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Browsing by Author "Urrutia, Julio"

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An independent inter- and intra-observer agreement assessment of the Eno classification of sacroiliac joint degeneration
(2022) Urrutia, Julio; Camino-Willhuber, Gaston; Astur, Nelson; Valacco, Marcelo; Borensztein, Matias; Velan, Osvaldo; Cikutovic, Pablo
Background Recently, a scoring system to grade sacroiliac joint (SIJ) degeneration using computed tomography (CT) scans was described. No independent evaluation has determined the inter- and intra-observer agreement using this scheme. Purpose To perform an independent inter- and intra-observer agreement assessment using the Eno classification and determining gas in the SIJ. Material and Methods We studied 64 patients aged >= 60 years who were evaluated with abdominal and pelvic computed tomography scans. Six physicians (three orthopaedic spine surgeons and three musculoskeletal radiologists) assessed axial images to grade SIJ degeneration into grade 0 (normal), grade 1 (mild degeneration), grade 2 (significant degeneration), and grade 3 (ankylosis). We also evaluated the agreement assessing the presence of gas in the SIJ. After a four-week interval, all cases were presented in a random sequence for repeat assessment. We determined the agreement using the kappa (kappa) or weighted kappa coefficient (w kappa). Results The inter-observer agreement was moderate (w kappa = 0.50 [0.44-0.56]), without differences among surgeons (w kappa = 0.53 [0.45-0.61]) and radiologists (w kappa = 0.49 [0.42-0.57]). The agreement evaluating the presence of gas was also moderate (kappa = 0.45 [0.35-0.54]), but radiologists obtained better agreement (kappa = 0.61 [0.48-0.72]) than surgeons (kappa = 0.29 [0.18-0.39]). The intra-observer agreement using the classification was substantial (w kappa = 0.79 [0.76-0.82]), without differences comparing surgeons (w kappa = 0.75 [0.70-0.80]) and radiologists (w kappa = 0.83 [0.79-0.87]). The intra-rater agreement evaluating gas was substantial (kappa = 0.77 [0.72-0.82]), without differences between surgeons (kappa = 0.71 [0.63-0.78]) and radiologists (kappa = 0.84 [0.78-0.90]). Conclusion Given the only moderate agreement obtained using the Eno classification, it does not seem adequate to be used in clinical practice or in research.
An independent inter- and intraobserver agreement assessment of the AOSpine sacral fracture classification system
(2021) Urrutia, Julio; Meissner-Haecker, Arturo; Astur, Nelson; Valencia, Manuel; Yurac, Ratko; Camino-Willhuber, Gaston; Valacco, Marcelo
BACKGROUND CONTEXT: The AOSpine sacral classification scheme was recently described. It demonstrated substantial interobserver and excellent intraobserver agreement in the study describing it; however, an independent assessment has not been performed.
An inter- and intra-rater agreement assessment of a novel classification of pyogenic spinal infections
(2022) Camino-Willhuber, Gaston; Delgado, Byron; Astur, Nelson; Guiroy, Alfredo; Valacco, Marcelo; Nasto, Luigi Aurelio; Piccone, Luca; Barbanti-Brodano, Giovanni; Leone, Antonio; Cipolloni, Valerio; Pola, Enrico; Urrutia, Julio
Purpose Pola et al. described a clinical-radiological classification of pyogenic spinal infections (PSI) based on magnetic resonance imaging (MRI) features including vertebral destruction, soft tissue involvement, and epidural abscess, along with the neurological status. We performed an inter- and intra-observer agreement evaluation of this classification. Methods Complete MRI studies of 80 patients with PSI were selected and classified using the scheme described by Pola et al. by seven evaluators. After a four-week interval, all cases were presented to the same assessors in a random sequence for repeat assessment. We used the weighted kappa statistics (w kappa) to establish the inter- and intra-observer agreement. Results The inter-observer agreement was substantial considering the main categories (w kappa = 0.77; 0.71-0.82), but moderate considering the subtypes (w kappa = 0.51; 0.45-0.58). The intra-observer agreement was substantial considering the main types (w kappa = 0.65; 0.59-0.71), and moderate considering the subtypes (w kappa = 0.58; 0.54-0.63). Conclusion The agreement at the main type level indicates that this classification allows adequate communication and may be used in clinical practice; at the subtypes level, the agreement is only moderate.
