Muzammil Mumtaz, Andrew P Collins, Niloufar Shekouhi, Karthika Varier, Sudharshan Tripathi, Christopher P Ames, Vedat Deviren, Aaron J Clark, Vijay K Goel, Alekos A Theologis
{"title":"骨盆固定策略和多杆结构对长胸腰椎后路器械融合术近端交界处生物力学的影响:有限元分析。","authors":"Muzammil Mumtaz, Andrew P Collins, Niloufar Shekouhi, Karthika Varier, Sudharshan Tripathi, Christopher P Ames, Vedat Deviren, Aaron J Clark, Vijay K Goel, Alekos A Theologis","doi":"10.1007/s43390-024-00932-w","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>To assess the effect of various pelvic fixation techniques and number of rods on biomechanics of the proximal junction of long thoracolumbar posterior instrumented fusions.</p><p><strong>Methods: </strong>A validated spinopelvic finite-element (FE) model was instrumented with L5-S1 ALIF and one of the following 9 posterior instrumentation configurations: (A) one traditional iliac screw bilaterally (\"2 Iliac/2 Rods\"); (B) T10 to S1 (\"Sacral Only\"); (C) unilateral traditional iliac screw (\"1 Iliac/2 Rods\"); (D) one traditional iliac screw bilaterally with one midline accessory rod (\"2 Iliac/3 rods\"); (E) S2AI screws connected directly to the midline rods (\"2 S2AI/2 Rods\"); and two traditional iliac screws bilaterally with two lateral accessory rods connected to the main rods at varying locations (F1: T10-11, F2: T11-12, F3: T12-L1, F4: L1-2) (\"4 Iliac/4 Rods\"). Range of motions (ROM) at T10-S1 and T9-T10 were recorded and compared between models. The T9-T10 intradiscal pressures and stresses of the T9-10 disc's annulus in addition to the von Mises stresses of the T9 and T10 vertebral bodies were recorded and compared.</p><p><strong>Results: </strong>For T10-S1 ROM, 4 iliac/4 rods had lowest ROM in flexion and extension, while 2 S2AI/2 rods showed lowest ROM in rotation. Constructs with 3 or 4 rods had lower stresses on the primary rods compared to 2-rod constructs. At the proximal adjacent disc (T9-10), 4 iliac/4 rods showed lowest ROM, lowest intradiscal pressures, and lowest annular stress in all directions (most pronounced in flexion-extension). Under flexion and extension, 4 iliac/4 rods also showed the lowest von Mises stresses on the T10 vertebral body but the highest stresses on the T9 vertebral body.</p><p><strong>Conclusions: </strong>Dual iliac screws with 4 rods across the lumbosacral junction and extending to the thoracolumbar junction demonstrated the lowest T10-S1 ROM, the lowest adjacent segment disc (T9-T10) ROM, intradiscal pressures, and annular stresses, and the lowest UIV stresses, albeit with the highest UIV + 1 stresses. Additional studies are needed to confirm whether these biomechanical findings dictate clinical outcomes and effect rates of proximal junctional kyphosis and failure.</p>","PeriodicalId":21796,"journal":{"name":"Spine deformity","volume":null,"pages":null},"PeriodicalIF":1.6000,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11499539/pdf/","citationCount":"0","resultStr":"{\"title\":\"Effects of pelvic fixation strategies and multi-rod constructs on biomechanics of the proximal junction in long thoracolumbar posterior instrumented fusions: a finite-element analysis.\",\"authors\":\"Muzammil Mumtaz, Andrew P Collins, Niloufar Shekouhi, Karthika Varier, Sudharshan Tripathi, Christopher P Ames, Vedat Deviren, Aaron J Clark, Vijay K Goel, Alekos A Theologis\",\"doi\":\"10.1007/s43390-024-00932-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Purpose: </strong>To assess the effect of various pelvic fixation techniques and number of rods on biomechanics of the proximal junction of long thoracolumbar posterior instrumented fusions.</p><p><strong>Methods: </strong>A validated spinopelvic finite-element (FE) model was instrumented with L5-S1 ALIF and one of the following 9 posterior instrumentation configurations: (A) one traditional iliac screw bilaterally (\\\"2 Iliac/2 Rods\\\"); (B) T10 to S1 (\\\"Sacral Only\\\"); (C) unilateral traditional iliac screw (\\\"1 Iliac/2 Rods\\\"); (D) one traditional iliac screw bilaterally with one midline accessory rod (\\\"2 Iliac/3 rods\\\"); (E) S2AI screws connected directly to the midline rods (\\\"2 S2AI/2 Rods\\\"); and two traditional iliac screws bilaterally with two lateral accessory rods connected to the main rods at varying locations (F1: T10-11, F2: T11-12, F3: T12-L1, F4: L1-2) (\\\"4 Iliac/4 Rods\\\"). Range of motions (ROM) at T10-S1 and T9-T10 were recorded and compared between models. The T9-T10 intradiscal pressures and stresses of the T9-10 disc's annulus in addition to the von Mises stresses of the T9 and T10 vertebral bodies were recorded and compared.</p><p><strong>Results: </strong>For T10-S1 ROM, 4 iliac/4 rods had lowest ROM in flexion and extension, while 2 S2AI/2 rods showed lowest ROM in rotation. Constructs with 3 or 4 rods had lower stresses on the primary rods compared to 2-rod constructs. At the proximal adjacent disc (T9-10), 4 iliac/4 rods showed lowest ROM, lowest intradiscal pressures, and lowest annular stress in all directions (most pronounced in flexion-extension). Under flexion and extension, 4 iliac/4 rods also showed the lowest von Mises stresses on the T10 vertebral body but the highest stresses on the T9 vertebral body.