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.

The knee prosthesis constraint dilemma: Biomechanical comparison between varus-valgus constrained implants and rotating hinge prosthesis. A cadaver study.

The real degree of constriction of rotating hinge knee (RHK) and condylar constrained prostheses (CCK) is a matter of discussion in revision knee arthroplasty. The objectives of this study are to compare the tibial rotation of both implants and validate the use of inertial sensors with optical tracking system as movement measurement tools. A total of 16 cadaver knees were used. Eight knees were replaced using a RHK (Endomodel LINK), and the remaining eight received a CCK prosthesis (LCCK, Zimmer). Tibial rotation range of motion was measured in full extension and at 30°, 60°, and 90° of flexion, with four continuous waveforms for each measurement. Measurements were made using two inertial sensors with specific software and compared with measurements obtained using the gold standard technique - the motion capture camera. The comparison of the accuracy of both measurement methods showed no statistically significant differences between inertial sensors and motion capture cameras, with p > .1; the mean error for tibial rotation was 0.21°. Tibial rotation in the RHK was significantly greater than in the CCK (5.25° vs. 2.28°, respectively), p < .05. We have shown that RHK permit greater tibial rotation, being closer to physiological values than CCKs. Inertial sensors have been validated as an effective and accurate method of measuring knee movement. The clinical significance: RHK appears to represent a lower constriction degree than CCK systems.

Role of the orthopaedic surgeon in 3D printing: current applications and legal issues for a personalized medicine. / Papel del cirujano ortopédico y traumatólogo en la impresión 3D: aplicaciones actuales y aspectos legales para una medicina personalizada.

3D printing (I3D) is an additive manufacturing technology with a growing interest in medicine and especially in the specialty of orthopaedic surgery and traumatology. There are numerous applications that add value to the personalised treatment of patients: advanced preoperative planning, surgeries with specific tools for each patient, customised orthotic treatments, personalised implants or prostheses and innovative development in the field of bone and cartilage tissue engineering. This paper provides an update on the role that the orthopaedic surgeon and traumatologist plays as a user and prescriber of this technology and a review of the stages required for the correct integration of I3D into the hospital care flow, from the necessary resources to the current legal recommendations.

Biarticular total femoral spacer for complete bone loss in periprosthetic joint infection. A technical modification. / Espaciador femoral total biarticulado para el tratamiento de la infección periprotésica de cadera y rodilla con pérdida completa de hueso. Modificación técnica.

BACKGROUND: The management of complete bone defects in hip and knee periprosthetic infection is still a real surgical challenge. MATERIAL AND METHODS: We present a technical modification for performing a biarticular total femoral spacer with a femoral nail without the need to approach the proximal tibia. RESULTS: Three patients were operated with this technique. There was no intraoperative complication. The infection was resolved in all patients operated at final follow-up. All patients improved their previous functional situation and could walk with different aids. CONCLUSIONS: This technical modification is an alternative for cases where it is necessary to resect the complete femur, but it is not necessary to approach the tibia.

Role of intraoperative radiotherapy in the treatment of sacral chordoma.

BACKGROUND CONTEXT: Sacral chordoma is a rare entity with high local recurrence rates when complete resection is not achieved. To date, there are no series available in literature combining surgery and intraoperative radiotherapy (IORT). PURPOSE: The objective of this study was to report the experience of our center in the management of sacral chordoma combining radical resection with both external radiotherapy and IORT. STUDY DESIGN: This is a retrospective case series. PATIENT SAMPLE: The patient sample included 15 patients with sacral chordoma resected in our center from 1998 to 2015. OUTCOME MEASURES: The outcome measures were overall survival (OS), disease-free survival (DFS), and rates of local and distant recurrences. METHODS: We retrospectively reviewed the records of all the patients with sacral chordoma resected in our center from 1998 to December 2015. Overall survival, DFS, and rates of local and distant recurrences were calculated. Results between patients treated with or without IORT were compared. RESULTS: A total of 15 patients were identified: 8 men and 7 women. The median age was 59 years (range 28-77). Intraoperative radiotherapy was applied in nine patients and six were treated with surgical resection without IORT. In 13 patients, we performed the treatment of the primary tumor, and in two patients, we performed the treatment of recurrence disease. A posterior approach was used in four patients. Wide surgical margins (zero residue) were achieved in six patients, marginal margins (microscopic residue) were achieved in seven patients, and there were no patients with intralesional (R2) margins. At a median follow-up of 38 months (range 11-209 months), the 5-year OS in the IORT group was 100% versus 53% in the group of non-IORT (p=.05). The median DFS in the IORT group was 85 months, and that in the non-IORT group was 41 months. In the group without IORT, two patients died and nobody died during the follow-up in the group treated with IORT. High-sacrectomy treated patients had a median survival of 41 months, and low-sacrectomy treated patients had a median survival of 90 months. Disease-free survival in patients without gluteal involvement was 100% at 5 years, and that in patients with gluteal involvement was 40%. All patients with a recurrence in our study had gluteal involvement. CONCLUSIONS: Multidisciplinary management of sacral chordoma seems to improve local control. The use of IORT, in our experience, is associated with an increase in OS and DFS. The level of resection and gluteal involvement seems to affect survival. The posterior approach is useful in selected cases. Multicenter studies should be performed to confirm the utility of IORT.

