2.1 Data sources and search strategies

In this study, we searched the core collection database of the Web of Science (WoS), which is an internationally recognized database for scientific research. To avoid data errors, the searching time and data downloading were completed on the same day, and the WoS database was searched from January 1997 to March 15, 2024, and the search was measured by ‘AB=(Bone Marrow Stromal Cells OR Bone Marrow Stromal Cell OR Bone Marrow Stromal Stem Cells OR Bone Marrow Mesenchymal Stem Cells OR Bone Marrow Mesenchymal Stem Cells) AND AB=(fracture Cell) AND AB=(fracture heal OR Fracture Healings OR Healing, Fracture OR Healings, Fracture)’; for document type, select ‘Article ‘and, excluding reviews, patents, conference abstracts, books, irrelevant literature, non-English literature, etc., see Fig. 1.

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Fig. 1 Flow diagram of the included articles.

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2.2 Bibliometric analysis

VOS viewer 1.6.18, R Studio language package bibliometrics, and CiteSpace 6.2.R6 software were used for data analysis and visualization.VOS viewer software was used for visual analysis mapping of items such as authors, countries, institutions, highly cited literature, etc., CiteSpace software was used for keyword highlighting and cluster analysis, and bibliometrics was used for partial tabulation and mapping of items such as authors, journals, etc.

3.1 Bibliometric analysis

The annual trend in the number of publications was derived from the WOS Core Collection database for annual publication statistics, in which the WOS database was searched for 599 publications, as shown in Fig. 1. The inclusion of the resultant data was plotted as a bar chart using Excel (2019) software to visualize the research history of the subject area. The overall trend of the number of publications in the WOS Core Collection database showed an upward trend, indicating a gradual increase in research and exploration by scholars in the field of BMSCs in fracture healing. Fig. 2 shows that from 1997, the number of publications reached a peak of 61 in 2021, and the 10 years from 2013 to 2023 was the fastest-growing 10-year period in terms of the number of publications.

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Fig. 2 Trends in the number of publications per year on this field.

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The horizontal coordinate in the figure is the year of publication, the vertical coordinate is the number of articles, and the bar chart shows the specific data of the number of articles per year. After 2021, the number of articles declined slightly, but basically, it is in the same state as that of 2020, and the decline in the number of articles may be affected by the global impact of neocoronavirus pneumonia, and since the literature of 2024 is only counted up to March, there will be a cliff drop. The problem of a precipitous drop will occur, but in terms of analyzing the trend, the increase in the number of publications in 2024 will be sustained.

3.2 Analysis of national collaborations

The knowledge map of national/regional collaboration networks in the field of bone marrow MSCs in fracture healing was analyzed by VOSviewer, with a total of 47 countries and regions. By setting the minimum number of articles required to be published as 2, a total of 36 countries constitute the cooperative contribution network, forming 11 clusters, of which the largest cluster is composed of 6 countries, including Belgium, the United Kingdom, Greece, Norway, New Zealand, and Portugal, which indicates that these 6 countries are highly cooperative in the field of BMSCs in fracture healing, and at the same time, they make greater contributions to the research in this field, as shown in Table 1 and Fig. 3.

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Fig. 3 Annual number of publications in different countries.

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China is the largest contributor to this field. 247 published articles in this field, accounting for 35.19 % of the total number of articles; 5836 citations, accounting for 20.92 % of the total number of citations, the number of articles and citations followed by the United States and Germany ranked second and third, respectively, with 166 articles (23.65 %), 53 articles (7.55 %); 9271 citations (33.24 %), citations 3957 (14.18 %). Through the analysis, it can be seen that China has an absolute leading position among several countries in terms of the number of publications, which indicates that our researchers pay great attention to this field, but from the analysis of the number of citations and the average number of citations per article, we have a certain gap in the number of citations relative to the United States and Germany, and we should enhance the international cooperation to increase China's influence, see Figs. 4 and 3.

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Fig. 4 Collaboration between countries or regions based on VOSviewer.

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3.3 Analysis of author collaboration

The knowledge graph of the author/co-author collaboration network in the field of BMSCs for fracture healing was analyzed by VOSviewer, which resulted in 3745 authors contributing accordingly to BMSCs for fracture healing. Authors with ≥4 publications were analyzed for author co-authorship using VOSviewer (Fig. 5), and as shown in Table 2, the Chinese researcher by Professor Gang Li of the Chinese University of Hong Kong was the first in terms of the number of publications, with 12 publications and an average of 39.75 citations per publication.

