scholarly journals Thermal-Induced Osteonecrosis of Adjacent Vertebra after Intradiscal Electrothermal Therapy

2017 ◽  
Vol 60 (1) ◽  
pp. 114-117
Author(s):  
Soonjoon Kim ◽  
Sun-Ho Lee ◽  
Eun-Sang Kim ◽  
Whan Eoh
Keyword(s):  
Adjacent Vertebra

A Model of the Human Spine: Forward and Inverse Kinematics

1992 ◽  
Author(s):  
Sunil Kumar Agrawal ◽  
Siyan Li ◽  
Glen Desmier
Keyword(s):  
Range Of Motion ◽  
Inverse Kinematics ◽  
Degrees Of Freedom ◽  
Kinematic Model ◽  
Joint Angles ◽  
Human Spine ◽  
Forward And Inverse Kinematics ◽  
Position And Orientation ◽  
Three Degrees Of Freedom ◽  
Adjacent Vertebra

Abstract The human spine is a sophisticated mechanism consisting of 24 vertebrae which are arranged in a series-chain between the pelvis and the skull. By careful articulation of these vertebrae, a human being achieves fine motion of the skull. The spine can be modeled as a series-chain with 24 rigid links, the vertebrae, where each vertebra has three degrees-of-freedom relative to an adjacent vertebra. From the studies in the literature, the vertebral geometry and the range of motion between adjacent vertebrae are well-known. The objectives of this paper are to present a kinematic model of the spine using the available data in the literature and an algorithm to compute the inter vertebral joint angles given the position and orientation of the skull. This algorithm is based on the observation that the backbone can be described analytically by a space curve which is used to find the joint solutions..

scholarly journals Effects of vertebroplasty on endplate subsidence in elderly female spines

2015 ◽  
Vol 22 (3) ◽  
pp. 273-282 ◽  
Author(s):  
Srinidhi Nagaraja ◽  
Hassan K. Awada ◽  
Maureen L. Dreher ◽  
John T. Bouck ◽  
Shikha Gupta
Keyword(s):  
Bone Cement ◽  
Trabecular Bone ◽  
Volume Fraction ◽  
Micro Ct ◽  
Control Groups ◽  
Bone Volume Fraction ◽  
Elderly Female ◽  
Maximum Subsidence ◽  
And Control ◽  
Adjacent Vertebra

OBJECT The aim in this study was to quantify the effects of vertebroplasty on endplate subsidence in treated and adjacent vertebrae and their relationship to endplate thickness and underlying trabecular bone in elderly female spines. METHODS Vertebral compression fractures were created in female cadaveric (age range 51–88 years) thoracolumbar spine segments. Specimens were placed into either the control or vertebroplasty group (n = 9/group) such that bone mineral density, trabecular microarchitecture, and age were statistically similar between groups. For the vertebroplasty group, polymethylmethacrylate bone cement was injected into the fractured vertebral body under fluoroscopy. Cyclic compression (685–1370 N sinusoid) was performed on all spine segments for 115,000 cycles. Micro-CT scans were obtained before and after cyclic loading to quantify endplate subsidence. Maximum subsidence was compared between groups in the caudal endplate of the superior adjacent vertebra (SVcau); cranial (TVcra) and caudal (TVcau) endplates of the treated vertebra; and the cranial endplate of the inferior adjacent vertebra (IVcra). In addition, micro-CT images were used to quantify average endplate thickness and trabecular bone volume fraction. These parameters were then correlated with maximum endplate subsidence for each endplate. RESULTS The maximum subsidence in SVcau endplate for the vertebroplasty group (0.34 ± 0.58 mm) was significantly (p < 0.05) greater than for the control group (−0.13 ± 0.27 mm). Maximum subsidence in the TVcra, TVcau, and IVcra endplates were greater in the vertebroplasty group, but these differences were not significant (p > 0.16). Increased subsidence in the vertebroplasty group manifested locally in the anterior region of the SVcau endplate and in the posterior region of the TVcra and TVcau endplates (p < 0.10). Increased subsidence was observed in thinner endplates with lower trabecular bone volume fraction for both vertebroplasty and control groups (R2 correlation up to 62%). In the SVcau endplate specifically, these 2 covariates aided in understanding subsidence differences between vertebroplasty and control groups. CONCLUSIONS Bone cement injected during vertebroplasty alters local biomechanics in elderly female spines, resulting in increased endplate disruption in treated and superior adjacent vertebrae. More specifically, bone cement increases subsidence in the posterior regions of the treated endplates and the anterior region of the superior caudal endplate. This increased subsidence may be the initial mechanism leading to subsequent compression fractures after vertebroplasty, particularly in vertebrae superior to the treated level.

