Progress and research trends in neurogenic bladder after spinal cord injury bibliometric analysis based on web of science database: An observational study.

1. Introduction

Neurogenic bladder (NB) dysfunction commonly complicates spinal cord injury (SCI), with management objectives encompassing social continence, low-pressure storage, and complication prevention. [ 1 ] A prior study identified renal failure as the primary cause of death following SCI. [ 2 ]

Although neurorehabilitation has shown potential in enhancing locomotion in paralyzed rats, its effect on bladder function remains uncertain. [ 3 , 4 ] Wu and colleagues [ 5 ] discusses the significance of bladder care and advocates for the use of sterile intermittent self-catheterization procedures to mitigate urinary-tract infections in SCI patients. SCI is characterized by high morbidity, disability, mortality, and a low cure rate. Among these complications, NB stands out as one of the most severe, affecting approximately 65.96% of cases. [ 6 , 7 ] NB primarily manifests as urinary retention and urinary incontinence, with symptoms often alleviated through indwelling or intermittent catheterization. However, these procedures can predispose individuals to urinary tract infections, and in severe instances, may culminate in renal failure, posing a significant risk to life. [ 8 ]

Bibliometrics is a field of study focused on analyzing the quantity, quality, citations, and impact of scientific literature. Utilizing methods from statistics, computer science, and informatics, it uncovers trends in scientific research, interdisciplinarity, and the influence of academic work by analyzing data such as publication counts, citations, and author collaborations. Bibliometric research encompasses scientific journals, academic papers, monographs, and other literary forms. [ 9 – 11 ]

The VOSviewer software was developed by a team from the Centre for Science and Technology Studies (CWTS) at the University of Leiden, The Netherlands. CWTS specializes in scientometrics and scientific evaluation research, employing econometric methods to evaluate the impact, collaborations, and trends in scientific research. [ 12 ] The Citespace software was developed by a team from the Department of Informatics at the University of Pittsburgh, USA, led by key member Chaomei Chen, Professor of Informatics, among others. Citespace is primarily designed for visualizing and analyzing scientific literature data, focusing on exploring citation relationships and identifying hotspots and trends in the research field. [ 13 ] Previous studies have shown a scarcity of bibliometric research focusing on NB after SCI, particularly within the last 5 years. Thus, this study analyzes publications on NB after SCI from 2000 to 2024 using state-of-the-art bibliometric methods. Revealing the current research landscape and identifying hotspots in this area can offer scholars valuable insights and perspectives.

2. Materials and methods

2.1. Data sources and search strategies

In this study, we conducted a search using the core collection database of Web of Science (WoS), a globally recognized scientific research database. To ensure data accuracy, the search and data download were completed on the same day. The search spanned from January 1, 2000 to March 27, 2024, using the following search criteria: “TS = (‘spinal cord injur*’ OR ‘spinal injur*’ OR ‘spinal cord traum*’ OR ‘spinal traum*’ OR ‘paraplegia’ OR ‘quadriplegia’ OR ‘tetraplegia’) AND TS = (‘neurogenic bladder’).” We specifically selected articles while excluding reviews, patents, conference abstracts, books, irrelevant literature, and non-English literature. Refer to Figure 1 for details.

2.2. Bibliometric analysis

Relevant publications that met the inclusion criteria were retrieved from the Core Collection database in WoS and were exported as a plain text file with “Full Record and Citations” and named “Download_xxx.txt.” The exported documents were then imported into VOSviewer 1.6.19, CiteSpace 6.2.R2 software, the R Studio language package bibliometrix, and Scimago Graphica 1.0.24 software to construct visualization maps and perform statistical analysis.

The parameters of the CiteSpace software were set as follows: the time span was set from January 2000 to March 2024; the number of years per slice was set to 1; node types included keywords, categories; the selection criteria were set to the first 25 per slice; pruning selected pathfinders, pruned sliced networks, and pruned merged networks, and the other settings were kept at the default software settings. For VOSviewer software, visual analysis mapping of items such as authors, countries, institutions, and highly cited literature. The minimum thresholds for the number of publications for countries/regions, institutions and authors were set to 5, 9, and 7, respectively. The minimum threshold for the number of citations was set to 5. Scimago Graphica was used to plot the visual analysis of national collaborations. bibliometrix was used for the author-journal-country collaborative network 3-field plot, keyword year of issue volume trend topics, etc, and the table was mainly drawn using Excel.