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Fig. 5 Collaboration between authors based on VOSviewer.

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Among the top 10 authors in terms of the number of publications, 8 (80 %) authors are from China, and the remaining 2 are from Japan, indicating that Asia has a leading role in the number of publications in this field. Through Table 3, it can be seen that the top 10 authors with the most citations are mostly from the United States and Germany, and China only accounts for 1 (10 %); the number of citations indicates that the articles published by this author in the field have a certain reference value, so China should increase the volume of publications while increasing the authority of the articles.

A total of 18 clusters were formed in Fig. 5 by VOSviewer analysis, and the largest cluster had 11 authors. Chinese researchers were composed of Professor Gang Li from The Chinese University of Hong Kong and Professor Zhijun Pan from the Second Affiliated Hospital of Zhejiang University, which formed the second and third largest clusters, indicating that their cooperation in the field of BMSCs for bone fracture healing had begun to take shape. However, the analysis showed that the researchers' previous collaborations were mostly at the provincial level. However, the analysis shows that the researchers' previous collaborations were mostly at the provincial level, and Chinese scholars should increase their international collaborations to increase China's influence.

3.4 Analysis of institutional collaboration

The number of publications and the number of citations is an important way to show the scientific research ability of a research institution. The literature that has been published in the WOS database is analyzed by VOSviewer, and the lowest number of publications is set to 4. There are 71 institutions, constituting 20 clusters; the largest cluster is mainly composed of Chinese researchers, which is mainly composed of 7 institutions such as General Hospital of the PLA of the People's Liberation Army, Peking University, the Fourth Military Medical University, Third Military Medical University, Jilin University, Lanzhou University, and Harvard University, indicating that China has certain leading characteristics in this field.

The largest cluster was mainly composed of Chinese researchers, mainly from the General Hospital of the People's Liberation Army, Beijing University, the Fourth Military Medical University, the Third Military Medical University, Jilin University, Lanzhou University, Harvard University, and other 7 institutions, which indicates that China has already had a certain leadership characteristic in this field, and also has certain achievements in international cooperation with continuous academic exchanges and cooperation, see Fig. 6.

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Fig. 6 Collaboration between institution based on VOSviewer.

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Analyzed from the perspective of the number of publications, among the top 10 institutions in terms of the number of publications, Chinese institutions occupy seven of them, of which the top three in terms of the number of publications are three institutions in China, mainly Zhejiang University (20 publications), The Chinese University of Hong Kong (18 publications), and Shanghai Jiao Tong University (14 publications), Table 4 illustrates the great contribution made by China in the field of BMSCs for fracture healing worldwide, and the greater scientific investment made by Chinese scholars in this area. And the large investment of Chinese scholars in scientific research in this area (see Table 5).

3.5 Analysis of journal collaboration

The field of BMSCs for fracture healing was analyzed using VOSviewer, and the number of publications was set to 1. A total of 258 journals met the requirements. The top 3 journals with the most publications in this field have 18 or more articles, and the number of citations is over 500, and the top 10 journals in terms of the number of publications are shown in Table 4. The top journal in terms of the number of publications are Journal of Orthopaedic Research and Bone; with 19 publications (3.17 % of the total number of publications). As the largest number of journals in the field of BMSCs for fracture healing, the journal is a medical journal focusing on basic and clinical orthopedic medical research. The journal publishes original research, reviews, and clinical observations on a wide range of orthopedic-related topics and is one of the leading publications in the field of orthopedics. Ranking 3/4/5 are ‘Stem Cell Research & therapy’, ‘Journal of Bone and Mineral Research’, and ‘stem cells’, although these three journals do not publish as many articles as the top 2 journals, analyzed in terms of the average number of citations per article, which is 32.33, 86.20 respectively, 109.92.

Especially ‘stem cells’ is the journal with the highest average number of citations per article in this field, its SCR index is 5.2, and its JCR partition is Q1, which indicates that the articles published by this journal are generally recognized in the field, with a high credibility value, and it even has a certain guidance for the direction of the research in the field of BMSCs for fracture healing. As can be seen in Fig. 7, the first of the top 10 journals that first published an article in the field was the Journal of Bone and Mineral Research in 2003, and the Journal of Orthopedic Research, although it published an article later than the Journal of bone and mineral research, it has been the absolute leader in terms of the number of articles published since 2005; the analysis of Fig. 8 shows that different journals form different clusters according to the publication of articles. The larger the circle in the figure, the larger the number of articles published, and the thicker the connecting lines of different journals, the stronger their cooperation (see Fig. 9).

