Dataset Information

Finite Element Analysis of a New Pedicle Screw-Plate System for Minimally Invasive Transforaminal Lumbar Interbody Fusion.

ABSTRACT:

Purpose

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is increasingly popular for the surgical treatment of degenerative lumbar disc diseases. The constructs intended for segmental stability are varied in MI-TLIF. We adopted finite element (FE) analysis to compare the stability after different construct fixations using interbody cage with posterior pedicle screw-rod or pedicle screw-plate instrumentation system.

Methods

A L3-S1 FE model was modified to simulate decompression and fusion at L4-L5 segment. Fixation modes included unilateral plate (UP), unilateral rod (UR), bilateral plate (BP), bilateral rod (BR) and UP+UR fixation. The inferior surface of the S1 vertebra remained immobilized throughout the load simulation, and a bending moment of 7.5 Nm with 400N pre-load was applied on the L3 vertebra to recreate flexion, extension, lateral bending, and axial rotation. Range of motion (ROM) and Von Mises stress were evaluated for intact and instrumentation models in all loading planes.

Results

All reconstructive conditions displayed decreased motion at L4-L5. The pedicle screw-plate system offered equal ROM to pedicle screw-rod system in unilateral or bilateral fixation modes respectively. Pedicle screw stresses for plate system were 2.2 times greater than those for rod system in left lateral bending under unilateral fixation. Stresses for plate were 3.1 times greater than those for rod in right axial rotation under bilateral fixation. Stresses on intervertebral graft for plate system were similar to rod system in unilateral and bilateral fixation modes respectively. Increased ROM and posterior instrumentation stresses were observed in all loading modes with unilateral fixation compared with bilateral fixation in both systems.

Conclusions

Transforaminal lumbar interbody fusion augmentation with pedicle screw-plate system fixation increases fusion construct stability equally to the pedicle screw-rod system. Increased posterior instrumentation stresses are observed in all loading modes with plate fixation, and bilateral fixation could reduce stress concentration.

SUBMITTER: Li J

PROVIDER: S-EPMC4674154 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Finite Element Analysis of a New Pedicle Screw-Plate System for Minimally Invasive Transforaminal Lumbar Interbody Fusion.

Li Jie J Shang Jin J Zhou Yue Y Li Changqing C Liu Huan H

PloS one 20151209 12

<h4>Purpose</h4>Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is increasingly popular for the surgical treatment of degenerative lumbar disc diseases. The constructs intended for segmental stability are varied in MI-TLIF. We adopted finite element (FE) analysis to compare the stability after different construct fixations using interbody cage with posterior pedicle screw-rod or pedicle screw-plate instrumentation system.<h4>Methods</h4>A L3-S1 FE model was modified to simula ...[more]

PMID: 26649749

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Project description:BackgroundThe previous studies agree that minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has better function outcomes, less blood loss, and shorter hospital stay, when compared to open-TLIF. However, there are no significance differences on operative time, complication, and reoperation rate between the two procedures. This could be from less relative literatures and lower grade evidence. The further meta-analysis is needed with more and higher grade evidences to compare the above two TLIF procedures.MethodsProspective and retrospective studies that compared open-TLIF and MIS-TLIF were identified by searching the Medline, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, and VIP database (the literature search comprised Medical Subject Heading terms and key words or Emtree term). The retrieval time ranged from the date when the database was founded to January 2015. Pooled risk ratios (RR s) and weighted mean differences (WMDs) with 95% confidence intervals were calculated for the clinical outcomes and perioperative data.ResultsTwenty-four studies (n = 1967 patients) were included in this review (n = 951, open-TLIF, n = 1016, MIS-TLIF). MIS-TLIF was associated with a significant decrease in the visual analog score (VAS)-back pain score (WMD = -0.44; P = 0.001), Oswestry Disabilities Index (WMD = -1.57; P = 0.005), early ambulation (WMD = -1.77; P = 0.0001), less blood loss (WMD = -265.59; P < 0.00001), and a shorter hospital stay (WMD = -1.89; P < 0.0001). However, there were no significant differences in the fusion rate (RR = 0.99; P = 0.34), VAS-leg pain (WMD = -0.10; P = 0.26), complication rate (RR = 0.84; P = 0.35), operation time (WMD = -5.23; P = 0.82), or reoperation rate (RR = 0.73; P = 0.32).ConclusionsMIS-TLIF resulted in a similar fusion rate with better functional outcome, less blood loss, shorter ambulation, and hospital stay; furthermore, it did not increase the complication or reoperation rate based on the existing evidence.