3. Results

3.1. Bibliometric analysis

According to our search criteria, a total of 1095 publications were included in this study, comprising 913 research articles and 182 reviews. Publication trends related to NB after SCI are illustrated in Figure 2 . The analysis revealed a consistent increase in publications from 2000 to 2024. The peak occurred in 2022 with 101 publications, marking the fastest 10-year period from 2012 to 2022. Despite the global impact of the COVID-19 pandemic from 2020 to 2022, the field maintained its upward trajectory, reaching 99 publications in 2022.

This indicates a sustained interest and effort in researching NB after SCI, underscoring its clinical significance and the necessity for staying abreast of advancements. Moreover, the rising trend reflects growing interest in exploring preventive and therapeutic strategies for the physiological and pathological mechanisms of this condition, drawing attention from an increasing number of scholars.

3.2. Analysis of country cooperation

Analysis of 1095 publications revealed contributions from 61 countries worldwide to the study of NB after SCI. Table 1 provides data on the top 10 countries ranked by publication count, citation count, average citations per article, and H-index. The United States, with 440 articles (41.24%) and 11,416 citations (47.32%), demonstrates its significant contribution and leading position in the field. China ranks second, with 163 articles (15.28%) and 1370 citations (5.68%). Despite a gap compared to the United States, China, publication count surpasses that of other countries.

While Figure 3 illustrates China substantial contribution to the field, it is essential to note its lower national recognition compared to the U.S., as indicated by citations and the H-index. China should enhance its presence by fostering international collaborations and enhancing publication quality. Among the top 10 countries by publication count, North America (2, 51.36%), Europe (5, 25.96%), and Asia (3, 22.68%) stand out. Interestingly, despite Europe having 5 countries and Asia having 3, their total publications are fewer than those of the 2 North American countries combined.

Figure 4 analysis reveals that node size represents the volume of contributions, while line thickness indicates the frequency of collaborations. The largest clusters comprise countries led by the United States and China, highlighting their close collaboration and frequent interactions. This underscores the strengthening international cooperation between these nations, fostering advancements in the field.

3.3. Analysis of author collaboration

Analysis of 1095 publications revealed the involvement of 4530 authors in this field, each contributing to a single publication. Table 2 indicates that 6 out of the top 10 authors (60%) by publication count were from the United States, Topping the list is welk, blayne from Western University in Canada, and in second place is Myers, Professor Jeremy B from University of Utah.

Figure 4 illustrates that Professor Jeremy Myers published his inaugural research in the field in 2016. Subsequently, he contributed 2 to 5 articles annually, peaking at 6 publications in 2019. Within the top 10 authors by publication volume, only 1 is from China. This indicates that despite China large publication output, research efforts are relatively fragmented and lack collaboration, suggesting a need for better organization.

Among the top 10 authors, Prof Blayne Welk from Western University in Canada stands out with 39 publications and 588 citations, placing him among the top 2 authors in terms of both publication count and citations. Prof Blayne Welk made his initial publication in the field in 2012. Despite commencing his research later than other authors, he has consistently contributed to the field every year from 2012 to 2024, demonstrating prolific publication output alongside high-quality research.

Figure 5 illustrates that research activities in the field began around 2000, peaking in 2019. Among the top 10 authors by publication count, 5 authors published ≥ 6 articles in 2019, indicating a surge in research output during that year, highlighting the significant research potential and collective scholarly effort in the field. Analyzed using VOSviewer in Figure 6 , with a minimum of 6 publications, 59 authors formed 26 clusters.

The 2 largest clusters, comprising 9 and 8 authors, respectively, feature collaborative teams led by Prof Juergen Pannek from Switzerland and Prof Juergen Pannek from Canada. This indicates close collaboration within these teams transcending national boundaries, fostering the advancement of the field. Conversely, despite the United States’ higher publication count, collaboration efforts need further strengthening.

