An Unusual Cause of Posterior Knee Pain: Mucoid Degeneration of the Anterior Cruciate Ligament - Case Report / Uma causa incomum de dor posterior no joelho: degeneração mucóide do ligamento cruzado anterior - Relato de caso

Abstract Mucoid degeneration of the anterior cruciate ligament (ACL) is an uncommon cause of pain in the posterior region of the knee, of unknown pathophysiology and underdiagnosed. The best treatment modality is still under discussion. Resection of the lesion with partial ACL debridement has shown good results without the occurrence of instability. The authors present a case of mucoid degeneration of the ACL treated with resection of the mucoid degeneration and partial debridement of the ACL by arthroscopy.

Resumo A degeneração mucoide do ligamento cruzado anterior (LCA) é uma causa pouco frequente de dor na região posterior do joelho, de patofisiologia desconhecida e subdiagnosticada. A melhor modalidade de tratamento ainda está em discussão. A ressecção da lesão com desbridamento parcial do LCA tem apresentado bons resultados, sem a ocorrência de instabilidade. Os autores apresentam um caso de degeneração mucoide do LCA tratado com ressecção da degeneração mucoide e desbridamento parcial do LCA por artroscopia.

Unusual Arteriovenous Malformation in Total Hip Arthroplasty: Case Report of a Complicated Perioperative Course / Malformação arteriovenosa incomum em artroplastia total do quadril: relato de caso de um perioperatório de curso complicado

Abstract It is not common to encounter arteriovenous malformations (AVMs) during total hip arthroplasty (THA). We report the present case to draw attention to the possibility of an AVM during the direct anterior approach (DAA) for THA, which, if not borne in mind, may lead to the myriad of complications related to excessive bleeding. An 81-year-old female presented to the emergency department with a left femoral neck fracture. She elected to undergo a THA via the DAA. Abnormal appearing blood vessels were present near the ascending circumflex branches, which provided difficulty in achieving hemostasis. Excessive blood loss was noted, and the patient received one unit of packed red blood cells during the operation. Hemoglobin and hematocrit dropped in the days following surgery, requiring several additional transfusions of blood products. When the patient complained of progressive left leg swelling on postoperative day 3, a computed tomography revealed large hematomas within the left adductors and the left iliopsoas muscle. Active extravasation was identified arising from a branch of the left profunda femoral artery, as well as an arteriovenous fistula (AVF) in this area. Bleeding was controlled by selective endovascular coil embolization. As of current knowledge, this is the first reported intraoperative discovery of congenital arteriovenous malformation (AVM) with subsequent development of postoperative arteriovenous fistula and associated symptomatic hematomas in the setting of THA using the DAA. Early recognition and intervention of vascular malformations is essential in preventing potential limb- or life-threatening surgical complication.

Resumo Não é comum encontrar malformações arteriovenosas (MAV) durante a artroplastia total do quadril (ATQ). Relatamos o presente caso para chamar a atenção para a possibilidade de uma MAV durante a abordagem anterior direta (AAD) para ATQ, que se não for considerada, pode levar a uma miríade de complicações relacionadas ao sangramento excessivo. Uma mulher de 81 anos foi apresentada ao pronto-socorro com fratura no pescoço do fêmur esquerdo. Ela optou por se submeter a uma artroplastia total do quadril (ATQ) através da AAD. Vasos sanguíneos aparentemente anormais estavam presentes perto dos ramos circunflexos ascendentes, proporcionando dificuldade em alcançar hemostasia. A perda excessiva de sangue foi notada e a paciente recebeu uma unidade de glóbulos vermelhos embalados durante a operação. Hemoglobina e hematócrito caíram nos dias seguintes à cirurgia, exigindo várias transfusões adicionais de produtos sanguíneos. Quando a paciente reclamou de inchaço progressivo na perna esquerda no terceiro dia pós-operatório, a tomografia computadorizada revelou hematomas grandes dentro dos adutores esquerdos e do músculo iliopsoas esquerdo. A extravasão ativa foi identificada a partir de um ramo da artéria femoral esquerda, bem como de uma fístula arteriovenosa (FAV) nesta área. O sangramento foi controlado por embolização seletiva da bobina endovascular. A partir do conhecimento atual, esta é a primeira descoberta intraoperatória relatada de MAC congênita com desenvolvimento subsequente de FAV pós-operatória e hematomas sintomáticos associados no cenário de ATQ utilizando a AAD. O reconhecimento precoce e a intervenção de malformações vasculares são essenciais para prevenir possíveis complicações cirúrgicas de membros ou de risco de vida.

Comparison of Surgical Procedures in the Treatment of Hip Periprosthetic Infection / Comparação entre procedimentos cirúrgicos no tratamento da infecção de prótese do quadril

Abstract Objective The present study aimed to compare the cure rate recovery time and Merle d'Aubigné-Postel functional (MAPF) score after single-stage surgery (C1T) or two-stage surgery (C2T) to treat prosthetic infections of the hip considering sociodemographic and clinical features of the patients. Materials and Methods The present retrospective study occurred in a single center from 2011 to 2014 with 37 studied cases including 26 treated with C1T and 11 with C2T. We compared the cure rate recovery time and MAPF score in the two groups as well as the sociodemographic and clinical features of the patients. We also considered surgical complications and the most common infectious agents. Results The C1T group had a faster functional recovery than the C2T group but there were no significant differences in the cure rate surgical complications or MAPF score. However C1T group patients were significantly younger which may have influenced the outcomes. Staphylococcus spp. was the most common infectious agent (62%). Conclusion Although C2T appears superior regarding infection cure C1T may be preferable for faster functional recovery. However it is critical to consider individual patient characteristics when choosing treatment. Further research with a larger sample size is required to confirm these results.