Characterization of In Vivo Lumbar Range of Motion During Flexion in Healthy Subjects

2013 ◽  
Author(s):  
Amy A. Claeson ◽  
David J. Nuckley ◽  
Victor H. Barocas
Keyword(s):  
Facet Joint ◽  
Spinous Process ◽  
Posterior Spine ◽  
Lumbar Range Of Motion ◽  
Lumbar Facet ◽  
Flexion And Extension ◽  
Adjacent Vertebra ◽  
Spinal Flexion

The lumbar facet joint (FJ) is a unique structure located on the posterior spine. The joint is composed of two articular facets from adjacent vertebrae, which are connected by a flexible and strong facet capsular ligament (FCL) (Figure 1). Two FJs (one on each side of the spinous process) are located at every spine level and along with the IVD, create a motion segment. During spinal flexion and extension, the FCL undergoes a complex motion, with extension and shear dominating the deformation (Figure 2). The collagenous FCL guides and restricts the relative motion of adjacent vertebra in flexion.

scholarly journals Prophylactic adjacent-segment vertebroplasty following kyphoplasty for a single osteoporotic vertebral fracture and the risk of adjacent fractures: a retrospective study and clinical experience

2016 ◽  
Vol 25 (4) ◽  
pp. 528-534 ◽  
Author(s):  
Martin C. Eichler ◽  
Christian Spross ◽  
Alexander Ewers ◽  
Ryan Mayer ◽  
Fabrice A. Külling
Keyword(s):  
Retrospective Study ◽  
Osteoporotic Fractures ◽  
Adjacent Segment ◽  
Single Segment ◽  
Vertebral Body Fractures ◽  
Study Population ◽  
The Mean ◽  
Adjacent Fractures ◽  
Adjacent Vertebra

OBJECTIVE This study investigated the benefit of prophylactic vertebroplasty of the adjacent vertebrae in single-segment osteoporotic vertebral body fractures treated with kyphoplasty. METHODS All patients treated with kyphoplasty for osteoporotic single-segment fractures between January 2007 and August 2012 were included in this retrospective study. The patients received either kyphoplasty alone (kyphoplasty group) or kyphoplasty with additional vertebroplasty of the adjacent segment (vertebroplasty group). The segmental kyphosis with the rate of adjacent-segment fractures (ASFs) and remote fractures were studied on plain lateral radiographs preoperatively, postoperatively, at 3 months, and at final follow-up. RESULTS Thirty-seven (82%) of a possible 45 patients were included for the analysis, with a mean follow-up of 16 months (range 3–54 months). The study population included 31 women, and the mean age of the total patient population was 72 years old (range 53–86 years). In 21 patients (57%), the fracture was in the thoracolumbar junction. Eighteen patients were treated with additional vertebroplasty and 19 with kyphoplasty only. The segmental kyphosis increased in both groups at final follow-up. A fracture through the primary treated vertebra (kyphoplasty) was found in 4 (22%) of the vertebroplasty group and in 3 (16%) of the kyphoplasty group (p = 0.6). An ASF was found in 50% (n = 9) of the vertebroplasty group and in 16% (n = 3) of the kyphoplasty group (p = 0.03). Remote fractures occurred in 1 patient in each group (p = 1.0). CONCLUSIONS Prophylactic vertebroplasty of the adjacent vertebra in patients with single-segment osteoporotic fractures as performed in this study did not decrease the rate of adjacent fractures. Based on these retrospective data, the possible benefits of prophylactic vertebroplasty do not compensate for the possible risks of an additional cement augmentation.