3.4. Institutions analysis

Analysis of 1095 publications revealed the involvement of 4530 authors in this field, with each author contributing to one publication. Table 3 reveals that among the top 10 institutions by publication count, 7 (63.63%) are from the United States.

The leading institution is the University of Michigan, with 47 publications, cited 1360 times, and averaging 28.94 citations per article. The 2nd-ranked institution is the University of Pittsburgh in the United States, with 37 publications, cited 1011 times, and averaging 27.32 citations per article. The 3rd-ranked institution is Western University in the United States, with 33 publications, cited 447 times, and averaging 13.55 citations per article. Notably, all top 3 institutions are from North America, suggesting a high level of concern for this disease in the region. Additionally, the relatively developed economy of this region may be related to the attention given to this type of disease. Furthermore, the University of California, Irvine stands out in terms of citations, with only 6 publications but an impressive 1580 citations, averaging 263.33 citations per article. The average citation count serves as an indicator of research influence and quality. Generally, a higher average citation count signifies broader recognition and appreciation within the academic community. Thus, a higher average citation count suggests widespread recognition and value of the research conducted in the field or by the scholar. The research conducted at the University of California, Irvine primarily focuses on rat models to simulate SCI and employs noninvasive ultrasonographic methods to identify spinal cord injuries. Additionally, they explore bladder function in rat models through spinal stimulation of the upper lumbar spinal cord following intervention. [ 14 , 15 ]

Analysis of Figure 7 revealed larger node circles representing institutions such as the University of Michigan, the University of Pittsburgh, and Western University. While there is some cooperation between different institutions, overall, the collaboration appears scattered. Researchers should enhance cooperation between institutions to foster further development in this field.

3.5. Journal collaboration analysis

Journal collaboration analysis involves studying and analyzing the collaborative relationships among different journals within a research field. By illuminating the cooperation network, this analysis unveils relationships between journals, aiding researchers in comprehending the overall structure of collaboration within the field and identifying potential collaboration opportunities. Facilitating academic exchange and cooperation, journal collaboration analysis offers a reference point for fostering collaboration between journals. Researchers can identify suitable partners and promote academic exchange and cooperation by discerning the collaborative relationships between journals. With a publication count set at 1, a total of 325 journals meet the criteria.

The top 3 journals with the most publications in this field all have 80 or more articles and more than 1200 citations, and the top 10 journals ranked by the number of articles are shown in Table 4 . In terms of the number of articles published, the top journal is Neurourology and urodynamics, with the JCR classification of Q3, and its impact factor of 2.00; it publishes 107 articles (9.77% of the total number of articles published), and its impact factor is 2.00. Its impact factor is 2.00; it has published 107 articles (9.77% of the total number of articles), with 2101 citations and a total link strength of 14,118, indicating that the journal has good contribution and general recognition by scholars in the field, no matter in terms of the number of articles or the number of citations. Whether analyzed in terms of the number of articles published or the number of citations, the journal is ranked first, which also shows the value of the journal in this field. Neurourology and urodynamics covers research results in the fields of neurourology and urodynamics, including but not limited to bladder dysfunction, urinary incontinence, urethral dysfunction, and NB disease. It is widely cited and read and provides an important academic communication platform for researchers in related fields. Among the top 10 journals, those belonging to JCR Q1 are, “journal of urology,” with 42 articles published and 1409 citations, averaging 33.55 citations per article, “bju international,” with 25 articles published and 813 citations, averaging 32.52 citations per article; “European journal”, with 17 articles and 1221 citations, averaging 71.82 citations per article; the average citation per article can be one of the indicators to measure the influence and importance of a journal or a paper. Generally speaking, the higher the average number of citations per article, the greater the influence of the journal or the paper in the academic world, and the higher the possibility of being recognized and cited by peer scholars.

Analysis of Figures 8 and 9 reveals that different journals form distinct clusters based on article publications. Larger circles represent higher article volumes. Figure 8 analysis indicates previous cooperation among journals such as “Neurourology and Urodynamics,” “Journal of Spinal Cord Medicine,” and “Spinal Cord.” Three-Field Plot analysis highlights that the top 10 international journals primarily originate from the United States, with most contributing authors from China. This underscores China significant attention and leadership in the field. However, the contribution of Chinese local journals needs enhancement to elevate the influence of related fields.