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Fig. 7 Top 10 journals in terms of annual number of publications.

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Fig. 8 Journal citation collaboration network mapping.

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Fig. 9 Three-Field Plot in this field.

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The relationship between authors, journals, and countries can be known through a Three-Field Plot, the height of the rectangular nodes is proportional to the countries and journals, with the left side representing the journals, the middle representing the countries, and the right side representing the authors, and the higher the height indicates that the research object accounts for a higher proportion of the field and the greater the importance of the field. Through Three-Field Plot analysis, it can be seen that the top 10 international journals are mainly from the United States as well as most of the contributing authors of the journals are from China, which indicates that China attaches importance to the field as well as its leading position in the field, but in general, the amount of contribution of Chinese local journals need to be further increased and increase the influence of the related fields.

3.6 Keyword analysis

3.6.1

3.6.1 Keyword co-occurrence analysis

Keyword analysis can show the research hotspots in the relevant research area, which can enable researchers to have a comprehensive understanding of the next research direction, this study analyzed the keywords in the field of BMSCs for fracture healing through VOSviewer, there were a total of 2639 keywords, and by setting the minimum threshold to 10, there were a total of 108 keywords incorporated, as shown in Table 6 and Fig. 10, and merging the repetitive After the keywords, the highest frequency of occurrence were, respectively, mesenchymal stem cells, differentiation, expression, osteogenic differentiation, fracture healing, repair, and regeneration, osteogenesis in-vitro, angiogenesis, and proliferation, as analyzed in Fig. 11, it can be seen that mesenchymal stem-cells, differentiation, and morrow accounted for one-fifth of all the keywords, indicating that these keywords are the core of this research area.

Table 6 Top 10 keywords in the WOS core ensemble database.

No.	keywords	Frequency	citations
1	mesenchymal stem-cells	215	2000
2	differentiation	143	1243
3	expression	122	1142
4	osteogenic differentiation	107	959
5	fracture healing	96	942
6	repair	94	841
7	regeneration	93	871
8	osteogenesis	91	880
9	in-vitro	72	705
10	angiogenesis	60	571
10	proliferation	57	533

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Fig. 10 Keyword Frequency map.

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Fig. 11 Keyword Frequency map.

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The larger circle indicates the higher frequency of the keyword in this literature, and different connecting lines indicate the connection strength between different keywords, and the thicker connecting lines indicate the stronger connection strength.

3.6.2

3.6.2 Keyword clustering analysis

Keyword clustering analysis is to cluster the main research hotspots in the study area, this study clusters the keywords through CiteSpace software, and the clustering categories are divided into # 0–10 for display, see Fig. 12, and the results show that # 0 (local transplantation), # 1 (bone stem cell), # 2 (bone tissue regeneration), # 3 (integrin-deficient mice), # 4 (fracture heating), # 5 (low-intensity pulsed ultrasound), # 6 (hemopoietic stem cell), # 7 (tumor necrosis factor-alpha), # 8 (musculoskeletal repair), # 9 (bone marrow aspirate), # 10 (bone formation condition).

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Fig. 12 Keyword clustering map of the field.

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3.6.3

3.6.3 Keyword emergence analysis

Keyword emergence is through the analysis of keywords within a certain period, which can reflect the research hotspot and research direction of the period, through the keyword co-linear analysis, can help scholars quickly know the next research trend and focus, this study through the CiteSpace software for keyword emergence analysis, the authors selected 1997 to 2024 keywords in this field to analyze, Fig. 13 shows that these 10 years can be divided into 3 time periods, the first period (2002–2013), the emergence of this period mainly consists of proteitor cell, periosteum, endothelial cell, human bone marrow, stromal cell, etc., the hotspots in this period are mainly for bone marrow interstitial cell, and the research of this period is mainly for bone marrow interstitial cell.

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Fig. 13 Map of keyword bursts in the field.

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The hotspots in this period are mainly for the function of BMSCs and the initial exploration in the field of fracture healing. The second period is (2014–2019), the emergence of this period is mainly based on the first phase of research, the main keywords are transplantation, osteoblast, regeneration, stem cell, osteogenic differentiation, and bone healing, of which osteogenic differentiation is the keyword with the highest frequency and the greatest intensity of emergence in the past 20 years, indicating that osteogenic differentiation plays a huge role in fracture healing, that is, the key to promote bone healing, and an important direction for BMSCs to carry out regulation.