Resumo Objetivo Comparar a taxa de cura, o tempo de recuperação e a pontuação na escala funcional de Merle d'Aubigné-Postel (EFMA) entre a cirurgia em tempo único (C1T) e a cirurgia em dois tempos (C2T) no tratamento de infecções protéticas do quadril, considerando as características sociodemográficas e clínicas dos pacientes. Materiais e Métodos Foi realizado um estudo retrospectivo num único centro, entre 2011 e 2014, com um total de 37 casos estudados, sendo 26 tratados com C1T e 11 com C2T. Foram comparadas a taxa de cura, o tempo de recuperação e a pontuação EFMA entre os dois grupos, bem como as características sociodemográficas e clínicas dos pacientes. Foram também consideradas as complicações cirúrgicas e o agente infeccioso mais comum. Resultados O grupo C1T teve uma recuperação funcional mais rápida do que o grupo C2T, mas não houve diferenças significativas na taxa de cura, nas complicações cirúrgicas ou na pontuação EFMA. No entanto, o grupo C1T era significativamente mais jovem, o que pode ter influenciado os resultados. Staphylococcus spp. foi o agente infeccioso mais comum (62%). Conclusão Embora a C2T pareça ser superior em termos de cura de infecção, a C1T pode ser preferível para uma recuperação funcional mais rápida. No entanto, as características individuais dos pacientes devem ser consideradas na escolha do tratamento. São necessárias mais pesquisas com um tamanho de amostra maior para confirmar estes resultados.

Fijación interna combinada con artroplastia total de cadera en fracturas acetabulares inveteradas complejas en ancianos. Reporte de caso / Internal fixation combined with total hip arthroplasty in complex inveterate acetabular fractures in the elderly. Case report

La fijación interna combinada con artroplastia en pacientes de edad avanzada, está indicada en fracturas acetabulares complejas inveteradas, artrosis preexistente, luxación inveterada, Impactación supero-medial de la cúpula acetabular, la finalidad de la cirugía es lograr la fijación de la columna anterior, columna posterior, lamina cuadrilátera y pared posterior para proporcionar estabilidad adecuada al componente acetabular y restaurar el centro de rotación de la cadera. Debido a la complejidad de estas lesiones, se decide presentar el siguiente caso clínico, que corresponde una paciente femenina de 70 años, quien posterior a traumatismo de baja energía presenta fractura inveterada compleja con patrón en T de Acetábulo de 8 meses de evolución. El Objetivo es: Evaluar los resultados del tratamiento de las fracturas acetabulares complejas en pacientes de edad avanzada con reducción abierta más fijación interna combinada con artroplastia total de cadera. Se realiza en un 1er tiempo: Abordaje Ilioinguinal, ORIF con placa de reconstrucción 3,5 mm para CA, 2do Tiempo: Abordaje de Kocher Langenbeck, ORIF con placa de reconstrucción 3,5 mm para CP y PP. 3er Tiempo: ATC izquierda primaria no cementada, con aporte biológico de injerto óseo autologo. Resultado: Se restableció la integridad de las líneas acetabulares, reducción anatómica según Matta, índice de Harris hip score de 88 puntos. Se concluye que el procedimiento combinado de ORIF mas ATC es el tratamiento ideal de las fracturas acetabulares complejas inveteradas en pacientes de edad avanzada(AU)

Internal fixation combined with arthroplasty in elderly patients is indicated in inveterate complex acetabular fractures, preexisting osteoarthritis, inveterate dislocation, supero medial impaction of the acetabular dome, the purpose of surgery is to achieve fixation of the anterior column (AC), posterior column (PC), quadrilateral plate, and posterior wall (PP) to provide adequate stability to the acetabular component and restore the hip center of rotation. Due to the complexity of these injuries, it is decided to present the following clinical case, which corresponds to a 70-year-old female patient, who, after a low-energy trauma, presents a complex inveterate fracture with a T-pattern of the acetabulum of 8 months of evolution. The Objective is: To evaluate the results of the treatment of complex acetabular fractures in elderly patients with open reduction plus internal fixation (ORIF) combined with total hip arthroplasty (THA). It is performed in a 1st stage: Ilioinguinal approach, ORIF with 3.5 mm reconstruction plate for (CA), 2nd Stage: Kocher Langenbeck approach, ORIF with 3.5 mm reconstruction plate for (CP) and (PP). 3rd Time: Uncemented primary left THA, with biological contribution of autologous bone graft. Result: The integrity of the acetabular lines was restored, anatomical reduction according to Matta, Harris hip score index of 88 points. It is concluded that the combined procedure (ORIF plus ATC) is the ideal treatment of inveterate complex acetabular fractures in elderly patients(AU)

Efficacy of Ibuprofen after Total Hip Arthroplasty to Prevent Heterotopic Ossification: Systematic Review and Meta-Analysis / Eficácia do ibuprofeno após artroplastia total de quadril para prevenção de ossificação heterotópica: Revisão sistemática e metanálise

Abstract The objective of this study was to conduct a systematic review and meta-analysis of relevant randomized control trials (RCTs) to determine the role of ibuprofen, as well as the optimum dose and duration of therapy, in preventing the incidence of heterotopic ossification (HO) after primary total hip arthroplasty (THA). A literature search was performed using the PubMed/MEDLINE and Cochrane Library databases for RCTs that compared the use of ibuprofen versus placebo as prophylaxis for HO in patients after THA. The main outcomes for this study were overall occurrence of HO, occurrence according to the Brooker classification, and gastrointestinal complications. A total of 27 potential articles were identified from the database. Eventually, four trials with 1,153 patients were included in the final analysis. When compared with placebo, the use of ibuprofen is associated with a reduction in the incidence of HO at the 3- and 12-month follow-up appointments, as well as the incidence of Brooker II and III HO (p < 0.05). However, there was no significant difference between the ibuprofen and placebo groups in terms of treatment discontinuation due to gastrointestinal complications or the incidence of Brooker I and IV HO (p > 0.05). The existing data indicates that ibuprofen is safe and efficacious in reducing the total incidence of HO along with Brooker II and III HO at follow-up. However, due to the small number of studies, the conclusions are limited; therefore, more high-quality clinical trials are required to develop guidelines for optimal dose and duration of therapy.

Resumo O objetivo deste estudo foi realizar uma revisão sistemática e metanálise de estudos clínicos randomizados (ECRs) relevantes para determinar o papel do ibuprofeno, sua dose ideal, e a duração do tratamento na prevenção de ossificação heterotópica (OH) após a artroplastia total primária do quadril (ATQ). Uma pesquisa bibliográfica foi feita nos bancos de dados PubMed/MEDLINE e Cochrane Library para a obtenção de ECRs quecomparassem ouso de ibuprofeno edeplacebo como profilaxiaparaOHem pacientes submetidos à ATQ. Os principais desfechos deste estudo foram ocorrência geral de OH, classificação de Brooker da OH, e complicações gastrintestinais. No total, 27 artigos foram identificados nos bancos de dados e 4 estudos, com 1.153 pacientes, foram incluídos na análise final. Em comparação ao placebo, o uso de ibuprofeno reduziu a incidência de OH aos 3 e 12 meses de acompanhamento e a incidência de OH Brooker II e III (p < 0,05). No entanto, não houve diferença significativa entre os grupos que receberam ibuprofeno e placebo em termos de interrupção do tratamento devido a complicações gastrintestinais ou da incidência de OH Brooker I e IV (p > 0,05). Os dados existentes indicam que o ibuprofeno é seguro e eficaz na redução da incidência total de OH e de OH Brooker II e III durante o acompanhamento. No entanto, as conclusões são limitadas devido ao pequeno número de estudos; logo, mais estudos clínicos de alta qualidade são necessários para o desenvolvimento de diretrizes em relação à dose e duração ideal da terapia.

