Can 3D-printed patient-specific instruments improve local control and overall survival in pelvic sarcoma? A clinical validation study. / Guías impresas en 3D: ¿mejoran el control local y la supervivencia global en el tratamiento de los sarcomas pélvicos? Estudio de validación clínica.

BACKGROUND AND OBJECTIVES: 3D-printed patient-specific instruments (PSIs), also known as 3D guides, have been shown to improve accuracy in resection of pelvic tumors in cadaver studies and achieve better surgical margins in vivo. This study evaluates the clinical impact of 3D-printed guides on medium-term local and distant disease control, as well as disease-free and overall survival in patients. MATERIAL AND METHODS: A cohort study included 25 patients with primary pelvic or sacral sarcomas: 10 in the 3D group and 15 in the control group, with a median follow-up of 47 months. Demographic and clinical data, including tumor histology, stage, resection technique, associated reconstruction, adjuvant therapies, and complications, were evaluated. Surgical margins (free, marginal, and contaminated) and relapse-free and overall survival curves were analyzed. RESULTS: The 3D group achieved a higher rate of free margins (80% vs 66.7%, p = 0.345). Local recurrence (50% vs 60%, P=.244) and distant disease relapse (20% vs 47%, p = 0.132) rates were lower in the 3D group. At the end of the follow-up, the 3D group had a higher overall survival rate (60% vs 40%, p = 0.327). The complication rate was similar in both groups, with a deep infection rate of 40%. CONCLUSIONS: The use of 3D guides in resecting primary pelvic tumors not only achieves a higher rate of free margins compared to conventional techniques but also shows a trend towards higher local, distant, and overall disease-free survival. Further studies with larger sample sizes and higher levels of evidence are necessary to validate these clinical trends.

Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica / Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery

Introducción: Los tumores del anillo pélvico suponen un reto por la dificultad de obtener márgenes quirúrgicos adecuados. Herramientas como la navegación quirúrgica o la impresión 3D para la fabricación de plantillas de posicionamiento quirúrgico paciente-específicas ayudan en la planificación preoperatoria y la ejecución intraoperatoria. Su correcta colocación es fundamental en localizaciones complejas como la pelvis, por lo que es necesario identificar los errores de posicionamiento. El objetivo de este estudio es demostrar la fiabilidad en la colocación de plantillas 3D para la realización de osteotomías en el anillo pélvico. Material y métodos: Estudio experimental en cadáver con 10 hemipelvis. Se realiza TC para la obtención del modelo tridimensional, planificación de osteotomías, diseño de plantillas de posicionamiento en rama isquiopubiana (I), iliopubiana (P), supracetabular (S) y cresta iliaca (C); y un marcador de posicionamiento (rigid-body) sobre las plantillas C y S para la navegación. Las plantillas y el rigid-body son impresos en 3D y se colocan según planificación previa. La navegación permite comprobar la posición final de las plantillas y de las osteotomías. Resultados: El posicionamiento de las plantillas respecto a la planificación preoperatoria varió dependiendo de la localización, siendo mayor el error en las de cresta iliaca. Utilizando la navegación, la media de error de distancia al plano de corte está en 3,5mm, excepto en pubis (5-8mm), estando condicionado por la posición del rigid body. Conclusión: El uso de plantillas paciente-específicas impresas en 3D es una herramienta fiable para la realización de osteotomías en cirugía oncológica pélvica.(AU)

Introduction: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. Material and methods: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. Results: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis 5-8mm), being conditioned by the position of the rigid body. Conclusion: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.(AU)

[Translated article] Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery / Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica

Introducción: Los tumores del anillo pélvico suponen un reto por la dificultad de obtener márgenes quirúrgicos adecuados. Herramientas como la navegación quirúrgica o la impresión 3D para la fabricación de plantillas de posicionamiento quirúrgico paciente-específicas ayudan en la planificación preoperatoria y la ejecución intraoperatoria. Su correcta colocación es fundamental en localizaciones complejas como la pelvis, por lo que es necesario identificar los errores de posicionamiento. El objetivo de este estudio es demostrar la fiabilidad en la colocación de plantillas 3D para la realización de osteotomías en el anillo pélvico. Material y métodos: Estudio experimental en cadáver con 10 hemipelvis. Se realiza TC para la obtención del modelo tridimensional, planificación de osteotomías, diseño de plantillas de posicionamiento en rama isquiopubiana (I), iliopubiana (P), supracetabular (S) y cresta iliaca (C); y un marcador de posicionamiento (rigid-body) sobre las plantillas C y S para la navegación. Las plantillas y el rigid-body son impresos en 3D y se colocan según planificación previa. La navegación permite comprobar la posición final de las plantillas y de las osteotomías. Resultados: El posicionamiento de las plantillas respecto a la planificación preoperatoria varió dependiendo de la localización, siendo mayor el error en las de cresta iliaca. Utilizando la navegación, la media de error de distancia al plano de corte está en 3,5mm, excepto en pubis (5-8mm), estando condicionado por la posición del rigid body. Conclusión: El uso de plantillas paciente-específicas impresas en 3D es una herramienta fiable para la realización de osteotomías en cirugía oncológica pélvica.(AU)

Introduction: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. Material and methods: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. Results: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis 5-8mm), being conditioned by the position of the rigid body. Conclusion: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.(AU)

[Translated article] Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery.

INTRODUCTION: Pelvic ring tumours pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery. / Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica.