scholarly journals VLIYaNIE ISSLEDOVANIYa MINERAL'NOY PLOTNOSTI KOSTI (MPK) V STANDARTNYKh LOKALIZATsIYaKh I DOPOLNITEL'NYKh IZMERENIY MPK NA USTANOVLENIE DIAGNOZA OSTEOPOROZA

2005 ◽  
Vol 8 (2) ◽  
pp. 21-24
Author(s):  
M P RUBIN ◽  
R E ChEChURIN
Keyword(s):  
Bone Mineral Density ◽  
Bone Mineral ◽  
Mineral Density ◽  
X Ray ◽  
Diagnostic Categories ◽  
Fracture Threshold ◽  
Femur Neck ◽  
Two Sides ◽  
Adjacent Vertebra

The aim of the study was to improve the quality of densitometric evaluations of bone mineral density disorders. Dual-energy x-ray absorbtiometry data collected in 874 females were analyzed. All patients had got bone mineral density examination of the lumbar spine, proximal femur at the both sides; some of the patients also had been measured at the distal radius. We hypothesize that the judgment of diagnostic categories (osteoporosis stages) should include consideration of bone mineral density data both for L2-L4 and for any of two adjacent vertebra, as well as variations of the femur neck data between the two sides. Ultradistal forearm bone densitometry was carried out for osteopenic patients who had had a Colles'fracture -to estimate fracture risk for the opposite radius. The osteoporotic fracture threshold for such cases may be at T-Score of -.1.

scholarly journals Comparison of the clinical outcomes of percutaneous vertebroplasty vs. kyphoplasty for the treatment of osteoporotic Kümmell’s disease:a prospective cohort study

2020 ◽  
Author(s):  
Jian-Zhong Chang ◽  
Ming-Jian Bei ◽  
Dong-Ping Shu ◽  
Cheng-Jun Sun ◽  
Ji-Bin Chen ◽  
...  
Keyword(s):  
Blood Loss ◽  
Bone Cement ◽  
Percutaneous Vertebroplasty ◽  
Operation Time ◽  
Cement Leakage ◽  
Significant Difference ◽  
Kummell’S Disease ◽  
Adjacent Vertebra ◽  
Kümmell’S Disease ◽  
Time Point

Abstract Background Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are widely used in the treatment of Kümmell's disease. The purpose of this article is to investigate the clinical efficacy of PVP and PKP for Kümmell's disease. Methods The clinical data that 56 cases of OVCF treated with either PVP (28 cases) or PKP (28 cases) and met the selection criteria from December 2015 to December 2017 were prospectively analyzed. Gender, age, course of disease, injury segment, BMD, VAS, ODI, imaging measurement indexes before surgery between the two groups showed no significant difference (all P>0.05). The bone cement leakage rate, bone cement injection amount, operation time, VAS, ODI, the rate of vertebral compression, correction rate of kyphosis and refracture rate of adjacent vertebra in 2 years were compared between the two groups to calculate clinical efficacy. Results The two groups were followed up for 24-48 months. There was no significant difference in the follow-up time, amount of bone cement injected, incidence of bone cement leakage and refracture rate of adjacent vertebra between the two groups (all P > 0.05). The operation time, intraoperative blood loss and fluoroscopy times of the PVP group were significantly lower than those of the PKP group (all P = 0.000). VAS score and ODI of the two groups were significantly lower at 1 d, 1 year and 2 years after surgery than before surgery (all P <0.05), but there was not statistically significant difference between the two groups at each time point after surgery (all P> 0.05). The rate of vertebral compression and kyphosis correction in the two groups were significantly corrected (P <0.05, respectively) and decreased significantly with time (all P <0.05), But there was not significant difference between the two groups at any time point (all P> 0.05). Conclusion Both PVP and PKP can achieve similar effects in the treatment of Kümmell's disease. Because the cost, operation time, blood loss, radiation exposure and surgical procedure of PVP are less than those of PKP, PVP has more clinical priority value.