3.6. Keywords analysis

Keywords provide a central summary of article content and facilitate analysis of research frontiers in NB outcomes after SCI. Keywords occurring more than 100 times include SCI (778), neurogenic bladder (NB) (648), management (211), quality of life (155), and dysfunction (140). These keywords, listed in Table 5 , demonstrate association strengths exceeding 1000 for the top 5 frequencies. High-frequency keywords reflect scholarly focus and relevance. Notably, “SCI” is widely recognized as a key research area, given its high occurrence frequency.

The main focus of the study is NB, particularly its impact on quality of life and follow-up care. Symptoms such as micturition, incontinence, dysfunction, urinary-tract dysfunction, and detrusor overactivity are of utmost concern to patients and scholars alike. Clean intermittent catheterization is a commonly used clinical intervention for NB, among various available methods.

Through the keyword analysis cluster analysis in Figure 10 , it can be seen that #0 nerve transfer; #1 urinary-tract infection; #2 quality of life; #3 electrical stimulation; #4 botulinum toxin: #5 myelodysplasia; #6 case report, etc. Different clusters indicate different research focus and direction in this field. Through the keyword trend topics in Figure 11 , it can be seen that different time hotspots exist at different time points, and through the results, it can be seen that management, SCI, and NB are the high-frequency words for research in 2017 to 2018, indicating that scholars pay particular attention to this research focus during this period of time.

As can be seen through Figure 12 , during the period of 2000 to 2010, anterior root stimulator, NB dysfunction, and micturition are the keywords with longer frequency and time of issuance. First of all, in these 10 years journals, bladder dysfunction is the primary concern of researchers, and bladder dysfunction is often accompanied by micturition. To address this situation, researchers proposed anterior root stimulator and other methods of intervention. During the period 2010 to 2020, keywords are needed to be mentioned, epidemiology, people, bowel, validity, and such terms are mentioned, and combining with Figure 11 , we find that a large number of keywords and publications were reported in these 10 years, and it is also the golden 10 years for the development of the field, which is studied in detail on various aspects of the field, including its pathogenesis, patient populations, how to ensure the effectiveness of treatments, and other studies. During the period 2020 to 2024, keywords such as clinical practice, international standard, guideline, and life are included, which indicates that on the basis of the development in the past 20 years, a certain scale has already appeared, and there is the problem of nonstandardisation in relation to the large number of studies in the previous period, and how to conduct standardized guidelines to treat patients has been a concern for many researchers. At the same time, in the process of carrying out standardized treatment and guidance for patients, more detailed plans and more comprehensive plans for surgery as well as postoperative care and rehabilitation have also been mentioned a lot.

4. Discussion

This study conducted a comprehensive search of 1018 original research papers and 182 reviews from 2000 to 2024 using the WoS core database focusing on NB after SCI. Analyzing publication trends, the period from 2010 to 2020 exhibited more stable publication rates. However, 2022 witnessed the highest number of publications, indicating a surge in research activity, substantial researcher engagement (Fig. 6 ), and increased attention from journals towards this topic during that year. [ 16 ]

Analysis of recent publications indicates continued prominence and activity in this research area. While exploration in this domain is increasing alongside publication rates, numerous key scientific questions remain unanswered. Despite significant breakthroughs, numerous challenges persist in bladder care and rehabilitation post-SCI, spanning various scientific disciplines. Given the critical importance of these issues, greater investment in human, material, and financial resources is imperative to foster overall development in this field. This entails not only researcher training and guidance but also investment in and support for large-scale clinical cohort studies, improved statistical methodologies, and robust data analysis techniques, among others. Strengthening collaboration between countries, territories, and research institutions is essential in today’s globalized context, facilitating the removal of academic barriers, breaking down information silos, and promoting data and research sharing to expedite scientific progress. Additionally, establishing deeper and broader cooperation enhances knowledge dissemination and exchange, leading to improved scientific problem-solving and enhanced clinical care provision. For instance, collaborative research efforts can yield more effective treatments, ultimately enhancing healthcare service quality and efficiency.

