Design and clinical application of the distal femur spherical motion axis hinge knee prosthesis / 中华骨科杂志

Objective:To investigate the feasibility and early clinical efficacy of spherical motion axis hinge knee prosthesis to reconstruct distal femoral bone defects.Methods:A retrospective analysis was performed on 16 patients admitted to PLA 960th Hospital and Tianjin Hospital from October 2019 to November 2021, including 8 males and 8 females, with an average age of 43.3±17.8 years (range, 15-71 years). There were 13 patients of primary tumors of the distal femur and 3 patients of postoperative revision of knee joint prostheses. Among the 13 patients with distal femur tumors, there were 6 cases of osteosarcoma, 5 cases of giant cell tumor of bone, 1 case of leiomyosarcoma and 1 case of chondrosarcoma. The reasons for revision after prosthesis replacement in 3 cases were: 2 cases of aseptic loosening after tumor-type prosthesis and 1 case of periphery fracture of surface artificial knee prosthesis. A spherical shaft rotary hinged knee prosthesis was designed and fabricated to reconstruct postoperative femoral defects in 16 patients. Follow up regularly after the operation, recheck the X-ray film to evaluate the lower limb force line, evaluate the quality of life after the operation with the Chinese version of 36-item short-form (SF-36), and evaluate the postoperative limb function with the Musculoskeletal Tumor Society (MSTS) 93 evaluation system.Results:All 16 patients were successfully placed with prostheses, and except for 2 patients undergoing total femoral replacement, the length of bone defects was 18.2±11.7 cm (range, 8.6-47.1 cm) in other 14 patients, and the operation time was 138±19 min (range, 110-170 min), the intraoperative blood loss was 211±118 ml (range, 100-500 ml). The postoperative full length orthostatic X-ray film of the lower limbs showed that the distance between the mechanical axis of the lower limb and the center of the knee joint was 0.1 (0, 0.7) cm in 16 patients, and the hip-knee ankle angle was 179.0°±2.3°(range, 173.3°-182.2°). The patients were followed up for 12-36 months. No prosthesis complications were found in 16 patients. The SF-36 score was 56.7±7.0 (range, 42.7-67.4) for physiological function and 54.1±7.6 (range, 40.5-66.3) for psychological function. The maximum knee flexion angle was 120.0°±15.6° (range, 95°-130°). The MSTS 93 score of 15 patients with tumor was 25.0±1.7 (range, 22-28), including 7 excellent and 8 good. One patient developed liver and lung metastases 10 months after surgery and died 18 months after surgery. The remaining patients, as of the last follow-up, were alive and had no local recurrence or distant metastases. Tumor-free survival time was 25.8±8.4 months (range, 12-36 months).Conclusion:The spherical motion axis hinge knee prosthesis reconstruction for distal femoral bone defects is simple and fast in intraoperative prosthesis installation, and there are no prosthetic related complications during short-term follow-up. The clinical efficacy is satisfactory.

Management of periprosthetic femur fracture after total knee arthroplasty / 中华骨科杂志

Periprosthetic fracture of femur is the most common postoperative complication after total knee arthroplasty (TKA). Risk factors for periprosthetic fractures include female sex, osteoporosis/osteopenia, rheumatoid arthritis, osteoarthritis, neuromuscular disease, cognitive disorder, chronic use of corticosteroids, obesity, advanced age, infection, osteolysis around the prosthesis, knee joint ankyloses, notching of the anterior femoral cortex, etc. According to epidemiological research, the incidence of femoral periprosthetic fractures following TKA ranges from 0.3% to 2.5%. Lewis and Rorabeck classifications, the most commonly used classification of periprosthetic fractures of the femur, introduce the concept of prosthesis loosening and emphasize the ecessity of revision surgery. Other classifications include Su typing, Universal Typing System, and Rhee typing, the latest of which is the Kim typing proposed in 2022. Treatment strategies for periprosthetic femoral fractures after TKA include nonsurgical treatment, external fixation techniques, single-plate fixation, double-plate fixation, intramedullary nail fixation, and revision TKA and distal femur replacement. The purpose of this paper is to better guide the prevention and treatment of periprosthetic fractures after TKA by searching and analyzing relevant literature on periprosthetic fractures after TKA.

Combination pattern of internal fixation for periprosthesis fractures of the proximal femur after hip replacement / 中华骨科杂志

