A Critical Review of the Design, Manufacture, and Evaluation of Bone Joint Replacements for Bone Repair

With the change of people’s living habits, bone trauma has become a common clinical disease. A large number of bone joint replacements is performed every year around the world. Bone joint replacement is a major approach for restoring the functionalities of human joints caused by bone traumas or some chronic bone diseases. However, the current bone joint replacement products still cannot meet the increasing demands and there is still room to increase the performance of the current products. The structural design of the implant is crucial because the performance of the implant relies heavily on its geometry and microarchitecture. Bionic design learning from the natural structure is widely used. With the progress of technology, machine learning can be used to optimize the structure of bone implants, which may become the focus of research in the future. In addition, the optimization of the microstructure of bone implants also has an important impact on its performance. The widely used design algorithm for the optimization of bone joint replacements is reviewed in the present study. Regarding the manufacturing of the implant, the emerging additive manufacturing technique provides more room for the design of complex microstructures. The additive manufacturing technique has enabled the production of bone joint replacements with more complex internal structures, which makes the design process more convenient. Numerical modeling plays an important role in the evaluation of the performance of an implant. For example, theoretical and numerical analysis can be carried out by establishing a musculoskeletal model to prepare for the practical use of bone implants. Besides, the in vitro and in vivo testing can provide mechanical properties of bone implants that are more in line with the implant recipient’s situation. In the present study, the progress of the design, manufacture, and evaluation of the orthopedic implant, especially the joint replacement, is critically reviewed.

What’s New in Hip Replacement- Recent Update and Guidelines

Hip replacement surgery has undergone tremendous changes from preoperative work up to post operative management. Now many studies are done on individual stages to assess which is the best method. Also, these are helping to fasten the recovery phase. Early and pain free mobilisation is the present motto in joint replacements so that patients can get back to their routine activities as soon as possible.

Smart surgical template models for customized knee joint replacements

The paper introduces a method for the automated generation of patient-specific instruments (PSI), here in particular templates, for the implantation of customized implants. The basis is the derivation of data from the morphology of the bony situation and the medical planning. A developed methodological approach based on an Active Shape Model (ASM) is used for the morphological measurement. Determined geometric dimensions are placed on this ASM and automatically adjusted in each case. In addition, specially developed software tools for the planning and design of medical devices will be presented. This includes, among other things, the intuitive control of template parameters by the user when manual adjustments are necessary. The determined data is bundled and applied to previously methodically thought-out and categorized master CAD (Computer Aided Design) models of surgical templates. These master models are fully configurable and designed to be adjusted within defined ranges of values. The templates are printed from the biocompatible material PA12 using selective laser sintering (SLS).

1159 Ring-Fenced Arthroplasty Unit: The Need of The Hour During Winter and A Pandemic Crisis

Aim Winter pressures along with the COVID-19 pandemic, have caused cancellation of elective services, prolonged waiting times, patient dissatisfaction and financial implications. Length of stay (LOS) following joint replacements is variable. The availability of ring-fenced beds and enhanced recovery protocol (ERP) can improve these outcomes. The performance of a stand-alone arthroplasty unit in an acute NHS Trust was assessed regarding safety, LOS and complications. Method Patient data was collected for total hip & knee replacements (TJAs) between the months of December to March of 2018-19 and 2019-20. Demographics, ASA, transfusion rates, LOS and 90-day reattendance was analysed. Modified ERP implemented in late 2019 included changes in analgesia and early post-operative mobilisation. The performance was then compared with DGHs within the region. Results In 2019-20, of 280 TJAs performed, there was a mean LOS of 43 hours. This shows a reduction compared with LOS of 69 hours in 2018-19, where 288 TJAs were performed. In 2019-20, 74% of cases had early discharge within 36 hours of surgery, versus 24% in 2018-19. This accumulates to 333 inpatient days saved. Note that following ERP modification, 6 patients were discharged on the day of surgery. Surgery related complications within 3 months which required reattendance, were seen in only 2 patients. This unit performed an average of 335 TJA’s in these winter months, the highest average in comparison to other DGHs in the East Midlands region, which had an overall average of 165 cases. Conclusions A ring-fenced arthroplasty service with adherence to ERP significantly decreases LOS and increases productivity.

The impact of first and second wave of COVID-19 on knee and hip surgeries in Sweden

Purpose To investigate the impact of COVID-19 in Sweden on rates of knee and hip surgeries. Methods We used healthcare data for the population of the southernmost region in Sweden (1.4 million inhabitants). We did an interrupted time-series analysis to estimate changes in rates and trends of joint replacements (JR), arthroscopies, and fracture surgeries for knee or hip in April–December 2020 compared to pre-COVID-19 levels adjusting for seasonal variations. Results We found a drop of 54% (95% CI 42%; 68%) and 42% (95% CI 32%; 52%), respectively, in the rate of JRs and arthroscopies in April 2020 when compared to the counterfactual scenario. This was followed by an increase that brought the rates of JRs and arthroscopies back to their predicted levels also during the beginning of the second wave (November–December 2020). Acute fracture surgeries were largely unaffected, i.e. did not show any decrease as observed for the other surgeries. Conclusions In southern Sweden, we observed a marked decrease in elective knee and hip surgeries following the first wave of Covid-19. The rates remained close to normal during the beginning of the second wave suggesting that important elective surgeries for patients with end-stage osteoarthritis can still be offered despite an ongoing pandemic provided adequate routines and hospital resources.

Instrumental Validity of the Motion Detection Accuracy of a Smartphone-Based Training Game

Demographic changes associated with an expanding and aging population will lead to an increasing number of orthopedic surgeries, such as joint replacements. To support patients’ home exercise programs after total hip replacement and completing subsequent inpatient rehabilitation, a low-cost, smartphone-based augmented reality training game (TG) was developed. To evaluate its motion detection accuracy, data from 30 healthy participants were recorded while using the TG. A 3D motion analysis system served as reference. The TG showed differences of 18.03 mm to 24.98 mm along the anatomical axes. Surveying the main movement direction of the implemented exercises (squats, step-ups, side-steps), differences between 10.13 mm to 24.59 mm were measured. In summary, the accuracy of the TG’s motion detection is sufficient for use in exergames and to quantify progress in patients’ performance. Considering the findings of this study, the presented exer-game approach has potential as a low-cost, easily accessible support for patients in their home exercise program.

Oxide Bioceramic Composites in Orthopedics and Dentistry

Ceramic composites based on alumina and zirconia have found a wide field of application in the present century in orthopedic joint replacements, and their use in dentistry is spreading. The development of this class of bioceramic composites was started in the 1980s, but the first clinical applications of the total hip replacement joint were introduced in the market only in the early 2000s. Since then, several composite systems were introduced in joint replacements. These materials are classified as Zirconia-Toughened Alumina if alumina is the main component or as Alumina-Toughened Zirconia when zirconia is the main component. In addition, some of them may contain a third phase based on strontium exa-aluminate. The flexibility in device design due to the excellent mechanical behavior of this class of bioceramics results in a number of innovative devices for joint replacements in the hip, the knee, and the shoulder, as well in dental implants. This paper gives an overview of the different materials available and on orthopedic and dental devices made out of oxide bioceramic composites today on the market or under development.