scholarly journals CORRELATION: IMPEDANCE AND TOMOGRAPHY IN IMPLANTS INSERTION IN LUMBAR ARTHRODESIS

2016 ◽  
Vol 15 (4) ◽  
pp. 283-286
Author(s):  
ÉRIKO GONÇALVES FILGUEIRA ◽  
LUCIANO DE ALMEIDA FERRER ◽  
ITAMAR ALVES BARBOSA NETO ◽  
LEONARDO MORAIS PAIVA ◽  
RICARDO SUGAI ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Quantitative Method ◽  
Pedicle Screws ◽  
Perioperative Period ◽  
Nerve Roots ◽  
Safe Method ◽  
Risk Of Injury ◽  
Post Operative Period ◽  
Lumbar Arthrodesis ◽  
Retrospective Multicenter Study

ABSTRACT Objective: To define whether the electroneurophysiological stimulation would be a safe method for reducing injuries in nerve roots during surgery of lumbar spine arthrodesis, as well as verify whether there is a direct correlation between the intraoperative impedance values and the distance from the medial cortical pedicle screw. Methods: Randomized retrospective multicenter study of 10 patients who underwent arthrodesis of lumbar spine after conservative treatment failure, with a total of 50 pedicle screws instrumented. Reliable and safe impedance values were measured in order to reduce the risk of injury to nerve roots in the perioperative period, and these values were compared with the distance between the screw and the medial cortical of the pedicle by CT scan, measured in the immediate post-operative period. Results: There is no direct correlation between the intraoperative impedance values and the distance from the screw to the medial cortical of the pedicle. Conclusion: The electroneurostimulation proved to be a reliable quantitative method to reduce the risk of injury to nerve roots during surgery of lumbar spine arthrodesis when the measured values are greater than 10mA.

scholarly journals Gravity determines the direction of nerve roots sedimentation in the lumbar spinal canal

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jun Yang ◽  
Zhiyun Feng ◽  
Nian Chen ◽  
Zhenhua Hong ◽  
Yongyu Zheng ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Mr Imaging ◽  
Spinal Canal ◽  
Ventral Side ◽  
Lateral Position ◽  
Dorsal Side ◽  
Mr Images ◽  
Nerve Roots ◽  
Cross Sectional ◽  
Dural Sac

Abstract Objectives To investigate the role of gravity in the sedimentation of lumbar spine nerve roots using magnetic resonance (MR) imaging of various body positions. Methods A total of 56 patients, who suffered from back pain and underwent conventional supine lumbar spine MR imaging, were selected from sanmen hospital database. All the patients were called back to our hospital to perform MR imaging in prone position or lateral position. Furthermore, the sedimentation sign (SedSign) was determined based on the suspension of the nerve roots in the dural sac on cross-sectional MR images, and 31 cases were rated as positive and another 25 cases were negative. Results The mean age of negative SedSign group was significantly younger than that of positive SedSign group (51.7 ± 8.7 vs 68.4 ± 10.5, P < 0.05). The constitutions of clinical diagnosis were significantly different between patients with a positive SedSign and those with a negative SedSign (P < 0.001). Overall, nerve roots of the vast majority of patients (48/56, 85.7%) subsided to the ventral side of the dural sac on the prone MR images, although that of 8 (14.3%) patients remain stay in the dorsal side of dural sac. Nerve roots of only one patient with negative SedSign did not settle to the ventral dural sac, while this phenomenon occurred in 7 patients in positive SedSign group (4% vs 22.6%, P < 0.001). In addition, the nerve roots of all the five patients subsided to the left side of dural sac on lateral position MR images. Conclusions The nerve roots sedimentation followed the direction of gravity. Positive SedSign may be a MR sign of lumbar pathology involved the spinal canal.