Biomechanical Gait Analysis in Patients with Osteonecrosis of the Femoral Head / Análise biomecánica da marcha de pacientes com osteonecrose da cabeça do fémur

Abstract Objectives Although osteonecrosis of the femoral head is a prevalent condition, its effects on gait parameters have not been thoroughly studied and are not well-established in the current literature. The primary aim of the present study is to describe gait in patients with a diagnosis of osteonecrosis. Methods This is a cross-sectional study. Nine patients diagnosed with osteonecrosis of the femoral head who were regularly followed-up at an outpatient clinic were selected for the present study and underwent gait analysis using Vicon Motion Capture Systems. Spatiotemporal data was obtained, and joint angles were calculated using an Euler angle coordinate system. Distal coordinate systems were used to calculate joint momentsand forceplatestoobtaingroundreactionforces. Results Patients with osteonecrosis presented with slower velocity (0.54 m/s ± 0.19) and smaller cadence (83.01 steps/min ± 13.23) than healthy patients. The pelvic obliquity range of motion was of 10.12° ± 3.03 and rotation was of 18.23° ± 9.17. The mean hip flexion was of 9.48° ± 3.40. Ground reaction forces showed reduced braking and propelling forces. Joint moments were reduced for flexion and adduction (0.42 Nm/kg ± 0.2 and 0.30 Nm/kg ± 0.11, respectively) but the abduction moment was increased (0.42 Nm/kg ± 0.18). Conclusions The present study showed that osteonecrosis of the femoral head presents compensatory gait mechanisms, with increased pelvic motion and decreased knee flexion to protect the hip joint. Decreased moments for hip flexion and adduction were also identified and muscle weakness for those groups may be correlated to the disease.

Resumo Objetivos Embora a osteonecrose da cabeça do fêmur seja uma lesão prevalente, seus efeitos sobre os parâmetros da marcha não foram minuciosamente estudados e não estão bem estabelecidos na literatura atual. O objetivo principal do presente estudo é descrever a marcha em pacientes com osteonecrose. Métodos Trata-se de um estudo transversal. Nove pacientes com diagnóstico de osteonecrose da cabeça do fêmur, sob acompanhamento regular em ambulatório, foram selecionados para o presente estudo e submetidos à análise da marcha com Vicon Motion Capture Systems. Os dados espaciais e temporais foram obtidos e os ângulos articulares foram calculados com o sistema de coordenadas angulares de Euler. Sistemas de coordenadas distais e plataformas de força foram utilizados para o cálculo de momentos articulares e de forças de reação ao solo, respectivamente. Resultados Os pacientes com osteonecrose apresentaram menor velocidade (0,54 m/s ± 0,19) e menor cadência (83,01 passos/minuto ± 13,23) do que pacientes saudáveis. As amplitudes de movimento de obliquidade e rotação pélvica foram de 10,12°± 3,03 e 18,23° ± 9,17, respectivamente. A média de flexão do quadril foi de 9,48° ± 3,40. O estudo das forças de reação ao solo revelou redução das forças de frenagem e propulsão. Os momentos articulares de flexão e adução caíram (0,42 Nm/kg ± 0,2 e 0,30 Nm/kg ± 0,11), mas o momento de abdução aumentou (0,42 Nm/kg ± 0,18). Conclusões O presente estudo mostrou que a osteonecrose da cabeça do fêmur é associada a mecanismos compensatórios da marcha, com aumento da movimentação pélvica e diminuição da flexão do joelho para proteção da articulação do quadril. A redução dos momentos de flexão e adução do quadril também foi identificada e a fraqueza destes grupos musculares pode estar correlacionada à doença.

Osseointegration and Success in Hip Arthroplasty Acetabular Revision Using Structured Homologous Graft Average 9.6 Years Follow-up / Osteointegração e sucesso em revisão acetabular de artroplastia total de quadril com enxerto estrutural homólogo seguimento médio de 9, 6 anos

Abstract Objective To evaluate the clinical and radiographic results and survival of the acetabular revision surgery of total hip arthroplasty with cemented implant without the use of reinforcement ring, associated with structural homologous bone grafting. Methods A total of 40 patients (44 hips) operated from 1995 to 2015 were retrospectively analyzed. Radiographs were evaluated according to the classification of the acetabular bone defect, graft shape, and the presence of osseointegration. Cases were considered as failures when the migration of the implant was > 5 mm in any direction, and/or the progression of radiolucency lines around the acetabular component were > 2 mm. We verified the association of radiographic findings with cases of failure using statistical tests and analyzed survival using the Kaplan-Meier curve. Results Of the 44 hips, 45.5% of the acetabular defects were Paprosky type 3A and 50% were 3B. In 65% of the hips, the graft configuration was classified as Prieto type 1 and in 31% as type 2. No radiographic evidence of osseointegration was observed in 13.6% of the cases. We observed 9 (20.5%) reconstruction failures. A correlation was observed between reconstruction failure and the absence of radiographic signs of graft osseointegration. Conclusion We observed good clinic and radiographic results, with survival of 79.54% in a mean follow-up of 9.65 years. Also, there was an association between absence of radiographic signs of osseointegration of the structural graft and failure in this series of patients with large bone defects. The failures did not correlate with the severity of the acetabular bone defect, thickness, or graft configuration.

