Pub Date : 2009-09-01DOI: 10.1016/j.esas.2009.09.004
F. Grados , C. Depriester , G. Cayrolle , N. Hardy , H. Deramond , P. Fardellone
Objective
To assess the immediate and long-term efficacy and safety of percutaneous vertebroplasty with polymethylmethacrylate (PMMA) for the treatment of refractory pain resulting from osteoporotic vertebral fractures.
Methods
A retrospective, open study of percutaneous vertebroplasty (PV) was conducted with long-term follow-up. PV with PMMA was carried out between 1990 and 1996 in 40 patients with symptomatic osteoporotic vertebral fracture(s) that had not responded to maximum medical therapy. In 1997, each patient was asked to come back to our institution for a physical and spinal X-ray examination. Efficacy was assessed by changes over time in pain on Huskisson's visual analogue scale (VAS).
Results
Thirty-four vertebrae treated by PV in 25 patients were evaluated with long-term follow-up. The mean duration of follow-up was 48 months (range 12–84 months). Pain assessed by the VAS significantly (P < 0.05) decreased from a mean of 80 mm ± 16 (S.D.) before PV to 37 ± 24 mm after 1 month and 34 ± 28 mm at the time of maximal follow-up. There was no severe complication related to this treatment, and no progression of vertebral deformity in any of the injected vertebrae. However, there was a slight but significantly increased risk of vertebral fracture in the vicinity of a cemented vertebra (odds ratio 2.27, 95% confidence interval 1.1–4.56).The odds ratio of a vertebral fracture in the vicinity of an uncemented fractured vertebra was 1.44 (0.82–2.55).
Conclusion
PV appears to be a safe and useful procedure for the treatment of focal back pain secondary to osteoporotic vertebral fracture when conservative treatment has failed.
{"title":"Long-term observations of vertebral osteoporotic fractures treated by percutaneous vertebroplasty","authors":"F. Grados , C. Depriester , G. Cayrolle , N. Hardy , H. Deramond , P. Fardellone","doi":"10.1016/j.esas.2009.09.004","DOIUrl":"https://doi.org/10.1016/j.esas.2009.09.004","url":null,"abstract":"<div><h3>Objective</h3><p>To assess the immediate and long-term efficacy and safety of percutaneous vertebroplasty with polymethylmethacrylate (PMMA) for the treatment of refractory pain resulting from osteoporotic vertebral fractures.</p></div><div><h3>Methods</h3><p>A retrospective, open study of percutaneous vertebroplasty (PV) was conducted with long-term follow-up. PV with PMMA was carried out between 1990 and 1996 in 40 patients with symptomatic osteoporotic vertebral fracture(s) that had not responded to maximum medical therapy. In 1997, each patient was asked to come back to our institution for a physical and spinal X-ray examination. Efficacy was assessed by changes over time in pain on Huskisson's visual analogue scale (VAS).</p></div><div><h3>Results</h3><p>Thirty-four vertebrae treated by PV in 25 patients were evaluated with long-term follow-up. The mean duration of follow-up was 48 months (range 12–84 months). Pain assessed by the VAS significantly (<em>P</em> < 0.05) decreased from a mean of 80 mm ± 16 (S.D.) before PV to 37 ± 24 mm after 1 month and 34 ± 28 mm at the time of maximal follow-up. There was no severe complication related to this treatment, and no progression of vertebral deformity in any of the injected vertebrae. However, there was a slight but significantly increased risk of vertebral fracture in the vicinity of a cemented vertebra (odds ratio 2.27, 95% confidence interval 1.1–4.56).The odds ratio of a vertebral fracture in the vicinity of an uncemented fractured vertebra was 1.44 (0.82–2.55).</p></div><div><h3>Conclusion</h3><p>PV appears to be a safe and useful procedure for the treatment of focal back pain secondary to osteoporotic vertebral fracture when conservative treatment has failed.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 118-122"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91631724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-09-01DOI: 10.1016/j.esas.2009.09.003
Donna D. Ohnmeiss Dr.Med, Richard D. Guyer MD
Background
Traditionally, spine societies and journals have set guidelines requiring a minimum 24-month follow-up for reporting results of surgical implant studies. However, the basis for this particular time period is not clear. The purpose of this study was to analyze prospective spinal implant studies reporting data at multiple specific follow-up periods to determine if there were significant changes in the clinical outcome throughout the 24-month follow-up period.
Methods
A comprehensive literature search was conducted using PubMed as well as searching the FDA web page. Studies were evaluated to identify those meeting the inclusion criteria: involved at least 100 patients receiving a spinal implant with data reported at multiple pre-defined time periods post-operatively for at least 24-months. Data recorded from each study included, number of patients, diagnoses, implant used, outcome measures used, and the results reported. The primary outcome data were analyzed in the current study to determine the amount of change in scores, with particular focus on the six and 24-month follow-up periods.
Results
Only 7 studies met the inclusion criteria. All seven studies were FDA-regulated trials published since 1997. Six addressed the treatment of symptomatic disc degeneration and 1 involved patients with neurogenic claudication due to stenosis. The outcome measures in the studies varied but pain and function were frequently assessed. In none of the studies was there a significant deterioration in results between the 6 and 24-month follow-up periods. In fact, the only changes during the follow-up periods were slight, not statistically significant, improvements, with the exception of 1 scale in 1 study where a slight, not statistically significant, decrease in the extent of improvement on a physical function assessment was noted between 6 and 24 months. These results suggest a great deal of stability in the mean scores for various outcome measures between the 6 and 24 months in patients receiving spinal implants.