The period of 2014–2019 is a period of rapid increase in publications in this field, and a large number of studies were reported, on the main aspects of bone marrow MSCs for bone regeneration, bone repair, and fracture healing, including the regulatory role of bone marrow MSCs for osteoblasts and osteoclasts, to increase fracture healing, especially for osteoblasts, especially the description of the osteoclasts, is particularly important.

The second period is (2019–2024), the emergence of this period is mainly based on the first and second phases of the research, the main keywords are angiogenesis, growth, activation, proliferation, scaffold, and cell, the publications in these years are relative to the second phase is slightly reduced, It indicates a slight decrease in research fervor, but there are still many researchers who keep exploring, for example, angiogenesis has been the focus of research between 2019 and 2024, suggesting that aspects of angiogenesis in fracture healing are of great importance and that BMSCs can promote fracture healing by modulating angiogenesis, Fig. 14 Scaffold and bone marrow MSC-derived extracellular vesicles are hotspots in recent years. Scaffold provides a three-dimensional culture space for the culture of bone marrow MSCs, which is more conducive to the full play of the stem cell function, while bone marrow MSC-derived extracellular vesicles are an important aspect of their function.

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Fig. 14 Map of keyword bursts in the field.

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4.1 General information

Firstly, by analyzing the trend of publication issuance, the first period: from 1997 to 2006, the period was mainly a preliminary exploration in the field of BMSCs for fracture healing, the number of publications was relatively low, and the number of publications per year had a certain degree of volatility. In the second break: 2007–2013, there were two publication peaks, respectively in 2009 and 2013, also during this period, the number of publications gradually increased every year, and the third phase: 2013–2022, the period was the largest number of publications, indicating that a large number of high-quality papers were published during this period based on the previous development, but in 2022 The impact of the global respiratory epidemic,¹⁵ so in 2022 the literature appeared to fall off a cliff, but from 2023 to 2024, the number of articles is increasing again, and the trend of articles continues to grow.

The analysis was performed through national literature releases, and China was the country with the highest number of publications, while 8 (80 %) of the top 10 authors in terms of publications were from China, and among the top 10 authors in terms of citations in terms of publications, only 1 (10 %) was from China, and the number of citations may suggest the quality of an article. Although China already has some cooperation with other countries such as the United States, the overall intensity is low. The analysis of the trend of the number of articles posted indicates that BMSCs for fracture healing is a topic with research significance, and it is worth investing more energy and money in research. However, the country should strengthen academic communication and increase academic cooperation before the state, and the cooperation between the state and communication should be closer and closer to promote the good development of the field. Previously published papers are mainly basic research, the translation of BMSCs to promote fracture to the clinical work is still a focus of research, but also global researchers need to pay important attention to the direction.¹⁶

4.2 Analysis of research hotspots in the field of bone marrow mesenchymal stem cells for fracture healing

Through the clustering and highlighting analysis of keywords, it is possible to research the BMSCs for fracture healing hotspots in the field of BMSCs for fracture healing. Firstly, through Fig. 12, the first category of keyword clustering includes local transplantation, osteoblast differentiation, osteoblastic cell, etc. This category of clustered terms mainly introduces the corresponding local transplantation at the fracture site, which can increase osteoblast differentiation and promote fracture healing. The ability of BMSCs to require characteristic attention includes the ability of BMSCs to survive after local transplantation, the ability of proliferation, and the potential of osteoblastic differentiation¹⁷; how to enhance the ability of BMSCs in these three directions after transplantation has been a research Various research approaches have been proposed to increase the viability of BMSCs after local transplantation, such as through Mitochondria transfer,¹⁷ TNF-ɑ¹⁸; cytokines like TGF-β1¹⁹; Rapamycin²⁰ and other ways to enhance the viability of MSCs.And many other ways to enhance the viability and proliferation of MSCs, promote osteogenesis, and improve the fracture healing rate. However how to achieve the best intervention effect, how to optimal concentration, and reduce the incidence of postoperative adverse reactions are also important directions.