Resumo Objetivo Avaliarosresultadosclínicos, radiográficos e a sobrevida da cirurgia de revisão acetabular de artroplastia total de quadril com implante cimentado sem uso de anel de reforço, associado à enxertia óssea homóloga estrutural. Métodos Um total de 40 pacientes (44 quadris) operados de 1995 a 2015 foram analisados retrospectivamente. As radiografias foram avaliadas de acordo com a classificação do defeito ósseo acetabular, o formato do enxerto e à presença de osteointegração. Foram considerados casos de insucesso a migração do implante > 5 mm em qualquer direção e/ou a progressão de linhas de radioluscência em torno do componente acetabular > 2mm. Verificamos a associação dos achados radiográficos com os casos de falha utilizando testes estatísticos e analisamos a sobrevida utilizando a curva de Kaplan-Meier. Resultados Dos 44 quadris, 45,5% dos defeitos acetabulares eram Paprosky tipo 3A e 50%, 3B. Em 65% dos quadris, a configuração do enxerto foi classificada como tipo 1 de Prieto e em 31% como tipo 2. Não foi observada evidência radiográfica de osteointe-gração em 13,6% dos casos. Observamos 9 (20,5%) falhas de reconstrução. Foi observada correlação entre falha da reconstrução com a ausência de sinais radiográficos de osteointegração do enxerto. Conclusão Observamos bons resultados clínicos e radiográficos, com sobrevida de 79,54% em seguimento médio de 9,65 anos. Também houve associação entre ausência de sinais radiográficos de osteointegração do enxerto estrutural e falha nesta série de pacientes com grandes defeitos ósseos. As falhas não se correlacionaram com a severidade do defeito ósseo acetabular, espessura ou configuraçãodoenxerto.

Perception of Patients on the Waiting List for Total Hip Arthroplasty on the Resumption of Elective Surgeries during the COVID-19 Pandemic / Percepção dos pacientes em lista de espera para artroplastia total do quadril sobre a retomada das cirurgias eletivas durante a pandemia COVID-19

Abstract Objective To analyze the profile and perception ofpatients on the waiting list for total hip arthroplasty (THA) about performing elective surgeries during the COVID-19 pandemic. Methods From July to November 2021, patients on the THA waiting list were interviewed during outpatient consultations. To compare the groups regarding categorical variables, the Chi-square test or Fisher's exact test was applied, and for quantitative variables the Mann-Whitney test was applied. The results were calculated using the Statistica program version 7. Results 39 patients answered the questionnaire. The mean age was 58.95 years, with 53.85% male. Approximately 60% expressed concern about contracting or transmitting COVID-19 to their family members after hospitalization for THA. 58.9% of patients felt hampered by the delay in scheduling elective surgeries during the pandemic. 23% lost or had a family member who lost their job during the pandemic, with a statistical difference for the group under 60 years old (p = 0.04). Conclusion Most patients were concerned about becoming infected and exposing family members to COVID-19 after surgery and noted damage due to suspensions and delay in scheduling elective surgeries. The economic impact of the pandemic was revealed by the rate of 23% of respondents who lost or had a family member who lost their job during the pandemic, being higher in patients under 60 years of age (p = 0.04).

Resumo Objetivo Analisar o perfil e a percepção dos pacientes em lista de espera para artroplastia total do quadril (ATQ) sobre a realização das cirurgias eletivas durante a pandemia pela COVID-19. Métodos De julho a novembro de 2021, foram entrevistados pacientes em lista de espera para ATQ durante consultas ambulatoriais. Para comparar os grupos com relação às variáveis categóricas foi aplicado o Teste Qui-quadrado ou Teste exato de Fisher e para as variáveis quantitativas foi aplicado o teste de Mann-Whitney. Os resultados foram calculados utilizando o programa Statistica versão 7. Resultados 39 pacientes responderam ao questionário. A média de idade foi de 58,95 anos, sendo 53,85% do sexo masculino. Aproximadamente, 60% manifestaram preocupação em contrair ou transmitir COVID-19 aos seus familiares após internação hospitalar para ATQ. 58,9% dos pacientes sentiram-se prejudicados pelo atraso no agendamento das cirurgias eletivas durante a pandemia. 23% perderam ou tiveram algum familiar que perdeu o emprego durante a pandemia, havendo diferença estatística para o grupo com menos de 60 anos (p = 0,04). Conclusão A maioria dos pacientes sentiram preocupação em infectar-se e expor familiares à COVID-19 após a cirurgia e notaram prejuízo pelas suspensões e atraso no agendamento de cirurgias eletivas. O impacto econômico da pandemia revelou-se pela taxa de 23% de entrevistados que perderam ou tiveram algum familiar que perdeu seu emprego durante a pandemia, sendo maior nos pacientes menores de 60 anos (p = 0,04).

Reproducibility of Digital Planning in Cementless Total Hip Arthroplasty Among Experienced and Novice Surgeons / Reprodutibilidade do planejamento digital na artroplastia total do quadril sem cimento entre cirurgiões experientes e iniciantes

Abstract Objective The present study aims to assess the reproducibility of digital planning for cementless total hip arthroplasty (THA) among surgeons with different levels of experience. In addition, it attempts to determine the degree of planning reliability based on a contralateral THA or on a spherical marker positioned at the greater trochanter for calibration. Methods Two evaluators with different experience levels (A1 and A2) performed independently the retrospective digital surgical planning of 64 cementless THAs. Next, we compared the planning with the implants used in the surgery. The reproducibility was excellent when planning and implants were identical; proper in case of a single-unit variation; and inappropriate if there was variation in two or more units. The present analysis also determined the calibration accuracy between the contralateral THA and the spherical marker at the greater trochanter level. Results The present study demonstrated greater success when the most experienced evaluator performed the planning and greater accuracy for the contralateral THA. When splitting the analysis per parameter (contralateral THA or spherical marker), there was a statistical difference only for the planning of A1 and the implants used in the surgery. This difference occurred in the excellent category, with 67.3% for contralateral THA compared with 30.6% for a spherical marker (p < 0.001), and in the inappropriate category, with 7.1% for contralateral THA compared with 30.6% for a spherical marker (p < 0.001). Conclusions Digital planning is more accurate when performed by an experienced evaluator. The contralateral prosthesis head was a better reference than a marker on the greater trochanter.

