bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chondrosarcomas of the Spine: Prognostic Variables for Local Recurrence and Mortality in a Multicenter Study
Authors: Versteeg Anne , Fisher Charles , Boriani Stefano , Varga Peter , Dekutoski Mark , Luzatti Alessandro , Gokaslan Ziya , Williams Richard , Reynolds Jeremy , Fehlings Michael , Bettegowda Chetan , Rhines Laurence 
Published: May 2015

Introduction Primary spinal chondrosarcomas are rare. Best available evidence consists of small case series, making it difficult to determine optimal management and risk factors for local recurrence and mortality. The application of the Enneking classification in the treatment of primary bone tumors in the appendicular skeleton has led to a longer life expectancy, yet the application of the Enneking system in the treatment of primary bone tumors in the spine has not been widely accepted. Therefore, the aim of this multicenter cohort study was to determine prognostic variables, including application of the Enneking classification, for local recurrence and mortality following surgical intervention for spinal chondrosarcomas. Patients and Methods AOSpine knowledge forum tumor developed a multicenter ambispective database of surgically treated patients with spinal chondrosarcoma. Patient data pertaining to demographics, diagnosis, treatment, cross-sectional survival, and local recurrence were collected. Tumors were classified according to the Enneking classification. Patients were analyzed in the following two different cohorts; Enneking appropriate (EA) and Enneking inappropriate (EI). EA was defined by the final pathology margin matching the Enneking recommended surgical margin and EI by not matching. Results Between 1987 and 2011, 112 patients (mean age at surgery = 47 ± 16 years) underwent surgical treatment for a primary spinal chondrosarcoma. EA surgery was performed in 61 (58%) patients. Overall, 15 patients (25%) suffered a local recurrence in the EA group and 21 (48%) in the EI group. EI approach significantly increased the risk for local recurrence ( p = 0.009). Overall, 38 (34%) patients died during the study period (mean follow-up = 3.6 ± 3.2 years); factors associated with increased overall survival were absence of adjuvant therapy ( p = 0.002), low-grade tumors ( p = 0.051), and involvement of one or two vertebral levels ( p = 0.038). Enneking appropriateness and surgical margin was not significantly associated with survival. Local recurrence was strongly related to mortality, with an odds ratio of 7.4. Conclusion This is the largest multicenter cohort of spinal chondrosarcomas. EI surgical management correlated with increased rates of local recurrence. This robust correlation strongly mandates to surgeons perform an EA resection with disease-free margins for spinal chondrosarcomas.
Osteosarcoma of the Spine: Prognostic Variables for Local Recurrence and Overall Survival, A Multicenter Ambispective Study
Authors: Clarke Michelle , Dekutoski Mark , Luzzati Alessandro , Rhines Laurence , Varga Peter , Rose Peter , Fisher Charles , Chou Dean , Fehlings Michael , Reynolds Jeremy , Williams Richard , Quraishi Nasir , Germscheid Niccole , Sciubba Daniel , Gokaslan Ziya , Boriani Stefano 
Published: May 2015

