Radiographic and safety details of vertebral body stenting : results from a multicenter chart review

Background: Up to one third of BKP treated cases shows no appreciable height restoration due to loss of both restored height and kyphotic realignment after balloon deflation. This shortcoming has called for an improved method that maintains the height and realignment reached by the fully inflated balloon until stabilization of the vertebral body by PMMA-based cementation. Restoration of the physiological vertebral body height for pain relief and for preventing further fractures of adjacent and distant vertebral bodies must be the main aim for such a method. A new vertebral body stenting system (VBS) stabilizes the vertebral body after balloon deflation until cementation. The radiographic and safety results of the first 100 cases where VBS was applied are presented. Methods: During the planning phase of an ongoing international multicenter RCT, radiographic, procedural and followup details were retrospectively transcribed from charts and xrays for developing and testing the case report forms. Radiographs were centrally assessed at the institution of the first/senior author. Results: 100 patients (62 with osteoporosis) with a total of 103 fractured vertebral bodies were treated with the VBS system. 49 were females with a mean age of 73.2 years; males were 66.7 years old. The mean preoperative anterior-middle-posterior heights were 20.3-17.6-28.0 mm, respectively. The mean local kyphotic angle was 13.1°. The mean preoperative Beck Index (anterior edge height/posterior edge height) was 0.73, the mean alternative Beck Index (middle height/posterior edge height) was 0.63. The mean postoperative heights were restored to 24.5-24.6-30.4 mm, respectively. The mean local kyphotic angle was reduced to 8.9°. The mean postoperative Beck Index was 0.81, the mean alternative one was 0.82. The overall extrusion rate was 29.1%, the symptomatic one was 1%. In the osteoporosis subgroup there were 23.8% extrusions. Within the three months followup interval there were 9% of adjacent and 4% of remote new fractures, all in the osteoporotic group. Conclusions: VBS showed its strengths especially in realignment of crush and biconcave fractures. Given that fracture mobility is present, the realignment potential is sound and increases with the severity of preoperative vertebral body deformation

PMMA-Cement-PLIF Is Safe and Effective as a Single-Stage Posterior Procedure in Treating Pyogenic Erosive Lumbar Spondylodiscitis-A Single-Center Retrospective Study of 73 Cases.

BACKGROUND Surgical treatment for erosive pyogenic spondylodiscitis of the lumbar spine is challenging as, following debridement of the intervertebral and bony abscess, a large and irregular defect is created. Sufficient defect reconstruction with conventional implants using a posterior approach is often impossible. Therefore, we developed the "Cement-PLIF", a single-stage posterior lumbar procedure, combining posterior lumbar interbody fusion (PLIF) with defect-filling using antibiotic-loaded polymethylmethacrylate (PMMA). This study first describes and evaluates the procedure's efficacy, safety, and infection eradication rate. Radiological implant stability, bone-regeneration, sagittal profile reconstruction, procedure-related complications, and pre-existing comorbidities were further analyzed. METHODS A retrospective cohort study analyzing 73 consecutive patients with a minimum of a one-year follow-up from 2000-2017. Patient-reported pain levels and improvement in infectious serological parameters evaluated the clinical outcome. Sagittal profile reconstruction, anterior bone-regeneration, and posterior fusion were analyzed in a.p. and lateral radiographs. A Kaplan-Meier analysis was used to determine the impact of pre-existing comorbidities on mortality. Pre-existing comorbidities were quantified using the Charlson-Comorbidity Index (CCI). RESULTS Mean follow-up was 3.3 (range: 1-16; ±3.2) years. There was no evidence of infection persistence in all patients at the one-year follow-up. One patient underwent revision surgery for early local infection recurrence (1.4%). Five (6.9%) patients required an early secondary intervention at the same level due to minor complications. Radiological follow-up revealed implant stability in 70/73 (95.9%) cases. Successful sagittal reconstruction was demonstrated in all patients (p < 0.001). There was a significant correlation between Kaplan-Meier survival and the number of pre-existing comorbidities (24-months-survival: CCI ≤ 3: 100%; CCI ≥ 3: 84.6%; p = 0.005). CONCLUSIONS The Cement-PLIF procedure for pyogenic erosive spondylodiscitis is an effective and safe treatment as evaluated by infection elimination, clinical outcome, restoration, and maintenance of stability and sagittal alignment

Spheroid-like Cultures for Cell Expansion of Angiopoietin Receptor-1 (aka. Tie2) positive Cells from the human Intervertebral Disc

INTRODUCTION:Low back pain is the leading cause of disability worldwide (1). Nevertheless, the mechanism of the intervertebral disc (IVD) degeneration is still not clear. In this context, the nucleus pulposus (NP) and more precisely NP progenitor cells (NPPCs) present in the IVD, positive for angiopoietin-1 receptor (aka. Tie2) display multipotent and stem capacity (2,3). In this study, the first aim was to determine whether spheroid formation in suspension-culture will increase the amount/percentage of NPPCs during the expansion compared to traditional monolayer culture. The second aim of this study was to investigate if the percentage of NPPCs will be enriched even further by the resuspension of the spheroid-like cultured cells (=1st generation) and reformation of those spheroids one more time (= 2nd generation). METHODS:Human NP tissues from trauma patients (N=3) were obtained with written ethical consent and isolated by a two-step digestion protocol (3). The NP cells were resuspended and frozen at -150°C after reaching confluence of passage 0. At passage 1, NP cells were seeded in standard or ultra-low attachment tissue culture flasks with 2.5 ng/ml FGF-2 in low glucose - DMEM (supplemented with 10 % FBS). Flow cytometry was used to analyze and quantify the percentage of NPPCs using Tie2 antibody. We defined the spheroids formed after passage 1 NPCs as 1st generation spheroid. We obtained the 2nd generation spheroids by resuspending the 1st-generation-spheroid and reassembly. The NPCs from 1st and 2nd spheroid were quantified by CFU-assay. RESULTS:As a result, the percentage of NPPCs in monolayer culture condition was reaching 7 ± 2 % (Mean±SEM), however, in the 1st and 2nd generation spheroids culture condition, we were observing 20 ± 10 % and 28 ± 6% of Tie2+ cells, respectively. Concerning the CFU-assay, the NPCs from the 2nd generation spheroid formed 30 CFU-S per 1,000 cells, which were twice more CFU-S compared to the 1st generation spheroid. DISCUSSION & CONCLUSIONS:From these data we conclude than the spheroid-like formation of NPCs would be a more efficient method for expansion and enrichment of NPPCs than monolayer expansion in a context of future cell therapy. Acknowledgements:Financial support was received from iPSpine H2020 project under grant agreement #825925 and China Scholarship Council to X.Z