In terms of keyword analysis, by analyzing the keyword analysis clustering analysis, #0 nerve transfer, mainly including reflex pathway; reinnervation, etc, this kind of clustering vocabulary provides a surgical method, that is, a restoration of nerve function through nerve transfer and reinnervation. Lin and Hou [ 17 ] conducted microanastomosis of the proximal portion of the unilateral S1 ventral root (VR) to the distal parts of the S2 and S3 VRs in 9 patients. Results demonstrated that restoring bladder innervation through S1 nerve transfer effectively treats non-tension bladder, offering novel insights into patient care and enhancing bladder function. Another study observed that in a canine model, a novel reflex pathway was established by epidural transfer of the left L5 VR to the left S2 VR root, alongside epidural transfer of the L5 dorsal root (DR) to the S2 DR, coupled with nerve graft utilization. The corresponding nerve on the right side remained intact as a control. Motor-to-motor and sensory-to-sensory epidural nerve transfers in the upper sacral region reconstructed afferent and efferent nerve pathways to the non-tension bladder in dogs. [ 18 ]

Gomez-Amaya et al [ 19 ] succinctly summarized nerve transfer techniques in a systematic review. Main modalities comprise end-to-end repair of sacral nerve roots, transfer of nerve roots from other spinal cord segments to sacral nerve roots, transfer of intercostal nerves to sacral nerve roots, transfer of various somatic nerves to pelvic or anal nerves, direct reinnervation of the urinary muscles, and creation of an artificial reflex pathway between the skin and bladder through the central nervous system, among others. However, each nerve transfer modality possesses its own advantages and disadvantages. Selecting the most suitable approach based on the patient’s individual circumstances and long-term efficacy is a crucial consideration for researchers. Quality of life, encompassing aspects like reliability and validity, is also a primary concern. NB following SCI not only affects the patient’s physical function but also their psychological well-being, exerting negative impacts on their overall quality of life.

Guillotreau et al [ 20 ] identified the adverse effect of NB dysfunction on patients’ quality of life (QoL) and assessed the effect of ileal conduit urinary diversion on their QoL. While this technique alleviates restrictions and limitations associated with urinary diversion and enhances urinary-related QoL in patients with NB dysfunction, it does not affect overall QoL. The primary types include indwelling catheterization (indwelling catheter) and intermittent catheterization (intermittent catheterization). Intermittent catheterization stands as the gold standard in treating NB voiding disorders, notably reducing complications such as urinary tract infections, vesicoureteral reflux, and hydronephrosis. [ 21 ] Urodynamic Studies (UDS) serve to guide clinical decision-making and simplify this complex disease state; based on UDS findings, physicians can tailor treatment plans, encompassing medication, neuromodulation, biofeedback, timed voiding, or surgical intervention. These interventions aim to mitigate UTI and upper urinary-tract injury risks while enhancing voiding control and the patient’s quality of life. [ 22 ]

Questionnaires serve as crucial tools for patients to assess their general condition and reflect their quality of life visually, providing valuable documentation. Yesil et al [ 23 ] evaluated the validity and reliability of the Turkish version of the Intermittent Self-Catheterisation Questionnaire (ISC-Q) in SCI (SCI) patients, confirming its reliability and validity in assessing catheterization-related quality of life. #3 electrical stimulation, including techniques like acupuncture, demonstrates efficacy in treating urinary storage disorders when combined with pelvic floor electrical stimulation and biofeedback, offering effectiveness, ease of use, and safety. Additionally, stimulation using fine needles (percutaneous tibial nerve stimulation) can ameliorate OAB symptoms, significantly improving the average first involuntary urethral muscle contraction and average maximum bladder capacity during the stimulation period. [ 24 ] Electroacupuncture, a treatment modality blending traditional Chinese medicine with modern medical technology, shows promise in managing this type of disease.