Resumo Objetivo Avaliar a reprodutibilidade do planejamento digital da artroplastia total de quadril (ATQ) sem cimento entre cirurgiões com diferentes níveis de experiência e o grau de confiabilidade no planejamento baseado na ATQ contralateral com o método de marcador esférico posicionado ao nível do trocanter maior. Método Dois avaliadores com níveis de experiência diferentes (A1 e A2) realizaram de forma independente o planejamento digital operatório retrospectivo de 64 ATQs sem cimento. O planejamento foi comparado com os implantes utilizados na cirurgia, sendo classificados como: excelentes, quando idênticos; adequados, quando houve variação de uma unidade; e inadequados, quando ocorreu variação de duas ou mais unidades. Na presente análise, também foi avaliada a acurácia do parâmetro de calibragem entre a ATQ contralateral comparada com o marcador esférico ao nível do trocanter maior. Resultados O estudo demonstrou maior êxito no planejamento quando realizado pelo avaliador mais experiente, com maior acurácia na ATQ contralateral. Ao fragmentar a análise de acordo com o parâmetro utilizado (ATQ contralateral ou marcador esférico), houve diferença estatística apenas na comparação do planejamento do avaliador A1 com os implantes utilizados na cirurgia. Esta diferença ocorreu na classificação excelente com 67,3% em ATQ contralateral como parâmetro contra 30,6% com marcador esférico (p < 0,001) e inadequado de 7,1% contra 30,6%, respectivamente (p < 0,001). Conclusões A acurácia do planejamento digital é mais precisa quando realizada por um avaliador experiente e a utilização da cabeça de prótese contralateral como referência se mostrou superior à utilização de um marcador no trocanter maior.

The Efficacy of Topical Tranexamic Acid in Femoral Neck Fractured Patients Undergoing Cemented Bipolar Hemiarthroplasty: A Randomized Double Blinded Controlled Trial / A eficácia do ácido tranexâmico tópico em pacientes com fraturas no pescoço femoral submetidos a hemiartroplastia bipolar cimentada: Um ensaio controlado duplo-cego randomizado

Abstract Objective Tranexamic acid (TXA) is an antifibrinolytic that is widely used for decreasing blood loss and blood transfusion rates in total hip arthroplasty. However, there is limited evidence of topical TXA usage in hip hemiarthroplasty for femoral neck fractures. The present study aimed to evaluate the effects of topical TXA on blood loss and on blood transfusions in femoral neck fracture patients who underwent cemented bipolar hemiarthroplasty. Methods Twenty-six patients with femoral neck fractures who were scheduled for bipolar cemented arthroplasty were randomized into two groups. The first group of 12 patients received topical TXA during their operation, whereas 14 patients in the second group received a placebo. Hematocrit was measured at 6 and 24 hours postoperatively. Blood transfusions and postoperative complications were also recorded. Results Total blood loss was not different between the TXA group and the control group (TXA group: 459.48 ± 456.32 ml, and control group: 732.98 ± 474.02 ml; p = 0.14). However, there were no patients within the TXA group who required a blood transfusion, while there were 4 patients in the control group who received allogenic blood transfusions (p = 0.044). There were no postoperative complications, such as wound complication, venous thromboembolism, or cardiovascular complications within either group. Conclusion Topical TXA could not decrease total blood loss but was able to reduce transfusion rates in patients who underwent cemented bipolar hip hemiarthroplasty in femoral neck fractures. Further studies in doses of topical TXA in a larger sample size would be beneficial. Level of Evidence II.

Resumo Objetivo O ácido tranexâmico (TXA) é um antifibrinolítico amplamente utilizado para diminuir as taxas de perda de sangue e de transfusão de sangue na artroplastia total do quadril. No entanto, há evidências limitadas de uso tópico de TXA na hemiartroplastia do quadril para fraturas no pescoço femoral. O presente estudo teve como objetivo avaliar os efeitos do TXA tópico na perda de sangue e transfusões de sangue em pacientes com fratura femoral que foram submetidos a hemiartroplastia bipolar cimentada. Métodos Vinte e seis pacientes com fraturas no pescoço femoral e programados para artroplastia cimentada bipolar foram randomizados em dois grupos. O primeiro grupo de 12 pacientes recebeu TXA tópico durante a operação; no segundo grupo, 14 pacientes receberam placebo. O hematócrito foi medido às 6 e 24 horas no pósoperatório. Também foram registradas transfusões de sangue e complicações pósoperatórias. Resultados A perda total de sangue não foi diferente entre o grupo TXA e o grupo controle (grupo TXA: 459,48 ±456,32 ml; e grupo controle: 732,98 ±474,02 ml; p = 0,14). No entanto, não houve pacientes dentro do grupo TXA que necessitaram de transfusão de sangue, enquanto 4 pacientes no grupo controle fizeram transfusões de sangue halogênicas (p = 0,044). Não houve complicações pós-operatórias, tais como complicação da ferida, tromboembolismo venoso ou complicações cardiovasculares dentro de qualquer grupo. Conclusão O TXA tópico não conseguiu diminuir a perda total de sangue, mas foi capaz de reduzir as taxas de transfusão, em pacientes submetidos a hemiartroplastia de quadril bipolar cimentada em fraturas no pescoço femoral. Outros estudos com doses de TXA tópico em um tamanho amostral maior seriam benéficos. Nível de Evidência II.

The Effectiveness of Periarticular Anesthetic Infiltration in Postoperative Analgesia of Total Hip Arthroplasty / A eficácia da infiltração periarticular anestésica na analgesia pós-operatória de artroplastia total do quadril

Abstract Objective The present study aims to evaluate the effectiveness of the periarticular hip infiltration technique in the postoperative period of total hip arthroplasty. Methods This is a randomized double-blind controlled clinical trial in patients with femoral neck fractures or hip osteoarthritis submitted to a total hip arthroplasty at our institution. The periarticular infiltration technique consisted of the administration of an anesthetic (levobupivacaine) and a steroid (dexamethasone) agent in the nociceptor-rich tissues of the hip after orthopedic implants placement. The control group received an injection of 0.9% saline into the same tissues. Pain, range of motion, and use of opioid analgesic agents after 24 and 48hours of the procedure were evaluated, as well as the presence of adverse effects, time to resume walking, and total hospitalization time. Results The study evaluated 34 patients. The experimental group required fewer opioid agents between 24 and 48 hours. The reduction in pain scores was greater in the placebo group. Conclusion Periarticular anesthetic infiltration as a method of postoperative analgesia for total hip arthroplasty reduced the rates of opioid intake between 24 and 48hours. It provided no benefits regarding pain, mobility, length of stay, or complications.