Project description:Background and Objective: Minimally Invasive Transforaminal Lumbar Interbody Fusion (MIS-TLIF) has been investigated and shown excellent short- and long-term outcomes. In this paper, we describe a new MIS-TLIF technique and pedicle screw insertion using a marker screw as a guidance method. Moreover, we report perioperative, postoperative, and patient-related outcomes. In addition, this paper outlines major differences in radiation exposure, cost effectiveness and accuracy of Marker Screw Minimally Invasive Transforaminal Interbody Fusion (MS-MIS TLIF) compared to other techniques. We report our technique to share our knowledge and experience with the aim of achieving a better MIS-TLIF that would help both surgeons and patients. Materials and Methods: A prospective case series was conducted between October 2018 and February 2021. Patients undergoing MS-MIS TLIF with marker screws were consecutively included. The surgery did not exceed two levels. The patients' medical records were reviewed, and the included patients were asked to complete two outcome-questionnaires before surgery and at the six-month visit. The surgical technique is described in this paper. Results: A total of 37 patients were recruited. The mean age was 57.35 ± 12.8 years, and more than half of the patients were females. The most common indications for surgery were degenerative disc disease and spondylolisthesis, with the typical level at L4-5. The operative time was 3.02 ± 0.83 h, while the estimated blood loss was 127.7 ± 71.1 mL. The average time for ambulation and hospitalization was 1 ± 1.1 and 2.84 ± 1.4 days, respectively. The patients described significant improvement in both questionnaires. No screw-related complications or screw revisions were needed up to two years of follow-up. Conclusions: The use of marker screws for pedicle screw placement through a minimally invasive fashion is shown to be a promising technique that can overcome many drawbacks, including cost, operative time, and radiation exposure. Performing MS-MIS TLIF can achieve a 360- degree fusion compared to percutaneous MIS-TLIF.

Project description:BackgroundTransforaminal lumbar interbody fusion (TLIF) has become one of the most widely used procedures for lumbar spinal disorders. However, it is still unclear whether TLIF with unilateral pedicle screw (PS) fixation is as effective as that with bilateral PS fixation. We performed a meta-analysis of the literatures and aimed to gain a better understanding of whether TLIF with unilateral PS fixation was safe and effective for lumbar diseases.Methodology/principal findingsWe systematically searched Ovid, Springer, and Medline databases for relevant randomized controlled trials (RCTs) that compared the clinical and radiological outcomes of unilateral versus bilateral PS fixation in TLIF. Risk of bias in included studies was assessed using the Cochrane Risk of Bias tool. We generated pooled risk ratios or weighted mean differences across studies. According to our predefined inclusion criteria, seven RCTs with a total of 441 patients were included in this study. Baseline characteristics were similar between the unilateral and bilateral groups. Our meta-analysis showed that no significant difference was detected between the two groups in terms of postoperative clinical function, fusion status, reoperation rate, complication rate, and hospital stay (p>0.05). Pooled estimates revealed that the unilateral group was associated with significantly reduced implant cost, operative time and blood loss (p<0.05).Conclusions/significancesOur meta-analysis suggested TLIF with unilateral PS fixation was as safe and effective as that with bilateral PS fixation for lumbar diseases in selected patients. Despite these findings, our meta-analysis was based on studies with small sample size and different study characteristics that might lead to the inconsistent results such as various functional outcomes among the included studies. Therefore, high-quality randomized controlled trials with larger sample size are also needed to further clarify these issues and to provide the long-term outcomes.

Project description:STUDY DESIGN:Retrospective case series. OBJECTIVE:To describe a modified technique for mini-open transforaminal lumbar interbody fusion (TLIF) that improves visualization for decompression, fusion, and freehand pedicle screw insertion. Accuracy of freehand pedicle screw placement with this technique was assessed. SUMMARY OF BACKGROUND DATA:Mini-open TLIF is a minimally invasive technique that allows limited visualization of the bone and neural anatomy via an expandable tubular retractor inserted through the Wiltse plane. No significant modification that of this technique has been described in detail. METHODS:In this study, 92 consecutive patients underwent one-level modified mini-open TLIF (MOTLIF). MOTLIF modifications consisted of (i) transmuscular dissection through the multifidus muscle rather than intermuscular dissection in the Wiltse plane; (ii) microsurgical detachment of multifidus from the facet rather than muscle dilation; (iii) en bloc total facetectomy (unilateral or bilateral, as needed for decompression); (iv) facet autograft used for interbody fusion; and (v) solid pedicle screws placed bilaterally by a freehand technique under direct vision. RESULTS:The mean age was 53 years. Mean follow-up was 35 months (minimum 2 yrs). By 6 months, mean Visual Analog Scale for back and leg pain had improved from 51 to 19 and from 58 to 17, respectively, and mean Oswestry Disability Index (ODI) improved from 53 to 16. These improvements persisted at 2 years. Solid fusion, defined by computed tomography at 1 year, was achieved in 88.1%, whereas satisfactory fusion was achieved in 95.2% of patients. Pedicle screws were accurately placed in 335 of 336 imaged pedicles (pedicle breach grades: 91.1% grade 1; 8.6% grade 2; and 0.3% grade 3). Mean fluoroscopy time was 29.3?seconds. CONCLUSION:MOTLIF is a safe and effective minimally invasive technique with a high fusion rate. It allows accurate pedicle screw placement by a freehand technique. By eliminating bi-planar fluoroscopy, it helps reduce radiation exposure. This is the largest published report of mini-open TLIF to date. LEVEL OF EVIDENCE:4.