Functional Radiographs of the Craniocervical Region and the Cervical Spine. A New Computer-Aided Technique

Cephalalgia ◽  
1985 ◽  
Vol 5 (4) ◽  
pp. 237-243 ◽  
Author(s):  
E Th Mayer ◽  
G Herrmann ◽  
V Pfaffenrath ◽  
W Pöllmann ◽  
Th Auberger
Keyword(s):  
Cervical Spine ◽  
Computer Program ◽  
Automatic Measuring ◽  
Computer Aided ◽  
Exact Measurement ◽  
The Individual ◽  
Adjacent Vertebra

Disabilities of the articulations of the head and cervical spine can often be detected only by exact measurement of functional radiographs. From two radiographs, one in flexion and one in extension, not only can the total mobility of the head be measured, but also the mobility of the individual articulations can be evaluated by taking exact measurements of the position of each vertebra. A method for semi-automatic measuring of such pairs of radiographs is presented. Edges and structures of the bones that are clearly visible in both radiographs are digitized on a graphics tablet. Then, by computer program, each vertebra of the first radiograph is shifted and rotated until it fits best to the respective vertebra of the second radiograph. Thus, for each articulation, the mobility angle and the location of the mobility axis relative to the adjacent vertebra, can be computed. First experiences with this method are presented.

scholarly journals Can relative rotation angle serve as a sensitive predictor for the development of adjacent segment degeneration after single-segment PLIF?

2020 ◽  
Author(s):  
Xiao Liu ◽  
Haonan Liu ◽  
Xiaosong Yang ◽  
Zhongjun Liu ◽  
xiaoguang liu ◽  
...  
Keyword(s):  
Rotation Angle ◽  
Lumbar Fusion ◽  
Measurement Data ◽  
Adjacent Segment Degeneration ◽  
Adjacent Segment ◽  
Relative Rotation ◽  
Significant Difference ◽  
Flexion Extension ◽  
Adjacent Segments ◽  
Adjacent Vertebra

Abstract Background: Adjacent segment degeneration (ASD) is a major issue after posterior lumbar interbody fusion (PLIF). Several studies have reported the potential causes of ASD based on radiography. However, the postoperative dynamic changes in the adjacent segments are not clear. This study aimed to determine the effect of PLIF on ASD using a formetric 4D system and to compare the effectiveness of this system with that of traditional radiography for the prediction of ASD. Methods: Eighty-five consecutive patients who underwent PLIF of a single-segmen t were included. The formetric 4Dsystem was used to calculate the relative rotation angle between the fusion segment and the upper and lower adjacent vertebrae preoperatively and at 6, 12 and 24 months postoperatively. The range of motion (ROM) and disc height (DH) of the adjacent segments were measured using radiography preoperatively and at 24 months postoperatively. At the final follow-up, the visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate the surgical outcome. The patients were divided into two groups according to the occurrence of radiographic ASD: the ASD group with progression of degeneration and the N-ASD group without progression of degeneration. The clinical outcomes and measurement data between the two groups were compared and analyzed. Results: The index fusion segments included L2-3 to L5-S1. Preoperatively, the relative rotation angles between the fused segment and the upper and lower adjacent vertebrae were 5.1°±2.2°and 3.3°±2.0°,respectively, and both angles increased significantly at all time-points after surgery ( p <0.05). The angles changed most significantly during L2-3 fusion . Radiographic ASD was noted in 13 of 85 patients (15.3%) at 24 months. There was no significant difference in the DH, ROM, or clinical outcome between the two groups ( p >0.05), while the relative rotation angle with the upper adjacent vertebra was greater in the ASD group than in the N-ASD group ( p <0.05). Conclusion: The relative rotation angle with the adjacent vertebra increased significantly after lumbar fusion surgery. It may be a more sensitive predictor for the development ofradiographic ASD than flexion-extension ROM and DH.

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