Conclusions
Although long-term follow-up is certainly desirable for any clinical outcome study, there appears to be no significant change in outcome measures between the 6-month and 24-month follow-ups. These results support that earlier dissemination of results may be appropriate without producing overly-optimistic reports.
{"title":"Twenty-four month follow-up for reporting results of spinal implant studies: Is this guideline supported by the literature?","authors":"Donna D. Ohnmeiss Dr.Med, Richard D. Guyer MD","doi":"10.1016/j.esas.2009.09.003","DOIUrl":"10.1016/j.esas.2009.09.003","url":null,"abstract":"<div><h3>Background</h3><p>Traditionally, spine societies and journals have set guidelines requiring a minimum 24-month follow-up for reporting results of surgical implant studies. However, the basis for this particular time period is not clear. The purpose of this study was to analyze prospective spinal implant studies reporting data at multiple specific follow-up periods to determine if there were significant changes in the clinical outcome throughout the 24-month follow-up period.</p></div><div><h3>Methods</h3><p>A comprehensive literature search was conducted using PubMed as well as searching the FDA web page. Studies were evaluated to identify those meeting the inclusion criteria: involved at least 100 patients receiving a spinal implant with data reported at multiple pre-defined time periods post-operatively for at least 24-months. Data recorded from each study included, number of patients, diagnoses, implant used, outcome measures used, and the results reported. The primary outcome data were analyzed in the current study to determine the amount of change in scores, with particular focus on the six and 24-month follow-up periods.</p></div><div><h3>Results</h3><p>Only 7 studies met the inclusion criteria. All seven studies were FDA-regulated trials published since 1997. Six addressed the treatment of symptomatic disc degeneration and 1 involved patients with neurogenic claudication due to stenosis. The outcome measures in the studies varied but pain and function were frequently assessed. In none of the studies was there a significant deterioration in results between the 6 and 24-month follow-up periods. In fact, the only changes during the follow-up periods were slight, not statistically significant, improvements, with the exception of 1 scale in 1 study where a slight, not statistically significant, decrease in the extent of improvement on a physical function assessment was noted between 6 and 24 months. These results suggest a great deal of stability in the mean scores for various outcome measures between the 6 and 24 months in patients receiving spinal implants.</p></div><div><h3>Conclusions</h3><p>Although long-term follow-up is certainly desirable for any clinical outcome study, there appears to be no significant change in outcome measures between the 6-month and 24-month follow-ups. These results support that earlier dissemination of results may be appropriate without producing overly-optimistic reports.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 100-107"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33155945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An artificial disc prosthesis is thought to restore segmental motion in the lumbar spine. However, it is reported that disc prosthesis can increase the intervertebral translation (VT). The concept of the mobile-core prosthesis is to mimic the kinematic effects of the migration of the natural nucleus and therefore core mobility should minimize the VT. This study explored the hypothesis that core translation should influence VT and that a mobile core prosthesis may facilitate physiological motion.
Methods
Vertebral translation (measured with a new method presented here), core translation, range of motion (ROM), and distribution of flexion-extension were measured on flexion-extension, neutral standing, and lateral bending films in 89 patients (63 mobile-core [M]; 33 fixed-core [F]).
Results
At L4-5 levels the VT with M was lower than with F and similar to the VT of untreated levels. At L5-S1 levels the VT with M was lower than with F but was significantly different compared to untreated levels. At M levels a strong correlation was found between VT and core translation; the VT decreases as the core translation increases. At F levels the VT increases as the ROM increases. No significant difference was found between the ROM of untreated levels and levels implanted with either M or F. Regarding the mobility distribution with M and F we observed a deficit in extension at L5-S1 levels and a similar distribution at L4-5 levels compared to untreated levels.
Conclusion
The intervertebral mobility was different between M and F. The M at L4-5 levels succeeded to replicate mobility similar to L4-5 untreated levels. The M at L5-S1 succeeded in ROM, but failed regarding VT and mobility distribution. Nevertheless M minimized VT at L5-S1 levels. The F increased VT at both L4-5 and L5-S1.
Clinical Relevance
This study validates the concept that the core translation of an artificial lumbar disc prosthesis minimizes the VT.
