50 research outputs found

    Computer-aided detection in musculoskeletal projection radiography: A systematic review

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    This is the author accepted manuscript. The final version is available from WB Saunders via the DOI in this record.Objectives To investigated the accuracy of computer-aided detection (CAD) software in musculoskeletal projection radiography via a systematic review. Key findings Following selection screening, eligible studies were assessed for bias, and had their study characteristics extracted resulting in 22 studies being included. Of these 22 three studies had tested their CAD software in a clinical setting; the first study investigated vertebral fractures, reporting a sensitivity score of 69.3% with CAD, compared to 59.8% sensitivity without CAD. The second study tested dental caries diagnosis producing a sensitivity score of 68.8% and specificity of 94.1% with CAD, compared to sensitivity of 39.3% and specificity of 96.7% without CAD. The third indicated osteoporotic cases based on CAD, resulting in 100% sensitivity and 81.3% specificity. Conclusion The current evidence reported shows a lack of development into the clinical testing phase; however the research does show future promise in the variation of different CAD systems

    A Tribological assessment of the porous coated anatomic total hip replacement

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    The tribological performance of internal joint prostheses is a fundamental influence on their longevity. The aim of this study is to characterise the tribological performance of the Porous Coated Anatomic total hip replacement by the analysis of 119 explanted prostheses. Investigations of the friction, wear, surface topography and wear debris were made and related to the joint's clinical performance. The friction of the joints at explant was similar to that of new prostheses. The median total wear volume (419mm(^3)) was found to agree with previous wear studies suggesting the existence of a threshold wear volume which promotes osteolysis. Clinical wear factor for the whole cohort matched that of alternative joint designs. The femoral head finish was shown to degrade but not in proportion to implant duration. The roughness of the UHMWPE liner was shown to fall but no relationship with any head roughness, or temporal, parameter could be distinguished. Simulator studies confirmed that the wear factor of a joint is likely to change over its lifespan. Wear models published previously describing the influence of femoral head roughness on wear could not predict the performance of explanted prostheses. An alternative relationship was observed indicating that head roughness is not as powerful a predictor of wear as previously held. A novel technique for the characterisation of the size distribution of ex vivo and in vitro wear debris was developed. A Low-Angle Laser Light Scattering Particle Analyser was used to size particles continuously over a range from 0.5 to 1000μm. This technique offers considerable unprovement over existing microscope-based methods in terms of the detail of the information and does so with less experimental effort. It was shown to be highly accurate and repeatable in preliminary investigations. Case studies of five tissue samples revealed the potential of this method