Zhang et al [ 25 ] established a rat model of SCI and observed that electroacupuncture (EA) enhances NGF/TrkA and AKT signaling in local nerves of the injured spinal cord, reduces apoptosis of spinal cord cells, thus increasing neuronal activity and accelerating nerve repair. Additionally, EA improves urinary reflex coordination, enhancing NB function post-SCI. However, the efficacy of acupuncture for this patient group remains controversial. Lin et al [ 26 ] conducted a meta-analysis and observed that while some studies suggest EA reduces residual urine volume significantly compared to pharmacotherapy plus intermittent catheterization (ICP), current evidence is insufficient to support acupuncture’s efficacy in treating NB post-SCI, attributed to poor methodological quality and a limited number of trials.

Wu et al [ 27 ] conducted EA treatment on 16 participants, revealing that after 8 weeks, 5 patients (31%) regained normal voiding function, 3 patients (38%) partially regained it, while 5 patients (31%) experienced no change. #4 botulinum toxin: This category of keywords, including detrusor overactivity and overactive bladder, mainly describes drug treatment for this condition. The contraction of the urethral muscle is primarily stimulated by acetylcholine binding to muscarinic receptors. Muscarinic receptor blockers play a crucial role in pharmacological management of overactive bladder by blocking these receptors.

Peyronnet et al [ 28 ] concluded that in cases of failure after initial detrusor injection of abobotulinum toxin, switching to onabotulinum toxin is effective. Further investigations are needed to assess whether replacing onabotulinum toxin with abobotulinum toxin yields similar results. Commonly used drugs include M receptor blockers to inhibit urethral muscle contraction, and β3 receptor agonists to alleviate urinary frequency and urgency. Desmopressin tablets can significantly reduce the volume and frequency of nocturnal urination, greatly improving patients’ quality of life. Midodrine hydrochloride primarily acts on α1 receptors, increasing internal bladder sphincter tension, and showing relative efficacy in treating urinary control during the storage phase of NB. Recent studies suggest that phosphodiesterase inhibitors have a notable effect on detrusor overactivity and may serve as an alternative or adjunct to antimuscarinic therapy in the future. [ 29 – 31 ] #5 myelodysplasia; including spina bifida, myelomeningocele; primarily elaborates on the etiology of spinal cord injuries, where urethral sphincter insufficiency may be a significant contributor to urinary incontinence in NB patients. Puboprostatic sling can effectively treat neurogenic voiding dysfunction resulting from urethral insufficiency. Surgical approaches can be broadly categorized into 2 types: those aimed at increasing bladder contractility, such as selective dorsal rhizotomy [ 32 ] and sacral neuromodulation, [ 33 ] and those aimed at reducing bladder sphincter tone.

Procedures for reducing urethral resistance include Urethral Sphincteric Botulinum Toxin Injection, [ 34 ] external urethral sphincterotomy, [ 35 ] and insertion of urethral stents. [ 36 ] Stem cell therapy for SCI repair has been a research focus. In vitro models using stem cells or neural precursor cells (NPCs) for NB treatment have shown the efficacy of stem cells from various sources in promoting neural regeneration and improving bladder function. Mesenchymal stem cells (MSCs) were also found to inhibit fibrosis via the TGF-beta 1 signaling pathway. [ 37 ]

Adipose tissue-derived mesenchymal stem cells (AT-MSCs) were studied for smooth muscle cell (SMC) differentiation on scaffolds and tissue culture polystyrene (TCPS) surfaces. This biofunctional scaffold aims to repair and regenerate bladder tissues and promote the restoration of NB (NGB) function through the multidirectional differentiation potential of stem cells. [ 38 ] Fan et al [ 39 ] utilized bone marrow stem cell-derived exosomes (BMSC exosomes) along with neural tissue-like conductive hydrogels to modulate microglial cell M2 polarization via the NF-κB pathway. This approach synergistically enhanced neuronal and oligodendrocyte differentiation of neural stem cells (NSCs) while inhibiting astrocyte differentiation. Additionally, it promoted axon outgrowth through the PTEN/PI3K/AKT/mTOR pathway. Ran et al [ 40 ] utilized a biological scaffold consisting of autologous plasma exosomes (AP-EXO) loaded with neurons targeting peptides (RVG) and growth-promoting peptides (ILP and ISP) to effectively promote nerve repair.

