD) is valuable for investigating injury mechanisms and devising effective therapeutic modalities. This study used 24 porcine thoracic motion segments to characterize the mechanical response of intact (N = 8), degenerated (Trypsin-denatured, N = 8), and repaired (Genepin-treated, N = 8) IVDs subject to impact loading. A meta-model analysis of poroelastic finite element simulations was used in combination with ex-vivo creep and impact tests to extract the material properties...
January 31, 2018: Journal of Biomechanics
Shady Elmasry, Shihab Asfour, Francesco Travascio
Percutaneous pedicle screw fixation (PPSF) is a minimally invasive surgery (MIS) employed in the treatment of thoracolumbar burst fractures (TBF). However, hardware failure and loss of angular correction are common limitations caused by the poor support of the anterior column of the spine. Balloon Kyphoplasty (KP) is another MIS successfully used in the treatment of compression fractures by augmenting the injured vertebral body with cement. To overcome its limitations as a stand-alone procedure, it was suggested to augment PPSF with KP when treating TBF...
February 1, 2018: Journal of Biomechanical Engineering
Kai-Uwe Lewandrowski, Mathias Ostergren, Paulo Sergio Teixera de Carvalho
Advanced videoendoscopic equipment (such as motorized drills, chisels, and rongeurs) facilitates the use of modern decompression tools through the inner working channel of the spinal endoscope using the transforaminal approach. Postoperative dysesthetic leg pain, however, is common because of irritation of the dorsal root ganglion. This article presents a novel surgical technique employing an expandable balloon placed into the hollow intervertebral space in patients without any functional disc tissue to distract the stenotic motion segment...
January 1, 2018: Surgical Innovation
Xiexing Wu, Yu Liu, Xiaobin Guo, Wei Zhou, Liangliang Wang, Jiawei Shi, Yunxia Tao, Mo Zhu, Dechun Geng, Huilin Yang, Haiqing Mao
Intervertebral disc degeneration (IVDD) is one of the key predisposing factors for low back pain. Although the exact mechanism remains unclear, inflammatory response and nucleus pulposus (NP) apoptosis are known to play important roles in this process. Prolactin protects against inflammation-associated chondrocyte apoptosis in arthritis. Based on prior studies, we hypothesized that prolactin might have therapeutic effects on IVDD by inhibiting the apoptosis of degenerative human disc NP cells. An experimental model of IVDD was established in 3-month-old Sprague-Dawley rats by submitting them to percutaneous disc puncture with a 20-gauge needle on levels 7-8 and 8-9 of the coccygeal vertebrae...
January 24, 2018: Cell Death & Disease
Havva Sayhan, Serbülent Gökhan Beyaz, Ali Metin Ülgen, Mehmet Fatih Yuce, Yakup Tomak
BACKGROUND: Radiopaque gelified ethanol (RGE; DiscoGel, Gelscom SAS, France) is used as a chemonucleolysis substance in treating intradiscal herniation, showing good results without complications. It has also been used in cervical disc herniations (CDHs), demonstrating the potential efficacy of this substance. OBJECTIVE: The aim of the study is to investigate the long-term effectiveness and safety of DiscoGel in patients with CDH and chronic neck pain. STUDY DESIGN: This is a cross-sectional, single-center study...
January 2018: Pain Physician
Abdelraheem Elawamy, Emad Zarief Kamel, Manal Hassanien, Ola M Wahba, Shereen Ezzat Amin
BACKGROUND: Low back pain (LBP) is mostly induced by disc herniation (DH) or degeneration and has a burden upon social activity and economical aspects of life. An abundance of medical and surgical interventions have evolved to resolve this problem, but one of the newly introduced techniques, which is the minimally invasive, low cost ozone-oxygen mixture (O₃-O₂) intradiscal injection, offers a rapid onset amelioration of symptoms with a sustained duration of pain relief. OBJECTIVE: We aim to evaluate the quality of pain alleviation using 2 different doses of intradiscal injections of O₃-O₂ mixture...
January 2018: Pain Physician
Xiaofei Cheng, Liang Zhang, Kai Zhang, Guoying Zhang, Ying Hu, Xiaojiang Sun, Changqing Zhao, Hua Li, Yan Michael Li, Jie Zhao
OBJECTIVES: Circular RNAs (circRNAs) have been proven to function as competing endogenous RNAs to interact with microRNAs (miRNAs) and influence the expression of miRNA target mRNAs. In this study, we investigated whether circRNAs could act as competing endogenous RNAs to regulate the pathological process of intervertebral disc degeneration (IVDD). METHODS: The role and mechanism of a circRNA, circVMA21, in IVDD were explored in nucleus pulposus (NP) cells and degenerative NP tissues from patients and rat models...
January 17, 2018: Annals of the Rheumatic Diseases
Gernot Lang, Yishan Liu, Janna Geries, Zhiyu Zhou, David Kubosch, Norbert Südkamp, R Geoff Richards, Mauro Alini, Sibylle Grad, Zhen Li
OBJECTIVE: The aim of this study was to compare the effect of different disease initiators of degenerative disc disease (DDD) within an intervertebral disc (IVD) organ culture system, and to understand the interplay between inflammation and degeneration in the early stage of DDD. DESIGN: Bovine caudal IVDs were cultured within a bioreactor for up to 11 days. Control group was cultured under physiological loading (0.02-0.2 MPa; 0.2 Hz; 2h/day) and high glucose (4...
