Fig. 8
From: Bibliometric and LDA analysis of extracellular vesicles in osteoarthritis
Topic Dynamics and Document–Topic Structure: a Temporal trends of latent topics in extracellular vesicle research on osteoarthritis (2003–2024). Annual mean posterior proportions are shown for 15 topics (Topic 1–Topic 15), with per-year observations (dots) and fitted linear trends. The slope direction and magnitude summarize rising versus declining thematic attention over time. b Husson–Jongmans biplot of the document–topic distribution. Principal component analysis of the topic posterior matrix (θ). PC1 and PC2 explain 10.3% and 8.6% of the variance, respectively. Gray points represent individual documents; colored arrows represent topic vectors (arrow length indicates contribution to the component; direction indicates association with the axes). Topics form four clusters (cluster 1–4; colors as in legend), highlighting thematic grouping and document–topic relationships
