Fifteen Year Outcome of the Ceraver Hermes Posterior-Stabilized Total Knee Arthroplasty: Safety of the Procedure with Experienced and Inexperienced Surgeons

We wished to determine whether total knee replacement (TKA) performed by young surgeons increased rates of mortality and complications compared with TKA performed by senior surgeons using the same model of arthroplasty. There were no significant pre-operative differences between the groups in terms of age, gender, height, weight, body mass index, diagnosis, comorbidity and duration of follow-up, which was a mean of 15 years in both groups. Hence, we assessed the 15 year survival of the first 150 Ceraver Posterior-Stabilized total knee arthroplasties undertaken by young surgeons (aged of less than 30 years) in formation in a single university hospital setting (Group B). We used survival curve analysis, with strict definitions regarding end-points, and evaluated a number of different endpoint criteria to assess the outcome and to compare the results with those obtained by the two seniors (aged of more than 40 years) with their 50 first implantations (Group A). The clinical results and survival rate of implants at intermediate to long-term follow-up were similar in both Groups. Kaplan-Meier survival analysis, with revision as the endpoint for failure, showed that the rate of survival at ten years was 96% (95% CI, 93 to 100) in both groups. At fifteen years the rate of survival was 91% (95% CI, 85 to 97) in group B, and 92% (95% CI, 90 to 94) in group A. The implant used in this series appears particularly safe since the usual complications observed with posterior stabilized arthroplasties were not observed even with young surgeons

Two stage fracture of a polyethylene post in a 9-year-old posterior-stabilized knee prosthesis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Several cases of tibial post breakage are reported in the literature. To the best of our knowledge, only three cases of NexGen knee prosthesis (Zimmer, Warsaw, Indiana, USA) tibial post failure have been reported.</p> <p>Case presentation</p> <p>In November 1999, a 63-year-old Caucasian woman from Italy with a history of symptomatic left knee osteoarthritis underwent a total knee arthroplasty. In March 2008, while rising from a chair, she felt a sudden pain and instability in her left knee. She reported a fracture of the polyethylene post of the tibial insert. No malposition or malalignment of either the femoral or tibial components were identified. The polyethylene tibial insert was studied under light microscopy and scanning electron microscopy. The fracture was also noted to have occurred without any notable polyethylene wear.</p> <p>Conclusion</p> <p>Scanning electron microscopy revealed two different damage patterns that could be explained with a two-stage rupture of our patient's polyethylene post. This could have been caused by a non-optimal ligamentous balancing during first implant surgery. Her knee probably developed a varus instability that weakened the post, and then a posterior anterior stress finally broke the polyethylene.</p

Polyethylene thickness is a risk factor for wear necessitating insert exchange

PURPOSE: The aim of this observational study was to investigate the optimal minimal polyethylene (PE) thickness in total knee arthroplasty (TKA) and identify other risk factors associated with revision of the insert due to wear. METHODS: A total of 84 TKA were followed for 11-16 years. All patients received the same prosthesis design (Interax; Howmedica/ Stryker) with halfbearings: separate PE-inserts medially and laterally. Statistical analysis comprised Cox-regression to correct for confounding. RESULTS: Eight knees (9.5%) had been revised due to thinning inserts and an additional patient is scheduled for revision. PE thickness, diagnosis, BMI and weight are risk factors for insert exchange. For each millimetre decrease in PE thickness, the risk of insert exchange increases 3.0 times, which remains after correction for age, gender, weight, diagnosis and femoral-tibial angle. Insert exchange was 4.73 times more likely in OA-patients compared to RA-patients. For every unit increase in BMI and weight the risk for insert exchange increases 1.40 times and 1.14 times, respectively. CONCLUSIONS: In conclusion we therefore advise against the use of thin PE inserts in modular TKA and recommend PE inserts with a minimal 8-mm thickness.Optimising joint reconstruction management in arthritis and bone tumour patient

Metal on metal hip resurfacing versus uncemented custom total hip replacement - early results