Objective:To investigate the combination of internal fixation for periprosthetic fractures of the proximal femur (PFFF) after hip arthroplasty.Methods:The data of 58 patients with periprosthetic fractures after hip arthroplasty from May 2008 to March 2022 were retrospectively analyzed, including 31 males and 27 females. The average age was 75.5±18.2 years (range, 35-95 years). There were 39 total hip arthroplasty and 19 hemiarthroplasty; 37 biological prosthesis and 21 cemented prosthesis. Intraoperative periprosthetic fractures occurred in 6 cases and 52 cases postoperatively. Unified classification system (UCS): UCS IV.3A1 type 2 cases, 3A2 type 1 case, 3B1.1 type 19 cases, 3B2.1 type 25 cases, 3B3 type 2 cases, 3C type 9 cases. Fracture site: 3 cases in zone A (greater trochanter), 46 cases in zone B (around the femoral stem), and 9 cases in zone C (distal to the tip of the femoral stem. Internal fixation is composed of primary and secondary fixation, the main fixation method was the cerclage of steel wire or titanium cable, locking compression plate, and locking attachment plate fixation. The secondary fixation method was the cerclage of titanium cable, which was required to cover three zones A, B and C to form an overall balanced fixation. The modified Harris hip scores (mHHS), plate length, working length and screw number of different internal fixation combinations were compared.Results:The follow-up time was 54.2±21.6 months (range, 11-86 months). All patients showed signs of fracture healing at 10.2±1.5 weeks (range, 7-13 weeks) after operation, and bony union was observed at 19.6±1.3 weeks (range, 17-22 weeks) after operation. No delayed union or nonunion was observed. After operation, one case had a stress fracture and was revised with double-plate internal fixation; one case had a failed internal fixation and was revised with double-plate internal fixation and a large allograft bone graft. The mHHS score of UCSIV.3B2.1 group (80.3±4.6) was the lowest at 6 months after operation, and the difference between the groups of different types was statistically significant ( F=256.72, P<0.001). The score of simple internal fixation group (91.6±4.2) was higher than that of revision combined with internal fixation group (81.9±4.1), and the difference was statistically significant ( t=8.32, P<0.001). The plate length and working length were 24.9±2.5 cm and 12.6±1.7 cm for UCS IV.3B1.1, 25.4±2.6 cm and 13.6±1.8 cm for 3B2.1 and 28.1±2.5 cm and 4.9±1.9 cm for 3C, respectively ( F=5.33, P=0.005; F=6.78, P<0.001). The number of screws in zone A was significant difference among different UCS types ( F=52.67, P<0.001); UCS IV.3B1.1 (6.5±2.3) and 3B2.1 (6.7±2.2) were more than 3B3 (3.5±1.5) and 3C (3.7±1.6). The number of screws in zone B was significant difference among different UCS types ( F=42.15, P<0.001); The number of UCS IV.3B1.1 (2.3±1.6) and 3B2.1 (2.8±1.9) were significantly more than that of 3B3 (1.0±0.5) and 3C (1.2±0.6). The number of screws in zone C was significant differences among different UCS types ( F=39.62, P<0.001); The number of UCS IV.3B1.1 (3.8±1.9) and 3B2.1 (3.9±1.7) were more than that of 3B3 (2.0±0.5), the difference was statistically significant ( P<0.05). Conclusion:The function of hip after simple internal fixation of proximal femoral periprosthetic fractures was better than that of those who underwent revision at the same time; the number of screws of UCSIV.B1 and B2 is more than that of B3.

Periprosthetic fractures: the increasing challenges / 中华创伤骨科杂志

Surgery for periprosthetic fractures (PPF) is one of the most complex procedures in orthopedics. It is difficult, highly risky and extremely challenging, because the patients are usually advanced in age and suffering from essential organ dysfunction, numerous comorbidities, poor overall body condition, poor bone quality combined with osteolysis and even bone loss, and because the surgeons have to apply the concepts and techniques of Modern Orthopedic Trauma and artificial joint revision techniques in fracture fixation and prosthesis revision. This paper expounds on the clinical challenges due to the characteristics of PPF in order to call on clinical surgeons to update their concepts, deal with seriously and standardize their PPF treatment, and effectively improve their efficacy.

Fixation with a 3D printed individualized custom-made plate for elderly patients with periprosthetic femoral fracture: an analysis of short-term efficacy / 中华创伤骨科杂志

Objective:To explore the short-term efficacy of fixation with a 3D printed individualized custom-made plate in the treatment of elderly patients with periprosthetic femoral fracture.Methods:Retrospectively analyzed were the 5 elderly patients with periprosthetic femoral fracture who had been treated by fixation with a 3D printed individualized custom-made plate from January 2022 to July 2022 at Department of Orthopaedics and Traumatology, Beijing Jishuitan Hospital. There were 3 males and 2 females, aged 81, 86, 77, 91 and 87 years, respectively. One left and 4 right limbs were affected. Vancouver classification: type B1 ( n=3), type B2 ( n=1), and type C ( n=1). The time from operation to injury was 5, 6, 10, 5 and 7 days, respectively. Preoperatively, the femur affected, prosthesis and individualized plate with a greater trochanteric hook, loop cable channel and bone-like trabecular microporous structure were custom-made by 3D printing according to 1:1 models. Virtual operations were simulated to formulate surgical protocols. The operation time, length of surgical incision, intraoperative blood loss and transfusion, hospital stay, hip function and complications at the last follow-up were recorded. Results:The 5 patients were followed up for 12, 7, 10, 3 and 6 months, respectively. There were no events of superficial incision or deep prosthesis infection. Respectively, the operation time was 1.8, 1.7, 2.3, 2.0 and 3.3 h; the length of surgical incision 31, 30, 38, 27 and 30 cm; the intraoperative bleeding volume 400, 300, 300, 500 and 600 mL; the length of hospital stay 8, 9, 15, 14 and 11 d. Four patients received intraoperative blood transfusion of 300, 900, 150 and 1, 050 mL, respectively. One patient died of a heart attack 3 months after discharge; another patient developed dyskinesia at the contralateral limb 3 months after discharge due to cerebral infarction and died of recurrent cerebral infarction 7 months after discharge. At the last follow-up, the Harris hip scores of 3 patients were 86, 77 and 69 points, respectively. None of the patients had complications like breakage or loosening of implants.Conclusion:In the treatment of elderly patients with periprosthetic femoral fracture, fixation with a 3D printed individualized custom-made plate may lead to fine limb function and good short-term curative efficacy.