{"title":"Does core mobility of lumbar total disc arthroplasty influence sagittal and frontal intervertebral displacement? Radiologic comparison with fixed-core prosthesis","authors":"Joël Delécrin MD , Jérôme Allain MD , Jacques Beaurain MD , Jean-Paul Steib MD , Hervé Chataigner MD , Lucie Aubourg PhD , Jean Huppert MD , Marc Ameil MD , Jean-Michel Nguyen MD, PhD","doi":"10.1016/j.esas.2009.09.001","DOIUrl":"10.1016/j.esas.2009.09.001","url":null,"abstract":"<div><h3>Background</h3><p>An artificial disc prosthesis is thought to restore segmental motion in the lumbar spine. However, it is reported that disc prosthesis can increase the intervertebral translation (VT). The concept of the mobile-core prosthesis is to mimic the kinematic effects of the migration of the natural nucleus and therefore core mobility should minimize the VT. This study explored the hypothesis that core translation should influence VT and that a mobile core prosthesis may facilitate physiological motion.</p></div><div><h3>Methods</h3><p>Vertebral translation (measured with a new method presented here), core translation, range of motion (ROM), and distribution of flexion-extension were measured on flexion-extension, neutral standing, and lateral bending films in 89 patients (63 mobile-core [M]; 33 fixed-core [F]).</p></div><div><h3>Results</h3><p>At L4-5 levels the VT with M was lower than with F and similar to the VT of untreated levels. At L5-S1 levels the VT with M was lower than with F but was significantly different compared to untreated levels. At M levels a strong correlation was found between VT and core translation; the VT decreases as the core translation increases. At F levels the VT increases as the ROM increases. No significant difference was found between the ROM of untreated levels and levels implanted with either M or F. Regarding the mobility distribution with M and F we observed a deficit in extension at L5-S1 levels and a similar distribution at L4-5 levels compared to untreated levels.</p></div><div><h3>Conclusion</h3><p>The intervertebral mobility was different between M and F. The M at L4-5 levels succeeded to replicate mobility similar to L4-5 untreated levels. The M at L5-S1 succeeded in ROM, but failed regarding VT and mobility distribution. Nevertheless M minimized VT at L5-S1 levels. The F increased VT at both L4-5 and L5-S1.</p></div><div><h3>Clinical Relevance</h3><p>This study validates the concept that the core translation of an artificial lumbar disc prosthesis minimizes the VT.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 91-99"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33155946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-09-01DOI: 10.1016/j.esas.2009.09.006
Timothy Ganey PhD , William Hutton DSc , Hans Jörg Meisel MD, PhD
Successful bone repair is judged in achieving restitution of space and mechanical integrity, and in regaining function. When the biology or anatomy are insufficient to attain a full repair, therapeutic use of graft material has been used to omit compliance features such as strain tolerance, reduced stiffness, and attenuated strength, and instead promote primary or membranous-type bone formation within the physical approximation of a graft material. The challenge of most conductive materials is that they emerge from a static platform and in placement force the living system to adapt to placement, dimension, different properties, and eventually are only successful in degradation and replacement, or in integration. The synergy and interdependency between adhesion, ECM, and proteolysis are important concepts that must be understood to engineer scaffolds capable of holding up to standards which are more than cell decoration. Moreover, the reactive specificity to loading, degradation, therapeutic delivery during absorption remains a key aim of both academic and industrial designs. Achieving conductivity comes with challenges of best fit integration, delivery, and in integrated modeling. The more liquid is the delivery, the more modular the components, and adaptive the matrix to meeting the intended application, the more likely that the conductivity will not be excluded by the morphology of the injury site. Considerations for osteoconductive materials for bone repair and replacement have developed conceptually and advanced parallel with a better understanding of not only bone biology but of materials science. First models of material replacements utilized a reductionist-constructionist logic; define the constituents of the material in terms of its morphology and chemical composition, and then engineer material with similar content and properties as a means of accommodating a replacement. Unfortunately for biologic systems, empiric formulation is insufficient to promote adequate integration in a timely fashion. Future matrices will need to translate their biological surfaces as more than a scaffold to be decorated with cells. Conductivity will be improved by formulations that enhance function, further extended from understanding what composition best suits cell attachment, and be adopted by conveniences of delivery that meet those criteria.
{"title":"Osteoconductive carriers for integrated bone repair","authors":"Timothy Ganey PhD , William Hutton DSc , Hans Jörg Meisel MD, PhD","doi":"10.1016/j.esas.2009.09.006","DOIUrl":"10.1016/j.esas.2009.09.006","url":null,"abstract":"<div><p>Successful bone repair is judged in achieving restitution of space and mechanical integrity, and in regaining function. When the biology or anatomy are insufficient to attain a full repair, therapeutic use of graft material has been used to omit compliance features such as strain tolerance, reduced stiffness, and attenuated strength, and instead promote primary or membranous-type bone formation within the physical approximation of a graft material. The challenge of most conductive materials is that they emerge from a static platform and in placement force the living system to adapt to placement, dimension, different properties, and eventually are only successful in degradation and replacement, or in integration. The synergy and interdependency between adhesion, ECM, and proteolysis are important concepts that must be understood to engineer scaffolds capable of holding up to standards which are more than cell decoration. Moreover, the reactive specificity to loading, degradation, therapeutic delivery during absorption remains a key aim of both academic and industrial designs. Achieving conductivity comes with challenges of best fit integration, delivery, and in integrated modeling. The more liquid is the delivery, the more modular the components, and adaptive the matrix to meeting the intended application, the more likely that the conductivity will not be excluded by the morphology of the injury site. Considerations for osteoconductive materials for bone repair and replacement have developed conceptually and advanced parallel with a better understanding of not only bone biology but of materials science. First models of material replacements utilized a reductionist-constructionist logic; define the constituents of the material in terms of its morphology and chemical composition, and then engineer material with similar content and properties as a means of accommodating a replacement. Unfortunately for biologic systems, empiric formulation is insufficient to promote adequate integration in a timely fashion. Future matrices will need to translate their biological surfaces as more than a scaffold to be decorated with cells. Conductivity will be improved by formulations that enhance function, further extended from understanding what composition best suits cell attachment, and be adopted by conveniences of delivery that meet those criteria.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 108-112"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33155947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-09-01DOI: 10.1016/j.esas.2009.09.007
Jean-Charles Le Huec MD, PhD, Denis Clément PhD, Stéphane Aunoble MD, Clément Tournier MD, Marie Françoise Harmand PhD
{"title":"A brief summary of 15 years of research on beta-tricalcium phosphates","authors":"Jean-Charles Le Huec MD, PhD, Denis Clément PhD, Stéphane Aunoble MD, Clément Tournier MD, Marie Françoise Harmand PhD","doi":"10.1016/j.esas.2009.09.007","DOIUrl":"10.1016/j.esas.2009.09.007","url":null,"abstract":"","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 112-113"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33031253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-09-01DOI: 10.1016/j.esas.2009.09.002
Leonard I. Voronov MD, PhD , Robert M. Havey BS , Simon G. Sjovold MASc , Michael Funk MS , Gerard Carandang BS , Daniel Zindrick BS , David M. Rosler MS , Avinash G. Patwardhan PhD
Background
Total disc replacement (TDR) and total facet replacement (TFR) have been the focus of recent kinematics evaluations. Yet their concurrent function as a total joint replacement of the lumbar spine's 3-joint complex has not been comprehensively reported. This study evaluated the effect of a TFR specifically designed to replace the natural facets and supplement the function with the natural disc and with TDR. The ability to replace degenerated facets to complement a pre-existing or simultaneously implanted TDR may allow surgeons to completely address degenerative pathologies of the 3-joint complex of the lumbar spine. We hypothesized that TFR would reproduce the biomechanical function of the natural facets when implanted in conjunction with TDR.
