Are Anterior Plates More Effective than Iliosacral Screws to Fix the Sacroiliac Joint? Biomechanical Study.

Introduction Sacroiliac joint dislocations are caused by high energy trauma and commonly treated with the iliosacral screw fixation or the anterior plating of the sacroiliac joint (SIJ). However, there is a lack of consensus regarding which procedure is the most successful in treating sacroiliac joint dislocations. This aims to compare stiffness and maximum load of pelvises with sacroiliac joint dislocations treated with both procedures in a synthetic bone model. Methods Synthetic pelvises were mounted and divided into 2 treatment groups ( n = 5): a model with two orthogonal plates placed anteriorly to the SIJ (PPS group) and another with two iliosacral screws fixating the SIJ (SPS group), both with pubic symphysis fixation. The maximum load supported by each sample was observed and the stiffness was calculated from the curve load vs displacement. The mean values of load to failure and stiffness for each group were compared with the Mann-Whitney U test ( p < 0.05 was considered significant for all analysis). Results The mean load to failure supported by the PPS group was 940 ± 75 N and the SPS was 902 ± 56 N, with no statistical difference. The SPS group showed higher values of stiffness (68.6 ± 11.1 N/mm) with statistical significant difference in comparison to the PPS sample (50 ± 4.0 N/mm). The mode of failure was different in each group tested. Conclusion Despite lower stiffness, the anterior plating fixation of the sacroiliac joint can be very useful when the iliosacral screw fixation cannot be performed. Further studies are necessary to observe any differences between these two procedures on the clinical and surgical setting.

Are Anterior Plates More Effective than Iliosacral Screws to Fix the Sacroiliac Joint? Biomechanical Study / Placas anteriores são mais efetivas do que parafusos iliossacrais na fixação da articulação sacroilíaca? Estudo Biomecânico

Abstract Introduction Sacroiliac joint dislocations are caused by high energy trauma and commonly treated with the iliosacral screw fixation or the anterior plating of the sacroiliac joint (SIJ). However, there is a lack of consensus regarding which procedure is the most successful in treating sacroiliac joint dislocations. This aims to compare stiffness and maximum load of pelvises with sacroiliac joint dislocations treated with both procedures in a synthetic bone model. Methods Synthetic pelvises were mounted and divided into 2 treatment groups (n= 5): a model with two orthogonal plates placed anteriorly to the SIJ (PPS group) and another with two iliosacral screws fixating the SIJ (SPS group), both with pubic symphysis fixation. The maximum load supported by each sample was observed and the stiffness was calculated from the curve load vs displacement. The mean values of load to failure and stiffness for each group were compared with the Mann-Whitney U test (p< 0.05 was considered significant for all analysis). Results The mean load to failure supported by the PPS group was 940 ± 75 N and the SPS was 902 ± 56 N, with no statistical difference. The SPS group showed higher values of stiffness (68.6 ± 11.1 N/mm) with statistical significant difference in comparison to the PPS sample (50 ± 4.0 N/mm). The mode of failure was different in each group tested. Conclusion Despite lower stiffness, the anterior plating fixation of the sacroiliac joint can be very useful when the iliosacral screw fixation cannot be performed. Further studies are necessary to observe any differences between these two procedures on the clinical and surgical setting.

Resumo Introdução Usualmente, as luxações sacroilíacas são tratadas com parafusos iliossacrais ou com placas anteriores à articulação sacroilíaca (ASI). Este estudo compara a rigidez e carga máxima suportada pelos dois tipos de fixações acima citados, utilizando pelves sintéticas. Método Dez pelves sintéticas foram divididas em dois grupos (n= 5). No grupo denominado PlaCF, a ASI foi fixada com duas placas anteriores. No grupo ParCF, a ASI foi fixada com dois parafusos iliossacrais no corpo da primeira vertebra sacral (S1). A rigidez e carga máxima suportada por cada montagem realizada, foi mensurada. A análise estatística foi realizada através do teste U de Mann-Whitney (p< 0.05 foi considerado estatisticamente significativo para todas as análises). Resultados A carga máxima suportada até a falha da fixação pelos grupos PlaCF e ParCF foram respectivamente 940 ± 75 N e 902 ± 56 N, não havendo diferença estatística entre eles. A rigidez obtida pelo grupo ParCF foi maior e com diferença estatística em relação ao grupo PlaCF (68.6 ± 11.1 N/mm e 50 ± 4.0 N/mm respectivamente). Conclusão Apesar da menor rigidez obtida no grupo PlaCF, as placas anteriores à ASI podem ser uma ótima opção no tratamento da luxação sacroilíaca quando os parafusos iliossacrais não puderem ser utilizados. Outros estudos são necessários para detectar possíveis diferenças entre os dois procedimentos do ponto vista cirúrgico e clínico.