Radiographic Characteristics of the Femoral Nutrient Artery Canals in Total Hip Arthroplasty using Cementless Femoral Stem

@#Introduction: Accurate diagnosis of undisplaced periprosthetic femoral fracture (PFF) after hip arthroplasty is crucial, as overlooked PFF may affect its treatment and prognosis. The undisplaced PFF is often difficult to distinguish from radiolucent lines of nutrient artery canal (NAC) of the femur present on post-operative radiographs. We aimed to identify the radiographic features of NAC to distinguish them from PFFs. Materials and methods: In this retrospective radiological study, a total of 242 cases in 215 patients with hip arthroplasty were analysed using pre-operative and postoperative anteroposterior (AP) and translateral (TL) radiographs. Interobserver agreement of the measurements was assessed by two independent experienced orthopaedic surgeons. The kappa value ranged from 0.83 to 0.87, indicating strong agreement according to the Landis and Koch criteria. Results: The NACs were found pre-operatively in 94 (39.8%) cases on AP views and in 122 cases (50.4%) on TL views. The radiolucent lines were observed post-operatively in 42 (17.4%) on AP views and 122 (50.4%) on the TL views. three cases (1.2%) had a fracture around the stem that were detected on radiographs. One case with PFF presented simultaneously with NAC on the immediate post-operative radiographs. All patients were treated by conservative measures, and the radiolucent lines did not appear on followup radiographs. Conclusion: It is not easy to differentiate undisplaced PFFs that can occur after hip arthroplasty operation from NACs. However, accurate diagnosis is possible through careful observation and comparison of pre-operative and postoperative radiologic images

Coagulation Factors for Diagnosis of Periprosthetic Joint Infection / 中山大学学报(医学科学版)

ObjectivePeriprosthetic joint infections （PJI） are currently the most calamitous complication after arthroplasty. Although achievements have been made in many markers for the diagnosis of PJI， the lack of a gold standard remains a great obstacle for early diagnosis. This study aimed to investigate the association between coagulation markers and the development of PJI in patients undergoing revision total joint arthroplasty （TJA）. MethodsWe conducted a retrospective cohort study with a total of 2 517 patients who underwent hip or knee arthroplasties from January 2011 to January 2022 （2 394 with primary TJA， 87 with aseptic revision and 36 with PJI）. We applied univariate analysis and multivariate logistic regression to analyze differences of coagulation factors between primary TJA and aseptic revision or PJI group. Receiver operating characteristic （ROC） curve and area under the curve （AUC） were used to measure the diagnostic value of coagulation factors in predicting PJI. ResultsCoagulation factors and their ratios including plasma fibrinogen （FBG）， prothrombin time （PT）， thrombin time （TT）， activated partial thromboplastin time （APTT）， platelet （PLT）， mean platelet volume （MPV）， platelet distribution width （PDW）， plateletcrit （PCT）， PLT / MPV， PLT / PDW and PLT / PCT were included in this study. High FGB level was strongly correlated with the risk of PJI compared to other coagulation factors. The optimal threshold value of FBG was 4.53 g/L with a sensitivity of 47.22%， a specificity of 93.07% （Primary TJA group vs. PJI group）. Similarly， the optimal threshold value of FBG was 4.44 g/L with a sensitivity of 47.22%， a specificity of 95.40% between the other two groups （Aseptic revision group vs. PJI group）. ROC curve analysis demonstrated moderate diagnostic performance of FBG （AUC value）， indicating a potential to be a diagnostic marker for PJI. ConclusionsFBG is significantly correlated with PJI and it can be used as a potential non-invasive marker for early detection. It may serve as a safe and cost-effective tool for assessing PJI in clinical work.

Debridement， Antibiotics and Implant Retention for the Treatment of Periprosthetic Joint Infection After Arthroplasty： A Narrative Review / 中山大学学报(医学科学版)

Periprosthetic joint infection （PJI） following joint arthroplasty is devastating and technique-demanding. At present， the surgical treatment for PJI includes debridement， antibiotics， and implant retention （DAIR）， single- or two-stage revision， arthrodesis， and amputation. DAIR is appealing to both surgeons and patients as it can avoid unnecessary implants removal， making it less time-consuming and less invasive. In this article， we review the current knowledge in surgical timing， intraoperative details and antibiotics strategy of DAIR.

Periprosthetic gout flare after total knee arthroplasty: A misdiagnostic case report / 北京大学学报(医学版)

Periprosthetic gout flare is a rare arthritic condition after total knee arthroplasty, but the symptoms of gout may have often been mistaken as acute periprosthetic infection given their similarity. Misdiagnosis as periprosthetic infection can lead to unnecessary surgery, long-term dependence on anti-biotics, and even malfunction of the involved knee joint. Here, we report a case study of a patient with immunodeficiency condition of long-term oral glucocorticoid and diabetes mellitus, who had undergone a knee replacement 8 weeks before. The initial symptoms of fever and joint pain together with the dysfunction of her right knee with elevated inflammatory markers, such as increased serum leukocytes, erythrocyte sedimentation rate, C-reactive protein, and synovial cell counts led to a diagnosis of acute periprosthetic infection. Arthrocentesis and bacterial culture were performed preoperatively. According to the current Musculoskeletal Infection Society (MSIS) criteria for diagnosis of periprosthetic infection, the case was classified as periprosthetic infection and a prosthesis retained debridement surgery was performed. However we got negative culture results in all the pre-operative and intro-operative samples. The symptoms as well as the laboratory inflammatory markers improved shortly after the debridement surgery until the 11th day when all the similar systemic and local symptoms recurred. With a remedial crystal analysis of synovial fluid from the patient, gouty flare was found to be the cause of acute arthritis finally. Accor-dingly, after anti-gout medications were administrated, the symptoms associated with acute arthritis gra- dually subsided, and there was no recurrence during a 24-month follow-up. This article described the cli-nical manifestation, diagnosis and differential diagnosis, treatment of a case of periprosthetic gout. Although relatively rare, gout should be considered as a differential diagnosis in suspected periprosthetic infection. Current criteria for periprosthetic infection can not exclude the diagnosis of periprosthetic gout flare, it is therefore imperative that the analysis of joint aspirate for crystals be conducted to determine the correct course of treatment, or unnecessary surgical procedure may be performed in periprosthetic gout case.

