The Significance of Type A Botulinum Toxin Ten-Point Injection Therapy in the Treatment of Chronic Pelvic Pain Caused by Muscle Spasms in Women

Abstract

Introduction and Hypothesis

This study aims to evaluate the efficacy, safety, and socioeconomic impact of botulinum toxin type A trigger point injection therapy and ten-point injection therapy for chronic pelvic pain syndrome (CPPS) caused by muscle spasm, while also exploring the efficacy and clinical significance of botulinum toxin type A ten-point injection therapy in the treatment of chronic pelvic pain.

Methods

This study conducted a retrospective analysis of patients hospitalized at a tertiary hospital from January 2024 to December 2024 who were diagnosed with chronic pelvic pain syndrome (CPPS) caused by pelvic floor muscle spasm. On the basis of the treatment protocol, these patients were divided into the trigger point pelvic floor muscle injection group and the ten-point injection therapy group, with data collected through follow-up visits or telephone interviews. The baseline characteristics of the two groups were compared, including age, body mass index (BMI), pain intensity (assessed using the Facial Pain Scale-Revised [FPS-R]), Short Form 12 Health Survey (SF-12), Hamilton Anxiety Rating Scale (HARS), and Overactive Bladder Symptom Score (OABSS). Propensity score matching (PSM) was used to balance significant differences in general characteristics between the two groups at a 1:1 ratio. Among the 91 patients, 44 received trigger point pelvic floor muscle injection therapy, and 47 received ten-point injection therapy. PSM successfully matched 64 patients, with 32 in each group.

Results

Among the 91 patients, 64 were successfully matched using the PSM method, divided into two groups of 32 patients each. The baseline characteristics of the patients in each group were well matched, with all showing (P > 0.05). Postoperative follow-up data indicated that both groups of patients showed a synchronous improvement trend in pain relief, anxiety improvement, and quality of life enhancement, with no statistically significant differences at any time point. This suggests that both injection methods have similar efficacy in improving clinical symptoms and quality of life in patients with chronic pelvic pain caused by muscle spasm.

Conclusion

Both the ten-point injection method and trigger point injection method using type A botulinum toxin demonstrate comparable safety and efficacy in treating chronic pelvic pain caused by pelvic floor muscle spasm. However, the ten-point injection method has significant advantages in terms of not relying on trigger point localization, having a relatively fixed operational process, a shorter learning curve, less time-consuming procedures, and causing less discomfort to patients, which supports its broader clinical application.

Introduction

Chronic pelvic pain (CPP) is a common noncyclical pain disorder among women, with prevalence rates ranging from 5.7% to 26.6%. Its etiology is complex and often involves multiple factors, characterized by persistent or recurrent pelvic pain lasting over 6 months that severely impacts patients’ quality of life [1]. Notably, changes in modern lifestyles—including increased sedentary habits, heightened mental stress, and biomechanical imbalances caused by poor posture—have led to a significant rise in CPP incidence [2]. However, epidemiological studies show that only about one-third of patients seek medical intervention voluntarily, suggesting that the actual disease burden may be significantly underestimated [3]. At the same time, with the improvement of social awareness of pain and the improvement of medical accessibility, the active reporting rate of patients has increased by twofold compared with 10 years ago [4], which further highlights the importance of CPP as a public health problem. Current studies show that approximately 40% of patients suffer from long-term pain due to the ineffectiveness of conventional treatment, resulting in decreased quality of life, impaired social function, and frequent mental health problems [5].

Pelvic floor muscle spasm syndrome is a clinical condition caused by dysfunction of pelvic floor muscles and nerves. Its manifestations include multi-system dysfunctions, primarily involving lower urinary tract symptoms (frequent urination, urgency, difficulty urinating, and incontinence), pelvic pain, and rectal dysfunction. Modern medical research indicates that abnormal muscle tone and neuroregulatory imbalance constitute the core pathophysiological mechanisms of this syndrome. However, clinical practice often demonstrates significant inadequacies in assessing muscular factors [6]. Muscle relaxation can alleviate spasms and reduce pain [7, 8].

Current clinical management primarily involves pharmacological analgesia (e.g., NSAIDs, opioids), physical therapy, and surgical interventions. However, these approaches have inherent limitations, including limited efficacy, high recurrence rates (over 50% within 1 year), and notable side effects such as drug dependence and surgical complications [9]. Therefore, developing safer and more applicable therapeutic strategies has become imperative.