[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.

Reconstrucción del ligamento cruzado anterior / Reconstruction of the anterior cruciate ligament

Las técnicas actuales de reconstrucción del ligamento cruzado anterior restauran la función normal de la rodilla, disminuyen el riesgo de gonartrosis y presentan resultados clínicos satisfactorios en más de un 90% de los casos. La técnica influye de forma decisiva en el éxito, estando íntimamente relacionada con la respuesta biológica del injerto. Los fracasos en su mayoría se deben a errores en la realización de los túneles o la fijación de la plastia. El estudio detenido de los pacientes insatisfechos a pesar de una técnica impecable nos debe de llevar a mejorar aún esta cirugía en un futuro para acercarnos más a la biomecánica del LCA nativo (AU)

The current techniques for reconstruction of the anterior cruciate ligament restore normal knee function, reduce the risk of gonarthrosis, and offer satisfactory clinical results in over 90% of all cases. The technique used exerts a decisive influence upon the success of treatment, which in turn is intimately linked to biological graft response. Most failures are due to error in performing the tunnels or in fixing plasty. Careful evaluation of patients who are dissatisfied despite a perfectly executed technique should contribute to improve this surgery even further, in order to more closely reproduce the biomechanics of the native anterior cruciate ligament (AU)

Tratamiento quirúrgico de las luxaciones acromioclaviculares con la técnica de Phemister. Revisión de resultados a largo plazo / Surgical treatment of acromioclavicular luxations using Phemister technique. Revision of long term results

Introducción y objetivos: A lo largo de la historia se han desarrollado multitud de tratamientos tanto quirúrgicos como no quirúrgicos. Hoy en día sigue sin existir acuerdo sobre el tratamiento de esta patología. A pesar de existir mucha literatura al respecto muy pocos artículos hacen referencia a resultados a largo plazo y menos a los resultados específicos obtenidos con la técnica de Phemister El objetivo del presente trabajo consiste en evaluar el resultado, a largo plazo, radiológico, funcional, estético y la satisfacción global de los pacientes tras la técnica de Phemister. Material y métodos: Se ha realizado un estudio retrospectivo sobre el total de intervenciones tipo Phemister realizadas entre el 1 de enero de 1996 y el 12 de diciembre de 1996. El estudio radiológico se ha realizado mediante cinco parámetros: La anchura de la articulación acromioclavicular, la distancia coracoclavicular, el aumento del espacio coracoclavicular, el desplazamiento vertical de la clavícula y el porcentaje de desplazamiento vertical de la clavícula respecto a la articulación acromioclavicular. El estudio funcional se ha realizado con el test de Imatani. El resultado estético se ha realizado teniendo en cuenta el desplazamiento vertical de la clavícula y las características de la cicatriz La satisfacción del paciente se ha estimado mediante una escala analógica. Resultado y conclusiones: Radiológicamente se obtiene muy buen resultado postoperatorio inmediato, pero a los 9 años la luxación recidiva hasta en un 66% de los pacientes. Sólo un 66% de los pacientes tienen un resultado funcional satisfactorio. Las alteraciones estéticas a los 9 años ocurren en un 66% de los pacientes, con prominencia del extremo distal de la clavícula y con cicatrices hipertróficas. Sin embargo, la satisfacción objetiva de los pacientes es muy buena

Background and purpose: Many surgical and conservative treatments have been developed for acromioclavicular joint injuries through last decades. Nowadays there is controversy surrounding the management of these lesions. Despite the abundant literature regarding this topic there are few articles referring to long-term outcomes of treatment, and hardly any about Phemister technique outcomes. The purpose of this study is to evaluate the long-term radiological, functional, cosmetic and subjective results of Phemister technique for acromioclavicular injuries. Materials and methods: We retrospectively evaluated all the acromioclavicular joint injuries treated with the Phemister technique from january 1996 to december 1996. Radiographic analysis was based on five parameters: width of acromioclavicular joint, coracoclavicular interspace, variation of coracoclavicular interspace, elevation of the lateral end of the clavicle and percentage of elevation of the lateral end of the clavicle respecting the opposite acromioclavicular joint. Functional evaluation was performed with the Imatani scoring scale. Cosmetic results were analyzed considering the elevation of the lateral end of the clavicle and the aspect of the scar. Analog scale was used for rating overall patient satisfaction. Results and conclusions: Radiological results were very good in the immediate postoperative evaluation, but there was 66% incidence of recurrent acromioclavicular dislocation at a mean of 9 years follow-up. Only 66% of the patients obtained a satisfactory functional result. Cosmetic alterations at 9 years happened in 66% of the patients, including prominent lateral end of the clavicle and hypertrophic scar. Nevertheless the overall patient satisfaction was very good