Construction and evaluation of a nomogram prediction model for periprosthetic fractures after total hip arthroplasty / 中国骨伤

OBJECTIVE@#To construct and evaluate nomogram prediction model for periprosthetic fractures in patients undergoing total hip arthroplasty (THA).@*METHODS@#A total of 538 patients who underwent THA from April 2013 to February 2019 were selected as the research subjects, including 318 males and 220 females, aged 40 to 60 years old with an average age of (50.79±6.37) years old. All patients with THA were divided into non-fracture group (506 patients) and fracture group (32 pathents) according to the 3-year follow-up results. Univariate and multivariate Logistic regression analyses were performed to analyze the influencing factors of postoperative periprosthetic fractures in patients with THA. A nomogram prediction model for periprosthetic fractures in patients undergoing THA was constructed, and the validity and discrimination of the prediction model were evaluated.@*RESULTS@#The proportion of patients with osteoporosis, trauma history, and hip revision in the fracture group were higher than those in the non-fracture group(P<0.05), and the proportion of bone cement prosthesis was lower than that in the non-fracture group(P<0.05). The osteoporosis status[OR=4.177, 95%CI(1.815, 9.617), P<0.05], trauma history[OR=7.481, 95%CI(3.104, 18.031), P<0.05], and hip revision[OR=11.371, 95%CI(3.220, 40.153, P<0.05] were independent risk factors for postoperative periprosthetic fractures in patients undergoing THA, cemented prosthesis [OR=0.067, 95%CI(0.019, 0.236), P<0.05] was an independent protective factor for postoperative periprosthetic fractures in patients undergoing THA(P<0.05). Hosmer-Lemeshow goodness of fit test showed that χ2=7.864, P=0.325;the area under the curve (AUC) for periprosthetic fractures in patients undergoing THA was 0.892 with a sensitivity of 87.5% and a specificity of 77.7% by receiver operating characteristic(ROC) curve.@*CONCLUSION@#The nomogram prediction model for periprosthetic fractures after THA constructed in this study has good discrimination, which is beneficial to clinical prediction of periprosthetic fractures in patients undergoing THA, and facilitates individualized fracture prevention.

Accuracy of Serological Markers, Synovial Fluid, Microbiological Culture, and Histopathological Examination for Diagnosing Periprosthetic Knee Infection / Acurácia dosmarcadores sorológicos, do líquido sinovial, cultura microbiológica e exame histopatológico para o diagnóstico de infecção periprotética do joelho

Abstract Objective This study assessed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of serological tests, synovial fluid markers, microbiological tissue culture, and histopathological examination of the periprosthetic membrane in diagnosing periprosthetic knee infection. Methods This study is prospective, and it includes patients undergoing total knee arthroplasty revision surgery from November 2019 to December 2021. The analysis consisted of serological tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and D-dimer), synovial fluid markers (leukocyte and polymorphonuclear cell counts), periprosthetic tissue culture, and histopathological examination of the periprosthetic membrane of all patients. Results Sixty-two patients had periprosthetic joint infection (PJI) according to the 2018 International Consensus Meeting criteria (infection group), while 22 subjects had no infection. ESR sensitivity and specificity were 83.6% and 45.4%, respectively. CRP sensitivity and specificity were 64.5% and 100%, whereas D-dimer sensitivity and specificity were 78.9% and 25%, respectively. Leukocyte count sensitivity and specificity were 75.6% and 100%, polymorphonuclear cell count sensitivity and specificity were 33% and 100%, respectively. Periprosthetic tissue culture sensitivity and specificity culture were, respectively, 77.4% and 100%. Histopathological examination sensitivity and specificity were 43.7% and 100%, respectively. Conclusions In our study, the total blood cell count in synovial fluid and microbiological cultures of periprosthetic tissues were the most accurate tests for PJI diagnosis. In contrast, polymorphonuclear cell percentage was the least accurate test for PJI diagnosis.

Resumo Objetivo avaliar a sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia dos testes sorológicos, dos marcadores do líquido sinovial, da cultura microbiológica de tecidos e do exame histopatológico da membrana periprotética para o diagnóstico de infecção periprotética do joelho. Métodos estudo prospectivo, com pacientes submetidos à cirurgia de revisão de artroplastia total do joelho no período entre novembro de 2019 e dezembro de 2021. Foi realizado análise do marcadores sorológicos (VHS,PCR e D-dímero), do líquido sinovial (contagem de leucócitos e percentual de polimorfonucleares), cultura de tecidos periprotéticos e exame histopatológico da membrana periprotética de todos os pacientes. Resultados 62 pacientes foram diagnosticados com infecção periprotética do joelho, pelos critérios do International Consensus Meeting 2018 (grupo infecção) e 22 pacientes integraram o grupo não infecção. A sensibilidade e especificidade da VHS foram de 83,6% e 45,4%, respectivamente. Os valores de sensibilidade e especificidade da PCR foram de 64,5% e 100% e as do D-dímero foram de 78,9%% e 25%, respectivamente. A sensibilidade e especificidade da contagem de leucócitos foi de 75,6% e 100%, e a do percentual de polimorfonucleares foi de 33% e 100%, respectivamente. A sensibilidade e especificidade das culturas de tecidos periprotéticos foi de, respectivamente, 77,4% e 100% A sensibilidade do exame histopatológico foi de 43,7% e a especificidade de 100%. Conclusões A contagem total de leucócitos no líquido sinovial e as culturas microbiológicas dos tecidos periprotéticos foram os testes de maior acurácia para o diagnóstico de infecção periprotética em nossa série. O percentual de polimorfonucleares foi o teste de menor acurácia, em nosso estudo, para o diagnóstico de infecção periprotética.

