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1.
Cureus ; 16(6): e61613, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38962641

ABSTRACT

Primary joint replacements are performed increasingly often worldwide, driven by an aging population, improvement in surgical techniques, and advancements in implant designs. While more attention has traditionally been focused on weight-bearing joints such as the hip and knee, shoulder replacement surgeries have gained increasing attention in recent years due to the population's demand for a better quality of life. Thus far, a comprehensive bibliometric analysis of shoulder arthroplasty-related publications using the Scopus database has not yet been conducted. This bibliometric analysis aims to fill this gap by reviewing the Scopus database from its inception until 2023 to examine the literature on shoulder arthroplasty. A total of 5300 publications meeting the selection criteria were included in this analysis. The turn of the century marked a significant turning point for the field of shoulder arthroplasty, with an increasing number of publications produced annually. This trend can be attributed to the improvement of implant designs, which have become more consistent and reliable over time. While the majority of articles were authored by researchers and clinicians from the United States of America (USA), publications by French authors had a higher scholarly impact in the field. There is a noticeable gap in research on shoulder arthroplasty in developing countries, possibly due to the prohibitively high cost of implants and the prioritization of other healthcare sectors. This bibliometric analysis, utilizing Scopus data, serves as a guiding light for researchers, clinicians, and policymakers, potentially fostering collaborative projects and guiding the development of future studies to further advance the field of shoulder arthroplasty, particularly in developing countries.

2.
Biomed Tech (Berl) ; 65(5): 567-576, 2020 Oct 25.
Article in English | MEDLINE | ID: mdl-32459189

ABSTRACT

A transfemoral prosthesis is required to assist amputees to perform the activity of daily living (ADL). The passive prosthesis has some drawbacks such as utilization of high metabolic energy. In contrast, the active prosthesis consumes less metabolic energy and offers better performance. However, the recent active prosthesis uses surface electromyography as its sensory system which has weak signals with microvolt-level intensity and requires a lot of computation to extract features. This paper focuses on recognizing different phases of sitting and standing of a transfemoral amputee using in-socket piezoelectric-based sensors. 15 piezoelectric film sensors were embedded in the inner socket wall adjacent to the most active regions of the agonist and antagonist knee extensor and flexor muscles, i. e. region with the highest level of muscle contractions of the quadriceps and hamstring. A male transfemoral amputee wore the instrumented socket and was instructed to perform several sitting and standing phases using an armless chair. Data was collected from the 15 embedded sensors and went through signal conditioning circuits. The overlapping analysis window technique was used to segment the data using different window lengths. Fifteen time-domain and frequency-domain features were extracted and new feature sets were obtained based on the feature performance. Eight of the common pattern recognition multiclass classifiers were evaluated and compared. Regression analysis was used to investigate the impact of the number of features and the window lengths on the classifiers' accuracies, and Analysis of Variance (ANOVA) was used to test significant differences in the classifiers' performances. The classification accuracy was calculated using k-fold cross-validation method, and 20% of the data set was held out for testing the optimal classifier. The results showed that the feature set (FS-5) consisting of the root mean square (RMS) and the number of peaks (NP) achieved the highest classification accuracy in five classifiers. Support vector machine (SVM) with cubic kernel proved to be the optimal classifier, and it achieved a classification accuracy of 98.33 % using the test data set. Obtaining high classification accuracy using only two time-domain features would significantly reduce the processing time of controlling a prosthesis and eliminate substantial delay. The proposed in-socket sensors used to detect sit-to-stand and stand-to-sit movements could be further integrated with an active knee joint actuation system to produce powered assistance during energy-demanding activities such as sit-to-stand and stair climbing. In future, the system could also be used to accurately predict the intended movement based on their residual limb's muscle and mechanical behaviour as detected by the in-socket sensory system.


Subject(s)
Artificial Limbs , Knee Joint/physiology , Activities of Daily Living , Amputees , Electromyography/methods , Humans , Male , Movement/physiology , Sitting Position , Support Vector Machine
3.
Front Neurosci ; 11: 230, 2017.
Article in English | MEDLINE | ID: mdl-28487630

ABSTRACT

The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users) walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints) were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the lower limb between the initial and terminal swing phases. The outcome of this cyclogram adoption approach proposed an insight into the method of determining the causal effect of manipulating a particular joint's mechanical properties toward the joint behavior in an amputee's gait by determining the curve closeness, C, of the modified cyclogram curve to the normal conventional curve, to enable quantitative judgment of the effect of changing a particular parameter in the prosthetic leg gait.

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