The second category of keyword clustering includes Bone stem cell, regional gene therapy, cell-mediated gene delivery, bmp2 gene-activating bioceramic, and osteoporotic fracture. A bone stem cell is the theme of this study, but the proliferative effect of MSCs through gene modification is also the focus of research,²¹ He²² and other injectable and porous nano-calcium sulfate/alginate combined with BMP2 gene-modified MSCs and endothelial progenitor cells can significantly enhance the vascularised bone regeneration, but there are limitation and safety issues of gene modification technology for MSCs, especially in the late stage. Herberg et al. overexpressed SDF-1β in BMSCs by cell-mediated gene delivery, and together with bone morphogenetic protein-2 (BMP-2), they promoted osteogenic differentiation of bone marrow-derived mesenchymal stem/stromal cells (BMSCs) to facilitate fracture healing. BMP is involved in various stages of bone metabolism, and BMP-2 is one of the important bone-forming factors, inducing the differentiation of endo- and periosteal bone and bone marrow stromal cells into osteoblasts, enhancing the role of the regenerative capacity of the bone bed, and activating or inducing perivascular mesenchymal stromal cells to differentiate into chondrocytes and osteoblasts.^23,24

Liu²⁵ et al. established animal and cellular experiments and found that Recombinant human BMP-2 could promote the differentiation of BMSCs through the CDC42/PAK1/LIMK1 pathway, which provided a new idea for later studies. Fractures are often accompanied by osteoporosis,²⁶ and the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has proposed two of several markers as reference analytes for predicting fracture risk; serum type I procollagen N pro-peptide (s-PINP) and serum type I collagen C-terminal cross-linking telopeptide (s-CTX) were used as markers of bone formation and bone resorption, respectively, and studies have shown showed s-PINP significant correlation with fracture risk²⁷ Zhu²⁸ found that in an animal model of osteoporotic fracture, Tensile strain promotes the differentiation of BMSCs to osteoblasts, and the differentiation of BMSCs promotes the expression of lncRNA-MEG3, and lncRNA-MEG3 increases the differentiation of BMSCs in a positive feedback at the same time and this positive feedback promotes fracture healing. This study provides good preventive measures for elderly patients, especially postmenopausal female patients, and provides new ideas for the prevention and diagnosis of osteoporotic fractures.

The third category of keyword clustering includes integrin-deficient mice, expressing insulin-like growth factor-i, and jagged1 expression. Integrins mediate cell adhesion to extracellular matrix components²⁹ GUO³⁰ and others showed that integrin-targeted (DOPA)4-S5-GRGDS derived from purple mussel foot protein could be easily coated on the surface of titanium plates, which could effectively inhibit RANKL-induced osteoclast over-activation, and reduce interfacial osteoclastogenesis at both gene and protein levels. The inhibitory effect of the peptide coating may be related to the targeting of integrins to the RGD sequence, which interferes with the integrin ɑvβ3, affecting the cytoskeletal organization and function of osteoclasts and thus inhibiting osteoclast overactivation and the generation of osteoclasts at the interface. It has been suggested that insulin-like growth factor (IGF) plays an important role in the process of bone production and healing.IGF consists of 2 growth factors, 2 classes of receptors, and a variety of proteins.IGF-I and IGF-II are important mediators in the process of bone healing,³¹ and IGF-I is expressed in osteoblasts, which promotes bone mineralization and maintains bone mass.Myers³² found that IGF-I combined with BMSCs transplantation in concurrently treated mice with fractures showed increased bone marker formation in the former compared to those without combined IGF-I, also confirming its effectiveness in bone repair. jagged1 (Jag1) is a notch ligand, and activation of notch signaling by the intracellular structural domains of jagged1 or notch2 inhibits glucose metabolism and osteoblast differentiation³³; playing a key role in vascular hemostasis and remodeling, Jag1 negatively regulates the marrow osteochondral progenitor pool, Jag1 is required for normal trabecular bone formation.³⁴

The fourth category of keyword clustering includes fracture heating, alginate culture, biological scaffold, human periosteum, orthopedic tissue engineering, chondrogenic differentiation, actin cytoskeleton, and antioxidant defense.

Alginate is often used in the fabrication of hydrogels and alginate has good biocompatible properties, as well as low degradation rate and good cross-linking properties.³⁵ Loading Platelet plasma and BPM2 with Alginate, can not only promote the stable differentiation of BMSCs but also promote fracture healing because Alginate hydrogel can diffuse macromolecules quickly and better perform the properties of BMSCs, which is known as a good carrier for delivering MSCs and other bioactive substances.^36,37 In orthopedic tissue engineering, modified biological scaffolds and the addition of exogenous growth factors can better promote the differentiation of BMSCs; a strong vascular supply to maintain sufficient oxygen and nutrients, and the removal of toxic wastes from the tissues can stabilize BMSCs for differentiation.³⁸ Black³⁹ showed that by bovine extracellular matrix hydrogel and a novel biocompatible melt electro-written medical-grade polycaprolactone scaffold, in Stro-4 + BMSCs have shown potential to aid bone repair in vitro and in small in vivo models of bone defects using specific scaffolds. Periosteum has an important role in promoting osteogenesis. Mesenchymal stem cells (MSCs) are mainly derived from bone marrow and periosteum, and periosteum plays an important role in fracture repair and bone regeneration, and cells derived from skeletal muscle can play an important role in opening when the periosteum is damaged. The fracture repair process occupies the fracture-healing tissue.^40,41