An international consensus based on the Delphi method to define failure of medical treatment in pyogenic spinal infections
(2024) Urrutia, Julio; Camino-Willhuber, Gaston; Guerrero, Alonso; Diaz-Ledezma, Claudio; Bono, Christopher M.
BACKGROUND CONTEXT: Pyogenic spinal infections (PSIs) are severe conditions with high morbidity and mortality. If medical treatment fails, patients may require surgery, but there is no consensus regarding the definition of medical treatment failure. PURPOSE: To determine criteria for defining failure of medical treatment in PSI through an international consensus of experts. STUDY DESIGN: A two -round basic Delphi method study. SAMPLE: One hundred and fifty experts from 22 countries (authors or co-authors of clinical guidelines or indexed publications on the topic) were invited to participate; 33 answered both rounds defining the criteria. OUTCOME MEASURES: A scale of 1 to 9 (1: no relevance; 9: highly relevant) applied to each criterion. METHODS: We created an online survey with 10 criteria reported in the literature to define the failure of medical treatment in PSIs. We sent this survey via email to the experts. Agreement among the participants on relevant criteria (score >= 7) was determined. One month later, the second round of evaluations was sent. An extra criterion suggested by six responders in the first round was incorporated. The final version was reached with the criteria considered relevant and with high agreement. RESULTS: The consensus definition is: (1) There is an uncontrolled sepsis despite broad spectrum antibiotic treatment, and (2) There is an infection relapse, following a six -week period of antibiotics with clinical and laboratory improvement. CONCLUSIONS: Our definition of failure following nonsurgical treatment of PSI can offer a standardized approach to guide clinical decision -making. Furthermore, it has the potential to enhance scientific reporting within this field. (c) 2023 Elsevier Inc. All rights reserved.
Autograft versus allograft with or without demineralized bone matrix in posterolateral lumbar fusion in rabbits - Laboratory investigation
(AMER ASSOC NEUROLOGICAL SURGEONS, 2008) Urrutia, Julio; Thumm, Nicolas; Apablaza, Daniel; Pizarro, Felipe; Zylberberg, Alejandro; Quezada, Felipe
Object. Posterolateral spinal fusions are performed to treat different spinal disorders. Autograft continues to be the gold standard; it is, however, associated with donor site morbidity and limited sources. Allograft has been used, but has been reported to result in lower fusion rates. Demineralized bone matrix (DBM) has also been used and reportedly increases the fusion rate in a variety of critical defect models. Different forms of DBM are available, not all have been independently studied. To evaluate the effect of a xenogenic DBM added to allograft on the fusion rate of posterolateral lumbar spine arthrodesis the authors designed an experimental study comparing posterolateral fusion rate using autograft, allograft, and allograft plus a xenogenic DBM in a validated animal model.
Automatic quantification of fat infiltration in paraspinal muscles using T2-weighted images: An OsiriX application
(ELSEVIER SCI LTD, 2020) Arrieta, Cristobal; Urrutia, Julio; Besa, Pablo; Montalba, Cristian; Lafont, Nelson; Andia, Marcelo E.; Uribe, Sergio
Fat infiltration of paraspinal muscles has been related with low back pain and quantified using T2w MR images and manual segmentation techniques. This methodology is time consuming and has low reproducibility. Moreover, the accuracy of T2w images to quantify fat has not been validated. This paper presents the development and validation of an OsiriX application to semi-automatically segment infiltrated fat on T2w images. This software was also utilized to validate the quantification of muscle fat infiltration with T2w images, considering Dixon fat images assessments as a gold standard.