Marginal impaction in posterior wall fractures of the acetabulum.

OBJECTIVE: The purposes of this study were to describe the CT features of isolated posterior acetabular wall fractures with associated marginal impaction and to discuss the potential therapeutic implications of recognizing this type of fracture. CONCLUSION: Marginal impaction is an important cause of articular incongruity that adversely affects prognosis. Radiologists should be capable of identifying posterior acetabular wall fracture patterns because they may be the first to suggest diagnoses.

Parafusos iliosacrais são realmente seguros? / Are iliosacral screws really safe?

OBJETIVO: Avaliar a segurança do uso de fixação iliosacral com parafusos em pacientes com lesão do anel pélvico. MÉTODOS: Trata-se de um trabalho restrospectivo analisando por tomografia computadorizada a topografia de 60 parafusos inseridos em 46 pacientes portadores de lesões do anel pélvico e operados no INTO-RJ, no período de 2006 e 2010. RESULTADOS: Em 21,7 por cento dos casos o parafuso encontrava-se fora do corredor de segurança descrito em literatura. Destes, 77 por cento estavam associados a uma redução insatisfatória do anel pélvico. Não houve casos de lesão neurovascular em nossa série. CONCLUSÃO: O uso de parafusos ílio-sacrais é uma técnica segura, pois mesmo em casos onde o parafuso não respeitou uma topografia ideal, não houve complicações significativas associadas a este método. A má redução do anel pélvico é um fator muito importante associado ao mau posicionamento dos parafusos.

OBJECTIVE: To evaluate the safety of iliosacral screw fixation in pelvic injuries. METHODS: A retrospective study based on computer tomography evaluation of screw topography and its relationship with the so called pelvic safe corridor. RESULTS: We evaluated the topography of 60 screws inserted in 46 patients sustaining pelvic injuries which were operated in the INTO from 2006 to 2010. In 21.7 percent of cases the screw was located outside the safe corridor. 77 percent of these misplaced screws were associated with an unsatisfactory reduction of the pelvic injury. CONCLUSIONS: In our study, a significant rate of misplaced screws in relationship with the safe corridor has been pointed out and in most of these cases an insufficient reduction of the pelvis was also identified. We conclude that iliosacral fixation is a safe adjuvant method for pelvic fixation since in our series even with a relative high incidence of misplacements, no neurovascular injuries have been recorded in association with this technique.

EPIDEMIOLOGY OF ACETABULUM FRACTURES TREATED AT THE INSTITUTO NACIONAL DE TRAUMATOLOGIA E ORTOPEDIA (INTO).

OBJECTIVES: The purpose of this study was to review the epidemiological aspects of displacement fractures of the acetabulum that had been treated surgically at the National Institute of Traumatology and Orthopedics (INTO). METHODS: We retrospectively analyzed 126 acetabulum fractures that had been treated surgically at INTO between March 2006 and November 2008. The following factors were taken into account: age, sex, trauma mechanism, injury classification, time elapsed between trauma and surgery, affected side and associated bone injuries. RESULTS: 76.8% were male; the mean age was 39.6 years. The trauma mechanism was traffic accidents in 59%; the time that elapsed between injury and surgery was on average 16.4 days; 55% of the cases were on the right side; 30% of the patients presented associated fractures. CONCLUSION: Most of the patients were male, in an economically active age group, and were victims of traffic accidents. Edge and/or posterior column fractures were the most frequent types. Associated injuries were common and most of the fractures operated in our service came to us late.

