292 research outputs found
Recent trends, technical concepts and components of computer-assisted orthopedic surgery systems: A comprehensive review
Computer-assisted orthopedic surgery (CAOS) systems have become one of the most important and challenging types of system in clinical orthopedics, as they enable precise treatment of musculoskeletal diseases, employing modern clinical navigation systems and surgical tools. This paper brings a comprehensive review of recent trends and possibilities of CAOS systems. There are three types of the surgical planning systems, including: systems based on the volumetric images (computer tomography (CT), magnetic resonance imaging (MRI) or ultrasound images), further systems utilize either 2D or 3D fluoroscopic images, and the last one utilizes the kinetic information about the joints and morphological information about the target bones. This complex review is focused on three fundamental aspects of CAOS systems: their essential components, types of CAOS systems, and mechanical tools used in CAOS systems. In this review, we also outline the possibilities for using ultrasound computer-assisted orthopedic surgery (UCAOS) systems as an alternative to conventionally used CAOS systems.Web of Science1923art. no. 519
Augmented Reality: Mapping Methods and Tools for Enhancing the Human Role in Healthcare HMI
Background: Augmented Reality (AR) represents an innovative technology to improve data visualization and strengthen the human perception. Among Human–Machine Interaction (HMI), medicine can benefit most from the adoption of these digital technologies. In this perspective, the literature on orthopedic surgery techniques based on AR was evaluated, focusing on identifying the limitations and challenges of AR-based healthcare applications, to support the research and the development of further studies. Methods: Studies published from January 2018 to December 2021 were analyzed after a comprehensive search on PubMed, Google Scholar, Scopus, IEEE Xplore, Science Direct, and Wiley Online Library databases. In order to improve the review reporting, the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were used. Results: Authors selected sixty-two articles meeting the inclusion criteria, which were categorized according to the purpose of the study (intraoperative, training, rehabilitation) and according to the surgical procedure used. Conclusions: AR has the potential to improve orthopedic training and practice by providing an increasingly human-centered clinical approach. Further research can be addressed by this review to cover problems related to hardware limitations, lack of accurate registration and tracking systems, and absence of security protocols
Surgical implant and tissue interface
Stability of implant-tissue interface is vital for implant integration with adjacent tissue and it influences directly short- and long-term surgical outcome. The literature provides comprehensive research on implants engaged in soft as well as in hard tissues. Various factors have been found to significantly influence the interface stability. This comprehensive work incorporated several research projects with main focus on implant-tissue interface stability, which was evaluated using biomechanical assessment tools such as pullout, four-point bending as well as reverse torque test. Implants were evaluated under ex vivo conditions, immediately after being placed within tissue as well as under in vivo conditions, 2- and 6-months following the implantation surgery in goat and equine animal model. Several viewpoints of implant - tissue interface have been addressed in the following studies. Stability of the interface has been found to be primarily influenced by amount of load experienced by the implants, stress applied to adjacent tissue as well as bioactive coatings. The following studies offer novel technologies which improved implant - tissue interface stability and significantly enhanced tissue regeneration. These technologies include novel design laryngeal clamps and novel technology polyurethane scaffolds coated with bioactive nanophase Hydroxyapatite. Projects included in this dissertation concern stresses applied by the suture to adjacent laryngeal cartilage or collateral ligaments, enthesis restoration using commercially available suture anchors, as well as stability of suture anchor and stainless-steel screw within bone tissue under different loading conditions. The final chapters concern integration of tissue scaffold coated bioactive agents.Research incorporated in this work found that increased tissue and implant contact area resulted in increased interface stability and better osseointegration. Further, osseointegration process varied between each screw used to fix dynamic compression plate to bone varied. Bioactive coatings such as nanophase Hydroxyapatite were found to significantly enhance osseointegration of bone scaffolds and resulted in significantly enhanced bone regeneration
Radiation-free imaging for distal hole targeting in Intramedullary nailing
Orthopedic surgeons are routinely faced with long-bone fractures. Their preferred surgical procedure for dealing with such cases is Intra-Medullary Nailing (IMN). The aforementioned surgery usually involves alignment of the fractured fragments of the long-bone followed by the insertion of a nail down its medullary canal. To prevent displacement of bone fragments, locking screws are inserted through the proximal and distal bone fragments into holes located at the proximal and distal regions of the nail. The most challenging part of IMN surgery is the location of the two distal holes of the nail after insertion, termed distal hole targeting. To find the exact location of the distal holes, several methods have been developed. The most popular method is the free-hand technique which involves the acquisition of radiographic images of the bone and nail to find the holes.