Can the Surgical Apgar Score predict morbidity and mortality in general orthopaedic surgery?
(2012) Urrutia, Julio; Valdes, Macarena; Zamora, Tomas; Canessa, Valentina; Briceno, Jorge
Purpose The Surgical Apgar Score (SAS) is a simple tally based on intra-operative heart rate, blood pressure and blood loss; it predicts 30-day major postoperative complications and mortality in different surgical fields, but no validation has been performed in general orthopaedic surgery.
Chronic Liver Failure and Concomitant Distant Infections Are Associated With High Rates of Neurological Involvement in Pyogenic Spinal Infections
(LIPPINCOTT WILLIAMS & WILKINS, 2009) Urrutia, Julio; Bono, Christopher M.; Mery, Pablo; Rojas, Claudio; Gana, Natalia; Campos, Mauricio
Study Design. A retrospective study of a consecutive series of all patients with pyogenic spinal infections treated at a single institution over a 10-year period.
Classifications in Brief: The AOSpine Sacral Classification System
(2022) Camino-Willhuber, Gaston; Urrutia, Julio
Clinical and imaging findings in patients with aggressive spinal hemangioma requiring surgical treatment
(ELSEVIER SCI LTD, 2011) Urrutia, Julio; Postigo, Roberto; Larrondo, Roberto; San Martin, Aliro
Vertebral hemangiomas (VHS) are frequently asymptomatic lesions found incidentally during investigations for other spinal problems. Symptomatic VHs are less common, and there are few reports of compressive VHs in the literature. VHs with aggressive behavior present with low signal intensity on T1-weighted and high signal intensity on T2-weighted MRI. We present a case series of four patients with compressive VH, all of whom were neurologically compromised. Each of the four patients underwent pre-operative arterial embolization followed by surgical treatment of their VHs. All patients recovered normal motor function after surgery. At follow-up (average 53 months), one patient had a recurrent tumor requiring reoperation and radiotherapy. Although it is rare, aggressive VH can be a devastating condition. Total surgical resection or subtotal resection with radiotherapy may be warranted. (C) 2010 Elsevier Ltd. All rights reserved.
Cultured autologous bone marrow stem cells inhibit bony fusion in a rabbit model of posterolateral lumbar fusion with autologous bone graft
(ELSEVIER SCI LTD, 2010) Urrutia, Julio; Mery, Pablo; Martinez, Rafael; Pizarro, Felipe; Apablaza, Daniel; Mardones, Rodrigo
Mesenchymal stem cells (MSCs) have been isolated from various tissues and expanded in culture. MSCs add osteogenic potential to ceramic scaffolds when used together. A spinal fusion rabbit model was used to evaluate whether a pellet of cultured, autologous bone marrow MSCs (BMSCs) with osteogenic differentiation could increase the fusion rate when co-grafted with an autologus bone graft compared to autograft alone. Thirty rabbits were randomly assigned to two groups. Group I received bone autograft alone and Group 2 received bone autograft plus a pellet of cultured and differentiated BMSCs. Group 2 rabbits had a bone marrow puncture, after which the BMSC were cultured and osteoblastic differentiation was induced. BMSC cultures were obtained from 12 of 15 rabbits. The 27 rabbits underwent a bilateral, L4-L5 intertransverse fusion with an autograft and in Group 2 rabbits a pellet of differentiated BMSCs was added to the autograft. In Group 1, the fusion rate was 53% (8 of 15 rabbits) and ill Group 2 the fusion rate was 0% (p < 0.05). Adding differentiated BMSCs in a pellet without a scaffold not only failed to increase fusion rate, but completely inhibited bony growth. (C) 2009 Elsevier Ltd. All rights reserved.