Resumo Objetivo Este estudo tem como objetivo avaliar a eficácia da técnica de infiltração periarticular do quadril no pós-operatório de artroplastia total do quadril. Métodos Estudo clínico randomizado duplo-cego controlado. O estudo foi realizado nos pacientes com fratura de colo femoral ou osteoartrose de quadril, submetidos ao procedimento cirúrgico de artroplastia total do quadril em nossa instituição. A técnica de infiltração periarticular consistiu na aplicação da combinação de um anestésico (levobupivacaína) com um corticosteroide (dexametasona) nos tecidos ricos em nociceptores do quadril, após a colocação dos implantes ortopédicos. No grupo controle, foi realizada infiltração de soro fisiológico 0,9% nos mesmos tecidos. Após 24 e 48 horas do procedimento, foram avaliados os quesitos de dor, amplitude de movimentos, uso de analgésicos opióides, presença de efeitos adversos, período do início da deambulação e o tempo total de hospitalização. Resultados Trinta e quatro pacientes foram estatisticamente avaliados no estudo. Foi observada uma redução no consumo de opioides entre 24 e 48 h no grupo experimental. Uma redução maior da pontuação de dor foi observada no grupo placebo. Conclusão A infiltração periarticular anestésica como método de analgesia pós-operatória de artroplastia total do quadril, neste estudo, reduziu as taxas deconsumo de opioides

Effectiveness in Sterilization of Objects Produced by 3D Printing with Polylactic Acid Material: Comparison Between Autoclave and Ethylene Oxide Methods / Eficácia na esterilização de objetos produzidos pela impressão 3D com material ácido polilático: Comparação entre os métodos autoclave e óxido de etileno

Abstract Objective Due to the popularity of 3D technology, surgeons can create specific surgical guides and sterilize them in their institutions. The aim of the present study is to compare the efficacy of the autoclave and ethylene oxide (EO) sterilization methods for objects produced by 3D printing with polylactic acid (PLA) material. Methods Forty cubic-shaped objects were printed with PLA material. Twenty were solid and 20 were hollow (printed with little internal filling). Twenty objects (10 solid and 10 hollow) were sterilized in autoclave, forming Group 1. The others (10 solid and 10 hollow) were sterilized in EO, composing Group 2. After sterilization, they were stored and referred to culture. Hollow objects of both groups were broken during sowing, communicating the dead space with the culture medium. The results obtained were statistically analyzed (Fisher exact test and residue analysis). Results In group 1 (autoclave), there was bacterial growth in 50% of solid objects and in 30% of hollow objects. In group 2 (EO), growth occurred in 20% of hollow objects, with no bacterial growth in solid objects (100% of negative samples). The bacteria isolated in the positive cases was non-coagulase-producing Staphylococcus Gram positive. Conclusions Sterilization by both autoclave and EO was not effective for hollow printed objects. Solid objects sterilized by autoclave did not demonstrate 100% of negative samples and were not safe in the present assay. Complete absence of contamination occurred only with solid objects sterilized by EO, which is the combination recommended by the authors.

Resumo Objetivo Devido à popularidade da tecnologia 3D, cirurgiões podem criar guias cirúrgicos específicos e esterilizá-los nas suas instituições. O objetivo do presente estudo é comparar a eficácia dos métodos de esterilização por autoclave e óxido de etileno (OE) de objetos produzidos pela impressão 3D com material ácido polilático (PLA, na sigla em inglês). Métodos Quarenta objetos em formato cúbico foram impressos com material de PLA. Vinte eram sólidos e 20 eram ocos (impressos com pouco enchimento interno). Vinte objetos (10 sólidos e 10 ocos) foram esterilizados em autoclave, formando o Grupo 1. Os demais (10 sólidos e 10 ocos) foram esterilizados em OE, compondo o Grupo 2. Após a esterilização, os objetos foram armazenados e encaminhados para cultura. Objetos ocos de ambos os grupos foram quebrados durante a semeadura, comunicando o espaço morto com o meio de cultura. Os resultados obtidos foram analisados estatisticamente (teste exato de Fisher e análise de resíduo). Resultados No grupo 1 (autoclave) houve crescimento bacteriano em 50% dos objetos sólidos e em 30% dos objetos ocos. No grupo 2 (OE) o crescimento ocorreu em 20% dos objetos ocos, com ausência de crescimento bacteriano nos objetos sólidos (100% de amostras negativas). A bactéria isolada nos casos positivos foi Staphylococcus Gram positivo não produtor de coagulase. Conclusões A esterilização tanto em autoclave quanto pelo OE não foi eficaz para objetos impressos no formato oco. Objetos sólidos esterilizados em autoclave não demonstraram 100% de amostras negativas, não sendo seguro no presente ensaio. Ausência completa de contaminação ocorreu apenas com objetos sólidos esterilizados pelo OE, sendo a combinação recomendada pelos autores.

The Impact of Resident Involvement on Patient Outcomes in Revision Total Hip Arthroplasty / O impacto do envolvimento do residente nos resultados dos pacientes na revisão da artroplastia total do quadril

Abstract Objective The aim of the present study was to determine the influence of resident involvement on acute complication rates in revision total hip arthroplasty (THA). Methods Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, 1,743 revision THAs were identified from 2008 to 2012; 949 of them involved a resident physician. Demographic information including gender and race, comorbidities including lung disease, heart disease and diabetes, operative time, length of stay, and acute postoperative complications within 30 days were analyzed. Results Resident involvement was not associated with a significant increase in the risk of acute complications. Total operative time demonstrated a statistically significant association with the involvement of a resident (161.35 minutes with resident present, 135.07 minutes without resident; p< 0.001). There was no evidence that resident involvement was associated with a longer hospital stay (5.61 days with resident present, 5.22 days without resident; p= 0.46). Conclusion Involvement of an orthopedic resident during revision THA does not appear to increase short-term postoperative complication rates, despite a significant increase in operative times.

Resumo Objetivo O objetivo do presente estudo foi determinar a influência do envolvimento dos residentes nas taxas de complicações agudas na revisão da artroplastia total do quadril (ATQ). Métodos Utilizando o banco de dados do American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP, na sigla em inglês), foram identificadas 1.743 revisões de ATQs entre 2008 e 2012; 949 delas envolveram um médico residente. Foram analisadas informações demográficas, incluindo gênero e raça, comorbidades, incluindo doenças pulmonares, doenças cardíacas e diabetes, tempo de permanência e complicações agudas pós-operatórias no prazo de 30 dias. Resultados O envolvimento dos residentes não foi associado a um aumento significativo no risco de complicações agudas. O tempo de operação total demonstrou associação estatisticamente significativa com o envolvimento de um residente (161,35 minutos com residente presente, 135,07 minutos sem residente; p< 0,001). Não houve evidência de que o envolvimento do residente tenha sido associado a um maior tempo de internação hospitalar (5,61 dias com residente presente, 5,22 dias sem residente; p= 0,46). Conclusão O envolvimento de um residente ortopédico durante a revisão da ATQ não parece aumentar as taxas de complicações pós-operatórias de curto prazo, apesar de um aumento significativo nos tempos operacionais.