SURGICAL TREATMENT OF UNSTABLE PELVIC RING FRACTURE IN SKELETALLY IMMATURE PATIENTS.

OBJECTIVES: To present the outcomes from definitive surgical treatment for unstable fractures of the pelvic ring in children undergoing surgical reduction and stabilization. METHODS: We studied 10 patients with immature skeletons who suffered unstable fractures of the pelvic ring and were treated between March 2004 and January 2008. The study was retrospective, based on clinical and radiographic evaluations. RESULTS: The mean age at the time of the trauma was 8.8 years (2 to 13 years). Seven patients were female and three was male. There were eight cases of trauma caused by being run over, and one case each of a motorcycle accident and falling from a height. Five patients had other associated injuries such as fractures of the clavicle, femoral diaphysis, proximal humerus, lower leg bones, olecranon and bladder injury. All the patients evaluated showed an excellent clinical outcome. The pelvic asymmetry before surgery ranged from 0.7 to 2.9 cm (mean 1.45 cm), and dropped to values between 0.2 and 0.9 cm (mean 0.39 cm) after reduction. In no case was any change observed in pelvic asymmetry measured in the immediate postoperative period and at the end of follow-up. CONCLUSION: Pelvic ring fractures in skeletally immature patients are rare and surgical treatment is unusual. Several authors have questioned conservative treatment because of the complications encountered. Bone remodeling does not seem enough to cause an improvement in pelvic asymmetry, and this justifies the choice of surgical treatment for reduction and correction of pelvic ring deformities.

Tratamento cirúrgico da fratura instável do anel pélvico em pacientes esqueleticamente imaturos / Surgical treatment of unstable pelvic ring fracture in skeletally immature patients

OBJETIVO: Apresentar o resultado do tratamento cirúrgico definitivo da fratura instável do anel pélvico na criança submetida a redução e estabilização cirúrgica. MÉTODOS: Avaliamos 10 pacientes com esqueleto imaturo que sofreram fraturas instáveis do anel pélvico tratados cirurgicamente no período entre março de 2004 a janeiro de 2008. O estudo foi retrospectivo, baseado na avaliação clínica e radiográfica. RESULTADOS: A média etária na época do trauma foi de 8,8 anos (dois a 13 anos), sendo sete do sexo feminino e três do sexo masculino. As causas dos traumas foram atropelamento em oito casos, e acidente com motocicleta e queda de altura em um caso cada. Cinco pacientes apresentavam lesões associadas, como fraturas da clavícula, diáfise do fêmur, úmero proximal, ossos da perna, olecrânio e lesão de bexiga. Todos os pacientes avaliados apresentaram excelente evolução clínica. A assimetria pélvica antes do procedimento cirúrgico variava de 0,7 a 2,9cm (média 1,45cm), e caiu para valores entre 0,2 a 0,9cm (média 0,39cm) após a redução. Em nenhum dos casos houve alteração da assimetria pélvica medida no pós-operatório imediato e no fim do seguimento. CONCLUSÃO: A fratura do anel pélvico em pacientes esqueleticamente imaturos é rara e a indicação de tratamento cirúrgico não é usual. Diversos autores questionam o tratamento conservador devido às complicações encontradas. A remodelação óssea não parece suficiente para que ocorra uma melhora da assimetria pélvica, fator que justifica a opção pelo tratamento cirúrgico para a redução e correção das deformidades do anel pélvico.