DNA methylation profile in diffuse type gastric cancer: evidence for hypermethylation of the BRCA 1 promoter region in early-onset gastric carcinogenesis
(SOC BIOLGIA CHILE, 2008) Bernal, Carolina; Vargas, Macarena; Ossandon, Francisco; Santibanez, Eudocia; Urrutia, Julio; Luengo, Victor; Zavala, Luis F.; Backhouse, Claudia; Palma, Mariana; Argandona, Jorge; Aguayo, Francisco; Corvalan, Alejandro
Diffuse type gastric carcinoma is the most aggressive type of gastric cancer. This type Of tumor is not preceded by precancerous changes and is associated with carly-onset and hereditary syndromes. To test the hypothesis that DNA methylation profile Would be useful for molecular classification of the diffuse type gastric carcinoma, DNA methylation patterns of the CpG Island of 17 genes were studied in 104 cases and 47 normal adjacent gastric mucosa by Methylation-specific PCR, Immunohistochemistry and Hierarchical Clustering analysis. The most frequent methylated genes were FHIT, E-cadherin, BRCA1 and APC (>50%), followed by p14, p16, p15, p73, MGMT and SEMA3B (20-49%). Hierarchical clustering analysis reveals four groups with different clinical features. The first was characterized by hypermethylation of BRCA 1 and younger age (<45 years old), and the second by hypermethylation of p14 and p 16 genes, male. predominance and Epstein-Barr virus infection. The third group was characterized by hypermethylation of FHIT and antrum located tumors and the fourth was not associated with any clinical variables. In normal adjacent mucosa only the p73 gene was significantly less methylated in comparison to tumor mucosa. DNA methylation identified subgroups of diffuse type gastric cancer. Hypermethylation of BRCA I associated with Young age suggests a role in early-onset gastric carcinoma.
Do corticosteroids affect lumbar spinal fusion? A rabbit model using high-dose methylprednisolone
(SPRINGER TOKYO, 2011) Urrutia, Julio; Carmona, Maximiliano; Briceno, Jorge
The effect of corticosteroids on spinal fusion healing has not yet been determined. To evaluate the effect of corticosteroids on lumbar spinal fusion we designed a randomized, placebo-controlled animal study using high-dose methylprednisolone sodium succinate, which is widely used in patients with spinal cord injury who are undergoing spinal fusion.
Early histologic changes following polymethylmethacrylate injection (Vertebroplasty) in rabbit lumbar vertebrae
(LIPPINCOTT WILLIAMS & WILKINS, 2008) Urrutia, Julio; Bono, Christopher M.; Mery, Pablo; Rojas, Claudio
Study Design. An ex vivo histologic study in rabbits.
Effect of a single dose of pamidronate administered at the time of surgery in a rabbit posterolateral spinal fusion model
(2010) Urrutia, Julio; Briceno, Jorge; Carmona, Maximiliano; Olavarria, Fernando; Hodgson, Felipe
Spinal fusion is usually performed on patients who receive bisphosphonates (BP); however, limited data on their action on spinal fusion are available. Previous studies in animal models have shown that chronic administrations of BP reduced spinal fusion rates, and only one study has shown that a single dose administration of zolendronic acid increased fusion rate. The objective of the present study was to evaluate if pamidronate (PA), which was previously demonstrated to reduce spinal fusion rate when administered continuously for 8 weeks, would increase the spinal fusion rate if administered in a single dose at the time of surgery in a rabbit model. Thirty-two New Zealand rabbits underwent an L5-L6 posterolateral intertransverse fusion with iliac crest autograft. Animals were randomized to receive either PA 3 mg/kg in a single dose immediately after surgery, or normal saline. Animals were killed 8 weeks after surgery and fusion was determined by manual palpation and radiographic analysis. Fusion healing was obtained in eight rabbits (50%) in the PA group and in four animals (25%) in the control group, p = 0.137. In a rabbit model, a single dose of PA did not decrease lumbar spinal arthrodesis consolidation rates, but it obtained a nonsignificant higher spinal fusion rate.