January 10, 2018: Journal of Tissue Engineering and Regenerative Medicine
Jason A Actis, Jasmin D Honegger, Deanna H Gates, Anthony J Petrella, Luis A Nolasco, Anne K Silverman
Low back mechanics are important to quantify to study injury, pain and disability. As in vivo forces are difficult to measure directly, modeling approaches are commonly used to estimate these forces. Validation of model estimates is critical to gain confidence in modeling results across populations of interest, such as people with lower-limb amputation. Motion capture, ground reaction force and electromyographic data were collected from ten participants without an amputation (five male/five female) and five participants with a unilateral transtibial amputation (four male/one female) during trunk-pelvis range of motion trials in flexion/extension, lateral bending and axial rotation...
December 13, 2017: Journal of Biomechanics
Pooria Hosseini, Gregory M Mundis, Robert K Eastlack, Ramin Bagheri, Enrique Vargas, Stacie Tran, Behrooz A Akbarnia
OBJECTIVE Sagittal malalignment decreases patients' quality of life and may require surgical correction to achieve realignment goals. High-risk posterior-based osteotomy techniques are the current standard treatment for addressing sagittal malalignment. More recently, anterior lumbar interbody fusion, anterior column realignment (ALIF ACR) has been introduced as an alternative for correction of sagittal deformity. The objective of this paper was to report clinical and radiographic results for patients treated using the ALIF-ACR technique...
December 2017: Neurosurgical Focus
Yolanda Más, Luis Gracia, Elena Ibarz, Sergio Gabarre, Diego Peña, Antonio Herrera
Arthrodesis is a recommended treatment in advanced stages of degenerative disc disease. Despite dynamic fixations were designed to prevent abnormal motions with better physiological load transmission, improving lumbar pain and reducing stress on adjacent segments, contradictory results have been obtained. This study was designed to compare differences in the biomechanical behaviour between the healthy lumbar spine and the spine with DYNESYS and DIAM fixation, respectively, at L4-L5 level. Behaviour under flexion, extension, lateral bending and axial rotation are compared using healthy lumbar spine as reference...
2017: PloS One
Vahid Abdollah, Eric C Parent, Michele C Battié
BACKGROUND: McKenzie prone press-up exercises have been hypothesised to reduce intradiscal pressure, allowing fluid to be reabsorbed into the disc, which could improve the internal stability and local chemical milieu of the disc, potentially reducing symptoms. OBJECTIVE: To investigate the immediate effects of prone press-up exercises on lumbar disc fluid content and movement. DESIGN: Quantification of MRI changes before and after a single exercise session...
February 2018: Musculoskeletal Science & Practice
Hongwei Wang, Yiwen Zhao, Zhongjun Mo, Jianda Han, Yu Chen, Hailong Yu, Qi Wang, Jun Liu, Changqing Li, Yue Zhou, Liangbi Xiang
OBJECTIVES: No studies have compared monoaxial and polyaxial pedicle screws with regard to the von Mises stress of the instrumentation, intradiscal pressures of the adjacent segment and adjacent segment degeneration. METHODS: Short-segment monoaxial/polyaxial pedicle screw fixation techniques were compared using finite element methods, and the redistributed T11-L1 segment range of motion, largest maximal von Mises stress of the instrumentation, and intradiscal pressures of the adjacent segment under displacement loading were evaluated...
October 2017: Clinics
Tao Liu, Kinda Khalaf, Sadegh Naserkhaki, Marwan El-Rich
Understanding load-sharing in the spine during in-vivo conditions is critical for better spinal implant design and testing. Previous studies of load-sharing that considered actual spinal geometry applied compressive follower load, with or without moment, to simulate muscle forces. Other studies used musculoskeletal models, which include muscle forces, but model the discs by simple beams or spherical joints and ignore the articular facet joints. This study investigated load-sharing in neutral standing and flexed postures using a detailed Finite Element (FE) model of the ligamentous lumbosacral spine, where muscle forces, gravity loads and intra-abdominal pressure, as predicted by a musculoskeletal model of the upper body, are input into the FE model...
November 6, 2017: Journal of Biomechanics
Hemant Kumar, Doo-Hoe Ha, Eun-Jong Lee, Jun Hee Park, Jeong Hyun Shim, Tae-Keun Ahn, Kyoung-Tae Kim, Alexander E Ropper, Seil Sohn, Chung-Hun Kim, Devang Kashyap Thakor, Soo-Hong Lee, In-Bo Han
BACKGROUND: Adipose tissue-derived mesenchymal stem cells (AT-MSCs) offer potential as a therapeutic option for chronic discogenic low back pain (LBP) because of their immunomodulatory functions and capacity for cartilage differentiation. The goal of this study was to assess the safety and tolerability of a single intradiscal implantation of combined AT-MSCs and hyaluronic acid (HA) derivative in patients with chronic discogenic LBP. METHODS: We performed a single-arm phase I clinical trial with a 12-month follow-up and enrolled 10 eligible chronic LBP patients...
November 15, 2017: Stem Cell Research & Therapy
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