Project description:BackgroundMinimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and oblique lateral interbody fusion (OLIF) are widely used in the treatment of lumbar degenerative diseases. In the present study, a meta-analysis was conducted to compare the clinical and radiographic efficacy of these two procedures.MethodsA systematic literature review was performed, and the quality of retrieved studies was evaluated with the Newcastle-Ottawa Scale (NOS). Clinical outcomes, including operation time, intraoperative blood loss, improvement in Visual Analogue Scale (VAS), improvement in Oswestry Disability Index (ODI), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) effectiveness rate and complications, in addition to radiographic outcomes, including restoration of disc height, disc angle, overall lumbar lordosis, fusion rate and subsidence, were extracted and input into a fixed or random effect model to compare the efficacy of MIS-TLIF and OLIF.ResultsSeven qualified studies were included. Clinically, OLIF resulted in less intraoperative blood loss and shorter operation time than MIS-TLIF. Improvement of VAS for leg pain was more obvious in the OLIF group (P < 0.0001), whereas improvement of VAS for back pain (P = 0.08) and ODI (P = 0.98) as well as JOABPEQ effectiveness rate (P = 0.18) were similar in the two groups. Radiographically, OLIF was more effective in restoring disc height (P = 0.01) and equivalent in improving the disc angle (P = 0.18) and lumbar lordosis (P = 0.48) compared with MIS-TLIF. The fusion rate (P = 0.11) was similar in both groups, while the subsidence was more severe in the MIS-TLIF group (P < 0.00001).ConclusionsThe above evidence suggests that OLIF is associated with a shorter operation time (with supplementary fixation in the prone position) and less intraoperative blood loss than MIS-TLIF and can lead to better leg pain alleviation, disc height restoration and subsidence resistance. No differences regarding back pain relief, functional recovery, complications, disc angle restoration, lumbar lordosis restoration and fusion rate were found. However, due to the limited number of studies, our results should be confirmed with high-level studies to fully compare the therapeutic efficacy of MIS-TLIF and OLIF.Trial registrationPROSPERO ID: CRD42020201903 .

Project description:ObjectiveThe objective of this study is to compare the clinical efficacy of O-arm navigation and microscope-assisted minimally invasive transforaminal lumbar interbody fusion (modified MIS-TLIF) versus conventional TLIF in the lumbar isthmic spondylolisthesis.Materials and methodsForty patients with 1-level lumbar isthmic spondylolisthesis were enrolled in the study. Perioperative indexes including operation time, intraoperative bleeding, bed rest time, time of hospitalisation stay and the accuracy rate of screw placement were analysed. Preoperative and postoperative visual analogue scale (VAS) and Oswestry disability index (ODI) were assessed.ResultsThe operation time in the modified MIS-TLIF group was longer than the conventional TLIF group (p < 0.05). However, intraoperative blood loss in the modified MIS-TLIF group was less than the comparative group (p < 0.05). The average bed rest time and hospitalisation stay in the modified MIS-TLIF group was shorter than conventional TLIF group (p < 0.05). The screw placement in the modified MIS-TLIF group was more precisely than that in the conventional TLIF group (p < 0.05). Meanwhile, the improvement of VAS and ODI in the modified MIS-TLIF group were lower than that in the conventional TLIF group 1 and 6 months after operation (p < 0.05). There was no difference in the VAS and ODI score between the two group at the last follow-up (p > 0.05).ConclusionNavigation and microscope-assisted MIS-TLIF is safe and reliable for treatment of lumbar isthmic spondylolisthesis (Meyerding degree I or II) with potential advantages including less injury, less blood loss, higher screw accuracy and faster recovery after operation.The translational potential of this articleCompared with conventional transforaminal lumbar interbody fusion, O-arm navigation and microscope-assisted minimally invasive transforaminal lumbar interbody fusion has a huge advantage in surgery treatment of lumbar isthmic spondylolisthesis. Hence, this article provided a better surgery method to deal with lumbar isthmic spondylolisthesis, and robot-assisted minimally invasive transforaminal lumbar interbody fusion will be adopted in the future.

Dataset Information

Finite Element Analysis of a New Pedicle Screw-Plate System for Minimally Invasive Transforaminal Lumbar Interbody Fusion.

Purpose

Methods

Results

Conclusions

Publications

Finite Element Analysis of a New Pedicle Screw-Plate System for Minimally Invasive Transforaminal Lumbar Interbody Fusion.

Similar Datasets

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