The objective of this thesis is to review the current state of the art regarding distal hole targeting and investigate the possibility of developing an alternative imaging technique for finding the distal holes that will be free of ionizing radiation. More specifically, this work concentrates on characterizing the suitability of Earth’s Field Nuclear Magnetic Resonance (EFNMR) for this particular application. The characterization of this imaging method is performed through a series of experiments. The investigated solution poses several major challenges like contrast between different regions, time consumption, and detecting NMR signals in less than 19 ml water volume. The first two problems are resolved by using a contrast agent, Copper (II) Sulfate (CuSO4), which decreases the relaxation time by 6-7 times. In effect, this has decreased the experimental time. For instance, the experimental time was reduced from 8.32 min to 1.36 min. For the third challenge where the target is to detect the signal for 1.8 ml, all the proposed solutions have not worked as expected
Translational Models for Advancement of Regenerative Medicine and Tissue Engineering
At the root of each regenerative medicine or tissue engineering breakthrough is a simple goal, to improve quality of healing, thus improving a patient’s quality of life. Each tissue presents its own complexities and limitations to healing, whether it is the scarring nature of tendon healing or the mechanical complexity driving bone regeneration. Preclinical, translational models aim to reflect these complexities and limitations, allowing for effective development and refinement of tissue engineered therapeutics for human use. The following body of work explores several of these translational models, both utilizing them for tissue regenerative therapy development and evaluating the benefits and complications incurred with each model. This work begins with a discussion of the complexity of bone healing and how dysfunction in the mechanical, surgical, and systemic fracture environment can lead to delayed healing and nonunion. A comprehensive review of the advances in preventative and corrective therapeutics for bone nonunion is included next, with specific focuses on mechanical and tissue-engineered technology. Then, this work presents a tissue-engineered application of mesenchymal stem cells in acute tendon injury, highlighting experimentation in cell fate direction in vitro and intralesional mesenchymal stem cell implantation in vivo. Next, this work presents a series of experiments that evaluated and refined a commonly utilized preclinical model of delayed bone healing, the caprine segmental tibial defect stabilized using single locking plate fixation. First, the biomechanical stability of the model was evaluated in vivo using plantar-pressure analysis of gait. Then, the surgical technique was refined through a retrospective analysis of the effects of plate length and position on fixation stability in vitro and in vivo. Finally, the comorbidities of this preclinical model were explored via an analysis of the effect of long-term tibial locking plate fixation on cortical dimensions and density
Virtual Reality Based Environment for Orthopedic Surgery (Veos)
The traditional way of teaching surgery involves students observing a �live� surgery and then gradually assisting experienced surgeons. The creation of a Virtual Reality environment for orthopedic surgery (VEOS) can be beneficial in improving the quality of training while decreasing the time needed for training. Developing such virtual environments for educational and training purposes can supplement existing approaches. In this research, the design and development of a virtual reality based environment for orthopedic surgery is described. The scope of the simulation environment is restricted to an orthopedic surgery process known as Less Invasive Stabilization System (LISS) surgery. The primary knowledge source for the LISS surgical process was Miguel A. Pirela-Cruz (Head of Orthopedic Surgery and Rehabilitation, Texas Tech University Health Sciences Center (TTHSC)). The VEOS was designed and developed on a PC based platform. The developed VEOS was validated through interactions with surgical residents at TTHSC. Feedback from residents and our collaborator Miguel A. Pirela-Cruz was used to make necessary modifications to the surgical environment.Industrial Engineering & Managemen
Optimization of computer-assisted intraoperative guidance for complex oncological procedures
Mención Internacional en el título de doctorThe role of technology inside the operating room is constantly increasing, allowing surgical procedures previously considered impossible or too risky due to their complexity or limited access. These reliable tools have improved surgical efficiency and safety. Cancer treatment is one of the surgical specialties that has benefited most from these techniques due to its high incidence and the accuracy required for tumor resections with conservative approaches and clear margins.
However, in many cases, introducing these technologies into surgical scenarios is expensive and entails complex setups that are obtrusive, invasive, and increase the operative time. In this thesis, we proposed convenient, accessible, reliable, and non-invasive solutions for two highly complex regions for tumor resection surgeries: pelvis and head and neck. We explored how the introduction of 3D printing, surgical navigation, and augmented reality in these scenarios provided high intraoperative precision.
First, we presented a less invasive setup for osteotomy guidance in pelvic tumor resections based on small patient-specific instruments (PSIs) fabricated with a desktop 3D printer at a low cost. We evaluated their accuracy in a cadaveric study, following a realistic workflow, and obtained similar results to previous studies with more invasive setups. We also identified the ilium as the region more prone to errors.