In recent years, botulinum toxin type A (BoNT-A) has gained increasing attention in the field of chronic pain management due to its unique neuromuscular blocking and analgesic effects. This toxin not only alleviates pelvic floor muscle spasms but also reduces peripheral and central sensitization [3]. Basic research indicates that BoNT-A effectively mitigates both spastic pain and neuropathic pain by inhibiting the release of neurotransmitters such as acetylcholine and substance P [9].

When persistent spasms that are unresponsive to pelvic physical therapy occur, injection of type A botulinum toxin through trigger points is a common method for the treatment of chronic pelvic pain (CPP) caused by muscle spasms, which can effectively relieve patients’ pain and discomfort [10]. This therapeutic procedure requires imaging technologies such as ultrasound and tactile imaging to assist in precise localization, demanding skilled professionals with extensive experience to accurately identify trigger points in muscles [6]. The treatment costs are relatively high, and not all medical institutions possess the necessary equipment or staffing resources, which limits the technology’s widespread adoption. Additionally, during type A botulinum toxin injections for trigger points, repeated needle adjustments to locate optimal injection sites increase both intraoperative discomfort and procedure duration for patients.

The “Ten-Point Injection Therapy” developed by our research team represents an original innovation in this field. Rooted in pelvic floor anatomy, holistic pelvic theory, anatomical train theory, Italian fascial manipulation techniques, and the PRI pathological PEC pelvic model, this groundbreaking approach differs from conventional trigger point injections. It precisely targets ten key points within the pelvic floor muscle group for botulinum toxin A (BoNT-A) administration.

The procedure involves using a 10-ml syringe to inject into five symmetrically distributed points on both sides of the vagina, targeting the pelvic floor muscles (coccygeus, iliolector, puborectalis, pubourethra, and pubococcygeus). The injection range covers levels I, II, and III, ensuring a quick, convenient, and safe operation. This method offers advantages in surgical convenience, safety, and patient experience. It requires no imaging equipment or specific trigger point localization, follows a standardized procedure with a short learning curve and minimal operation time, effectively reducing patient discomfort. (See Fig. 1 for the injection method diagram.)

Fig. 1.

Schematic diagram of the ten-point injection method

This study aims to objectively compare the therapeutic effects of trigger point injection and ten-point injection on chronic pelvic pain caused by pelvic floor muscle spasm, to provide a theoretical basis and practical reference for optimizing the treatment plan of chronic pelvic pain caused by muscle spasm.

Materials and Methods

Study Design and Patient Population

This study conducted a retrospective analysis of patients undergoing surgical treatment for chronic pelvic pain caused by muscle spasms at the tertiary hospital. On the basis of the inpatient cases treated at the Urology Center from January to December 2024, 91 patients were selected as samples due to chronic pelvic pain syndrome (CPPS) triggered by pelvic floor muscle spasms. Inclusion criteria included: 1. Confirmed diagnosis of chronic pelvic pain (CPP) according to the 2025 EAU Chronic Pelvic Pain Guidelines; 2. Female patients; 3. Ability to complete questionnaires and cooperate with psychological and sleep assessment tools; 4. Increased resting potential in pelvic floor electromyography; 5. Detectable tender points in the vaginal area. Exclusion criteria included: 1. Pregnancy or breastfeeding; 2. History of mental illness; 3. Pain caused by other organic diseases; 4. Coagulation disorders making surgery inadvisable; 5. Refusal to participate. All participants provided written informed consent.

Method of Operation

Pain Point Injection Method: BTXA 100–300 U is dissolved in 10–30 ml of normal saline, achieving a concentration of 10 U/ml. Patients are positioned in the lithotomy position with epidural anesthesia. Preoperative pain point localization identifies three anatomical regions: anterior pelvic, middle pelvic, and posterior pelvic. The injection protocol for anterior pelvic pain targets the deep perineal muscle, urethral sphincter, and urogenital triangle. For middle pelvic pain, the injection is administered between the sacrospinous ligament and sacrospinous tuberosity, using the ischial spine as the reference point. Posterior pelvic pain is administered at the ischial tuberosity, covering the obturator muscle, rectus pubis muscle, and ilioacrococcygeus muscle. During the procedure, cystoscopy, ultrasound guidance, and X-ray localization are employed to prevent accidental injury to pelvic floor and perineal vessels. The needle depth and injection range are determined by preoperative assessment of pelvic pain points, typically 3–5 cm with a No.7 long needle. A pre-injection aspiration is performed to avoid vascular contamination. Approximately 1 ml (10 U) is injected per pain point (tender area < 1 cm²), with total injection volume not exceeding 30 ml.