Introduction Primary spinal osteosarcomas are rare and aggressive neoplasms with poor outcomes. Enneking appropriate, en bloc resection is recommended for appendicular osteosarcomas. Obtaining even marginal margins is technically demanding in the spine, resulting in significant morbidity and possible functional sacrifice. The aim of this study was to identify prognostic variables on local recurrence and mortality, in surgically treated patients diagnosed with a primary osteosarcoma of the spine. Methods A multicenter ambispective database of surgically treated patients with primary spine osteosarcomas was developed by the AOSpine knowledge forum tumor. Patient demographic, diagnosis, treatment, perioperative morbidity, local recurrence, and cross-sectional survival data were collected. Tumors were classified according to Enneking principles and analyzed in the following two cohorts: Enneking appropriate (EA) and Enneking inappropriate (EI). EA was defined by the final pathology margin matching the Enneking recommended surgical margin and EI by not matching. Prognostic variables including age, previous spine tumor operation, biopsy type, spine level, tumor size, and chemotherapy timing were analyzed in reference to local recurrence and survival. Results Between 1987 and 2012, 57 patients (31 females and 26 males) underwent surgical treatment for a primary spinal osteosarcoma at a mean age of 36 ± 16 years. Patients were followed for a mean period of 3.4 ± 3.5 years (range, 0.5 days–14.3 years). Median survival for the entire cohort was 6.7 years postoperative. Overall, 24 (42%) patients died and 17 (30%) patients suffered a local recurrence, 10 (59%) of which died. Overall, 28 (52%) patients underwent EA resection while 26 (48%) patients were treated by EI resection. Median survival for patients with EA was 6.8 years postoperative, whereas median survival for EI patients was 3.7 years postoperatively ( p = 0.062). EI patients were at a higher risk of local recurrence than EA patients ( p = 0.002). Patient age, previous spine tumor operation, tumor size, spine level, and chemotherapy timing did not significantly influence recurrence and survival. Conclusion Osteosarcoma of the spine presents a significant challenge and most patients die from their disease in spite of aggressive surgery. There is a significant decrease in recurrence with en bloc resection when compared with intralesional resection.
Ewing Sarcoma of the Spine: Prognostic Variables for Survival and Local Control in Surgically Treated Patients
Authors: Rhines Laurence , Dirks Michael , Boriani Stefano , Luzzati Alessandro , Fehlings Michael , Fisher Charles , Dekutoski Mark , Williams Richard , Quraishi Nasir , Gokaslan Ziya , Bettegowda Chetan , Germscheid Niccole , Varga Peter 
Published: May 2015

Introduction Primary Ewing sarcoma of the spine is a challenging tumor to treat because of a high rate of local recurrence. The optimum role of surgery in the treatment of Ewing sarcoma is not clearly defined. The objective of this study was to analyze factors relevant to survival and local control in surgically treated patients diagnosed with primary Ewing sarcoma of the spine. Materials and Methods A multi-institutional international ambispective with cross-sectional follow-up data was gathered about patients who underwent surgery for primary Ewing sarcoma of the spine. The primary outcomes assessed were 5-year survival and local recurrence. Multiple variables including the Enneking appropriateness of the surgery were evaluated for relationships to the primary outcomes. An Enneking appropriate procedure for Ewing sarcoma is an en bloc resection with negative margins. Survival and recurrence were analyzed using Kaplan–Meier curves and log-rank tests. Results A total of 59 patients diagnosed with primary Ewing sarcoma of the spine underwent surgery. Enneking appropriateness of surgery was known for 55 patients; 30 treated Enneking appropriately (EA) and 25 treated Enneking inappropriately (EI). The 5-year survival was 73% ( n = 22) for EA patients and 48% ( n = 12) for EI patients. Median survival was not achieved within 5-year postoperative for EA patients and was 2.2 years for EI patients ( p = 0.124). Local recurrence occurred in 20% ( n = 6) of patients with an EA procedure versus 48% ( n = 11) of patients with an EI procedure. The rate of local control was favorable for EA-treated patients compared with EI-treated patients ( p = 0.046). Conclusion Primary spinal Ewing sarcoma requires multidisciplinary treatment. An Enneking appropriate surgical procedure is associated with longer survival and better local control. An Enneking appropriate procedure, when feasible, should be the surgical treatment of choice for primary spinal Ewing sarcoma.
Comparison of Clinical Outcomes for Anterior versus 360 Fusion at the Fusion Level of Lumbar Hybrid Surgery
Authors: Otero-Lopez Ernesto , Guyer Richard , Blumenthal Scott , Zigler Jack , Ohnmeiss Donna 
Published: May 2015