Early mobilization after total hip or knee arthroplasty: a substudy of the POWER. 2 study

Abstract Background Early mobilization after surgery is a cornerstone of the Enhanced Recovery After Surgery (ERAS) programs in total hip arthroplasty (THA) or total knee arthroplasty (TKA). Our goal was to determine the time to mobilization after this surgery and the factors associated with early mobilization. Methods This was a predefined substudy of the POWER.2 study, a prospective cohort study conducted in patients undergoing THA and TKA at 131 Spanish hospitals. The primary outcome was the time until mobilization after surgery as well as determining those perioperative factors associated with early mobilization after surgery. Results A total of 6093 patients were included. The median time to achieve mobilization after the end of the surgery was 24 hours [16-30]. 4,222 (69.3%) patients moved in ≤ 24 hours after surgery. Local anesthesia [OR = 0.80 (95% confidence interval [CI]: 0.72-0.90); p= 0.001], surgery performed in a self-declared ERAS center [OR = 0.57 (95% CI: 0.55-0.60); p< 0.001], mean adherence to ERAS items [OR = 0.93 (95% CI: 0.92-0.93); p< 0.001], and preoperative hemoglobin [OR = 0.97 (95% CI: 0.96-0.98); p< 0.001] were associated with shorter time to mobilization. Conclusions Most THA and TKA patients mobilize in the first postoperative day, early time to mobilization was associated with the compliance with ERAS protocols, preoperative hemoglobin, and local anesthesia, and with the absence of a urinary catheter, surgical drains, epidural analgesia, and postoperative complications. The perioperative elements that are associated with early mobilization are mostly modifiable, so there is room for improvement.

Primary repair for concurrent bilateral intertrochanteric fracture and femoral head necrosis with prolonged shank biologic total hip replacement: A case report and surgical techniques / 中华创伤杂志(英文版)

For the treatment of an intertrochanteric fracture combined with femoral head necrosis in middle-age patients, it has been controversial whether to perform fracture reduction and fixation first then total hip replacement, or direct total hip replacement. We present a rare case of 53-year-old male patient suffered from bilateral intertrochanteric fracture caused by a road traffic injury. The patient had a history of femoral head necrosis for eight years, and the Harris score was 30. We performed total hip replacement with prolonged biologic shank prostheses for primary repair. One year after the surgery, nearly full range of motion was achieved without instability (active flexion angle of 110°, extension angle of 20°, adduction angle of 40°, abduction angle of 40°, internal rotation angle of 25°, and external rotation angle of 40°). The Harris score was 85. For the middle-aged patient with unstable intertrochanteric fractures and osteonecrosis of the femoral head, we can choose primary repair for concurrent bilateral intertrochanteric fracture and femoral head necrosis with prolonged shank biologic total hip replacement.

A medium term analysis on of therapeutic effects of bio-lengthend stem hemiarthroplasty in the treatment of unstable osteoporotic intertrochanteric fractures in elderly patients / 中国骨伤

OBJECTIVE@#To retrospectively study medium term follow up outcomes effects of effect of bio-lengthend stem hemiarthroplasty in the treatment of unstable osteoporotic intertrochanteric fractures in elderly patients.@*METHODS@#Total of 32 elderly patients with the osteoporotic intertrochanteric fractures were treated with bio-lengthend stem hemiarthroplasty from Jan. 2016 to Jan. 2019 including 14 males and 22 females, aged from 85 to 95 years old with an average of (89.5±4.5) years old. According to classification of Evans, there were 12 cases with type Ⅲ, 11 with type Ⅳ and 9 with type Ⅳ. The time from injury to operation ranged from 0.5 to 9 days with an average of (4.5±3.9) days. The operation time, blood loss and postoperative complications were analyzed. Functional outcome was assessed by Parker Palmer mobility score(PPMS) and Harris hip score.@*RESULTS@#Four patients died within one year after operation, and the mortality was 12.5%. The follow up time for the rest 28 patients ranged from 24 to 60 months with an average of (28.5±4.5) months. The mean operative time was (54.2±22.5) min;the mean blood loss (hidden blood loss+obvious blood loss) was (450±140) ml;the first weight bearing was (3.35±1.35) days. No perioperative death occurred. PPMS were(6.63±1.25), (6.94±1.18), (7.11±0.83), (7.32±1.11) and Harris scores were(67.85±6.19), (71.42±5.57), (73.41±5.62), (77.32±5.24) respectively at 1, 3, 6 months and the final follow-up after operation. There were no significant difference in PPMS and Harris score at 1, 3, 6 months after operation and the final follow-up(P>0.05). There were no complications such as joint dislocation and prosthesis loosening occure at the final follow-up.@*CONCLUSION@#On the premise of strictly mastering the case selection criteria, the bio-lengthend stem hemiarthroplasty in the treatment of unstable osteoporotic intertrochanteric fractures in elderly patients has a satisfied medium term follow-up outcomes. It can restore hip function in the early stage and improve the quality of life of patients.

Effect of posture on total hip arthroplasty through direct anterior approach / 中国骨伤

