213 research outputs found

    Computer assistance in orthopaedic surgery

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    A Novel Percutaneous Screw Fixation of Postero-lateral Tibial Plateau Fracture using Posterior Cruciate Ligament Reconstruction Femoral Template: Technical Note 使用後交叉韌帶重建股骨模板重建後外側脛骨平台骨折的一種新的經皮螺釘固定法:技術說明

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    AbstractPercutaneous fixation method has been applied in Schatzker type III joint depressed-type lateral tibial plateau fracture. We report a 76-year-old man suffering from a small joint depressed-type posterolateral tibial plateau fracture with surgical reduction and fixation with a novel guidance of posterior cruciate ligament (PCL) reconstruction femoral template under X-ray and arthroscopic assistance. The concept of sequential tunnel drilling in ligament reconstruction has been applied in bone impaction tunnel creation beneath the articular step with the PCL jig. Avoidance of multiple bone guide pin drilling and accurate guide pin insertion and hence screw fixation was also achieved by use of the PCL template. As illustrated, we believe that the PCL jig is a good armamentarium and adjunct equipment to achieve a more precise minimally invasive operation in special anatomical positions such as the postero-lateral tibial plateau under careful surgical planning

    Novel Insights into Anterior Cruciate Ligament Injury

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    Anterior cruciate ligament (ACL) injury is one of the most common sports injuries of the knee. ACL reconstruction has become, standard orthopaedic practice worldwide with an estimated 175,000 reconstructions per year in the United States.6 The ACL remains the most frequently studied ligament in orthopaedic research. Hundreds of papers are published each year related to the ACL. However, the treatment options and techniques are still developing and increasing, indicating the difficulties in the treatment of this central knee ligament

    Aligning 3D Curve with Surface Using Tangent and Normal Vectors for Computer-Assisted Orthopedic Surgery

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    Registration that aligns different views of one interested organ together is an essential technique and outstanding problem in medical robotics and image-guided surgery (IGS). This work introduces a novel rigid point set registration (PSR) approach that aims to accurately map the pre-operative space with the intra-operative space to enable successful image guidance for computer-assisted orthopaedic surgery (CAOS). The normal vectors and tangent vectors are first extracted from the pre-operative and intra-operative point sets (PSs) respectively, and are further utilized to enhance the registration accuracy and robustness. The contributions of this article are three-folds. First, we propose and formulate a novel distribution that describes the error between one normal vector and the corresponding tangent vector based on the von-Mises Fisher (vMF) distribution. Second, by modelling the anisotropic position localization error with the multi-variate Gaussian distribution, we formulate the PSR considering anisotropic localization error as a maximum likelihood estimation (MLE) problem and then solve it under the expectation maximization (EM) framework. Third, to facilitate the optimization process, the gradients of the objective function with respect to the desired parameters are computed and presented. Extensive experimental results on the human femur and pelvis models verify that the proposed approach outperforms the state-of-the-art methods, and demonstrate potential clinical values for relevant surgical navigation applications

    Application of 3D imaging technology to anterior cruciate ligament surgery

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    Includes bibliographical references (leaves 155-160)

    Development and Assessment of a Micro-CT Based System for Quantifying Loaded Knee Joint Kinematics and Tissue Mechanics

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    Although anterior cruciate ligament (ACL) reconstruction is a highly developed surgical procedure, sub-optimal treatment outcomes persist. This can be partially attributed to an incomplete understanding of knee joint kinematics and regional tissue mechanic properties. A system for minimally-invasive investigation of knee joint kinematics and tissue mechanics under clinically relevant joint loads was developed to address this gap in understanding. A five degree-of-freedom knee joint motion simulator capable of dynamically loading intact human cadaveric knee joints to within 1% of user defined multi-axial target loads was developed. This simulator was uniquely designed to apply joint loads to a joint centered within the field of view of a micro-CT scanner. The use of micro-CT imaging and tissue-embedded radiopaque beads demonstrated high-resolution strain measurement, distinguishing differences in inter-bead distances as low as 0.007 mm. Inter-bead strain measurement was highly accurate and repeatable, with no significant error introduced from cyclic joint loading. Finally, regional strain was repeatably measured using radiopaque markers in four intact, human cadaveric knees to within 0.003 strain in response to multi-directional joint loads. This novel combination of dynamic knee joint motion simulation, tissue-embedded radiopaque markers, and micro-CT imaging provides the opportunity to increase our understanding of the kinematics and tissue mechanics of the knee, with the potential to improve ACL reconstruction outcomes