Introduction Options for treating two-level symptomatic disc degeneration after failure of nonoperative care includes fusion, total disc replacement (TDR), or a hybrid with fusion at one level and TDR at the other. Often the hybrid procedure involved an instrumented 360 fusion. However, the option for a standalone ALIF in a hybrid has rarely been addressed. The purpose of this study was to compare the outcomes of hybrid TDR/fusion surgery for ALIF versus 360 at the fusion level. Methods The study group included 135 patients undergoing hybrid surgery using TDR at one level and either ALIF ( n = 83) or instrumented 360 fusion ( n = 52) at the adjacent segment. The majority of cases were performed with TDR at L4–L5 and fusion at L5–S1. Only patients who had surgery at least 12 months before this study were included. The mean length of follow-up was similar in the two groups (∼24 months in both groups). Outcome measures included Oswestry Disability Index (ODI), visual analog scales (VAS) assessing back and leg pain, and reoperations. Results The mean operative blood loss was significantly less in the hybrid/ALIF group compared with the hybrid/360 group (71.7 vs. 142.1 mL; p < 0.01). The mean ODI scores before surgery were approximately 46 in both the groups. The scores improved significantly in both groups to the means of about 30 ( p < 0.01) with no significant difference between the two groups ( p > 0.40). Mean VAS back and leg pain scores also improved significantly in both groups with no significant differences between groups ( Fig. 1 ). [Figure: see text] The reoperation rate was significantly greater in the hybrid/360 group than in the hybrid/ALIF group (23.1 vs. 3.6%; p < 0.01). Reoperations in the hybrid/360 group included six reoperations for removal of painful posterior instrumentation, one to treat a wound infection, one decompression of the fusion level of the hybrid, three were for treatment of a symptomatic adjacent segment, and two were due to TDR malpositioning or displacement. Hybrid/ALIF reoperations included two patients undergoing decompression for stenosis and one underwent fusion two levels above the index surgery. Discussion This study found that the outcomes are similar between hybrids performed with ALIF versus 360 fusion adjacent to the TDR level with the exceptions of a significantly greater reoperation rate and mean blood loss in the hybrid/360 group. These results support that unless there is a defined indication for the posterior procedure, standalone ALIF is a viable option for lumbar hybrid surgery.
Tie2+ Cells of the Bovine Nucleus Pulposus are Progenitor Cells Capable of Differentiating into Osteocytes and Adipocytes
Authors: Tekari Adel , Chan Samantha , Wuertz Karin , Sakai Daisuke , Benneker Lorin M. , Grad Sibylle , Gantenbein Benjamin 
Published: May 2015

Introduction The intervertebral disc (IVD) has a limited regenerative potential and low back pain represents a leading cause of disability.1 IVD repair strategies require an appropriate cell source that is able to regenerate the damaged tissue such as progenitor stem cells. Recently, progenitor cells that are positive for the angiopoietin receptor (Tie2) in the nucleus pulposus were identified.2 These cells, which express type II collagen and aggrecan, were shown to have progenitor-like multipotency. Here, we isolated primary cells from bovine IVD aged 1 year and sorted bovine nucleus pulposus progenitor cells (NPPC) for the marker Tie2. Furthermore, we demonstrate that in contrast to Tie2− cells, Tie2+ expressing cells can differentiate into osteogenic and adipogenic lineages in vitro. Materials and Methods NP cells were obtained from 1-year-old bovine tails by sequential digestion with Pronase for 1 hour and collagenase overnight. Sorted Tie2− and Tie2+ cells were cultured in osteogenic and adipogenic medium containing 5% fetal bovine serum for 3 weeks. The formed cell layers from both subpopulations were stained for calcium deposition and fat droplets using alizarin red and red oil staining, respectively. Colony forming units (CFU) were prepared for both cell suspensions (Tie2− and Tie2 + ) in methylcellulose-based medium. The formed colonies (> 10 cells) were analyzed macroscopically and counted after 8 days. Results After 3 weeks of culture, sorted Tie2+ cells were able to differentiate into osteocytes and adipocytes as characterized by calcium deposition and fat droplet formation. By contrast, Tie2− cells generated a weak staining for calcium and no fat droplets were obtained ( Fig. 1 ). Sorted Tie2− and Tie2+ subpopulations of cells, both the formed colonies, however with different morphologies. The colonies formed from Tie2+ cells were spheroid in shape, whereas those fromTie2− cells were spread and fibroblastic. In addition, the highest frequency of the formed colonies was obtained for the Tie2+ cells after 8 days of culture in the methylcellulose-based medium. [Figure: see text] Conclusion Our data showed that Tie2+ cells of the nucleus pulposus cells are progenitor-like cells that are able to differentiate into osteogenic and adipogenic lineages. Sorting of NPPC for Tie2 may represent a promising strategy with the potential to be used in the clinics for treatment of intervertebral disc damage. Acknowledgments This project was funded by two projects of the Swiss National Science Foundation, grant numbers IZK0Z3_154384 and 310030_153411. References Freemont AJ. The cellular pathobiology of the degenerate intervertebral disc and discogenic back pain. Rheumatology (Oxford) 2009;48(1):5–10 Sakai D, Nakamura Y, Nakai T, et al. Exhaustion of nucleus pulposus progenitor cells with ageing and degeneration of the intervertebral disc. Nat Commun 2012;3:1264
Viable Cells Density and its Relationship with the Vascularization of the Endplate in Lumbar Discs
Authors: Martins Delio , Medeiros Valquiria , Paredes-Gamero Edgar , Buri Marcus , Wajchenberg Marcelo , Nader Helena , Puertas Eduardo , Faloppa Flavio 
Published: May 2015