A comparative study on screw loosening in osteoporotic lumbar spine fusion between expandable and conventional pedicle screws

2011 ◽  
Vol 132 (4) ◽  
pp. 471-476 ◽  
Author(s):  
Zi-xiang Wu ◽  
Fu-tai Gong ◽  
Li Liu ◽  
Zhen-sheng Ma ◽  
Yang Zhang ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Comparative Study ◽  
Pedicle Screws ◽  
Spine Fusion ◽  
Screw Loosening ◽  
Lumbar Spine Fusion

Hybrid dynamic stabilization: a biomechanical assessment of adjacent and supraadjacent levels of the lumbar spine

2012 ◽  
Vol 17 (3) ◽  
pp. 232-242 ◽  
Author(s):  
Prasath Mageswaran ◽  
Fernando Techy ◽  
Robb W. Colbrunn ◽  
Tara F. Bonner ◽  
Robert F. McLain
Keyword(s):  
Lumbar Spine ◽  
Lumbar Fusion ◽  
Industrial Robot ◽  
Pedicle Screws ◽  
Axial Rotation ◽  
Dynamic Stabilization ◽  
Follower Load ◽  
Lateral Bending ◽  
Intact Specimen ◽  
Flexion Extension

Object The object of this study was to evaluate the effect of hybrid dynamic stabilization on adjacent levels of the lumbar spine. Methods Seven human spine specimens from T-12 to the sacrum were used. The following conditions were implemented: 1) intact spine; 2) fusion of L4–5 with bilateral pedicle screws and titanium rods; and 3) supplementation of the L4–5 fusion with pedicle screw dynamic stabilization constructs at L3–4, with the purpose of protecting the L3–4 level from excessive range of motion (ROM) and to create a smoother motion transition to the rest of the lumbar spine. An industrial robot was used to apply continuous pure moment (± 2 Nm) in flexion-extension with and without a follower load, lateral bending, and axial rotation. Intersegmental rotations of the fused, dynamically stabilized, and adjacent levels were measured and compared. Results In flexion-extension only, the rigid instrumentation at L4–5 caused a 78% decrease in the segment's ROM when compared with the intact specimen. To compensate, it caused an increase in motion at adjacent levels L1–2 (45.6%) and L2–3 (23.2%) only. The placement of the dynamic construct at L3–4 decreased the operated level's ROM by 80.4% (similar stability as the fusion at L4–5), when compared with the intact specimen, and caused a significant increase in motion at all tested adjacent levels. In flexion-extension with a follower load, instrumentation at L4–5 affected only a subadjacent level, L5–sacrum (52.0%), while causing a reduction in motion at the operated level (L4–5, −76.4%). The dynamic construct caused a significant increase in motion at the adjacent levels T12–L1 (44.9%), L1–2 (57.3%), and L5–sacrum (83.9%), while motion at the operated level (L3–4) was reduced by 76.7%. In lateral bending, instrumentation at L4–5 increased motion at only T12–L1 (22.8%). The dynamic construct at L3–4 caused an increase in motion at T12–L1 (69.9%), L1–2 (59.4%), L2–3 (44.7%), and L5–sacrum (43.7%). In axial rotation, only the placement of the dynamic construct at L3–4 caused a significant increase in motion of the adjacent levels L2–3 (25.1%) and L5–sacrum (31.4%). Conclusions The dynamic stabilization system displayed stability characteristics similar to a solid, all-metal construct. Its addition of the supraadjacent level (L3–4) to the fusion (L4–5) did protect the adjacent level from excessive motion. However, it essentially transformed a 1-level lumbar fusion into a 2-level lumbar fusion, with exponential transfer of motion to the fewer remaining discs.

scholarly journals Confirmation of accuracy/inaccuracy of lumbar pedicle screw placement using postoperative computed tomography

2021 ◽  
Vol 12 ◽  
pp. 518
Author(s):  
Mohamed M. Arnaout ◽  
Magdy O. ElSheikh ◽  
Mansour A. Makia
Keyword(s):  
Computed Tomography ◽  
Lumbar Spine ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Operative Intervention ◽  
Screw Placement ◽  
Lumbar Spine Surgery ◽  
Pedicle Screw Placement ◽  
Lumbar Pedicle ◽  
Ct Studies