Extensive epidural abscess with surgical treatment and long term follow up
(ELSEVIER SCIENCE INC, 2007) Urrutia, Julio; Rojas, Claudio
BACKGROUND CONTEXT: Spinal epidural abscess is an uncommon infection. There are few reports on extensive epidural abscesses. PURPOSE: We report a case of an epidural abscess extending from C2 to the sacrum, with a longterm follow-up.
Factors associated with variability in length of sick leave because of acute low back pain in Chile
(ELSEVIER SCIENCE INC, 2009) Diaz Ledezma, Claudio; Urrutia, Julio; Romeo, Jose; Chelen, Alfonso; Gonzalez Wilhelm, Leonardo; Lavarello, Cristian
BACKGROUND CONTEXT: Acute low back pain (LBP) is a frequent cause of physician visits and sick leave. Patients with longer sick leave account for most costs associated with LBP. Most research on risk factors for prolonged sick leave because of LBP has been done in Anglo-Saxon or Northern European populations with occupational LBP. Few studies have been conducted in less affluent Latin countries.
Inter- and intra-observer agreement using the new AOSpine sacral fracture classification, with a comparison between spine and pelvic trauma surgeons
(2022) Meissner-Haecker, Arturo; Diaz-Ledezma, Claudio; Klaber, Ianiv; Zamora, Tomas; Valencia, Manuel; Camino-Willhuber, Gaston; Astur, Nelson; Yurac, Ratko; Valacco, Marcelo; Urrutia, Julio
Background: Sacral fractures treatment frequently involves both spine and pelvic trauma surgeons; therefore, a consistent communication among surgical specialists is required. We independently assessed the new AOSpine sacral fracture classification's agreement from the perspective of spine and pelvic trauma surgeons. Methods: Complete computerized tomography (CT) scans of 80 patients with sacral fractures were selected and classified using the new AOSpine sacral classification system by six spine surgeons and three pelvic trauma surgeons. After four weeks, the 80 cases were presented and reassessed by the same raters in a new random sequence. The Kappa coefficient ( K) was used to measure the inter-and intra-observer agreement. Results: The inter-observer agreement considering the fracture severity types (A, B, or C) was substantial for spine surgeons ( K= 0.68 [0.63 - 0.72]) and pelvic trauma surgeons ( K= 0.74 (0.64 - 0.84). Regarding the subtypes, both groups achieved moderate agreement with K= 0.52 (0.49 - 0.54) for spine surgeons and K= 0.51 (0.45 - 0.57) for pelvic trauma surgeons. The intra-observer agreement considering the fracture types was substantial for spine surgeons ( K= 0.74 [0.63 - 0.75]) and almost perfect for pelvic trauma surgeons ( K= 0.84 [0.74 - 0.93]). Concerning the subtypes, both groups achieved substantial agreement with, K= 0.61 (0.56 - 0.67) for spine surgeons and K= 0.68 (0.62 - 0.74) for pelvic trauma surgeons. Conclusion: This classification allows an adequate communication for spine surgeons and pelvic trauma surgeons at the fracture severity type, but the agreement is only moderate at the subtype level. Future prospective studies are required to evaluate whether this classification allows for treatment recommendations and establishing prognosis in patients with sacral fractures. @ 2021 Elsevier Ltd. All rights reserved.
Lumbar Scoliosis in Postmenopausal Women: Prevalence and Relationship With Bone Density, Age, and Body Mass Index
(LIPPINCOTT WILLIAMS & WILKINS, 2011) Urrutia, Julio; Diaz Ledezma, Claudio; Espinosa, Julio; Berven, Sigurd H.
Study Design. Cross-sectional study.
Postoperative lumbar spine: modified radiographic projections for detection of bone defects in cadavers
(AVES, 2009) Yeh, Lee Ren; Urrutia, Julio; Sartoris, David; Garfin, Steven; Lektrakul, Nittaya; Resnick, Donald
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