Introduction The intervertebral disc is avascular and remains unknown if it has the capacity to maintain viable cells inside over the years. The vascularization of the endplate has a direct influence on the nutrition to the disc cells. This study aimed to analyze the vascularization of the endplate and its relation to the density of viable cells in lumbar intervertebral discs of young and old adult humans. Materials and Methods A total of 28 lumbar intervertebral discs were used and separated into two groups: Group 1 ( n = 15; younger than 50 years; Pfirrmann ≤ 3) and Group 2 ( n = 13; elder or equal to 80 years, Pfirrmann ≥ 4). Vascularization of the endplates was analyzed using Stereo Microscope Discovery V.8. Cell viability was assessed by MTT method. The cell density was measured by PicoGreen technique using amount of DNA as an estimate of total cell number. Results The viable cells remained steady in relation to the total cell density. The inferior endplate presented the highest number of holes ( p < 0.05). The greater number of cells was found in the annulus fibrosus ( p < 0.05). There was a positive correlation ( p < 0.05) between the density of viable cells and vascular openings in the inferior endplate. Conclusion The inferior endplate has the main supply of blood vessels to nourish the intervertebral disc and has direct bearing on the number of viable cells. Acknowledgments This work was supported by INFAR/UNIFESP Confocal and Flow Cytometry Facility and by grants from the “Fundacao de Amparo à Pesquisa do Estado de São Paulo” (FAPESP: Grant number: 2009/54793–6). D.E.M. was supported by a PhD's fellowship grant from CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nível Superior).
Characteristics and Mechanisms of Adjusting Spinopelvic Sagittal Balance in Patients with Thoracic and Thoracolumbar Kyphosis
Authors: Sun Zhuo Ran , Li Wei Shi , Chen Zhong Qiang 
Published: May 2015

Introduction This study determined the mechanisms of adjusting trunk sagittal balance and the impact of surgery on spinopelvic sagittal morphology and alignment in patients with thoracic and thoracolumbar kyphosis. Materials and Methods Whole spine and standing lateral radiographs of 49 Chinese patients with thoracic and thoracolumbar kyphosis were obtained before surgery, immediately after surgery, and in the final follow-up. A total of 171 asymptomatic Chinese adults were recruited as controls. The age at which the patients developed kyphotic deformity was recorded. The pelvic and spinal parameters were measured and the correlations of all parameters were analyzed. Results The mean age at which the patients developed kyphosis was 7.1 years. Preoperative mean pelvic incidence was 35.1 degrees, and mean pelvic tilt was −0.1 degrees, significantly less than those of normal subjects. Preoperative mean lumbar lordosis was 68.0 degrees, significantly higher than that of normal subjects. After surgery, kyphosis and lumbar hyperlordosis were significantly corrected, however, the preoperative and postoperative pelvic sagittal morphology and alignment made no difference, even in the final follow-up. There were no correlations between spinal and pelvic parameters before surgery. In the final follow-up, the correlations were recovered. Conclusion The mechanisms of adjusting the trunk sagittal balance in patients with thoracic and thoracolumbar kyphosis not only including pelvis anteverting, but also lumbar hyperlordosis. The latter serves as the main mechanism once skeletal maturation has been established. Although kyphosis and lumbar hyperlordosis were corrected by surgery, pelvic sagittal morphology remained unchanged. Surgery can reestablish the spinal sagittal balance and recover the correlations between spinal and pelvic parameters.
Lumbofemoral Angle: A Novel Sagittal Parameter Related to Quality of Life in Patients with Adult Scoliosis
Authors: Zhu Feng , Bao Hongda , Wang Bin , Zhu Zezhang , Liu Zhen , Yu Yang , Qian Bang-Ping , Sun Xu , Qiu Yong 
Published: May 2015