Mimicking the Intervertebral Disc Microenvironment for Expansion of Nucleus Pulposus Progenitor Cells in a Context of Cell Therapy

INTRODUCTION: Low back pain (LBP) is a global health concern that affects as many as 75–80% of people during their lifetime. Although the causes of LBP are multifactorial, increasing evidence implicates intervertebral disc (IVD) degeneration as a major contributor. In this respect, tissue-specific progenitors may play a crucial role in tissue regeneration, as these cells are perfectly adapted to their niche. Recently, the progenitor cell population was described in the nucleus pulposus (NP) of the IVD. These cells, positive for the Tie2 marker, have self-renewal capacity and in vitro multipotency potential. However, extremely low numbers of the NP progenitors limit the feasibility of cell therapy strategies. Here, we study the influence of the culture method and of the microenvironment on the human NP progenitors and their differentiation potential in vitro. METHODS:Cells were obtained from human NP tissue from trauma patients undergoing spinal surgery. Briefly, after mild overnight digestion, the NP tissue cells were cultured in 2D (monolayer) or 3D (alginate beads) conditions with medium supplemented in ascorbic acid. After 2 weeks, cells from 2D or 3D culture were expanded on fibronectin-coating flasks with medium supplemented in FGF-2 to mimic the native microenvironment of NP cells. Subsequently, expanded NP cells were then characterized by cytometry (CD105, CD90, CD73, CD45, CD34, and Tie2) and tri-lineage differentiation, which was analyzed by qPCR and histology. RESULTS: Cytometry analysis, after 2D- or 3D-expansion showed the presence of 0.1 % and 78.2 % of Tie2+ NP progenitors, respectively. Concerning the chondrogenic differentiation assay, the detection of glycosaminoglycans in the culture medium was drastically increased for 3D-expanded cells (11-fold) vs 2D-expanded cells. Moreover, the relative gene expression of collagen type 2 and aggrecan was also increased (600-fold and 2-fold, respectively). Regarding osteogenic differentiation assay, relative gene expression for osteopontin increased for 3D- (150-fold) vs 2D-expanded cells. However, no difference was observed between 2D and 3D expansion for the adipogenic differentiation assay. DISCUSSION & CONCLUSIONS: The present study shows that 3D expansion of NP cells better preserves the progenitor's cells population and increases the chondrogenic and osteogenic differentiation potential compared to 2D expansion. This project not only has a scientific impact by evaluating the role of native physiological niches on the functionality of NP progenitors but could also lead to an innovative clinical approach with cell therapy for IVD regeneration and repair. Acknowledgments: Financial support was received from iPSpine H2020 project #825925

Regional and experiential differences in surgeon preference for the treatment of cervical facet injuries: a case study survey with the AO Spine Cervical Classification Validation Group

PURPOSE: The management of cervical facet dislocation injuries remains controversial. The main purpose of this investigation was to identify whether a surgeon\u27s geographic location or years in practice influences their preferred management of traumatic cervical facet dislocation injuries. METHODS: A survey was sent to 272 AO Spine members across all geographic regions and with a variety of practice experience. The survey included clinical case scenarios of cervical facet dislocation injuries and asked responders to select preferences among various diagnostic and management options. RESULTS: A total of 189 complete responses were received. Over 50% of responding surgeons in each region elected to initiate management of cervical facet dislocation injuries with an MRI, with 6 case exceptions. Overall, there was considerable agreement between American and European responders regarding management of these injuries, with only 3 cases exhibiting a significant difference. Additionally, results also exhibited considerable management agreement between those with ≤ 10 and \u3e 10 years of practice experience, with only 2 case exceptions noted. CONCLUSION: More than half of responders, regardless of geographical location or practice experience, identified MRI as a screening imaging modality when managing cervical facet dislocation injuries, regardless of the status of the spinal cord and prior to any additional intervention. Additionally, a majority of surgeons would elect an anterior approach for the surgical management of these injuries. The study found overall agreement in management preferences of cervical facet dislocation injuries around the globe

Percutaneous cement augmentation techniques for osteoporotic spinal fractures

Minimally invasive vertebral augmentation-based techniques have been used for the treatment of spinal fractures (osteoporotic and malignant) for approximately 25 years. In this review, we try to give an overview of the current spectrum of percutaneous augmentation techniques, safety aspects and indications. Crucial factors for success are careful patient selection, proper technique and choice of the ideal cement augmentation option. Most compression fractures present a favourable natural course, with reduction of pain and regainment of mobility after a few days to several weeks, whereas other patients experience a progressive collapse and persisting pain. In this situation, percutaneous cement augmentation is an effective treatment option with regards to pain and disability reduction, improvement of quality of life and ambulatory and pulmonary function