OBJECTIVE@#To investigate the effect of different postures on direct anterior approach(DAA) total hip arthroplasty.@*METHODS@#Total of 94 patients who underwent DAA total hip arthroplasty from July 2016 to June 2020 were retrospectively analyzed. They were divided into two groups according to different positions during the operation, including 45 cases in lateral position and 49 cases in supine position (with the aid of stent). The general data such as gender, affected limb, body mass index(BMI), incision length, operation time, intraoperative bleeding volume, drainage volume 24 hours after operation, hemoglobin difference before and after operation, first landing time after operation, postoperative hospitalization time, postoperative complications, visual analogue scale(VAS) at 1 day, 1, 2 weeks, 1, 3 and 6 months after operation, Harris score at 1, 2 weeks, 1, 3 and 6 months after operation were observed and compared between the two groups.@*RESULTS@#Patients in both groups were followed up for 6 to 12 months with an average of (8.31±2.22) months. There was no significant difference between two groups in gender, affected limb, age, height, weight, body mass index(BMI), preoperative VAS score and preoperative Harris score(P>0.05). The incision length, operation time, intraoperative bleeding volume, 24-hour drainage volume, hemoglobin difference before and after operation, first time to the ground and postoperative hospitalization time of patients in supine position (assisted by stent) group were all better than those in lateral position group(P<0.05);There was no significant difference in the number of blood transfusions during and after operation(P=0.550). There was no significant difference in anteversion angle and abduction angle in the supine position(with the aid of stent) group during and after operation (P=0.825, P=0.066);There was significant difference in anteversion angle and abduction angle in the lateral position group during and after operation(P<0.05). VAS of patients in supine position (assisted by stent) group were lower than those in lateral position group at 1 day, 1, 2 weeks and 1 month after operation(P<0.05), and there was no statistical difference between two groups at 3 and 6 months after operation(P>0.05). Harris scores of patients in supine position(assisted by stent) group were higher than those in lateral position group at 1 week, 1 month and 3 months after operation(P<0.05), and there was no significant difference between two groups at 6 months after operation(P>0.05).@*CONCLUSION@#Compared with the lateral position, the supine position DAA total hip arthroplasty has the advantages of small incision, short operation time, less bleeding, early landing time, short hospitalization time, and small intraoperative acetabular cup position judgment error. It has the advantage of fast postoperative recovery, but the recovery of hip joint function is the same after 6 months.

Comparison of filling ratio, alignment, and stability between ABG Ⅱ short-stem and Corail long-stem in total hip arthroplasty for Dorr type C femur / 中国修复重建外科杂志

OBJECTIVE@#Using the mono-energy reconstruction images and X-ray films to investigate whether the ABG Ⅱ short-stem could improve the filling ratio, stability, and alignment in the Dorr type C femur, compared with the Corail long-stem.@*METHODS@#Among patients who were with Dorr type C femurs and treated with total hip arthroplasty between January 2006 and March 2012, 20 patients with a Corail long-stem (Corail group) and 20 patients with an ABG Ⅱ short-stem (ABG Ⅱ group) were randomly selected. The differences in gender, age, body mass index, and preoperative diagnoses between the two groups were not significant ( P>0.05). The ABG Ⅱ group was with a mean follow-up of 142 months (range, 102-156 months), and the Corail group was with a mean follow-up of 107 months (range, 91-127 months). There was no significant difference in the Harris score and subjective satisfaction score between the two groups at last follow-up ( P>0.05). At last follow-up, dual-energy CT scans with mono-energy image reconstruction were used to calculate the prosthetic filling ratio and to measure the alignment of the prosthesis in the coronal and sagittal positions. Stability assessment was performed based on X-ray films, and the subsidence distance was measured using EBRA-FCA software.@*RESULTS@#X-ray film observation showed that the prostheses in the two groups were stable and no signs of loosening was found. The incidence of pedestal sign was significantly lower in the ABGⅡ group than in the Corail group ( P<0.05), and the incidence of heterotopic ossification was significantly higher in the ABGⅡ group than in the Corail group ( P<0.05). The subsidence distance of femoral stem in ABG Ⅱ group was significantly greater than that in Corail group ( P<0.05), and the subsidence speed of femoral stem in ABG Ⅱ group was also greater than that in Corail group, but the difference was not significant ( P>0.05). The overall prosthesis filling ratio was significantly higher in the ABG Ⅱ group than in the Corail group ( P<0.05), while the coronal filling ratio at the lesser trochanter, 2 cm below the lesser trochanter, and 7 cm below the lesser trochanter were not significant ( P>0.05). The results of prosthesis alignment showed that there was no significant difference in the sagittal alignment error value and the incidence of coronal and sagittal alignment error >3° between the two groups ( P>0.05), while the coronal alignment error value in the ABG Ⅱ group was significantly greater than that in the Corail group ( P<0.05).@*CONCLUSION@#Although the ABG Ⅱ short-stem avoids the distal-proximal mismatch of the Corail long-stem in the Dorr type C femur and thus achieves a higher filling ratio, it does not appear to achieve better alignment or stability.

Imaging measurement and analysis of related indexes of variation of femoral head rotation center / 中国骨伤

OBJECTIVE@#To provide guidance for hip replacement by analyzing the variation of femoral head rotation center in different hip diseases.@*METHODS@#A total of 5 459 patients were collected from March 2016 to June 2021, who took positive and proportional plain films of both hips for various reasons. The relative position between the rotation center of the femoral head and the apex of the greater trochanter was measured. The positive variation is more than 2 mm above the top of the great trochanter, and the negative variation is more than 2 mm below the top of the great trochanter. A total of 831 patients with variation of femoral head rotation center were collected and were divided into 4 groups according to different diseases, and the variation was counted respectively. There were 15 cases in the normal group involving 10 cases of positive variation and 5 cases of negative variation. There were 145 cases of avascular necrosis of femoral head involving 25 cases of positive variation and 120 cases of negative variation. There were 346 cases of congenital hip dysplasia involving 225 cases of positive variation(including 25 cases of typeⅠ, 70 cases of type Ⅱ, 115 cases of type Ⅲ and 15 cases of type Ⅳ), and 121 cases of negative variation(including 50 cases of crowe typeⅠ, 60 cases of typeⅡ, 10 cases of type Ⅲ and 1 case of type Ⅳ). There were 325 cases of hip osteoarthritis group involving 45 cases of positive variation and 280 cases of negative variation.@*RESULTS@#There was significant difference in variation of femoral head rotation center among the four groups(P<0.05). There was significant difference in variation of femoral head rotation center among different types of congenital hip dysplasia(P<0.05). There were significant differences in cervical trunk angle and eccentricity among different variations of femoral head rotation center(P<0.05).@*CONCLUSION@#The variation of femoral head rotation center is related to cervical trunk angle and eccentricity. The variation of femoral head rotation center is an important factor in hip diseases. The variation of femoral head rotation center is different in different hip diseases. Avascular necrosis of the femoral head and osteoarthritis of the hip were mostly negative variations. With the aggravation of congenital hip dysplasia, the variation of femoral head rotation center gradually changed from negative variation to positive variation.The variation of femoral head rotation center should be paid attention to in the preoperative planning of hip arthroplasty. It is of great significance to select the appropriate prosthesis and place the prosthesis accurately.