Spinal cord injury is also one of the extremely high keywords in the keyword list. Spinal injury refers to damage or destruction of the continuity, integrity and stability of spinal structures, including damage to the vertebrae, intervertebral discs, ligaments that stabilize the spine, and paravertebral muscles. It refers to the damage to the neural structures (including the spinal cord and nerve roots) and their functions in the spinal canal caused by various reasons, and the dysfunction of the spinal cord (motor, sensory, reflexes, etc.) at the level of injury and below. According to the causative factors, there are 2 major categories: traumatic and nontraumatic. [ 41 , 42 ] For acute SCI injuries, timely intervention as well as reasonable and effective postoperative functional exercises are closely related to postoperative quality of life. [ 43 ]

Surgery, as the main method of treating spinal fracture with spinal nerve injury, can reset the spinal anatomy, relieve nerve compression, and increase the stability of the patient’s spine at the same time, and the choice of the timing of the surgery will directly affect the effect of surgical treatment. [ 44 ] As for after SCI, the timing of surgery is controversial. One study noted that early surgical intervention within 24 hours of initial injury was associated with better prognosis and functional outcomes. [ 45 ] And early postoperative intervention is equally strongly associated with a reduction in postoperative complications. A meta-analysis [ 46 ] showed that activity-based intervention like transcranial magnetic stimulation, functional electrical stimulation, and robotic-assisted treadmill training are effective in improving function in individuals with SCI. A large number of excellent bibliometrics on spinal cord as well as spinal cord-related literature studies have been reported on spinal cord-type cervical spondylosis, lumbar spinal stenosis, endoscopic spinal surgery, Bertolotti syndrome, Biomechanical Research on Lumbar Intervertebral Disc, osteosarcoma, multiple myeloma bone diseases, and other publications on bibliometrics, these excellent papers also suggest that there is a huge potential to explore the visual analytics literature in this field. [ 47 – 53 ]

Bladder function is also a high keyword, indicating that it is also an area of focus for researchers. The lower urinary tract consists of the bladder and the urethra, whose main function is the storage of urine and its timely elimination. This process requires precise coordination between the central nervous system (brain and spinal cord) and the peripheral nervous system. The central and peripheral nervous systems control the contractile (voiding) and relaxing (storing) states of the bladder through the regulation of complex nerve reflexes and neurotransmitters. This regulation involves multiple neural pathways and receptors, including sympathetic, parasympathetic and somatic nerves. [ 54 , 55 ] The 2 main functional units of the lower urinary-tract, the bladder and the outlet (including the bladder neck, urethral sphincter, and transverse pelvic floor muscles) second require precise coordination during the storage and voiding phases. During the storage phase, the outlet closes to prevent urine leakage while the bladder remains stationary to maintain low pressure; during the voiding phase, the outlet relaxes and the bladder contracts to facilitate urine flow. SCI disrupts normal neuroreflex circuits, leading to a loss of coordination between the bladder and the urethral sphincter, which in turn causes involuntary voiding and a reduction in the efficiency of voiding. Following SCI, the spinal voiding reflex pathway may develop new reflex patterns that result in overactive bladder, a state known as Neurogenic Detrusor Overactivity (NDO). During voiding, SCI may also lead to a loss of coordination between the detrusor (smooth muscle of the bladder wall) and the urethral sphincter, a condition known as Detrusor-Sphincter Dyssynergia (DSD), which may be associated with overexcitation of the Aδ-fiber afferent pathway. The molecular mechanism of LUTD after SCI involves a variety of factors, including changes in growth factors, ion channels, receptors and neurotransmitters. Changes in these molecules may affect neural signaling and bladder smooth muscle contractility. [ 56 , 57 ]

Based on these findings, future treatment strategies may include pharmacological interventions to modulate overactive neural pathways, biofeedback and neuromodulation techniques to restore neural control, and rehabilitation to enhance pelvic floor muscle function. The scientific basis for pelvic floor muscle rehabilitation was created by American gynecologist Arnold Kegel, who in the 1950s published the results of a 15-year study covering the use of pelvic floor exercises in patients with urinary incontinence. Kegel stated that pelvic floor muscle rehabilitation is the best way to improve muscle anatomy and dysfunction. [ 58 ]