Introduction PT and PI-LL sometimes offer limited utility in daily practice when evaluating QOL, especially in outpatient clinics with limited time and equipment facility. This study proposes a novel spinopelvic parameter, lumbofemoral angle (LFA). The purpose of this study is to analyze the correlation between LFA and health-related (HRQOL) in adult scoliosis patients. Patients and Methods A cohort of 100 asymptomatic adult volunteers and 50 patients with adult scoliosis were prospectively recruited. The following sagittal parameters including thoracic kyphosis (TK), LL, LFA, PI, PT, and sacral slope (SS) were measured on the long-cassette standing upright lateral radiographs. HRQOL measures included the VAS, ODI, and SF-36 instruments for patients with adult scoliosis. Results LFA, the novel regional lumbosacral parameter, averaged 0.68 ± 4.5 degrees in normal adults with the 95% CI value of −7 to 7 degrees. Higher intra- and interobserver intraclass correlations (ICC) and less measurement time were observed in LFA compared with PI-LL indicating that it is easy to quantitatively evaluate the regional alignment directly from X-ray films. Although LFA in patients with adult scoliosis was found to be significantly larger (11.8 ± 8.7 vs. 0.68 ± 4.5 degrees, p < 0.001), it showed strong correlations with the PT and PI-LL in both groups ( p < 0.001). Additionally, a summary of significant correlations between LFA and QOL measurements were identified ( p < 0.05) Conclusion LFA could be considered a novel, user-friendly sagittal parameter, strongly correlated with previously established sagittal spinopelvic parameters and HRQOL measurements. LFA showed high inter- and intraobserver reliability, faster measurement times and could be easily identified and read. Mean LFA in asymptomatic adult patients was nearly 0 degrees with 95% CI value of −7 to 7 degrees, and significantly increased in adult scoliosis patients
Implant Instability, Proximal Fractures, Quality of Life, and Outcomes of Global Spinal Alignments Correction using Short Fusion in Adults and Elderly
Authors: Ptashnikov Dmitry , Mikhaylov Dmitry , Masevnin Sergei , Zaborovskii Nikita , Lapaeva Olga 
Published: May 2015

Introduction The purpose of our research is studying of incidence of implant instability, proximal fractures of instrumented and adjacent vertebras, and evaluation of health-related quality of life (HRQOL) parameters depending on extent of the sagittal balance correction after short fusion using a posterior approach. Patients and Methods A study of 83 patients with Type L (SRS-Schwab) deformity, operated in our institute was held in the period between 2008 and 2011. Patients were divided into two groups. The first retrospective group included 43 patients who underwent short fusion of lumbar curve from T12 or L1 to L5. The second prospective group consisted of 40 patients, which were treated using short fusion from T9 to S1 extending to the pelvis. Groups were evaluated with HRQOL-scales including VAS, ODI, SF36, and SRS-24. Radiographical assessment included Cobb coronal angle, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS), sagittal vertical axis (SVA). Radiographical, HRQOL-parameters and complications with a 3-year minimum follow-up were analyzed and compared between two groups. The comparisons were done by using independent sample Student t-test. A p-value of less than 0.05 was accepted as significant. Results In the first group the ideal sagittal balance was not achieved. The second group showed a better restoration of global spinal alignments compared with the first one ( p < 0.05). The HRQOL-scores (VAS, ODI, SF36, and SRS-24) of the patients after 3 years are slightly higher in the second group, but we did not get significant difference between groups ( p > 0.05). In the first group the number of complications in the form of implant instability ( n = 15, 35%) consists of loosening of screws at the end of fusion (T12/L1 or L4/5). The second group was obtained by a higher number of patients with complications ( n = 25, 63%) including loosening of screws at pelvis ( n = 15, 37.5%), proximal fractures of upper instrumented vertebra ( n = 7, 17.5%) and upper adjacent vertebra ( n = 8, 20%). Incidence of implant instability and proximal fractures in the second group was statistically more frequent ( p < 0.05). Conclusion The research showed that short fusion extending to the pelvis provided good sagittal balance, global spinal alignments, and likely HRQOL-parameters after 3 years follow-up. But, eventually, we obtained higher number of complications.