Microbiología de las infecciones periprotésicas de rodilla en Hospital Regional de Talca / Microbiology of periprosthetic knee infections in Regional Hospital

Introduction: Periprosthetic infection (PPI) is one of the most devastating complications of total knee arthroplasty (TKA). The incidence described in the literature is 2.4% and the most frequently isolated bacteria are Staphylococcus Aureus and Staphylococcus Coagulase-Negative (Gram positive). Polymicrobial infections represent between 10 to 37% and negative cultures between 7 to 15%. Methodology: Descriptive and retrospective study that consisted of reviewing the TKA database of the Regional Hospital of Talca during the 2018-2020 period, where knee PPIs were identified according to the diagnostic criteria validated in 2018. The cultures of patients diagnosed with PPI were reviewed, analyzing the antibiogram and resistance profile. Results: During 2018-2020, 459 TKAs were performed in our center, diagnosing 30 PPIs of the knee. 47% of PPIs were acute and 53% chronic. The results of the cultures were negative in 26.6%, 23.3% Methicillin Sensitive Staphylococcus Aureus; 13.3% Methicillin Resistant Staphylococcus Epidermidis and 13.3% of the cultures were polymicrobial. Discussion: Highlights the high resistance to methicillin, especially of Staphylococcus Epidermidis. This opportunistic pathogen has the ability to form a biofilm and, thanks to its genomic flexibility, rapidly acquires resistance to antibiotics. Polymicrobial infections have a synergistic effect that favors the persistence of the infection, which is why they will require a greater number of surgeries and prolonged antibiotic therapy. Pruebas especiales como la sonicación podrían aumentar las posibilidad de identificar al microorganismo. Conclusion: In these three years of follow-up, the PPI rate has been higher than reported annually in the literature. Gram-positive microorganisms continue to predominate, but with an increase in the rate of resistant to methicillin. Also, highlight the number of negative cultures. There would be a possible benefit theoretical in optimizing antibiotic prophylaxis in view of the large percentage of methicillin resistance and in seeking new ways to reduce negative cultures.

Infecciones periprotésicas en artroplastia total de rodilla: ¿cuál es nuestra realidad? / Periprosthetic infections in total knee arthroplasty: what is our reality?

INTRODUCCIÓN La infección periprotésica (IPP) es una de las complicaciones más serias en una artroplastia total de rodilla (ATR). Pese a esto, existe poca literatura chilena respecto de esta patología. OBJETIVOS Determinar la incidencia, las comorbilidades, los microorganismos aislados y su susceptibilidad antibiótica, y la morbimortalidad en pacientes con IPP. MATERIALES Y MÉTODOS Estudio descriptivo y retrospectivo en pacientes operados entre 2001 y 2020 por gonartrosis, con una ATR primaria, en un mismo centro de salud, con al menos 1 año de seguimiento. Se excluyeron pacientes operados en otros centros o con registros clínicos incompletos. Se registraron las comorbilidades, los microorganismos aislados, la susceptibilidad antibiótica, y la sobrevida por medio de una búsqueda sistemática de las fichas clínicas de los pacientes con IPP. Se utilizó estadística descriptiva para presentar los datos. RESULTADOS Se incluyeron 544 ATRs, de las cuales 8 (1,47%) presentaron IPP, y los pacientes tenían una edad promedio de presentación de 66 (±5,7) años, e índice de masa corporal (IMC) promedio de 30,3 (±4,5) kg/m2. La mediana de tiempo de presentación de la IPP fue de 411 (±1.034) días. Las principales comorbilidades registradas fueron hipertensión arterial en 5 (62,5%), tabaquismo en 4 (50%) casos, y dislipidemia in 4 (50%) casos. En total, 5 (62,5%) pacientes presentaron etiología polimicrobiana, y en 3 (37,5%) se aisló un solo microorganismo. Los principales agentes aislados fueron Staphylococcus aureus y Staphylococcus coagulasa negativo, ambos multirresistentes, en 6 (75%) y 3 (37,5%) pacientes respectivamente. Todos los pacientes recibieron tres dosis de cefazolina como profilaxis quirúrgica. Se describe una sensibilidad del 100% frente a vancomicina y rifampicina (12/12 cultivos), y una resistencia del 83,4% al ciprofloxacino (4/9 cultivos). Un total de 2 (25%) pacientes fallecieron después de 3 años de la ATR por causas no relacionadas con la IPP. No hubo casos de recidiva infecciosa tras la revisión. CONCLUSIÓN Se encontró una incidencia de 1,47% (8 casos) de IPP. Todos los pacientes con IPP presentaron alguna comorbilidad prequirúrgica. Los principales agentes microbiológicos identificados fueron multirresistentes y susceptibles a vancomicina y rifampicina.

INTRODUCTION Periprosthetic infection (PPI) is one of the most serious complications in total knee arthroplasty (TKA). Despite this, there is little Chilean literature regarding this pathology. OBJETIVES To determine the incidence, comorbidities, isolated microorganisms and their antibiotic susceptibility, morbidity, and mortality in patients with PPI. MATERIALS AND METHODS A descriptive and retrospective study in patients operated between 2001 and 2020 for gonarthrosis, with a primary TKA, in the same health center, with at least 1 year of follow-up. Patients operated on in other centers or with incomplete clinical records were excluded. Comorbidities, isolated microorganisms, antibiotic susceptibility, and survival were recorded through a systematic search of the clinical records of patients with PPI. Descriptive statistics were used to present the data. RESULTS We included 544 TKAs, 8 (1.47%) of which presented PPI, and the patients had an average age at presentation of 66 years ( 5.7 years) and an average body mass index (BMI) of 30.3 ( 4, 5) kg/m2 . The median time of presentation of the PPI was of 411 ( 1,034) days. The main comorbidities recorded were arterial hypertension in 5 (62.5%), smoking in 4 (50%) cases, and dyslipidemia in 4 (50%) cases. In total, 5 (62.5%) patients presented polymicrobial etiology, and in 3 (37.5%), a single microorganism was isolated. The main isolated agents were Staphylococcus aureus and coagulasenegative Staphylococcus, both multidrug-resistant, in 6 (75%) and 3 (37.5%) patients respectively. All patients received three doses of cefazolin as surgical prophylaxis. A sensitivity of 100% to vancomycin and rifampicin (12/12 cultures), and a resistance of 83.4% to ciprofloxacin (4/9 cultures) were described. Overall, 2 (25%) patients died 3 years after the TKA, due to causes unrelated to PPI. There were no cases of infectious relapse after the review. CONCLUSION An incidence of 1.47% (8 cases) of PPI was found. All patients with PPI presented some presurgical comorbidity. The main microbiological agents identified were multidrug-resistant and susceptible to vancomycin and rifampicin