    Personalized Hip and Knee Joint Replacement

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    This open access book describes and illustrates the surgical techniques, implants, and technologies used for the purpose of personalized implantation of hip and knee components. This new and flourishing treatment philosophy offers important benefits over conventional systematic techniques, including component positioning appropriate to individual anatomy, improved surgical reproducibility and prosthetic performance, and a reduction in complications. The techniques described in the book aim to reproduce patients’ native anatomy and physiological joint laxity, thereby improving the prosthetic hip/knee kinematics and functional outcomes in the quest of the forgotten joint. They include kinematically aligned total knee/total hip arthroplasty, partial knee replacement, and hip resurfacing. The relevance of available and emerging technological tools for these personalized approaches is also explained, with coverage of, for example, robotics, computer-assisted surgery, and augmented reality. Contributions from surgeons who are considered world leaders in diverse fields of this novel surgical philosophy make this open access book will invaluable to a wide readership, from trainees at all levels to consultants practicing lower limb surger

    Functional Outcomes of Anterior Cruciate Ligament Reconstruction Surgery

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    Anterior cruciate ligament (ACL) is one of the most common sports injuries with a reported yearly incidence rate of over two million injuries worldwide. The main aim of this thesis is to investigate various aspects related to the functional outcomes of ACLR through a series of clinical studies. Ethical approval was sought and granted by the North of Scotland Research Ethics Service. A systematic review was conducted to investigate the outcome measures used in Level I and II clinical ACLR studies. The review showed wide variability in the outcome measures utilised with no consensus on the ideal outcome instrument or combination of instruments to report the outcome of ACLR. Five-year results from the UK National Ligament Registry (NLR) were analysed with review for limitations of registry data and future recommendations. The data analysed provided a comprehensive review for the demographics, surgical techniques and functional outcomes of ACLR surgery across the UK. NLR data is limited by multiple factors including high rate of incomplete data, duplication of data, poor patient compliance and lack of validation of the data. A study was conducted to examine the hypothesis that patients with ACLR do not return to their pre-injury functional status at two years postoperatively. The study showed significant improvement in patient symptoms postoperatively compare to their post-injury scores, but the majority of patients failed to achieve their pre-injury functional outcome scores at 2 years postoperatively. In a comparative study, the anteromedial portal (AM) technique in femoral tunnel drilling was compared with the trans-tibial (TT) technique with respect to radiological and functional outcomes. The hypothesis was that AM portal produces better functional outcomes compared with TT technique. We found that the AM portal achieved a more anatomical position of the graft but there was no difference between the two techniques in functional outcome at 2 years postoperatively. However, ACLR with the AM portal technique had higher graft failure rate compared with the TT technique. The medium- term outcome of all-inside meniscal repairs was investigated in a longitudinal study. Meniscal repairs with concomitant ACLR had a lower failure rate compared with isolated meniscal repairs. This indicates that surgeons should have a low threshold for repairing meniscal tear during ACLR surgery. The healing response technique was studied in a selected group of patients with complete proximal ACL tears. This technique yielded good functional outcome for most of the patients at 2 years postoperative follow up. The studies included in this thesis provides substantial information for surgeons treating patients with ACL injuries. It provides a platform for further research studies investigating the outcomes of ACLR surgery
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