<p>Abstract</p> <p>Introduction</p> <p>There is no current consensus on the most appropriate prosthesis for treating symptomatic osteoarthritis (OA) of the hip in young, active patients. Modern metal on metal hip resurfacing arthroplasty (HR) has gained popularity as it is theoretically more stable, bone conserving and easier to revise than total hip arthroplasty. Early results of metal on metal resurfacing have been encouraging. We have compared two well matched cohorts of patients with regard to function, pain relief and patient satisfaction.</p> <p>Methods</p> <p>This prospective study compares 2 cohorts of young, active patients treated with hip resurfacing (137 patients, 141 hips) and custom uncemented (CADCAM) stems (134 patients, 141 hips). All procedures were performed by a single surgeon. Outcome measures included Oxford, WOMAC and Harris hip scores as well as an activity score. Statistical analysis was performed using the unpaired student's t-test.</p> <p>Results</p> <p>One hundred and thirty four and 137 patients were included in the hip replacement and resurfacing groups respectively. The mean age of these patients was 54.6 years. The mean duration of follow up for the hip resurfacing group was 19.2 months compared to 13.4 months for the total hip replacement group.</p> <p>Pre operative oxford, Harris and WOMAC scores in the THA group were 41.1, 46.4 and 50.9 respectively while the post operative scores were 14.8, 95.8 and 5.0. In the HR group, pre- operative scores were 37.0, 54.1 and 45.9 respectively compared to 15.0, 96.8 and 6.1 post operatively. The degree of improvement was similar in both groups.</p> <p>Conclusion</p> <p>There was no significant clinical difference between the patients treated with hip resurfacing and total hip arthroplasty in the short term.</p

Positive nasal culture of methicillin-resistant Staphylococcus aureus (MRSA) is a risk factor for surgical site infection in orthopedics

Background Although nasal carriage of MRSA has been identified as one of the risk factors for surgical site infection (SSI) with MRSA, there have been no reports of this in the orthopedics field

Bone and joint infections in adults: a comprehensive classification proposal

Ten currently available classifications were tested for their ability to describe a continuous cohort of 300 adult patients affected by bone and joint infections. Each classification only focused, on the average, on 1.3\u2009\ub1\u20090.4 features of a single clinical condition (osteomyelitis, implant-related infections, or septic arthritis), being able to classify 34.8\u2009\ub1\u200924.7% of the patients, while a comprehensive classification system could describe all the patients considered in the study. RESULT AND CONCLUSION: A comprehensive classification system permits more accurate classification of bone and joint infections in adults than any single classification available and may serve for didactic, scientific, and clinical purposes

Physical and sports activity after hip arthroplasty

A artroplastia é utilizada para reconstrução da articulação do quadril, visando minimizar a dor e possibilitar o retorno às atividades de vida diária, esportivas e de lazer. O objetivo deste artigo é analisar na literatura as indicações e contraindicações referentes à prática de atividade física, esportiva e lazer após a artroplastia de quadril. Essa revisão aborda estudos publicados entre os anos de 1980 e 2009, obtidos por buscas em bancos de dados eletrônicos Medline, Scielo, Ovid, Infomaworld, Sciencedirect, Springerlink, Interscience, Sportdiscuss, Bireme, Informglobal, Opas, Ovid, Diseasedex, Eric, que totalizaram 39 artigos. Os artigos analisados apontam para a utilização de atividade física, esportiva e de lazer de baixo impacto. como a caminhada, natação, boliche, ciclismo, dentre outras. Outra indicação constatada na literatura é a utilização da atividade física e esportiva visando à manutenção do condicionamento físico, qualidade óssea e controle do peso corporal. Há ressalvas na literatura sobre a utilização de atividades de alto impacto, esporte com giro como o basquete e futebol ou com grande intensidade como tênis e a corrida, bem como os esportes de luta. As atividades físicas, esportivas e de lazer mais indicadas após uma atroplastia de quadril são as de baixo impacto como a hidroginástica, natação, caminhada, dentre outras. O início dessas atividades deve aguardar a liberação do médico, mas em média iniciam 60 dias após a cirurgia.Hip arthroplasty is used for reconstruction of the hip joint to reduce pain and to make the return to daily life, physical, sports and leisure activities possible. The objective of this article was to analyze in the literature the indications and counter-indications referring to practice of physical, sportive and leisure activities after hip arthroplasty. This revision approaches studies published between 1980 and 2009, obtained in searches in the Medline, Scielo, Ovid, Infomaworld, Sciencedirect, Springerlink, Interscience, Sportdiscuss, Bireme, Informglobal, Opas, Ovid, Diseasedex and Erics electronic databases with a total of 39 articles. The analyzed articles point to the use of physical, leisure and sports of low impact activities such as walking, swimming, bowling, cycling and others. Another indication evidenced in the literature is the use of physical and sportive activity aiming at the maintenance of physical fitness, bone quality and body weight control. The literature shows concerns with the use of activities of high impact or with great intensity like tennis and jogging, as well as fights