From Mechanobiology to Mechanical Repair Strategies: A Bibliometric Analysis of Biomechanical Studies of Intervertebral Discs

Abstract

Neck pain and low back pain are major challenges in public health, and intervertebral disc (IVD) biomechanics is an important multidisciplinary field. To date, no bibliometric literature review of the relevant literature has been performed, so we explored the emerging trends, landmark studies, and major contributors to IVD biomechanics research. We searched the Web of Science core collection (1900-2022) using keywords mainly composed of "biomechanics" and "intervertebral disc" to conduct a bibliometric analysis of original papers and their references, focusing on citations, authors, journals, and countries/regions. A co-citation analysis and clustering of the references were also completed. A total of 3189 records met the inclusion criteria. In the co-citation network, cluster #0, labeled as "annulus fibrosus tissue engineering", and cluster #1, labeled as "micromechanical environment", were the biggest clusters. References by MacLean et al and Holzapfel et al were positioned exactly between them and had high betweenness centrality. There existed a research topic evolution between mechanobiology and mechanical repair strategies of IVDs, and the latter had been identified as an emerging trend in IVD biomechanics. Numerous landmark studies had contributed to several fields, including mechanical testing of normal and pathological IVDs, mechanical evaluation of new repair strategies and development of finite element model. Adams MA was the author most cited by IVD biomechanics papers. Spine, the European Spine Journal, and the Journal of Biomechanics were the three journals where the most original articles and their references have been published. The United States has contributed most to the literature (n = 1277 papers); however, the research output of China is increasing. In conclusion, the present study suggests that IVD repair is an emerging trend in IVD biomechanics.

Keywords: CiteSpace; annulus fibrosus; co-citation; emerging trend.

Figure 1

Flowchart of literature selection in this study.

Figure 2

Trends of paper counts of IVD biomechanics. Each blue bar represents how many papers in IVD biomechanics were published each year. The trend of publications is represented by the red line, where the nodes were calculated by average count of two adjacent years.

Figure 3

Co-citation network of the references and its clustering. Nodes in the network represent references, and their size indicates citation counts contributed by IVD biomechanical studies. A node may have a number of rings with different colors, which means that they were cited in different time slices. Connections represent co-citation relationships.

Figure 4

Citation bursts in the co-citation network. Red rings around the nodes represent the years when citation bursts can be found.

Figure 5

Nodes positioned between clusters #0 and #1. There were five nodes with highest betweenness centrality highlighted by purple rings, where the thickness indicated the strength of betweenness centrality. Specifically, MacLean et al (2005) and Holzapfel et al (2005) were positioned between clusters #1 and 0, which are more likely to provide insights into topics evolution or emerging trends, while the other highlighted nodes were highly connected to other nodes within the same cluster, which may make them less important than the former. (A) Spotlight model of the co-citation network, which highlights nodes with high betweenness centrality. Close-ups of MacLean et al (2005) (B) and Holzapfel et al (2005) (C), which are positioned between clusters #0 and #1.

Figure 6

Top 20 journals with the most citations contributed by papers of IVD biomechanics in each 5-year slice. The fluctuation of top 10 journals with the most citations were presented. The gray straight line showed the ranking change of a certain journal in each 5-year slice. Spine, Eur Spine J, and J Biomech were the journals cited most by papers in IVD biomechanics in each time slice.