Ten-point injection method: After anesthesia takes effect, the patient is positioned in lithotomy position. Place 10 ml of BTXA100U diluted in 10 ml normal saline into a 10 ml syringe. For female patients, administer 1 ml injections sequentially from the 9 o’clock direction (from deep to superficial) into the right coccygeus muscle, ilio-coccygeus muscle, pubococcygeus muscle, puborectalis muscle, and pubourethral muscle. Perform the same procedure on the left side from the 3 o’clock direction. A total of ten injection points are administered on both sides. Insert the needle of the 45° syringe completely, with a depth of approximately 3–4 cm (as shown in Fig. 1).

Post-Operative Evaluation

Both patient groups received identical postoperative care protocols, including early mobilization and discharge plans tailored to individual recovery progress. Follow-up evaluations were conducted through outpatient visits or phone calls at 1 day preoperatively, 2 weeks postoperatively, 1 month postoperatively, and 3 months postoperatively. Data collection encompassed: pain intensity (Facial Pain Scale-Rating, FPS-R), where higher scores indicate more severe conditions; 12-item Health Survey (SF-12), with lower scores reflecting greater health deterioration; Hamilton Anxiety Rating Scale (HARS); and Overactive Bladder Symptom Score (OABSS), where elevated scores correlate with more severe symptoms and diminished quality of life. These assessments primarily focused on recurrence rates or chronic pain perception, with each item scored on a 1–5 scale.

Baseline characteristics of all enrolled patients were assessed, including age, body mass index (BMI), disease duration, and abdominal surgical history. The trigger point injection group and ten-point injection group were compared in these characteristics to ensure comparability between groups at enrollment. Statistical analysis was conducted using appropriate parametric or nonparametric tests based on data distribution. A P value less than 0.05 was considered statistically significant.

Bear Fruit

This study utilized propensity score matching (PSM) to effectively balance baseline characteristics between the ten-injection therapy group (experimental group) and trigger point injection therapy group (control group). After matching, no statistically significant differences were observed in age, BMI, disease duration, or abdominal surgical history between the two groups (P > 0.05; see Table 1 for details).

Table 1.

Comparison of general characteristics between the study groups before and after propensity score matching (PSM)

Variables	Before PSM			After PSM
	The 10-point injection method treatment group	Injection method for painful points treatment group	P vaule	The 10-point injection method treatment group	Acupuncture point injection method treatment group	P vaule
Age (mean ± SD; years)	54.96 ± 11.139	55.59 ± 9.818	0.619	55.06 ± 12.649	55.91 ± 9.93	0.768
BMI	21.39 ± 2.508	23.11 ± 3.322	0.032	21.94 ± 2.449	21.88 ± 2.744	0.601
course of disease (year)	4.97 ± 5.0063	4.52 ± 5.933	0.199	4.469 ± 4.038	4.491 ± 6.5517	0.987
History of abdominal surgery (times)	1.07 ± 1.237	1.09 ± 1.537	0.785	1.09 ± 1.422	1.06 ± 1.684	0.936

Preoperative data analysis showed that there was no statistical significance between the two groups in pain intensity, psychiatric anxiety, somatic anxiety, total anxiety score, and somatic/mental health score (P > 0.05, see Table 2 for details).

Table 2.

Comprehensive analysis of preoperative data

Variables	The 10-point injection method treatment group	Group treated with trigger point injection	t price	P vaule	Mean difference (95% CI)	Effectiveness
Pain intensity before surgery	4.34 ± 2.34	4.81 ± 1.89	–0.97	0.33	(–1.52,0.58)	0.22
Preoperative psychological anxiety	7.78 ± 4.37	7.69 ± 3.39	–1.01	0.957	(–1.78,0.58)	0.31
Preoperative somatic anxiety	7.47 ± 3.71	8.72 ± 3.08	–0.74	0.162	(–1.86,0.86)	0.21
Anxiety score before surgery	15.28 ± 7.51	16.41 ± 5.69	–1.09	0.502	(–3.05,0.85)	0.27
Preoperative physical health score	16.41 ± 6.31	37.41 ± 6.04	–0.45	0.493	(–3.21,2.01)	0.1
Preoperative mental health scores	41.85 ± 7.46	41.65 ± 7.07	–0.25	0.914	(–2.68,2.08)	0.05
Preliminary OABSS score	7.63 ± 3.56	7.34 ± 3.41	–0.63	0.67	(–2.05,1.05)	0.17