Angiogenesis plays an important role in bone regeneration. G-protein-coupled receptor (GPCR) kinase 2-interacting protein-1 (GIT1) is an important protein involved in fracture healing by regulating angiogenesis.GIT1 knockout mice exhibit impaired angiogenesis and delayed fracture healing, and GIT1 promotes paracrine secretion of BMSCs by regulating Notch/NF-κB signaling, which enhances the positive effects of angiogenesis and fracture healing.⁴²MSCs are precursor cells for osteoblasts, chondrocytes, and adipocytes, as well as for other cell types; it has been pointed out that MSCs are mainly involved in the biological properties by secretion from extracellular vesicles (EVs), such as inflammation, angiogenesis, cell differentiation, and migration.^43,44

The bone regeneration cycle begins with the activation of osteoblasts and preosteoblasts in the bone marrow, which secrete receptor activators of NF-κ B ligand (RANKL) on the bone surface. This protein is a member of tumor necrosis factor (TNF) and interacts with receptors present on osteoclast precursors called NF-κB receptor activators (RANK).^45,46 Osteoblasts, as well as other cells of the bone marrow, produce osteoprotegerin (OPG), which inhibits the eventual differentiation and activation of osteoclasts, and vascular endothelial growth factor (VEGF), which has been implicated as an osteogenic-angiogenic coupling factor.⁴⁷ After the fracture occurs, the inflammatory response is stimulated and activated, the level of inflammatory cells increases, and the increase in inflammatory factors becomes maximal on the day, after the acute phase, it gradually decreases for about 1 week, and the inflammatory response may delay the bone healing, and the content of EV is determined by the state of its stem cells, it was pointed out that the BMSCs-EV in combination with polycaprolactone scaffolds is more favorable to bone regeneration, by promoting the induction of osteoblast differentiation and the inhibition of the inflammatory genes to achieve this.^48,49

4.3 Strength and limitation

In the broad field of orthopedic diseases, fracture undoubtedly occupies a significant position, and its research value is far-reaching and its clinical application is promising. Especially in the pursuit of accelerated fracture healing, regenerative medicine technology has become the focus of our attention. Compared with traditional literature review methods, CiteSpace analysis provides us with a new perspective, which can reveal research priorities and trends more precisely. However, this tool is not a panacea. Its limitation is that it is not a complete substitute for the exhaustiveness and comprehensiveness of a systematic search. Firstly, we need to be wary of possible inconsistencies in the collection of literature data, which may undermine the credibility of our research.

Secondly, discrepancies in data updating may also lead to discrepancies between the search results and the actual number of literature included. When using CiteSpace for literature analysis, it was also not difficult to find that the software had some bias in assessing author influence. Specifically, academics with a single first-author publication tended to receive lower rankings than those with only a handful of publications as an intermediate author. However, in academia, first authorship often implies higher contributions and greater impact. Therefore, this ranking method may not be entirely accurate.

Nonetheless, CiteSpace-based literature visualization and analysis still provide us with a valuable tool that helps us gain a deeper understanding of the authoritative literature in our research area and lays a solid foundation for subsequent research. We tried this approach for the first time in our comprehensive econometric analysis of the literature in the field of BMSCs and fracture healing. By analyzing authors, countries, institutions, highly cited literature, keyword co-occurrences, clustering, and outbursts, we revealed cutting-edge and hot directions in the field. However, this study also has its limitations. First, our analyses are primarily based on the WoSCC database, a choice that, while based on its importance in the field of bibliometrics, may have led us to overlook literature from other important sources. In addition, due to the continuous updating of the database, some of the most recent, high-quality literature from this year was not included in our study. Finally, a limitation of bibliometrics is its inability to fully assess the level of individual studies, as the number of citations for new articles may be relatively small due to their recent publication date. All these limitations need to be noted and overcome in our future research.