    Total Disc Replacement: Periprosthetic Wear Debris and Biological Responses

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    Total disc replacement (TDR) was clinically introduced as an alternative to spinal fusion to relieve back pain, maintain mobility of the spine and eliminate the adverse side effects of fusion. More recently, gamma-inert-sterilized ultra-high molecular weight polyethylene (UHMWPE) TDR cores were introduced to replace historical gamma-air-sterilized cores in an effort to reduce UHMWPE wear debris and inflammation. In this study, both implant and periprosthetic tissue retrievals from patients with gamma-inert-sterilized TDRs were evaluated for in vivo performance and biological responses, respectively. As pain was the primary revision reason for all patients, the contributions of implant-related damage and tissue responses to the development of pain were also a focus of this investigation. After analyzing implants and tissues for 11 TDR patients, detectable UHMWPE wear debris was identified with corresponding macrophage infiltration in six patients with associated implant damage. Neither damage nor TDR bearing design, fixed vs mobile, influenced the amount, size and shape characteristics of wear particles. However, comparisons to a retrieval study of historical devices indicated that the number of UHMWPE particles generated from gamma-inert-sterilized devices were decreased by 99% (p=0.003) and were 50% rounder (p=0.003), confirming the improved wear resistance of the newer devices. Accordingly, periprosthetic tissue reactions were also substantially reduced. Prospective immunohistochemical investigations for these devices showed, for the first time, that UHMWPE wear-debris induced tissue reactions in the human lumbar spine can be linked to inflammation. First, inflammatory factors were elevated in TDR periprosthetic tissues (n=30) when compared to disc degenerative disease (DDD) patient tissues (n=3) from primary surgery and disc tissues (n=4) from normal autopsy patients with no history of lower back pain. The mean percent area of production for vascular endothelial growth factor (VEGF) (p=0.04), interleukin-1beta (IL-1[beta]), (p=0.01) and substance P (p=0.01) were significantly higher in TDR tissues when compared to tissues obtained from DDD patients. Although platelet derived growth factor-bb (PDGFbb) (p=0.14), tumor necrosis factor-alpha (TNF[alpha]) (p=0.06) and nerve growth factor (NGF) (p=0.19) were also increased in the TDR patient tissues, these increases were not significant. Compared to normal disc tissues, the mean percent area for all six factors was statistically increased in TDR tissues (at least p<0.05 for all). Interestingly, no statistical differences were observed between DDD and normal disc tissues. Next, our studies showed that TNFα, IL-1[beta], VEGF, NGF and substance P strongly correlated with the number of wear particles and also the number of macrophages for the TDR patient group (at least p<0.05 for all). Finally, the pro-inflammatory/pain factors, TNF[alpha] and IL-1[beta], and the vascularization factors, VEGF and PDGFbb, significantly correlated with the presence of the neural innervation and hypersensitization agents, NGF and substance P (p<0.01 for all). These findings suggest not only the presence of inflammatory reactions, but the presence of factors that can directly and indirectly contribute to the pain sensitivity. In addition to wear-debris and subsequent inflammation, increased vascularization was another key histomorphological change observed in the TDR tissues that may be involved in the pathogenesis of particle disease. In brief, the ingrowth of blood vessels may be providing a conduit for nociceptive innervation. Studying vascularity in revision tissues showed the total number of blood vessels was significantly associated with TNF[alpha], IL-1[beta], VEGF, PDGFbb, NGF and substance P (at least p<0.05 for all), suggesting an interrelation between vascular changes and inflammatory-mediated responses. Furthermore, analysis at the local level revealed the innervation/pain factors, NGF and substance P, were predominantly localized to vascular channels, suggestive of nerve ingrowth and potential neural-maladaptive plasticity at periprosthetic sites. Lastly, comparing blood vessel number with factor expression and macrophage number in individual images obtained from tissue sections with low and high vascularity suggested a temporal link between TNF[alpha], macrophages and angiogenesis. Taken together, elucidating the pathogenesis of inflammatory particle disease will provide information needed to identify potential therapeutic targets and treatment strategies to mitigate pain.Ph.D., Biomedical Engineering -- Drexel University, 201

    CT Scanning

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    Since its introduction in 1972, X-ray computed tomography (CT) has evolved into an essential diagnostic imaging tool for a continually increasing variety of clinical applications. The goal of this book was not simply to summarize currently available CT imaging techniques but also to provide clinical perspectives, advances in hybrid technologies, new applications other than medicine and an outlook on future developments. Major experts in this growing field contributed to this book, which is geared to radiologists, orthopedic surgeons, engineers, and clinical and basic researchers. We believe that CT scanning is an effective and essential tools in treatment planning, basic understanding of physiology, and and tackling the ever-increasing challenge of diagnosis in our society

    Novel Research about Biomechanics and Biomaterials Used in Hip, Knee and Related Joints

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    Joint replacement is a very successful medical treatment. However, the survivorship of hip, knee, shoulder, and other implants is limited. The degradation of materials and the immune response against degradation products or an altered tissue loading condition as well as infections remain key factors of their failure. Current research in biomechanics and biomaterials is trying to overcome these existing limitations. This includes new implant designs and materials, bearings concepts and tribology, kinematical concepts, surgical techniques, and anti-inflammatory and infection prevention strategies. A careful evaluation of new materials and concepts is required in order to fully assess the strengths and weaknesses and to improve the quality and outcomes of joint replacements. Therefore, extensive research and clinical trials are essential. The main aspects that are addressed in this Special Issue are related to new material, design and manufacturing considerations of implants, implant wear and its potential clinical consequence, implant fixation, infection-related material aspects, and taper-related research topics. This Special Issue gives an overview of the ongoing research in those fields. The contributions were solicited from researchers working in the fields of biomechanics, biomaterials, and bio- and tissue-engineering

    1st EFORT European Consensus: Medical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices

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    Innovations in Orthopaedics and Traumatology have contributed to the achievement of a high-quality level of care in musculoskeletal disorders and injuries over the past decades. The applications of new implants as well as diagnostic and therapeutic techniques in addition to implementation of clinical research, have significantly improved patient outcomes, reduced complication rates and length of hospital stay in many areas. However, the regulatory framework is extensive, and there is a lack of understanding and clarity in daily practice what the meaning of clinical &amp; pre‐clinical evidence as required by the MDR is. Thus, understanding and clarity are of utmost importance for introduction of new implants and implant-related instrumentation in combination with surgical technique to ensure a safe use of implants and treatment of patients. Therefore EFORT launched IPSI, The Implant and Patient Safety Initiative, which starting from an inaugural workshop in 2021 issued a set of recommendations, notably through a subsequent Delphi Process involving the National Member Societies of EFORT, European Specialty Societies as well as International Experts. These recommendations provide surgeons, researchers, implant manufacturers as well as patients and health authorities with a consensus of the development, implementation, and dissemination of innovation in the field of arthroplasty. The intended key outcomes of this 1st EFORT European Consensus on “Medical &amp; Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices”are consented, practical pathways to maintain innovation and optimisation of orthopaedic products and workflows within the boundaries of MDR 2017/745. Open Access practical guidelines based on adequate, state of the art pre-clinical and clinical evaluation methodologies for the introduction of joint replacements and implant-related instrumentation shall provide hands-on orientation for orthopaedic surgeons, research institutes and laboratories, orthopaedic device manufacturers, Notified Bodies but also for National Institutes and authorities, patient representatives and further stakeholders. We would like to acknowledge and thank the Scientific Committee members, all International Expert Delegates, the Delegates from European National &amp; Specialty Societies and the Editorial Team for their outstanding contributions and support during this EFORT European Consensus

    Tribological Performance of Artificial Joints

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    Joint replacement is a very successful medical treatment. However, the survivorship of the implants could be adversely affected due to the loss of materials in the form of particles or ions as the bearing surfaces articulate against earch other. The consequent tissue and immune response to the wear products, remain one of the key factors of their failure. Tribology has been defined as the science and technology of interacting surfaces in relative motion and all related wear products (e.g., particles, ions, etc.). Over the last few decades, in an attempt to understand and improve joint replacement technology, the tribological performance of several material combinations have been studied experimentally and assessed clinically. In addition, research has focused on the biological effects and long term consequences of wear products. Improvements have been made in manufacturing processes, precision engineering capabilities, device designs and materials properties in order to minimize wear and friction and maximize component longevity in vivo

    Osseointegrated Oral implants

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    In the past, osseointegration was regarded to be a mode of implant anchorage that simulated a simple wound healing phenomenon. Today, we have evidence that osseointegration is, in fact, a foreign body reaction that involves an immunologically derived bony demarcation of an implant to shield it off from the tissues. Marginal bone resorption around an oral implant cannot be properly understood without realizing the foreign body nature of the implant itself. Whereas the immunological response as such is positive for implant longevity, adverse immunological reactions may cause marginal bone loss in combination with combined factors. Combined factors include the hardware, clinical handling as well as patient characteristics that, even if each one of these factors only produce subliminal trauma, when acting together they may result in loss of marginal bone. The role of bacteria in the process of marginal bone loss is smaller than previously believed due to combined defense mechanisms of inflammation and immunological reactions, but if the defense is failing we may see bacterially induced marginal bone loss as well. However, problems with loss of marginal bone threatening implant survival remains relatively uncommon; we have today 10 years of clinical documentation of five different types of implant displaying a failure rate in the range of only 1 to 4 %

    Bone quality and mesenchymal stromal cell capacity in total hip replacement: Significance for stem osseointegration measured by radiostereometric analysis