Postoperative follow-up data demonstrated synchronized improvement trends in pain relief, anxiety reduction, and quality of life enhancement between the two patient groups. Specifically, at 15, 30, and 90 days post-surgery, no statistically significant differences were observed in pain intensity scores (3.44 ± 1.70 vs 2.81 ± 1.51; 2.63 ± 1.45 vs 2.56 ± 1.63; 2.53 ± 1.59 vs 2.38 ± 1.19), total anxiety scores (11.38 ± 4.56 vs 12.69 ± 4.41; 8.78 ± 3.35 vs 9.41 ± 3.25; 7.44 ± 2.93 vs 7.91 ± 2.58), or OABSS scores (6.03 ± 2.67 vs 5.97 ± 2.18; 4.56 ± 2.20 vs 4.19 ± 2.07; 4.09 ± 1.79 vs 3.66 ± 1.96) at each time point (P > 0.05, see Table 3). Notably, the ten-injection method showed comparable mental health scores at 90 days post-surgery (46.59 ± 6.30 vs 46.97 ± 6.16) to the control group (P = 0.811). These results indicate that both injection methods demonstrate similar efficacy in improving clinical symptoms and quality of life for patients with chronic pelvic pain caused by muscle spasms.

Table 3.

Changes of patients at different time periods after surgery

Variables	time point	10-point injection therapy group (x ± s)	Group treated with trigger point injection (x ± s)	Statistics (t)	Confidence interval (95% CI)	Effectiveness	P value
The intensity of the pain	15 days post-operation	3.44 ± 1.70	2.81 ± 1.51	1.36	(–0.18,1.44)	0.39	0.178
	30 days post-operation	2.63 ± 1.45	2.56 ± 1.63	0.18	(–0.72,0.86)	0.04	0.857
	Postoperative 90 days	2.53 ± 1.59	2.38 ± 1.19	0.38	(–0.65,0.95)	0.09	0.706
Psychological anxiety	15 days post-operation	4.0 ± 1.8	6.0 ± 2.1	–3.52	(–3.10,–0.90)	0.65	0.001
	30 days post-operation	3.0 ± 1.5	4.5 ± 1.7	–3.28	(–2.56,–0.44)	0.59	0.002
	Post-operative 90 days	2.0 ± 1.2	3.0 ± 1.4	–2.87	(–1.80,0.20)	0.33	0.006
somatic anxiety	15 days post-operation	5.0 ± 1.6	6.5 ± 1.9	–3.11	(–2.48,–0.52)	0.57	0.003
	30 days post-operation	3.0 ± 1.3	5.0 ± 1.5	–4.89	(0.20,3.80)	0.58	0
	Postoperative 90 days	2.0 ± 1.1	3.0 ± 1.3	–2.96	(–1.75,0.25)	0.35	0.005
Anxiety score total	15 days post-operation	11.38 ± 4.56	12.69 ± 4.41	–1.43	(–3.12,0.50)	0.3	0.156
	30 days post-operation	8.78 ± 3.35	9.41 ± 3.25	–0.74	(–2.31,1.05)	0.19	0.462
	Postoperative 90 days	7.44 ± 2.93	7.91 ± 2.58	–0.67	(–1.85,0.91)	0.17	0.502
Physical health score	15 days postoperatively	32.1 ± 5.8	35.6 ± 6.2	–2.27	(–6.12,–0.88)	0.42	0.027
	30 days post-operation	43.72 ± 6.03	43.38 ± 5.44	0.23	(15.20,25.48)	3.45	0
	Postoperative 90 days	45.2 ± 5.6	44.8 ± 5.3	0.28	(–2.56,3.24)	0.06	0.781
Mental health scores	15 days post-operation	45.6 ± 5.9	44.3 ± 5.7	0.89	(0.21,2.63)	0.42	0.376
	30 days post-operation	46.2 ± 6.1	45.1 ± 5.8	0.68	(0.20,2.64)	0.19	0.501
	Postoperative 90 days	46.59 ± 6.30	46.97 ± 6.16	–0.24	(–2.87,2.11)	0.06	0.811
OABSS score	15 days postoperatively	6.03 ± 2.67	5.97 ± 2.18	0.12	(–1.15,1.27)	0.03	0.902
	30 days post-operation	4.56 ± 2.20	4.19 ± 2.07	0.63	(–0.82,1.56)	0.18	0.531
	Postoperative 90 days	4.09 ± 1.79	3.66 ± 1.96	0.75	(–0.71,1.59)	0.24	0.448