For this field, this study has the following outlooks, firstly, with the development of robotics and computer-assisted surgery, future SCI surgeries will be more precise and safer. Robotic surgical systems may achieve higher degrees of freedom and flexibility, reduce errors in surgery, and improve the success rate of surgery. Second, the development of 5G and remote control technology will make remote surgery possible, which will greatly facilitate patients in remote areas to receive treatment from high-level hospitals. Third, with the development of genomics and personalized medicine, future treatment plans may be personalized according to patients’ genetic characteristics and individual differences, improving treatment outcomes. Lastly, rehabilitation robots and intelligent rehabilitation equipment will be more widely used, and they will be able to provide more personalized and scientific rehabilitation training to help patients recover their physical functions more quickly.

5. Limitations

CiteSpace and VOSviewer are software tools for literature analysis that assist in identifying priorities and trends in a research area. However, they have limitations and cannot entirely substitute traditional systematic search methods. Inconsistencies in the literature data might impact the credibility of atlases generated by CiteSpace. Discrepancies in data updates might result in inconsistencies between search results and the actual number of articles. Publications with a single first author may be ranked lower than those with intermediate authors, despite first-authored publications typically being more prestigious and significant. Visualization of the literature analysis aids in better comprehending the significant literature in the research area and offers a foundation for future research. This study aimed to construct a knowledge map of research findings on NB after SCI through multidimensional analysis, encompassing country, institution, original literature, authors, co-citations, and keywords.

The study covers a period of over 20 years and seeks to comprehend the evolution of the field from a long-term perspective. The analysis uncovers future trends in NB research following SCI. The findings provide valuable information for researchers and clinicians to help them determine research directions and make clinical decisions.

6. Conclusions

By analyzing the literature in this field, it was observed that the number of publications is generally increasing, with the United States and China leading in research output. Professor Jeremy B. Myers from the University of Utah had the highest number of publications, while the University of Michigan and the University of Pittsburgh were the institutions with the most publications. The journal Neurourology and Urodynamics had the highest number of articles, and common keywords included management, quality of life, and dysfunction, emphasizing key areas of focus for scholars. The majority of research in this field is clinical, with a primary focus on enhancing patients’ quality of life and reducing complications. Basic research includes modeling and interventions for NB after SCI, as well as stem cell research. Overall, the central objectives of research are to improve patients’ clinical symptoms, enhance their quality of life, and minimize complications and adverse effects.

Author contributions

Conceptualization: Jingyu Bing.

Data curation: Jingyu Bing, Haihua You.

Formal analysis: Jingyu Bing, Haihua You.

Software: Jingyu Bing, Haihua You, Yunxia Ding.

Supervision: Jingyu Bing, Haihua You, Yaowen Dai.

Validation: Jingyu Bing, Haihua You, Yaowen Dai.

Writing – original draft: Jingyu Bing, Yunxia Ding.

Writing – review & editing: Jingyu Bing, Yunxia Ding.

Visualization: Yaowen Dai, Yunxia Ding.

Project administration: Yunxia Ding.

Resources: Yunxia Ding.

Abbreviations: CWTS Centre for Science and Technology Studies NB neurogenic bladder SCI spinal cord injury WoS Web of Science.

The authors have no funding and conflicts of interest to disclose.

There were no ethical issues associated with this study, so there was no ethical committee consent to report.

The datasets generated during and/or analyzed during the current study are publicly available.

How to cite this article: Bing J, You H, Dai Y, Ding Y. Progress and research trends in neurogenic bladder after spinal cord injury bibliometric analysis based on web of science database: An observational study. Medicine 2024;103:24(e38491).

JB, HY, and YD contributed equally to this work.

Contributor Information

Jingyu Bing, Email: gdzyyj1994@163.com.

Haihua You, Email: kneeresearch1@163.com.

Yaowen Dai, Email: kneeresearch2@163.com.

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