Single center experience of transcatheter closure of mitral and aortic Paravalvular leaks using the new rechristened rectangular Amplatzer PVL plug

Amplatzer Paravalvular leak (PVL) plug is rectangular in shape, that might suit closure of crescentic PVL. Among 79 transcatheter PVL closures from a single center, a subgroup of 16 patients who received Amplatzer PVL plugs were analyzed. All procedures were successful, as the plug auto-oriented to the leak, without mechanical leaflet interference, though needing additional 31 devices. Two patients needed an elective re-intervention. NYHA class improved from III-IV before procedure to less than II after procedure. Complications were not directly related to the Amplatzer PVL plug. The rectangular shape for crescentic leaks, auto-orientation and non-interference with mechanical leaflets were good attributes.

Periprosthetic Femur Fracture in a 73-Year-Old Female: A Case Report

Increasing use of joint replacement for various conditions has led to a new group of fractures- the periprosthetic fractures. Periprosthetic fractures are considered which are associated with an orthopaedic implant. Worldwide incidence of Periprosthetic fractures is increasing due to increased number of primary joint arthroplasties and other revision surgeries. Periprosthetic femoral fracture can be classified as intraoperative & post-operative. The intraoperative periprosthetic fractures usually occur during the insertion of the femoral stem, often preceded by an area of increased cortical thickness. The management of these fractures are complex and usually needs application of basic principles to fit an individual situation rather than having a fixed set of rules. Standard treatment protocol includes use of locking plate with encirclage wires. In this study, we provide a case of periprosthetic femur fracture pain. A 75-year-old woman presented to us with pain in her right hip and thigh. The patient was a homemaker who had cemented total hip replacement surgery due to a femoral neck fracture 27 days back. After the primary replacement surgery, the patient appeared to be doing well and adhering to the hip precautions. While getting out of bed, she tripped and fell carelessly in the morning & complained of severe pain in her right hip. After assessment of all her medical conditions and physical examination, she was advised for revision surgery. An open reduction and internal fixation of the fracture with revision of the femoral component was planned. Risks, benefits, and alternatives were discussed at length with her and her family. The patient and her family agreed to the operative plan.

Treatment of trochanter fractures in total hip arthroplasty with ventral compression steel wire tension band / 中华骨科杂志

Objective:To evaluate the various wire tension belt ventral compression wiring technologiesfor treating several types of femoral greater trochanter fractures in total hip replacement, according to the different types of greater trochanter of femur fractures.Methods:From March 2013 to June 2019, a total of 1 280 cases of primary total hip arthroplasty were completed in our hospital, 21 patients with greater trochanter fractures were identified in total hip replacement. There were 11 males and 10 females with an average age of 65.81±6.45 years (range 42-76 years). All of them were unilateral. There were 11 cases on the left and 10 cases on the right. There were 11 cases of osteoarthritis secondary to hip dysplasia, 4 cases of hip osteoarthritis, 4 cases of aseptic necrosis of femoral head and 2 cases of femoral neck fracture. Different wire tension belt ventral compression wiring technologies were used for each fracture type. Harris hip function score, Parker activity score, and visual analogue scale (VAS) score of hip pain were evaluated during follow-up. X-ray films were taken to evaluate the fracture healing, prosthesis position, loosening and dislocation.Results:Three new fracture types were proposed: A transverse fracture from the greater trochanter tip to the base (4 cases); B oblique fracture from the greater trochanter tip to the base (according to the fracture line direction, type B was further divided into types B1 (4 cases) and B2 (6 cases); and C fracture line from the greater trochanter to subtrochanteric plane (7 cases). Among the 21 patients, one died at an early stage, two were lost during follow-up, and 18 were followed up for an average of 30.7±7.6 months. In 18 patients, the mean operation time was 110.0±20.0 min, and the mean intraoperative blood loss was 356.9±115.7 ml. The patients' Harris score was 35.26±5.52 at the preoperative, 65.7±6.42 at the 3 months after operation, and 87.75±6.21 at the final follow-up. The difference was statistically significant ( F=377.23, P<0.001). The patients' Parker score was 2.17±0.98 at the preoperative, 5.94±1.11 at the 3 months after operation,and 8.01±0.77 at the final follow-up. The difference was statistically significant ( F=170.96, P<0.001). The patients' VAS score was 6.22±1.11 at the preoperative, 2.61±0.92 at the 3 months after operation, and 1.28±0.67 at the final follow-up. The difference was statistically significant ( F=139.71, P<0.001). Deep vein embolism, heterotopic ossification was noted in one and another patient, respectively. The patient with non-union refused reoperation and had a broken steel wire, lower-limb limp, and no notable pain at the 12-month follow-up examination. Radiographs of 17 patients showed good location of the femoral prosthesis and no chronic pain. Conclusion:Different types of greater trochanter fractures in total hip arthroplasty were proposed, using different wire tension belt ventral compression wiring technologies for the various types of femoral greater trochanter fractures during total hip replacement can improve clinical outcomes.