Methods
Lumbar spines (L1-5, 51.3 ± 14.2 years, N = 6) were tested sequentially as follows: (1) intact, (2) after TDR implantation, and (3) after TFR implantation in conjunction with TDR, all at L3-4. Specimens were tested in flexion-extension (+ 8 Nm to − 6 Nm), lateral bending (± 6 Nm), and axial rotation (± 5 Nm). A 400 N compressive follower preload was applied during flexion-extension tests. Three-dimensional segmental motion was recorded and analyzed using analysis of variance in Systat (Systat Software Inc., Chicago, Illinois) and multiple comparisons with Bonferroni correction.
Results
The TDR implantation (TDR + natural facets) allowed similar lateral bending (P = .66), but it generally increased flexion-extension (P = .06) and axial rotation (P < .05) range of motion (ROM) at the implanted level compared to intact. The TFR + TDR (following replacement of the natural facets with TFR) decreased ROM to levels similar to intact in lateral bending (P = .70) and axial rotation (P = .23). The TFR + TDR flexion-extension ROM was reduced in comparison to intact and TDR + natural facets (P < .05).
Conclusions
The TFR with TDR was able to restore stability to the lumbar segment after bilateral facetectomy, while allowing near-normal motions in all planes.
{"title":"Kinematics of total facet replacement (TFAS-TL) with total disc replacement","authors":"Leonard I. Voronov MD, PhD , Robert M. Havey BS , Simon G. Sjovold MASc , Michael Funk MS , Gerard Carandang BS , Daniel Zindrick BS , David M. Rosler MS , Avinash G. Patwardhan PhD","doi":"10.1016/j.esas.2009.09.002","DOIUrl":"10.1016/j.esas.2009.09.002","url":null,"abstract":"<div><h3>Background</h3><p>Total disc replacement (TDR) and total facet replacement (TFR) have been the focus of recent kinematics evaluations. Yet their concurrent function as a total joint replacement of the lumbar spine's 3-joint complex has not been comprehensively reported. This study evaluated the effect of a TFR specifically designed to replace the natural facets and supplement the function with the natural disc and with TDR. The ability to replace degenerated facets to complement a pre-existing or simultaneously implanted TDR may allow surgeons to completely address degenerative pathologies of the 3-joint complex of the lumbar spine. We hypothesized that TFR would reproduce the biomechanical function of the natural facets when implanted in conjunction with TDR.</p></div><div><h3>Methods</h3><p>Lumbar spines (L1-5, 51.3 ± 14.2 years, N = 6) were tested sequentially as follows: (1) intact, (2) after TDR implantation, and (3) after TFR implantation in conjunction with TDR, all at L3-4. Specimens were tested in flexion-extension (+ 8 Nm to − 6 Nm), lateral bending (± 6 Nm), and axial rotation (± 5 Nm). A 400 N compressive follower preload was applied during flexion-extension tests. Three-dimensional segmental motion was recorded and analyzed using analysis of variance in Systat (Systat Software Inc., Chicago, Illinois) and multiple comparisons with Bonferroni correction.</p></div><div><h3>Results</h3><p>The TDR implantation (TDR + natural facets) allowed similar lateral bending (<em>P</em> = .66), but it generally increased flexion-extension (<em>P</em> = .06) and axial rotation (<em>P</em> < .05) range of motion (ROM) at the implanted level compared to intact. The TFR + TDR (following replacement of the natural facets with TFR) decreased ROM to levels similar to intact in lateral bending (<em>P</em> = .70) and axial rotation (<em>P</em> = .23). The TFR + TDR flexion-extension ROM was reduced in comparison to intact and TDR + natural facets (<em>P</em> < .05).</p></div><div><h3>Conclusions</h3><p>The TFR with TDR was able to restore stability to the lumbar segment after bilateral facetectomy, while allowing near-normal motions in all planes.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 3","pages":"Pages 85-90"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.esas.2009.09.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33154948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-06-01DOI: 10.1016/S1935-9810(09)70006-4
Aliza A. Allon MS , Richard A. Schneider Ph.D , Jeffrey C. Lotz Ph.D
Background
Our goal is to optimize stem cell-based tissue engineering strategies in the context of the intervertebral disc environment. We explored the benefits of co-culturing nucleus pulposus cells (NPC) and adult mesenchymal stem cells (MSC) using a novel spherical bilaminar pellet culture system where one cell type is enclosed in a sphere of the other cell type. Our 3D system provides a structure that exploits embryonic processes such as tissue induction and condensation. We observed a unique phenomenon: the budding of co-culture pellets and the formation of satellite pellets that separate from the main pellet.
Methods
MSC and NPC co-culture pellets were formed with three different structural organizations. The first had random organization. The other two had bilaminar organization with either MSC inside and NPC outside or NPC inside and MSC outside.
Results
By 14 days, all co-culture pellets exhibited budding and spontaneously generated satellite pellets. The satellite pellets were composed of both cell types and, surprisingly, all had the same bilaminar organization with MSC on the inside and NPC on the outside. This organization was independent of the structure of the main pellet that the satellites stemmed from.