Then, we proposed surgical navigation using these small PSIs for image-to-patient registration. Artificial landmarks included in the PSIs substitute the anatomical landmarks and the bone surface commonly used for this step, which require additional bone exposure and is, therefore, more invasive. We also presented an alternative and more convenient installation of the dynamic reference frame used to track the patient movements in surgical navigation. The reference frame is inserted in a socket included in the PSIs and can be attached and detached without losing precision and simplifying the installation. We validated the setup in a cadaveric study, evaluating the accuracy and finding the optimal PSI configuration in the three most common scenarios for pelvic tumor resection. The results demonstrated high accuracy, where the main source of error was again incorrect placements of PSIs in regular and homogeneous regions such as the ilium.
The main limitation of PSIs is the guidance error resulting from incorrect placements. To overcome this issue, we proposed augmented reality as a tool to guide PSI installation in the patient’s bone. We developed an application for smartphones and HoloLens 2 that displays the correct position intraoperatively. We measured the placement errors in a conventional and a realistic phantom, including a silicone layer to simulate tissue. The results demonstrated a significant reduction of errors with augmented reality compared to freehand placement, ensuring an installation of the PSI close to the target area.
Finally, we proposed three setups for surgical navigation in palate tumor resections, using optical trackers and augmented reality. The tracking tools for the patient and surgical instruments were fabricated with low-cost desktop 3D printers and designed to provide less invasive setups compared to previous solutions. All setups presented similar results with high accuracy when tested in a 3D-printed patient-specific phantom. They were then validated in the real surgical case, and one of the solutions was applied for intraoperative guidance. Postoperative results demonstrated high navigation accuracy, obtaining optimal surgical outcomes. The proposed solution enabled a conservative surgical approach with a less invasive navigation setup.
To conclude, in this thesis we have proposed new setups for intraoperative navigation in two complex surgical scenarios for tumor resection. We analyzed their navigation precision, defining the optimal configurations to ensure accuracy. With this, we have demonstrated that computer-assisted surgery techniques can be integrated into the surgical workflow with accessible and non-invasive setups. These results are a step further towards optimizing the procedures and continue improving surgical outcomes in complex surgical scenarios.Programa de Doctorado en Ciencia y Tecnología Biomédica por la Universidad Carlos III de MadridPresidente: Raúl San José Estépar.- Secretario: Alba González Álvarez.- Vocal: Simon Droui
The Development of a Porcine Model to Evaluate Wound Healing and Infection of Transcutaneous Osseointegrated Weight-Bearing Prostheses
Clinical studies have shown that up to 73.9% of the 1.04 million US lower limb amputees report skin problems such as sweating, irritation, and sores associated with their conventional prosthesis. An alternative option redirects ambulatory forces back to the skeleton using an implant that permanently protrudes through the skin (transcutaneous) to enable direct bone anchorage (osseointegration) of a prosthesis. Transcutaneous osseointegrated prostheses show a marked improvement in amputee acceptance over conventional prostheses. Advantages include limited tissue breakdown, a non-restricted range of motion, and enhanced functionality. However this prosthetic option has not been clinically implemented in the United States because of infection concerns and an incomplete understanding of transcutaneous wound healing. Being a potential state-of-the-art altering surgical option for trauma-induced amputees, transcutaneous osseointegration will require preliminary animal studies. To evaluate the efficacy of the transcutaneous osseointegrated option, a physiologically- similar, axially-loaded, weight bearing animal model was developed. Two pigs were fit with transcutaneous osseointegrated prostheses in a single-stage amputation and implantation surgical procedure. Clinical, microbiological, and histological data were examined to assess wound healing and infection at the skin-bone-implant interface. The animals achieved 70% and 67% pre-operative weight-bearing. Bacterial cultures indicated a likely deep tissue infection in one of the two animals. The transcutaneous wounds were in the proliferative phase of wound healing by the end of the 35 and 56 day studies. The epithelial skin layer was migrating towards the implant in one animal. Results obtained from the animal model will be used to implement future topographical and material changes at the transcutaneous site. The porcine model should become the standard for implementing and testing future iterations of weight-bearing transcutaneous osseointegrated prosthetic devices
The of Application of 3D-Printing to Lumbar Spine Surgery
Rapid prototyping refers to the manufacturing process in which a three-dimensional (3D) digital model can be transformed into a physical model by layering material in the shape of successive cross sections atop of previously layers. Rapid prototyping has been increasing in popularity in the field of medicine and surgery due to the ability to personalize various aspects of patient care. The thesis will explore the use of rapid prototyping in lumbar spine surgery, aim to quantify the accuracy of medical imaging when relating to imaged structures and their corresponding models produced by rapid prototyping, and determine if complex patient-specific guides are accurate and safe
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