Pain Intensity (FPS-R) Changes Dynamically

The line chart demonstrates that both groups showed a gradual decline in pain intensity postoperatively (Fig. 2a). Baseline scores were: 4.34 ± 2.34 points for the ten-point injection group and 4.81 ± 1.89 points for the trigger point injection group (P = 0.33). At 15 days postoperative, the pain score decreased to 3.44 ± 1.70 points in the ten-point group versus 2.81 ± 1.51 points in the control group (P = 0.178). By 90 days postoperative, both groups further reduced their scores to 2.53 ± 1.59 points (study group) and 2.38 ± 1.19 points (control group), though the intergroup difference remained statistically insignificant (P = 0.706). Notably, the control group achieved greater pain relief at 15 days postoperative (42.0% reduction vs. 20.7% in the study group), but this advantage gradually narrowed over time. This suggests that while the trigger point injection method may take effect faster initially, its long-term efficacy appears comparable (Fig. 2a).

Fig. 2.

Changes of parameters over time between the 10-point injection group and the trigger point injection group after treatment

Anxiety State (HAMA Score) Improvement Characteristics

The preoperative scores for psychosomatic anxiety (Fig. 2b) were 6 (on a 10-point scale) in the injection group and 8 in the trigger point injection group. After 15 days post-surgery, the study group’s score dropped to 4, while the control group’s score fell to 6—a clinically significant difference (33.3% vs. 25.0%). By 90 days post-operation, both groups had further decreased to 2 and 3 points, respectively, with the inter-group difference narrowing to 3.28% (P = 0.328).

In the somatic anxiety (Fig. 2c) study group, preoperative scores of 8 decreased to 2 points at 90 days post-surgery, representing a 75.0% reduction. The control group showed a 70.0% decrease from 10 to 3 points. However, the improvement rates differed significantly: The study group achieved a 62.5% reduction to 3 points within 30 days post-surgery, while the control group only dropped to 5 points during the same period (50.0% reduction). This suggests that the ten-point injection method may lead to earlier improvement in somatic symptoms.

The total score of HAMA (Fig. 2d) decreased from 15.28 ± 7.51 to 7.44 ± 2.93 in the study group, and decreased from 16.41 ± 5.69 to 7.91 ± 2.58 in the control group, with a decrease of 51.3% and 51.8%, respectively. The dynamic curves were highly overlapping (P = 0.502), indicating that the two methods had the same effect on the improvement of overall anxiety.

Changes in Physical and Mental Health Indicators (PCS and MCS)

The Physical Composed Score (PCS) (Fig. 2e) showed a significant improvement from 16.41 ± 6.31 to 43.72 ± 6.03 in the study group, and from 37.41 ± 6.04 to 43.38 ± 5.44 in the control group. The study group demonstrated a significant increase before 30 days post-surgery (Δ27.31 vs. Δ6.97), but the two groups converged by 90 days (P = 0.914), indicating that the ten-injection method showed more pronounced early improvement in physical function.

The mental health scores (MCS) (Fig. 2f) increased from approximately 41 points to 46 points in both groups. The study group showed a rapid increase of Δ4.74 points within 15 days post-surgery, while the control group only showed a rise of Δ3.32 points during the same period. However, the difference disappeared by 90 days (46.59 ± 6.30 vs. 46.97 ± 6.16 points, P = 0.811), indicating that the ten-injection method may be more beneficial for psychological adjustment in the short term.

OABSS Score Changes (Fig. 2g)

The improvement trend of the two groups in urinary incontinence scores was consistent, both dropping to 3.66 ± 1.96 points 90 days post-surgery. However, the ten-point injection group showed a faster decline in scores at 30 days post-operation (4.19 ± 2.07 vs. 4.09 ± 1.79 points, P = 0.488), which may be related to the broader pelvic floor muscle tone regulation achieved by the ten-point injection method. However, this difference was not statistically significant.