Conclusion
The main pellets generated satellite pellets that spontaneously organized into a bilaminar structure. This implies that structural organization occurs naturally in this cell culture system and may be inherently favorable for cell-based tissue engineering strategies. The occurrence of budding and the organization of satellite pellets may have important implications for the use of co-culture pellets in cell-based therapies for disc regeneration.
Clinical Relevance
From a therapeutic point of view, the generation of satellite pellets may be a beneficial feature that would serve to spread donor cells throughout the host matrix and restore normal matrix composition in a sustainable way, ultimately renewing tissue function.
{"title":"Co-culture of Adult Mesenchymal Stem Cells and Nucleus Pulposus Cells in Bilaminar Pellets for Intervertebral Disc Regeneration","authors":"Aliza A. Allon MS , Richard A. Schneider Ph.D , Jeffrey C. Lotz Ph.D","doi":"10.1016/S1935-9810(09)70006-4","DOIUrl":"https://doi.org/10.1016/S1935-9810(09)70006-4","url":null,"abstract":"<div><h3>Background</h3><p>Our goal is to optimize stem cell-based tissue engineering strategies in the context of the intervertebral disc environment. We explored the benefits of co-culturing nucleus pulposus cells (NPC) and adult mesenchymal stem cells (MSC) using a novel spherical bilaminar pellet culture system where one cell type is enclosed in a sphere of the other cell type. Our 3D system provides a structure that exploits embryonic processes such as tissue induction and condensation. We observed a unique phenomenon: the budding of co-culture pellets and the formation of satellite pellets that separate from the main pellet.</p></div><div><h3>Methods</h3><p>MSC and NPC co-culture pellets were formed with three different structural organizations. The first had random organization. The other two had bilaminar organization with either MSC inside and NPC outside or NPC inside and MSC outside.</p></div><div><h3>Results</h3><p>By 14 days, all co-culture pellets exhibited budding and spontaneously generated satellite pellets. The satellite pellets were composed of both cell types and, surprisingly, all had the same bilaminar organization with MSC on the inside and NPC on the outside. This organization was independent of the structure of the main pellet that the satellites stemmed from.</p></div><div><h3>Conclusion</h3><p>The main pellets generated satellite pellets that spontaneously organized into a bilaminar structure. This implies that structural organization occurs naturally in this cell culture system and may be inherently favorable for cell-based tissue engineering strategies. The occurrence of budding and the organization of satellite pellets may have important implications for the use of co-culture pellets in cell-based therapies for disc regeneration.</p></div><div><h3>Clinical Relevance</h3><p>From a therapeutic point of view, the generation of satellite pellets may be a beneficial feature that would serve to spread donor cells throughout the host matrix and restore normal matrix composition in a sustainable way, ultimately renewing tissue function.</p></div>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 2","pages":"Pages 41-49"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1935-9810(09)70006-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137345078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-06-01DOI: 10.1016/S1935-9810(09)70007-6
Leonard I. Voronov MD, PhD , Robert M. Havey BS , David M. Rosler MS , Simon G. Sjovold MASc , Susan L. Rogers MS , Gerard Carandang BS , Jorge A. Ochoa PhD , Hansen Yuan MD , Scott Webb DO , Avinash G. Patwardhan PhD
Background
Facet arthroplasty is a motion restoring procedure. It is normally suggested as an alternative to rigid fixation after destabilizing decompression procedures in the posterior lumbar spine. While previous studies have reported successful results in reproducing normal spine kinematics after facet replacement at L4-5 and L3-4, there are no data on the viability of facet replacement at the lumbosacral joint. The anatomy of posterior elements and the resulting kinematics at L5-S1 are distinctly different from those at superior levels, making the task of facet replacement at the lumbosacral level challenging. This study evaluated the kinematics of facet replacement at L5-S1.
Methods
Six human cadaveric lumbar spines (L1-S1, 46.7 ± 13.0 years) were tested in the following sequence: (1) intact (L1-S1), (2) complete laminectomy and bilateral facetectomy at L5-S1, and (3) implantation of TFAS-LS (Lumbosacral Total Facet Arthroplasty System, Archus Orthopedics, Redmond, Washington) at L5-S1 using pedicle screws. Specimens were tested in flexion (8Nm), extension (6Nm), lateral bending (LB, ± 6Nm), and axial rotation (AR, ± 5Nm). The level of significance was α = .017 after Bonferroni correction for three comparisons: (1) intact vs. destabilized, (2) destabilized vs. reconstructed, and (3) intact vs. reconstructed.
Results
Laminectomy-facetectomy at L5-S1 increased the L5-S1 angular range of motion (ROM) in all directions. Flexion-extension (F-E) ROM increased from 15.3 ± 2.9 to 18.7 ± 3.5 degrees (P < .017), LB from 8.2 ± 1.8 to 9.3 ± 1.6 degrees (P < .017), and AR from 3.7 ± 2.0 to 5.9 ± 1.8 degrees (P < .017). The facet arthroplasty system decreased ROM compared to the laminectomy-facetectomy condition in all tested directions (P < .017). The facet arthroplasty system restored the L5-S1 ROM to its intact levels in LB and AR (P > .017). F-E ROM after the facet arthroplasty system implantation was smaller than the intact value (10.1 ± 2.2 vs. 15.3 ± 2.9 degrees, P < .017). The load-displacement curves after the facet arthroplasty system implantation at L5-S1 were sigmoidal, and quality of motion measures were similar to intact, demonstrating graded resistance to angular motion in F-E, LB and AR.
