A Bibliometric Analysis and Visualisation of Research Trends in Surface Modification of knee Implants

Several metals are used for Knee implants. The bibliometric analysis had been conducted to understand the active authors, organizations, journals, and countries involved in the research domain of “Surface modification of knee implants”. All published articles related to “Surface modification of knee implants” from “Scopus”, were analyzed using the VOS viewer to develop analysis tables and visualization maps. This article had set the objective to consolidate the scientific literature regarding “Surface modification of knee implants”.” and also to find out the trends related to the same. The most active journals in this research domain were Journal of Arthroplasty and Journal of Bone and Joint Surgery. The most active country was the United States of America. The leading organization engaged in research regarding surface modification of knee implants was the Hospital for Special Surgery of the United States of America. The most active authors were Wright T.M. and Jacobs J.J.


Introduction
An engineered medical device to replace a missing or damaged biological structure is known as an implant. Human knee joints are facing numerous problems including wear, damage, and accidents. Total knee replacement surgery can improve quality of life in cases where repair of the knee is impossible. A knee implant is placed in the knee joint in cases of total knee replacement. knee implants are often used subjected to wear and corrosion and ultimately lead to poor performance, pain, and wastage of money. Similarly, various types of surface treatments and surface coatings can be conducted on knee implants to improve their competency to be used as a material for knee-implants. Material engineering and surface engineering can play a significant role in the development of new types of knee implants; and in enhancing the performance of knee implants.
The surface coating can improve the properties of steel knee implants by using Nanocoatings (Shivendra Kumar, Meenakshi, and Ramana, 2019); Sol-gel coating Surface modification of knee implants". This bibliometric analysis will be a useful platform for future researchers by realizing the top researchers, organizations, and countries involved in research regarding surface coating knee implants. This article is arranged into four sections. The first section is the introduction, followed by the discussion of the methodology by which the research was conducted. The third section deals with results and discussion. The fourth section deals with the conclusion. The following research objectives and research questions were framed for conducting bibliometric analysis systematically.

Research Objectives
a) To consolidate the literature regarding surface coating knee implants b) To find out the trends related to research in surface coating knee implants 1.2 Research Questions a) Who are the active researchers working on surface coating knee implants? b) Which are the main organizations and countries working on surface coating knee implants? c) Which are the main journals related to surface coating knee implants?

Research Methodology
Scopus files had been used for this article. For the article selection, the Boolean used was TITLE (Surface knee implant) on 26/02/2021. All the tables in this paper were created by using Microsoft Excel and VOS Viewer. Grammarly was used for spelling and grammar checks. Mendeley was used for article review and citation. This paper had been inspired by bibliometric analysis in its presentation style, analysis, and methodology from the works (Farhat et     In Co-occurrence analysis, we had used all keyword analyses, by keeping the minimum number of occurrences of a keyword as 100. This combination plotted the map of 35 thresholds, in three clusters. The overlay visualization of co-occurrence analysis of keywords has been shown in Figure 4.  Co-authorship analysis of the countries engaged in the research on "Surface modification of knee implants" had been shown in Figure 5. The overlay visualization map of co-authorship analysis plotted in Figure 5, points out the main countries with their strong co-authorship linkages and clusters involved.  Link analysis and citation analysis were used to identify the most active journal in this research domain. We have taken the parameters of the minimum number of documents of a journal as one and the minimum number of citations of a journal as one for the link analysis and citation analysis. Highlights of the most active and relevant journals related to "Surface coating of knee implants" are shown in table 4. Table 4 shows the journal activity of this research domain through parameters of publication volume, citations, and co-authorship linkages. From the above discussion regarding the bibliometric patterns in the research regarding surface modification of knee implants, this research had observed a gradual increase in research interest regarding surface modification of knee implants from the starting of the millennium and the momentum is going on positively. This points out the relevance and potential of this research domain (Refer to Figure 2). The most active authors in this research domain were Wright T.M. and Jacobs J.J with the highest publication, and co-authorship links; and citations respectively (Refer to table 1). The overlay analysis of top countries researching surface modification of knee implantations indicates that the United States of America was the leading country relating to the highest number of publications citations, co-authorship links (Refer to figure 5). The top journals of this research domain were identified as the Journal of Arthroplasty with the highest number of publications and links; and the Journal of Bone and Joint Surgery with the highest citations. From these wide sources of information, researchers can focus on top journals where they can identify the most relevant and highly cited articles regarding surface modification of knee implants.

Conclusion
The knee implant was an interesting research domain and the most active journals related to this research domain were the Journal of Arthroplasty and Journal of Bone and Joint Surgery. The most active country was the United States of America. The leading organization engaged in research regarding knee implants was the Hospital for Special Surgery of the United States of America. The most active authors who had made valuable contributions related to surface modification of knee implants were Wright T.M. and Jacobs J.J. This research domain offers a new avenue for researchers and future research can be on innovations in surface modification of knee implants.