Background: Transpedicular screws are extensively utilized in lumbar spine surgery. The placement of these screws is typically guided by anatomical landmarks and intraoperative fluoroscopy. Here, we utilized 2-week postoperative computed tomography (CT) studies to confirm the accuracy/inaccuracy of lumbar pedicle screw placement in 145 patients and correlated these findings with clinical outcomes. Methods: Over 6 months, we prospectively evaluated the location of 612 pedicle screws placed in 145 patients undergoing instrumented lumbar fusions addressing diverse pathology with instability. Routine anteroposterior and lateral plain radiographs were obtained 48 h after the surgery, while CT scans were obtained at 2 postoperative weeks (i.e., ideally these should have been performed intraoperatively or within 24–48 h of surgery). Results: Of the 612 screws, minor misplacement of screws (≤2 mm) was seen in 104 patients, moderate misplacement in 34 patients (2–4 mm), and severe misplacement in 7 patients (>4 mm). Notably, all the latter 7 (4.8% of the 145) patients required repeated operative intervention. Conclusion: Transpedicular screw insertion in the lumbar spine carries the risks of pedicle medial/lateral violation that is best confirmed on CT rather than X-rays/fluoroscopy alone. Here, we additional found 7 patients (4.8%) who with severe medial/lateral pedicle breach who warranting repeated operative intervention. In the future, CT studies should be performed intraoperatively or within 24–48 h of surgery to confirm the location of pedicle screws and rule in our out medial or lateral pedicle breaches.

scholarly journals Biochemical and Haemodynamic Effects of Crystalloid Solutions Administered During Perioperative Period

2009 ◽  
pp. 33-37
Author(s):  
Debasish Banik ◽  
Qumrul Huda ◽  
Abdul Hye ◽  
KM Iqbal
Keyword(s):  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Pulse Rate ◽  
Normal Saline ◽  
Urine Output ◽  
Perioperative Period ◽  
The Body ◽  
Post Operative Period ◽  
Significant Difference ◽  
Group A

Forty five (45) ASA grade I & II patients aged between 21 to 55 years, scheduled for electiv abdominal surgery (incision not exceeding 15 cm with minimal blood loss, under general anaesthesia were randomly allocated into three groups (A, and C). Patients of Group A, B and C received infusion of 5% dextrose aqua, normal saline and 5% dextrose in normal saline respectively throughout perioperative course (upto 24 hours after operation). Each group received post operative period. Parameters recorded were mean arterial pressure (MAP), Pulse, Serum elecirolyte (Na+, K+), amount of fluid in fused and urine output during operation and postoperatively Blood samples for serum electrolyte estimation were taken just before induction, immediately before reversal and twenty four hours after surgery. A standard anaesthetic technique was followed for all groups.Percentage increase from pre-operative values were calculated for mean arterial pressure, pulse rate and serum electrolytes. The ratio between urine output and fluid infused during per- and post-operative period were calculated. There were statistically significant (p<0.05) difference between group A and C in perand post-operative change in pulse rate and statistically significant difference (p<0.05) in postoperative output/input ratio between group A and B and highly significant (p<0.01) between A and C. Electrolyte containing fluids of higher osmolality caused increased diuresis in per-operative period and increased pulse rate in post-operative period. So, although there are few difference between three fluids, these didnot produce any effects( beneficial or detrimental) on the body system under normal conditions. Journal of BSA, Vol. 19, No. 1 & 2, 2006 p.33-37

scholarly journals Pedicle Screws Loosening in Patients With Degenerative Diseases of the Lumbar Spine: Potential Risk Factors and Relative Contribution

2018 ◽  
Vol 9 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Andrey Bokov ◽  
Anatoliy Bulkin ◽  
Alexander Aleynik ◽  
Marina Kutlaeva ◽  
Sergey Mlyavykh
Keyword(s):  
Risk Factors ◽  
Lumbar Spine ◽  
Potential Risk ◽  
Pedicle Screws ◽  
Degenerative Diseases ◽  
Relative Contribution ◽  
Potential Risk Factors

Optimization of Pedicle Screw Depth in the Lumbar Spine

2013 ◽  
Author(s):  
Laura E. Buckenmeyer ◽  
Kristophe J. Karami ◽  
Ata M. Kiapour ◽  
Vijay K. Goel ◽  
Teck M. Soo ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Fixation Strength ◽  
Osteoporotic Patient ◽  
Insertion Depth ◽  
Anterior Cortex ◽  
Screw Insertion ◽  
Clinical Challenge ◽  
Series Of Experiments

Optimization of pedicle screw insertion depth for ideal fixation and fusion remains a clinical challenge. Improved screw purchase may improve fixation strength 1, which is especially critical in an osteoporotic patient population. Extended screw insertion depths, up to and through the anterior cortex, have yet to be compared to more commonly used shorter pedicle screws in a laboratory controlled series of experiments. The purpose of this study is to evaluate screw purchase in the osteoporotic lumbar spine as a function of insertion depth, which may be used to optimize pedicle screw-rod constructs.

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