Conclusions
The facet arthroplasty system was able to restore stability to the lumbosacral segment after complete laminectomy and bilateral facetectomy, while also allowing near-normal kinematics in all planes. While F-E ROM after the facet arthroplasty system implantation
{"title":"L5 – S1 Segmental Kinematics After Facet Arthroplasty","authors":"Leonard I. Voronov MD, PhD , Robert M. Havey BS , David M. Rosler MS , Simon G. Sjovold MASc , Susan L. Rogers MS , Gerard Carandang BS , Jorge A. Ochoa PhD , Hansen Yuan MD , Scott Webb DO , Avinash G. Patwardhan PhD","doi":"10.1016/S1935-9810(09)70007-6","DOIUrl":"https://doi.org/10.1016/S1935-9810(09)70007-6","url":null,"abstract":"<div><h3>Background</h3><p>Facet arthroplasty is a motion restoring procedure. It is normally suggested as an alternative to rigid fixation after destabilizing decompression procedures in the posterior lumbar spine. While previous studies have reported successful results in reproducing normal spine kinematics after facet replacement at L4-5 and L3-4, there are no data on the viability of facet replacement at the lumbosacral joint. The anatomy of posterior elements and the resulting kinematics at L5-S1 are distinctly different from those at superior levels, making the task of facet replacement at the lumbosacral level challenging. This study evaluated the kinematics of facet replacement at L5-S1.</p></div><div><h3>Methods</h3><p>Six human cadaveric lumbar spines (L1-S1, 46.7<!--> <!-->±<!--> <!-->13.0 years) were tested in the following sequence: (1) intact (L1-S1), (2) complete laminectomy and bilateral facetectomy at L5-S1, and (3) implantation of TFAS-LS (Lumbosacral Total Facet Arthroplasty System, Archus Orthopedics, Redmond, Washington) at L5-S1 using pedicle screws. Specimens were tested in flexion (8Nm), extension (6Nm), lateral bending (LB,<!--> <!-->±<!--> <!-->6Nm), and axial rotation (AR,<!--> <!-->±<!--> <!-->5Nm). The level of significance was α<!--> <!-->=<!--> <!-->.017 after Bonferroni correction for three comparisons: (1) intact vs. destabilized, (2) destabilized vs. reconstructed, and (3) intact vs. reconstructed.</p></div><div><h3>Results</h3><p>Laminectomy-facetectomy at L5-S1 increased the L5-S1 angular range of motion (ROM) in all directions. Flexion-extension (F-E) ROM increased from 15.3<!--> <!-->±<!--> <!-->2.9 to 18.7<!--> <!-->±<!--> <!-->3.5 degrees (<em>P</em> <!--><<!--> <!-->.017), LB from 8.2<!--> <!-->±<!--> <!-->1.8 to 9.3<!--> <!-->±<!--> <!-->1.6 degrees (<em>P</em> <!--><<!--> <!-->.017), and AR from 3.7<!--> <!-->±<!--> <!-->2.0 to 5.9<!--> <!-->±<!--> <!-->1.8 degrees (<em>P</em> <!--><<!--> <!-->.017). The facet arthroplasty system decreased ROM compared to the laminectomy-facetectomy condition in all tested directions (<em>P</em> <!--><<!--> <!-->.017). The facet arthroplasty system restored the L5-S1 ROM to its intact levels in LB and AR (<em>P</em> <!-->><!--> <!-->.017). F-E ROM after the facet arthroplasty system implantation was smaller than the intact value (10.1<!--> <!-->±<!--> <!-->2.2 vs. 15.3<!--> <!-->±<!--> <!-->2.9 degrees, <em>P</em> <!--><<!--> <!-->.017). The load-displacement curves after the facet arthroplasty system implantation at L5-S1 were sigmoidal, and quality of motion measures were similar to intact, demonstrating graded resistance to angular motion in F-E, LB and AR.</p></div><div><h3>Conclusions</h3><p>The facet arthroplasty system was able to restore stability to the lumbosacral segment after complete laminectomy and bilateral facetectomy, while also allowing near-normal kinematics in all planes. While F-E ROM after the facet arthroplasty system implantation","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 2","pages":"Pages 50-58"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1935-9810(09)70007-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137345079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-06-01eCollection Date: 2009-01-01DOI: 10.1016/SASJ-2008-0027-RR
Thomas J Errico, Jonathan R Kamerlink, Martin Quirno, Jacques Samani, Robert J Chomiak
Background: The purpose of this study was to determine the indications for implantation of the coflex device (Paradigm Spine, LLC, New York, New York), assess long-term complications, and evaluate the long-term clinical outcomes of patients.
Methods: A total of 127 patients underwent placement of a coflex implant for various indications by one orthopaedic spine surgeon. The mean follow-up was 6.3 years. The original indications for implantation were determined based upon the data provided in the case report forms. Preoperatively and postoperatively, patients were asked to grade their low-back and leg pain using the visual analog scale (VAS) and the pain severity scale: no pain (0), mild pain (1), moderate pain (2), or severe pain (3). Patients were queried about their satisfaction with the surgical procedure. Follow-up radiographs were taken to determine any device-related issues.
Results: The most prevalent diagnoses for implantation were spinal stenosis (19.7%) and spinal stenosis with lumbar disc herniation (35.4%). The mean severity of low-back pain was decreased by 33% (from moderate to mild) at the 2-year follow-up (P < .001) and at the 5-year follow-up (from moderate to mild, P < .001). The mean severity of leg pain was decreased by 66% (from severe to mild) at the 2-year follow-up (P < .001) and at the 5-year follow-up (from severe to mild, P < .001). At the mean follow-up period of 6.3 years, a patient satisfaction query demonstrated that 7% were unsatisfied, 46% were satisfied, and 46% were very satisfied with their clinical outcome. Based on the follow-up radiographs, 92 of patients had no devicerelated issues and 8% had device-related issues.