</p><p><strong>Conclusions: </strong>Dual iliac screws with 4 rods across the lumbosacral junction and extending to the thoracolumbar junction demonstrated the lowest T10-S1 ROM, the lowest adjacent segment disc (T9-T10) ROM, intradiscal pressures, and annular stresses, and the lowest UIV stresses, albeit with the highest UIV + 1 stresses. Additional studies are needed to confirm whether these biomechanical findings dictate clinical outcomes and effect rates of proximal junctional kyphosis and failure.</p>\",\"PeriodicalId\":21796,\"journal\":{\"name\":\"Spine deformity\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.6000,\"publicationDate\":\"2024-11-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11499539/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Spine deformity\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1007/s43390-024-00932-w\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2024/8/20 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q3\",\"JCRName\":\"CLINICAL NEUROLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Spine deformity","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s43390-024-00932-w","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/8/20 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"CLINICAL NEUROLOGY","Score":null,"Total":0}
Effects of pelvic fixation strategies and multi-rod constructs on biomechanics of the proximal junction in long thoracolumbar posterior instrumented fusions: a finite-element analysis.
Purpose: To assess the effect of various pelvic fixation techniques and number of rods on biomechanics of the proximal junction of long thoracolumbar posterior instrumented fusions.
Methods: A validated spinopelvic finite-element (FE) model was instrumented with L5-S1 ALIF and one of the following 9 posterior instrumentation configurations: (A) one traditional iliac screw bilaterally ("2 Iliac/2 Rods"); (B) T10 to S1 ("Sacral Only"); (C) unilateral traditional iliac screw ("1 Iliac/2 Rods"); (D) one traditional iliac screw bilaterally with one midline accessory rod ("2 Iliac/3 rods"); (E) S2AI screws connected directly to the midline rods ("2 S2AI/2 Rods"); and two traditional iliac screws bilaterally with two lateral accessory rods connected to the main rods at varying locations (F1: T10-11, F2: T11-12, F3: T12-L1, F4: L1-2) ("4 Iliac/4 Rods"). Range of motions (ROM) at T10-S1 and T9-T10 were recorded and compared between models. The T9-T10 intradiscal pressures and stresses of the T9-10 disc's annulus in addition to the von Mises stresses of the T9 and T10 vertebral bodies were recorded and compared.
Results: For T10-S1 ROM, 4 iliac/4 rods had lowest ROM in flexion and extension, while 2 S2AI/2 rods showed lowest ROM in rotation. Constructs with 3 or 4 rods had lower stresses on the primary rods compared to 2-rod constructs. At the proximal adjacent disc (T9-10), 4 iliac/4 rods showed lowest ROM, lowest intradiscal pressures, and lowest annular stress in all directions (most pronounced in flexion-extension). Under flexion and extension, 4 iliac/4 rods also showed the lowest von Mises stresses on the T10 vertebral body but the highest stresses on the T9 vertebral body.
Conclusions: Dual iliac screws with 4 rods across the lumbosacral junction and extending to the thoracolumbar junction demonstrated the lowest T10-S1 ROM, the lowest adjacent segment disc (T9-T10) ROM, intradiscal pressures, and annular stresses, and the lowest UIV stresses, albeit with the highest UIV + 1 stresses. Additional studies are needed to confirm whether these biomechanical findings dictate clinical outcomes and effect rates of proximal junctional kyphosis and failure.
期刊介绍:
Spine Deformity the official journal of the?Scoliosis Research Society is a peer-refereed publication to disseminate knowledge on basic science and clinical research into the?etiology?biomechanics?treatment?methods and outcomes of all types of?spinal deformities. The international members of the Editorial Board provide a worldwide perspective for the journal's area of interest.The?journal?will enhance the mission of the Society which is to foster the optimal care of all patients with?spine?deformities worldwide. Articles published in?Spine Deformity?are Medline indexed in PubMed.? The journal publishes original articles in the form of clinical and basic research. Spine Deformity will only publish studies that have institutional review board (IRB) or similar ethics committee approval for human and animal studies and have strictly observed these guidelines. The minimum follow-up period for follow-up clinical studies is 24 months.