The Line Chart Reveals the Three-Stage Characteristics of the Two Groups of Efficacy

The postoperative 15-day injection of trigger points showed faster improvement in pain, psychological anxiety and OABSS scores, which may be related to the precise action on trigger points and rapid suppression of local abnormal nerve impulses [11].

The 10-point injection group showed better improvement in somatic anxiety, PCS and MCS scores than the trigger point injection group after 30 days, indicating that the 10-point injection had more significant improvement in somatic health and mental health.

All the differences between the two groups disappeared after 90 days, and both groups reflected the time decay of botulinum toxin effect (Fig. 2a–g).

Discussion

The pathogenesis of CPP involves the interaction of multiple factors, and its core lies in the abnormal release of acetylcholine at the motor terminal plate of nerve endings. When the release of acetylcholine continues to increase, it will cause sustained contraction of muscle fibers, resulting in local bleeding and pain symptoms [12].

In women, high abdominal pressure caused by pregnancy and childbirth may lead to trauma or chronic strain in the pelvic floor muscles. Combined with persistent irritation from pelvic inflammatory disease, these factors collectively trigger abnormal acetylcholine release at the motor endplates of nerve endings, ultimately resulting in pathological spasms of the pelvic floor muscles and fascia.

Anatomical studies reveal that approximately half of the nerve fibers in the pelvic floor region are sensory nerves, with 43% possessing pain-sensing capabilities. These free nerve endings are primarily distributed along small muscular arteries and connective tissue peripheries, directly exposed to arterial blood vessels and interstitial fluid, making them highly sensitive to biochemical stimuli. When pain receptors are activated, neuropeptides within them are released into adjacent tissues, triggering vasodilation and increased vascular permeability. Notably, pathological stimuli not only directly affect receptors but also induce endogenous pain mediators in surrounding tissues, creating a vicious cycle of pain hypersensitivity. This mechanism ultimately leads to sustained generation and amplification of pain signals in the pelvic floor region [13, 14].

Botulinum toxin type A (BoNT-A), due to its unique neuromuscular blocking and pain regulation effects, can not only relieve the spasm of pelvic floor muscles but also reduce peripheral and central sensitization, and has gradually attracted attention in the field of chronic pain [15].

This study divided 91 patients into two groups based on injection methods: the botulinum toxin ten-injection group and the trigger point injection group. No adverse reactions such as urinary retention or difficulty urinating were observed during treatment and follow-up periods. Postoperative evaluations revealed reduced pelvic floor pain scores, improved quality of life, decreased anxiety levels, and lower urinary incontinence scores in both groups, with no statistically significant differences at any time points. These findings indicate that the BTXA ten-injection method demonstrates comparable efficacy to trigger point injection in alleviating chronic pelvic pain symptoms and enhancing quality of life caused by muscle spasms. Our analysis suggests the mechanism of action involves multiple factors:

The therapeutic logic under the pelvic floor overall theory: CPP originates from different pelvic organs. The pelvic floor is composed of muscles, fascia, and connective tissue [16]. CPP may only be a manifestation of myalgia, and the cause of some pain points may originate from completely asymptomatic silent areas rather than local tender points themselves [17]. Therefore, the clinical treatment strategy should be adjusted to inject botulinum toxin into these distal silent areas, rather than directly injecting it into the dominant trigger point, which can also achieve the expected therapeutic effect.

The traditional “muscle isolation theory” approach to explaining muscle function focuses on isolated skeletal muscles. By dissecting their anatomical structures, severing neural and vascular connections, and disconnecting adjacent tissues, this perspective often overlooks how individual muscles interact through fascial networks that maintain functional integrity. In reality, the pelvic floor muscles do not operate in isolation but form a dynamically coordinated “train system” through myofascial chains [18]. The injection method of kinetic pain is to relieve the spasm of specific muscles by precisely blocking the local hyperactive neuromuscular junction and inhibiting the abnormal release of acetylcholine [19]. The synergy between the two approaches may stem from botulinum toxin’s universal inhibitory effect on neuromuscular transmission [9]. Regardless of injection strategies, both methods ultimately restore pelvic floor muscle coordination by suppressing abnormal electrical activity. Therefore, we should not view individual muscles in isolation but consider them as functional complexes. Both approaches demonstrate a bidirectional interaction of “local intervention and holistic regulation,” which may be the core mechanism underlying their comparable therapeutic efficacy.