Conclusion: The data provided have demonstrated that the coflex implant provides pain relief for patients with low-back pain and leg pain. The most common indications for implantation were spinal stenosis and spinal stenosis with lumbar disc herniation. There were very few device-related complications.
Clinical significance: Using coflex is a safe and viable option in the selection of instrumentation for spinal stabilization.
背景:本研究的目的是确定coflex装置植入的适应症(Paradigm Spine, LLC, New York, New York),评估长期并发症,并评估患者的长期临床结果。方法:共有127例患者接受了一个骨科脊柱外科医生的各种适应症的coflex植入。平均随访时间为6.3年。最初的植入适应症是根据病例报告表格中提供的数据确定的。术前和术后,患者被要求使用视觉模拟量表(VAS)和疼痛严重程度量表对腰背痛和腿部疼痛进行分级:无疼痛(0)、轻度疼痛(1)、中度疼痛(2)或重度疼痛(3)。询问患者对手术过程的满意度。随访x线片以确定任何与器械相关的问题。结果:椎管狭窄症(19.7%)和椎管狭窄症合并腰椎间盘突出症(35.4%)是植入术中最常见的诊断。2年随访时腰痛的平均严重程度(从中度到轻度)降低了33% (P < 0.001), 5年随访时(从中度到轻度,P < 0.001)。在2年随访期间(从严重到轻微)和5年随访期间(从严重到轻微,P < 0.001),腿部疼痛的平均严重程度降低了66%。在平均6.3年的随访期间,患者满意度查询显示,7%的患者不满意,46%的患者满意,46%的患者非常满意他们的临床结果。根据随访x线片,92例患者无器械相关问题,8%有器械相关问题。结论:所提供的数据表明,coflex植入物可以缓解腰痛和腿痛患者的疼痛。最常见的适应症是椎管狭窄和椎管狭窄合并腰椎间盘突出。很少有器械相关的并发症。临床意义:使用coflex固定是一种安全可行的选择。
{"title":"Survivorship of coflex Interlaminar-Interspinous Implant.","authors":"Thomas J Errico, Jonathan R Kamerlink, Martin Quirno, Jacques Samani, Robert J Chomiak","doi":"10.1016/SASJ-2008-0027-RR","DOIUrl":"https://doi.org/10.1016/SASJ-2008-0027-RR","url":null,"abstract":"<p><strong>Background: </strong>The purpose of this study was to determine the indications for implantation of the coflex device (Paradigm Spine, LLC, New York, New York), assess long-term complications, and evaluate the long-term clinical outcomes of patients.</p><p><strong>Methods: </strong>A total of 127 patients underwent placement of a coflex implant for various indications by one orthopaedic spine surgeon. The mean follow-up was 6.3 years. The original indications for implantation were determined based upon the data provided in the case report forms. Preoperatively and postoperatively, patients were asked to grade their low-back and leg pain using the visual analog scale (VAS) and the pain severity scale: no pain (0), mild pain (1), moderate pain (2), or severe pain (3). Patients were queried about their satisfaction with the surgical procedure. Follow-up radiographs were taken to determine any device-related issues.</p><p><strong>Results: </strong>The most prevalent diagnoses for implantation were spinal stenosis (19.7%) and spinal stenosis with lumbar disc herniation (35.4%). The mean severity of low-back pain was decreased by 33% (from moderate to mild) at the 2-year follow-up (P < .001) and at the 5-year follow-up (from moderate to mild, P < .001). The mean severity of leg pain was decreased by 66% (from severe to mild) at the 2-year follow-up (P < .001) and at the 5-year follow-up (from severe to mild, P < .001). At the mean follow-up period of 6.3 years, a patient satisfaction query demonstrated that 7% were unsatisfied, 46% were satisfied, and 46% were very satisfied with their clinical outcome. Based on the follow-up radiographs, 92 of patients had no devicerelated issues and 8% had device-related issues.</p><p><strong>Conclusion: </strong>The data provided have demonstrated that the coflex implant provides pain relief for patients with low-back pain and leg pain. The most common indications for implantation were spinal stenosis and spinal stenosis with lumbar disc herniation. There were very few device-related complications.</p><p><strong>Clinical significance: </strong>Using coflex is a safe and viable option in the selection of instrumentation for spinal stabilization.</p>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 2","pages":"59-67"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/0e/9b/SAS-3-2008-0027-RR.PMC4365593.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33154946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-06-01eCollection Date: 2009-01-01DOI: 10.1016/SASJ-2009-0001-RR
Leonard I Voronov, Robert M Havey, David M Rosler, Simon G Sjovold, Susan L Rogers, Gerard Carandang, Jorge A Ochoa, Hansen Yuan, Scott Webb, Avinash G Patwardhan
Background: Facet arthroplasty is a motion restoring procedure. It is normally suggested as an alternative to rigid fixation after destabilizing decompression procedures in the posterior lumbar spine. While previous studies have reported successful results in reproducing normal spine kinematics after facet replacement at L4-5 and L3-4, there are no data on the viability of facet replacement at the lumbosacral joint. The anatomy of posterior elements and the resulting kinematics at L5-S1 are distinctly different from those at superior levels, making the task of facet replacement at the lumbosacral level challenging. This study evaluated the kinematics of facet replacement at L5-S1.