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    Immediate implant stability is a key factor for success in cementless total hip arthroplasty (THA). Cementless techniques were originally designed for middle-aged patients with normal bone structure and healing capacity, but indications have expanded to also include elderly patients. Poor local bone quality, as a result of osteoporosis (OP), and age-related geometric changes of the proximal femur, may jeopardize initial implant stability and lead to increased migration of the implant components thereby compromising biological fixation and osseointegration. Mesenchymal stromal cells (MSCs) are essential in the process of osseointegration. Age-related dysfunction of MSCs is suggested to be a main contributory factor in altered bone repair with aging and therefore may influence osseointegration. The hypothesis of this prospective clinical study was that preoperative bone quality and MSC capacity dictate stability and osseointegration of femoral stems in cementless THA, especially in women after menopause. A total of 61 consecutive women (age <80 yrs) scheduled for cementless THA for primary hip osteoarthritis (OA) were screened for undiagnosed primary or secondary OP, vitamin D insufficiency and other metabolic bone diseases. Prior to THA, patients underwent aspiration of iliac crest bone marrow for analysis of MSC capacity using optimized isolation and culturing protocols. All patients received a cementless total hip implant with an anatomically designed hydroxyapatite (HA) coated femoral stem and ceramic-ceramic bearings. Per-operative biopsy of the intertrochanteric bone was taken for ex vivo analysis of the local cancellous bone quality using micro-CT imaging and biomechanical testing. After surgery, stem migration and osseointegration was monitored for two years using radiostereometric analysis. The majority of women with hip OA was osteopenic or osteoporotic. These conditions were associated with increased periprosthetic bone loss in the proximal femur and impaired initial stability and delayed osseointegration of the femoral stem. Altered intraosseous dimensions of the proximal femur, as well as aging, also had adverse effects on initial stem stability and were associated with delayed osseointegration. Local bone mineral density of the operated hip and the quality of intertrochanteric cancellous bone had less influence than expected on implant migration. The THA females showed differences in the osteogenic properties of their MSCs. Patients with MSCs of low in vitro osteogenic capacity displayed increased stem subsidence after the initial 3 months settling period and thereby delayed osseointegration. The results suggest that decreased skeletal health, such as low systemic BMD and decreased osteogenic properties of bone marrow MSCs, has major influence on early stability and osseointegration of cementless hip prostheses in female patients.Luun laadun ja mesenkymaalisten kantasolujen toiminnan vaikutus lonkan tekonivelen paranemiseen Tekonivelleikkaus on erinomainen toimenpide lonkan nivelrikon hoidossa. Jos leikkausmenetelmäksi valitaan biologisesti kiinnittyvä tekonivel, olennaisinta on saavuttaa komponenttien välitön stabiliteetti. Se mahdollistaa uudisluun kasvun implantin karhennetulle pinnalle. Ikääntymiseen liittyvä luuston haurastuminen ja reisiluun yläosan ydinontelon laajentuminen voivat heikentää tekonivelen komponenttien tukevuutta ja näin hidastaa niiden kiinnittymistä luuhun. Tällainen on mahdollista erityisesti naisilla vaihdevuosien jälkeen. Näiden potilaiden yksilölliset erot luun parantavien solujen (mesenkymaalisten kantasolujen) määrässä ja toiminnassa voivat osaltaan vaikuttaa heidän tekoniveltensä kiinnittymisnopeuteen. Tähän prospektiiviseen kliiniseen tutkimukseen osallistui 61 naispotilasta, joille tehtiin sementöimätön lonkan tekonivelleikkaus nivelrikon takia. Ennen leikkausta potilaille tehtiin seulontatutkimukset osteoporoosin ja muiden luuston aineenvaihduntasairauksien tunnistamiseksi. Leikkauksen yhteydessä potilailta otettiin luuydinnäyte suoliluusta, josta analysoitiin mesenkymaalisten kantasolujen jakautumis- ja erilaistumiskyky luunsoluiksi. Leikkauksen aikana otettiin näyte reisiluun yläosan hohkaluun hienorakenteen ja mekaanisten ominaisuuksien arvioimiseksi. Leikkauksen jälkeen tekonivelen reisikomponentin kolmiulotteista migraatiota ja kiinnittymistä seurattiin radiostereometrisellä analyysillä (RSA) 2 vuoden ajan. Valtaosalla potilaista oli alentunut luuntiheys (osteopenia tai osteoporoosi). Osteopeenisillä ja osteoporoottisilla potilailla todettiin kiihtynyttä luukatoa tekonivelen reisikomponentin ympärillä sekä komponentin lisääntynyttä migraatiota ja hidastunutta kiinnittymistä. Reisiluun yläosan ydinontelon laajentuminen ja potilaan korkea ikä lisäsivät reisikomponentin migraatiota, mutta reisiluun hohkaluun laatu ei vaikuttanut migraation määrään. Potilailla, joilla todettiin mesenkymaalisten kantasolujen alentunut kyky erilaistua luusoluiksi in vitro, todettiin reisikomponentin lisääntynyttä migraatiota ja hidastunutta kiinnittymistä. Tulokset osoittavat, että ikääntymiseen liittyvät luustomuutokset ja yksilölliset erot mesenkymaalisten kantasolujen määrässä ja toiminnassa voivat osaltaan vaikuttaa lonkan tekonivelten paranemiseen naisilla vaihdevuosien jälkeen.Siirretty Doriast
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