OBJECTIVES: To present the outcome of the definitive surgical treatment of unstable fracture of the pelvic ring in children submitted to surgical reduction and stabilization. METHODS: We studied 10 patients with immature skeletons that suffered unstable fractures of the pelvic ring treated during the period between March 2004 and January 2008. The study was retrospective, based on clinical and radiographic evaluations. RESULTS: The mean age at the time of trauma was 8.8 years (2 to 13 years). Seven patients were female and three male. The cause of the trauma was being run over in eight cases, and one case each of a motorcycle accident and falling from a height. Five patients had other associated injuries such as fractures of the clavicle, femur diaphysis, proximal humerus, fibula, olecranon, and bladder injury. All patients showed an excellent clinical outcome. The pelvic asymmetry before surgery ranged from 0.7 to 2.9 cm (mean 1.45 cm), and dropped to values between 0.2 and 0.9 cm (mean 0.39 cm) after reduction. In no cases was a change observed in pelvic asymmetry measured in the immediate postoperative period and at the end of follow-up. CONCLUSION: Pelvic ring fractures in skeletally immature patients is rare and surgical treatment is not usual. Several authors have questioned conservative treatment due to the complications encountered. Bone remodeling is not enough to improve pelvic asymmetry, a factor that justifies the choice of surgical treatment for the reduction and correction of pelvic ring deformities.

Epidemiologia das fraturas de acetábulo tratadas no instituto nacional de traumatologia e ortopedia (Into) / Epidemiology of acetabulum fractures treated at the instituto nacional de traumatologia e ortopedia (Into)

OBJETIVOS: O propósito do presente estudo é revisar aspectos epidemiológicos das fraturas desviadas do acetábulo tratadas cirurgicamente no Instituto Nacional de Ortopedia e Traumatologia (INTO). MÉTODOS: Analisamos, retrospectivamente, 126 fraturas de acetábulo tratadas cirurgicamente no INTO, no período de março de 2006 a novembro de 2008. Levamos em consideração: idade; sexo; mecanismo de trauma; classificação da lesão; tempo decorrido entre o trauma e o tratamento cirúrgico; lado acometido; lesões ósseas associadas. RESULTADOS: 76,8 por cento são do sexo masculino, a média da idade foi de 39,6 anos; quanto ao mecanismo de trauma, 59 por cento foram por acidente automobilístico; o tempo decorrido entre a lesão e o tratamento cirúrgico foi em média 16,4 dias; 55 por cento casos foram do lado direito; 30 por cento pacientes apresentavam fraturas associadas. CONCLUSÃO: A maior parte dos pacientes é do sexo masculino, na faixa etária economicamente ativa, e vítima de acidente de trânsito, sendo as fraturas da reborda e/ou coluna posterior as mais frequentes. Lesões associadas são comuns e a maior parte das fraturas operadas em nosso serviço é envelhecida.

OBJECTIVES: The purpose of this study is to review epidemiological aspects of displacement fractures of the acetabulum treated surgically at the Instituto Nacional de Traumatologia e Ortopoedia (INTO). METHODS: We retrospectively analyzed 126 acetabulum fractures treated surgically at the INTO in the period from March 2006 to November 2008. The following elements were taken in account: age, sex, mechanism of injury, classification, time elapsed between trauma and surgery, affected side, associated bone injuries. RESULTS: 76.8 percent were male, the mean age was 39.6 years. 59 percent of the traumas were due to traffic accidents; time between injury and surgery was on average 16.4 days; 55 percent of cases were on the right side; 30 percent of patients had associated fractures. CONCLUSION: Most patients are male, in an economically active age group, and are victims of traffic accidents. Fractures of edge and/or posterior column are the most frequent. Associated injuries are common and most of the fractures operated in our service are delayed.

Avaliação Tomográfica de Fraturas Acetabulares no Pós-Operatório / Tomographic Evaluation Of Acetabular Fractures On Post Operative Period

Os autores apresentam estudo retrospectivo e analítico de 13 pacientes submetidos a tratamento cirúrgico de fratura do rebordo posterior do acetábulo pela equipe de pelve e acetábulo do INTO, no período entre junho de 2004 até março de 2006, no Instituto Nacional de Tráumato-Ortopedia

Fraturas Agudas Diafisárias do Úmero Tratadas com Haste Intramedular bloqueada Anterógrada

A haste intramedular bloqueada promove fixação estável das fraturas diafisárias do úmero com pequena exposição cirúrgica e permite mobilização precoce das articulações adjacentes