Methods: Six human cadaveric lumbar spines (L1-S1, 46.7 ± 13.0 years) were tested in the following sequence: (1) intact (L1-S1), (2) complete laminectomy and bilateral facetectomy at L5-S1, and (3) implantation of TFAS-LS (Lumbosacral Total Facet Arthroplasty System, Archus Orthopedics, Redmond, Washington) at L5-S1 using pedicle screws. Specimens were tested in flexion (8Nm), extension (6Nm), lateral bending (LB, ± 6Nm), and axial rotation (AR, ± 5Nm). The level of significance was α = .017 after Bonferroni correction for three comparisons: (1) intact vs. destabilized, (2) destabilized vs. reconstructed, and (3) intact vs. reconstructed.
Results: Laminectomy-facetectomy at L5-S1 increased the L5-S1 angular range of motion (ROM) in all directions. Flexion-extension (F-E) ROM increased from 15.3 ± 2.9 to 18.7 ± 3.5 degrees (P < .017), LB from 8.2 ± 1.8 to 9.3 ± 1.6 degrees (P < .017), and AR from 3.7 ± 2.0 to 5.9 ± 1.8 degrees (P < .017). The facet arthroplasty system decreased ROM compared to the laminectomy-facetectomy condition in all tested directions (P < .017). The facet arthroplasty system restored the L5-S1 ROM to its intact levels in LB and AR (P > .017). F-E ROM after the facet arthroplasty system implantation was smaller than the intact value (10.1 ± 2.2 vs. 15.3 ± 2.9 degrees, P < .017). The load-displacement curves after the facet arthroplasty system implantation at L5-S1 were sigmoidal, and quality of motion measures were similar to intact, demonstrating graded resistance to angular motion in F-E, LB and AR.
Conclusions: The facet arthroplasty system was able to restore stability to the lumbosacral segment after complete laminectomy and bilateral facetectomy, while also allowing near-normal kinematics in all planes. While F-E ROM after the facet arthroplasty system implantation was smaller than the intact value, it was within the physiologic norms for L5-S1. These results are consistent with previous studies of facet arthroplasty at L3-L4 and L4-L5 and demonstrate that TFAS technology can be adapted to the lumbosacral joint with functionality comparable to its application in superior lumbar levels.
{"title":"L5 - s1 segmental kinematics after facet arthroplasty.","authors":"Leonard I Voronov, Robert M Havey, David M Rosler, Simon G Sjovold, Susan L Rogers, Gerard Carandang, Jorge A Ochoa, Hansen Yuan, Scott Webb, Avinash G Patwardhan","doi":"10.1016/SASJ-2009-0001-RR","DOIUrl":"https://doi.org/10.1016/SASJ-2009-0001-RR","url":null,"abstract":"<p><strong>Background: </strong>Facet arthroplasty is a motion restoring procedure. It is normally suggested as an alternative to rigid fixation after destabilizing decompression procedures in the posterior lumbar spine. While previous studies have reported successful results in reproducing normal spine kinematics after facet replacement at L4-5 and L3-4, there are no data on the viability of facet replacement at the lumbosacral joint. The anatomy of posterior elements and the resulting kinematics at L5-S1 are distinctly different from those at superior levels, making the task of facet replacement at the lumbosacral level challenging. This study evaluated the kinematics of facet replacement at L5-S1.</p><p><strong>Methods: </strong>Six human cadaveric lumbar spines (L1-S1, 46.7 ± 13.0 years) were tested in the following sequence: (1) intact (L1-S1), (2) complete laminectomy and bilateral facetectomy at L5-S1, and (3) implantation of TFAS-LS (Lumbosacral Total Facet Arthroplasty System, Archus Orthopedics, Redmond, Washington) at L5-S1 using pedicle screws. Specimens were tested in flexion (8Nm), extension (6Nm), lateral bending (LB, ± 6Nm), and axial rotation (AR, ± 5Nm). The level of significance was α = .017 after Bonferroni correction for three comparisons: (1) intact vs. destabilized, (2) destabilized vs. reconstructed, and (3) intact vs. reconstructed.</p><p><strong>Results: </strong>Laminectomy-facetectomy at L5-S1 increased the L5-S1 angular range of motion (ROM) in all directions. Flexion-extension (F-E) ROM increased from 15.3 ± 2.9 to 18.7 ± 3.5 degrees (P < .017), LB from 8.2 ± 1.8 to 9.3 ± 1.6 degrees (P < .017), and AR from 3.7 ± 2.0 to 5.9 ± 1.8 degrees (P < .017). The facet arthroplasty system decreased ROM compared to the laminectomy-facetectomy condition in all tested directions (P < .017). The facet arthroplasty system restored the L5-S1 ROM to its intact levels in LB and AR (P > .017). F-E ROM after the facet arthroplasty system implantation was smaller than the intact value (10.1 ± 2.2 vs. 15.3 ± 2.9 degrees, P < .017). The load-displacement curves after the facet arthroplasty system implantation at L5-S1 were sigmoidal, and quality of motion measures were similar to intact, demonstrating graded resistance to angular motion in F-E, LB and AR.</p><p><strong>Conclusions: </strong>The facet arthroplasty system was able to restore stability to the lumbosacral segment after complete laminectomy and bilateral facetectomy, while also allowing near-normal kinematics in all planes. While F-E ROM after the facet arthroplasty system implantation was smaller than the intact value, it was within the physiologic norms for L5-S1. These results are consistent with previous studies of facet arthroplasty at L3-L4 and L4-L5 and demonstrate that TFAS technology can be adapted to the lumbosacral joint with functionality comparable to its application in superior lumbar levels.</p>","PeriodicalId":88695,"journal":{"name":"SAS journal","volume":"3 2","pages":"50-8"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/9c/1a/SAS-3-2009-0001-RR.PMC4365591.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33154945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}