INTRODUCTION: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

Hemipelvectomías tras sarcomas de localización pélvica de alto grado: pronóstico en condrosarcomas frente a otros tipos histológicos / Hemipelvectomy for the treatment of high-grade sarcomas: Pronostic of chondrosarcomas compared to other histological types

Introducción. La baja incidencia y la heterogeneidad histológica de los sarcomas pélvicos primarios dificulta el análisis y publicación de cohortes homogéneas. Objetivo. Describir el pronóstico vital y funcional dependiendo del tipo histológico en una serie de sarcomas primarios de localización pélvica de alto grado localmente avanzados tratados mediante hemipelvectomía. Material y métodos. Estudio descriptivo, epidemiológico y funcional de 15 casos tratados entre 2006-2012. Se realizó análisis de supervivencia, valoración funcional y estudio comparativo en función del tipo histológico, comparando los condrosarcomas frente al resto de diagnósticos histológicos. Resultados. El tipo histológico más frecuente en la serie fue el condrosarcoma (46%), y la localización más frecuente la zona P2 (periacetabular) (73%). Se realizó una hemipelvectomía interna en el 66% de los casos, siendo mayor (83%) en el caso de los condrosarcomas. La supervivencia global a los 2 años fue del 54%, siendo más elevada en el grupo condrosarcoma (67%) que en el resto (43%). La situación funcional dependió del tipo de intervención, sin encontrar diferencias en función del tipo histológico ni de la realización de reconstrucción. Discusión y conclusiones. La hemipelvectomía como procedimiento quirúrgico está indicada para el tratamiento de los sarcomas primarios de localización pélvica de alto grado localmente avanzados independientemente del tipo histológico. La incidencia de conservación del miembro y la supervivencia global es mayor en los condrosarcomas frente al resto de tipos histológicos (AU)

Introduction. The low incidence and histological heterogeneity of primary sarcomas located in the pelvis makes it difficult to find homogeneous cohorts. Objective. To describe the life and functional prognosis depending on the histological type of sarcoma in a series of locally advanced high-grade pelvis located sarcomas treated by hemipelvectomy. Methods. A descriptive epidemiological and functional study was conducted on 15 cases treated between 2006 and 2012. Survival analysis, functional assessment, and a comparative study by histological type were performed, comparing chondrosarcomas to other histological diagnoses. Results. The most frequent histological type was chondrosarcoma (46%), and the most frequent location was P2 (periacetabular) (73%). An internal hemipelvectomy was performed in 66% of cases, with a higher incidence (83%) in chondrosarcomas. Overall two-year survival was 54%, with higher survival in the chondrosarcoma group (67%) than in the other sarcomas (43%). Functional status depended on the type of intervention, with no differences in histological type or the performance of the reconstruction. Discussion and conclusions. Hemipelvectomy is a surgical procedure that is indicated for the treatment of locally advanced high grade pelvis located sarcomas, regardless of histological type. The incidence of limb preservation and overall survival is higher in chondrosarcomas compared to other sarcomas (AU)

[Hemipelvectomy for the treatment of high-grade sarcomas: Pronostic of chondrosarcomas compared to other histological types]. / Hemipelvectomías tras sarcomas de localización pélvica de alto grado: pronóstico en condrosarcomas frente a otros tipos histológicos.

INTRODUCTION: The low incidence and histological heterogeneity of primary sarcomas located in the pelvis makes it difficult to find homogeneous cohorts. OBJECTIVE: To describe the life and functional prognosis depending on the histological type of sarcoma in a series of locally advanced high-grade pelvis located sarcomas treated by hemipelvectomy. METHODS: A descriptive epidemiological and functional study was conducted on 15 cases treated between 2006 and 2012. Survival analysis, functional assessment, and a comparative study by histological type were performed, comparing chondrosarcomas to other histological diagnoses. RESULTS: The most frequent histological type was chondrosarcoma (46%), and the most frequent location was P2 (periacetabular) (73%). An internal hemipelvectomy was performed in 66% of cases, with a higher incidence (83%) in chondrosarcomas. Overall two-year survival was 54%, with higher survival in the chondrosarcoma group (67%) than in the other sarcomas (43%). Functional status depended on the type of intervention, with no differences in histological type or the performance of the reconstruction. DISCUSSION AND CONCLUSIONS: Hemipelvectomy is a surgical procedure that is indicated for the treatment of locally advanced high grade pelvis located sarcomas, regardless of histological type. The incidence of limb preservation and overall survival is higher in chondrosarcomas compared to other sarcomas.

Artropatía neuropática de hombro asociada a siringomielia / Artrophatic neuropathy of the shoulder associated to syringomyelia

Se presenta un caso del conocido como hombro de Chopart, una artropatía neuropática como consecuencia de siringomielia en una paciente de 62 años con antecedentes durante 5 años en su hombro. La clínica y la RMN de la columna cervical permitieron el diagnóstico. El tratamiento fue conservador con una buena evolución (AU)

A case of Chopart shoulder, a neuropathic shoulder arthropathy associated with syringomyelia, was detected in a 62 years old woman with five years shoulder clinic. The clinical examination and a cervical MRI detected the ethiology. The treatment was functional with a good outcome (AU)

Indications for use of the long Gamma nail.

A retrospective analysis of 42 patients treated by intramedullary nailing with the Gamma nail with a mean followup of 22.4 months is reported. The indications for the use of this nail were subtrochanteric fractures in 31 cases, diaphyseal femoral fractures in 10 cases, and segmental fracture in one case. Seven cases of the diaphyseal fractures were renailings for a previously placed nail. There was one pathologic fracture in the subtrochanteric group and three in the diaphyseal group. The indications of this new technique and its complications are analyzed.