Effect of Notch on femoral periprosthetic fractures after primary total knee arthroplasty / 中华骨科杂志

Objective:To investigate the effect of Notch on periprosthetic fracture (PPF) of the femoral prosthesis after primary total knee arthroplasty.Methods:A total of 34 patients diagnosed with femoral PPF at Xi'an Honghui Hospital were retrospectively collected from January 2013 to December 2020. There were 4 males and 30 females with a mean age of 69.2±7.2 years (range, 55-84 years). A total of 102 patients without PPF were matched by gender and age as the control group in a ratio of 1∶3. There were 12 males and 90 females with a mean age of 69.2±7.2 years (range, 55-84 years). The main observation indexes included patients' general information and factors such as coronal alignment, prosthesis design and Notch conditions. Then, subgroup analysis was performed with the depth and Tayside classification of Notch to analyze their effects on PPF.Results:The PPF and control groups were comparable in terms of baseline information such as gender, age, body mass index (BMI), and surgical side. There was no significant difference between the two groups in coronal alignment (χ 2=1.019, P=0.601) and prosthesis design (χ 2=1.545, P=0.214). There was no statistical difference in Notch between the PPF and control groups (χ 2=3.548, P=0.060). The mean length of Notch in the PPF group was 4.5±2.7 mm, compared with 4.9±2.8 mm in the control group, with no significant difference between the two groups ( t=0.732, P=0.465). Further subgroup analysis using a Notch depth of 3 mm as a cut-off and Tayside classification revealed a statistical difference between the two groups (χ 2=11.262, P=0.004; χ 2=14.601, P=0.003). Compared with patients without Notch, the risk of PPF was higher when the depth of Notch exceeded 3 mm, with an odds ratio ( OR) of 4.88 (95% CI: 1.76, 13.51). The incidence of PPF was higher when Notch depth reached Tayside grade 3 or 4. Compared with patients without Notch, the risk of PPF would be 6.99-fold (95% CI: 1.85, 26.32) higher when Notch depth reached grade 3. In female patients, there was a significant difference in Notch status between the PPF and control groups (χ 2=3.956, P=0.047), with a higher risk of PPF in female patients with Notch, OR 2.33 (95% CI: 1.01, 5.43). In patients who underwent right-sided TKA, the risk of PPF was higher in patients with Notch compared to those without Notch (χ 2=5.502, P=0.019), with an OR of 3.58 (95% CI: 1.19, 10.75). Conclusion:The Notch has no significant effect on the femoral PPF after primary total knee arthroplasty. However, the risk of PPF will increase significantly when the Notch depth exceeds 3 mm or is above Tayside grade 3.

Biomechanical comparison of Ortho-Bridge system and plate fixation system for femoral periprosthetic type Vancouver B1 fracture / 中华骨科杂志

Objective:To compare the biomechanical parameters of Ortho-Bridge system (OBS) and locking compression plate+locking attachment plate (LCP+LAP) in the fixation of femoral periprosthetic type B1 fracture.Methods:The same periprosthetic type B1 fracture of human femur were made, including simple fracture model and comminuted fracture model, 12 in each. And the simple fracture models were randomly divided into 6 pieces of OBS system fixation group and 6 pieces of LCP+LAP system fixation group, and the complex fracture models were also randomly divided into 6 pieces of OBS system fixation group and 6 pieces of LCP + LAP system fixation group. Then the four groups of models were tested by axial compression and torsion tests, and the stiffness of the models under axial compression and torsion angle of the models under torsion test were collected. The axial compression failure test was carried out to collect the vertical load of the ultimate failure test. The axial stiffness, torsion angle and axial failure load of OBS and LCP+LAP fixed simple and comminuted fractures were statistically analyzed by t test. Results:For the test of fixed simple fracture, there was no significant difference ( t=0.535, P=0.522) in the axial stiffness between the OBS group (868.87±157.14 N) and the LCP+LAP group (904.53±44.76 N), whereas the results of torsion test showed that the LCP+LAP group had a higher torsion angle 7.17°±0.52° than the OBS group 5.45°±0.44° ( t=5.616, P<0.001); When fixing comminuted fractures, the OBS group had a higher axial stiffness (145.33±10.34 N) than the LCP+LAP group (84.15±8.94 N) ( t=10.961, P<0.001), but the LCP+LAP group had a higher torsion angle 7.75°±1.17° than the OBS group 5.23°±0.31° ( t=4.652, P=0.001). Ultimate failure test data showed that the failure pressure of OBS fixed group (4 967.49±132.88 N) was higher than LCP+LAP group (3 967.41±145.16 N) ( t=12.447, P<0.001). In the LCP+LAP group, there was destruction of the contact cortex at the fracture site, while in the OBS group, there was destruction of the contact cortex at the fracture site as well as fractures around the proximal fixation screw. Conclusion:OBS group has similar axial compression resistance to LCP+LAP group, but better torsion resistance than LCP+LAP group when it is used to fix B1 simple fracture around femoral prosthesis. When comminuted fracture is fixed, the axial compression resistance and torsion resistance of OBS group are better than LCP+LAP group. The stress is dispersed during OBS fixation, which can better avoid the failure of internal fixation during early functional exercise.