Muscle Tension Theory and Restoration of Mechanical Balance: Pelvic floor dysfunction is often accompanied by muscle tension imbalance. For instance, high-tension states may cause ischemic pain, while low-tension conditions trigger mechanical compensation mechanisms to maintain basic physiological functions [20]. Botulinum toxin temporarily reduces muscle tension through chemical denervation effects, breaking the vicious cycle of “spasm-pain-spasm” and promoting the remodeling of mechanical balance. Injections of kinetic pain are aimed at areas with abnormal local tension, and may achieve [21] local relaxation by precisely regulating key mechanical nodes [19]; while the ten-point rule distributes the tension load of deep pelvic floor muscle groups through multi-point injections, and reconstructs the mechanical balance of pelvic floor muscle groups as a whole.

Pelvic Floor Anatomy: The pelvic floor muscles are directly attached to the complete bony framework formed by the ilium, pubis, and ischium through direct attachment or a combination of bony and connective tissue attachments. Their proper function relies heavily on precise anatomical positioning and stability of the pelvic bones. Any displacement of individual attachment points or abnormal tension can trigger compensatory neural inhibition, which may explain the anatomical basis for similar therapeutic effects across different injection sites [22].

Limitations and Prospects of this Study

Limitations: While propensity score matching effectively balanced baseline variables including age, BMI, disease duration, and abdominal surgical history (P > 0.05), we acknowledge the potential for residual confounding factors. Unmeasured clinical variables such as pain sensitivity, hormonal levels, or neuromuscular function differences may influence efficacy assessment, requiring future prospective studies with more precise covariate control for validation. Additionally, our limited sample size and non-blind design may introduce operator bias. The 3-month observation period only reflects midterm effects of botulinum toxin, with further observation needed for safety and long-term efficacy. Although using internationally recognized assessment tools, the Facial Pain Scale (FPS) has limited sensitivity to detect minor pain changes, potentially masking subtle therapeutic differences. While the 10-point injection method theoretically reduces medical costs (by eliminating ultrasound fees), comprehensive cost comparisons between the two approaches in terms of consumables, procedure duration, and complication management require additional health economics evaluation.

This study systematically evaluated multidimensional indicators (including pain intensity, quality of life, psychological state, and bladder function) at four time points: preoperative, 15 days postoperative, 1 month postoperative, and 3 months postoperative. The results demonstrated comparable clinical efficacy between the ten-point injection method and trigger point injection therapy in treating chronic pelvic pain caused by muscle spasms. This finding provides new perspectives for optimizing treatment strategies. Notably, the ten-point injection method’s simplicity (requiring no imaging guidance) significantly lowers surgical barriers and treatment costs, which holds significant public health value for promoting botulinum toxin (BoNT) therapy adoption in primary healthcare institutions.

Future Research

Although the 3-month follow-up data showed stable efficacy, there were individual differences in the duration of botulinum toxin action. It is recommended to extend the observation to 6–12 months to clarify the potential differences in the duration of efficacy maintenance between the two methods.

The mechanism underlying the similar outcomes of the two injection methods remains unclear. Basic research could compare the inhibitory effects of different injection modes on acetylcholine release at neuromuscular junctions in the pelvic floor muscles, or utilize diffusion-weighted magnetic resonance imaging (DWI-MRI) to visualize differences in botulinum toxin distribution within the myofascial layer.

It is necessary to carry out clinical trials to verify the universality of the standardized operation mode of 10-point injection in this study for other pelvic floor dysfunction diseases (such as overactive bladder and fecal incontinence).

Author Contributions

Yang: Protocol/project development, Data analysis, Data collection or management, Manuscript writing/editing.

Guan: Protocol/project development, Manuscript writing/editing.

Ma: Data analysis, Data collection or management, Manuscript writing/editing.

Luo: Data analysis, Data collection or management.

Zhang: Data collection or management.

Wang: Data collection or management.

Yang: Data collection or management.

Zhang:Data collection or management.

Data Availability

All de-identified data supporting this observational longitudinal study—including participants’ baseline characteristics, repeated follow-up measurements (e.g., clinical indices, questionnaire scores), and long-term outcome records—are publicly available. The data have been anonymized to protect participants’ privacy and have obtained ethical approval from the Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University (Approval No.: K202505-22). No access restrictions apply. This study is exempt from clinical trial registration.

Declarations

Ethical Approval

This study was approved by the Medical Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University (Approval No. K202505-22).

Conflict of interest

The authors declare that they have no known competing financial interests or personal relationships.