Study on the intenal fixation of distal femoral fracture with Ortho-Bridge system in elderly patients / 中华骨科杂志

Objective:To introduce the surgical method of Ortho-Bridge system (OBS) in the treatment of distal femoral fractures in elderly patients and investigate its clinical effect.Methods:From January 2018 to July 2021, 24 elderly patients who suffered distal femoral fractures were treated with bilateral OBS. There were 8 males and 16 females aging from 62 to 87 years, with an average age of 72.6 years. It included 15 cases of simple distal femoral fractures. According to AO classification, there were one case of A1, two of A2, five of A3, two of C1, three of C2 and two of C3. Nine cases of femoral periprosthetic fractures after total knee arthroplasty (TKA) were classified as type II according to rorabeck's classification. After operation, all patients were guided to perform knee joint functional exercise and to measure the range of motion of the knee joint. Then imaging examinations were used to evaluate the fracture healing and measure the femoral-tibial and femoral angles. The American Hospital for Special Surgery (HSS) knee joint scoring system was used to evaluate the knee function.Results:All 24 patients successfully completed the operation. The operation time was 84-115 min, with an average of 96.6 min; the intraoperative blood loss was 150-335 ml, with an average of 240 ml. All patients were followed up for 8-17 months, with an average of 13.6 months. Except for 1 case of nonunion due to few primary bone grafts, which required secondary bone grafting, the other 23 cases achieved bone union. The healing time was 3.5-6 months, with an average of 4.6 months. At 1, 3, and 6 months after operation and at the last follow-up, the flexion angles of knee were 92.2°±10.2°, 98.6°±13.3°, 106.4°±13.7°, 115.7°±15.3°, and the extension angles were -4.7°±4.1°, -1.2°±4.2°, 0.7°±4.5°, 1.8°±4.6°, respectively; and all differences were statistically significant ( F=17.03 and 12.68, P<0.001). The knee flexion and extension angles at the last follow-up were greater than 1, 3, and 6 months after operation, and the differences were statistically significant ( P<0.001). The femoral-tibial angle was 171.2°±2.4° and 170.7°±3.2°, and the femoral angle was 80.3°±1.7° and 79.6°±2.1°, respectively, at the immediate postoperative and last follow-up, with no significant difference. The HSS scores at 1, 3, 6 months after operation and at the last follow-up were 71.5±7.5, 74.6± 9.3, 78.9±10.4 and 84.7±9.4 respectively, with significant difference ( F=9.17, P<0.001). At the last follow-up, the HSS score was higher than that at 1, 3, and 6 months after the operation, and the differences were statistically significant ( P<0.001), and the knee function was evaluated according to the HSS scoring system: excellent in 12 cases, good in 9, fair in 3, with an excellent and good rate of 88% (21/24). There was no OBS crack or fixation failure in all patients, and no prosthetic loosening and instability occurred in patients with periprosthetic femoral fractures after TKA. Statistical analysis of the data at the last follow-up between the distal femoral fracture group and the periprosthetic femoral fracture group after TKA showed that the knee flexion function and HSS score of the periprosthetic femoral fracture group after TKA (126.8°±3.7°, 92.2±4.1) were both better than the simple distal femur fracture group (108.9°±15.7°, 80.2±8.8). The difference was statistically significant ( t=4.22, 4.52, P<0.05). One patient had incision fat liquefaction and healed after debridement; bone nonunion occurred in 1 case, which healed after iliac bone grafting. Conclusion:Double OBS has a good clinical effect in the treatment of distal femoral fractures in the elderly, especially in patients with periprosthetic femoral fractures after TKA.

Effect of single locked-plate internal fixation combined with autogenous iliac bone graft in the treatment of Rorabeck type II periprosthetic distal femoral fracture after total knee arthroplasty / 中华创伤杂志

Objective:To investigate the efficacy of single locked-plate internal fixation combined with autologous iliac bone graft in the treatment of Rorabeck type II periprosthetic distal femural fracture (PDFF) after total knee arthroplasty (TKA).Methods:A retrospective case series study was made on 13 patients suffering from Rorabeck type II PDFF after primary TKA together with severe osteoporosis (T value≤ -2.5 SD) admitted to 940th Hospital of Joint Logistics Support Force of PLA from January 2016 to December 2020, including 4 males and 9 females, aged 65-85 years [(75.2±6.5)years]. All patients were treated with single locked-plate internal fixation combined with autologous iliac bone graft. Anti-osteoporosis and early standardized joint function rehabilitation were undertaken postoperatively. The operation time and intraoperative blood loss were recorded. The range of motion of knee joint was compared before operation, at postoperative 3, 6 and 12 months and at the last follow-up. The Hospital for Special Surgery (HSS) knee score was assessed at postoperative 3, 6 and 12 months and at the last follow-up to evaluate the recovery of knee joint function. The bone mineral density was reexamined at postoperative 6 months and 12 months to evaluate the therapeutic effect of anti-osteoporosis. Complications were detected as well.Results:All patients were followed up for 12-72 months [(43.2±19.9)months]. The operation time was 90-135 minutes [(103.8±12.6)minutes], with the intraoperative blood loss of 100-250 ml [(150.0±45.6)ml]. The range of motion of knee joint was (114.6±7.8)°, (90.4±8.0)°, (97.3±4.8)° and (98.1±6.3)° before operation and at postoperative 3, 6 and 12 months (all P<0.05). The HSS knee score was (80.2±2.2)points, (84.6±2.9)points and (87.3±3.3)points at postoperative 3, 6 and 12 months (all P<0.05). The knee joint function was excellent in 10 patients and good in 3 at postoperative12 months, and the excellent and good rate was 100%. The T value of bone mineral density was (-3.8±0.6)SD, (-3.4±0.6)SD and (-2.9±0.6)SD preoperatively and at postoperative 6 months and 12 months (all P<0.05). One patient experienced nonunion and was cured after secondary autologous iliac bone grafting combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) bone grafting. Three patients developed venous thrombosis of lower limbs and were cured with oral administration of rivaroxaban. One patient had mild knee flexion and extension limitation and was improved after manual release under femoral nerve block anesthesia and subsequent functional rehabilitation. Conclusion:For patients with Rorabeck type II PDFF after TKA, single locked-plate internal fixation combined with autologous iliac bone graft has advantages of short operation time, few intraoperative bleeding, satisfactory knee range of motion and functional recovery as well as significant improvement of bone mineral density.