Comparison of clinical efficacy of Laennec’s capsule approach and traditional approach in patients with gallbladder stones complicated by acute cholecystitis

Abstract

Objective

To assess the application of laparoscopic cholecystectomy (LC), such as safety, feasibility, and advantages via Laennec’s capsule in patients with gallbladder stones complicated by acute cholecystitis.

Methods

A total of 120 patients with gallbladder stones and acute cholecystitis who underwent surgery at Lishui District People’s Hospital, Nanjing, from June 2022 to August 2024 were retrospectively assessed. Patients were divided into the following two groups: the experimental (LC via the Laennec’s capsule, n = 60) and control groups (conventional LC with Calot’s triangle dissection, n = 60). The parameters such as the intraoperative blood loss, operative time, duration of postoperative drainage, length of hospital stay, bile duct injury rate, conversion to open surgery, the rate of postoperative complications, use of bioabsorbable clips, and gastrointestinal recovery were recorded. The enzyme-linked immunosorbent assay was used to measure serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels.

Results

The experimental group demonstrated significantly lower intraoperative blood loss, shorter duration of postoperative drainage, faster gastrointestinal recovery, shorter hospital stay, lower postoperative pain scores, and reduced use of bioabsorbable clips than the control group (p < 0.05). Serum IL-6 and CRP levels in the experimental group were significantly lower at 24 h postoperatively than those in the control group. However, no statistically significant differences were observed between the experimental and control groups in terms of baseline characteristics, operative time, conversion to open surgery rate, or postoperative complication rate (p > 0.05).

Conclusion

LC via the Laennec’s capsule offers advantages by accelerating gastrointestinal recovery, reducing the postoperative inflammatory response, and improving quality of life in the treatment of gallbladder stone patients with acute cholecystitis.

Introduction

Laparoscopic cholecystectomy (LC) has become the gold-standard surgical approach for gallbladder diseases in recent years, particularly during the acute inflammatory phase. LC is the primary treatment modality for patients with acute cholecystitis [7]. However, the severity of clinical presentation differs among patients with cholecystitis. LC is generally considered a challenging procedure for patients with grade II acute cholecystitis, as defined by the Tokyo Guidelines (2018) [5]. Inflammation can lead to fibrosis or scarring within Calot’s triangle in cases of moderate to severe acute cholecystitis, causing obscuration of vascular and biliary structures, and presenting significant technical challenges for surgeons, particularly when anatomical variations are encountered [8, 14]. Under such conditions, the feasibility and safety of surgery pose a major challenge for surgeons. When laparoscopic surgery is performed using the conventional anterolateral Calot’s triangle approach, involving dissection around the cystic duct, the risk of injury to adjacent vascular and biliary structures is enhanced, potentially leading to destructive results and poor patient outcomes [3]. Therefore, based on the disease characteristics of acute cholecystitis, a scientifically sound and reasonable surgical approach must be identified for critical research importance. Laennec’s intrinsic membrane covers the entire hepatic surface and surrounds the intrahepatic Glisson’s pedicle and hepatic veins, providing a precise anatomical plane for laparoscopic hepatectomy [10, 20]. A novel surgical technique has been introduced by our institution involving initial dissection from the dorsolateral aspect of the lower third of the gallbladder body using an electrocautery hook, creating a plane between the Laennec’s membrane and an inner subserosal layer of the gallbladder. The lower third of the body of the gallbladder is then detached and transected, permitting traction-assisted elongation of the neck and full exposure of Calot’s triangle before its subsequent dissection. This technique aims to minimize the risk of vascular and biliary injury and is termed the “Laennec’s membrane body-first approach.” Therefore, this study aimed to investigate the application of LC via Laennec’s capsule in patients with gallbladder stones complicated by acute cholecystitis, further comparing its outcomes with those of conventional LC. The study findings will serve as a basis for establishing a surgical model for acute cholecystitis.

Compared with the Fundus First Approach, the main advantage of the Laennec pouch method lies in providing a clearer anatomical view and more precise localization of the cystic duct and cystic artery, effectively reducing intraoperative bleeding and the risk of bile duct injury. Additionally, the Laennec pouch method helps reduce postoperative complications, such as bile leakage, and accelerates gastrointestinal recovery, thus shortening the length of hospital stay. This method is more suitable for managing complex or acute cholecystitis cases, offering higher safety and minimally invasive benefits.

This study innovatively applies the Laennec capsule technique to laparoscopic cholecystectomy in patients with gallstones complicated by acute cholecystitis. By systematically comparing it with the traditional Calot’s triangle dissection method, the study evaluates multiple clinical outcomes including intraoperative bleeding, postoperative recovery, and inflammatory response. It is the first to clearly demonstrate that this approach can significantly shorten postoperative recovery time, reduce inflammatory reactions, and decrease postoperative complications, offering a safer, minimally invasive, and faster recovery treatment option for patients in the acute phase, with significant clinical application value.

Theoretically, this study enriches the theoretical framework of gallbladder surgery by applying the Laennec capsule technique to laparoscopic treatment of gallstones with acute cholecystitis and systematically comparing it with the traditional Calot’s triangle dissection method. It expands new concepts in minimally invasive surgical treatment for acute gallbladder inflammation and provides theoretical support for exploring safer and more efficient surgical approaches.

Practically, the study demonstrates that the Laennec capsule method offers significant advantages in reducing intraoperative bleeding, promoting postoperative recovery, and alleviating inflammatory responses. It presents a more feasible, safer, and minimally invasive surgical option for clinicians treating patients with gallstones and acute cholecystitis, showing strong potential for clinical application and playing a positive role in enhancing surgical standards and improving patient quality of life.

Materials and methods

Study design

A retrospective analysis was conducted on 120 patients with gallstones complicated by acute cholecystitis who underwent surgical treatment at Lishui District People’s Hospital of Nanjing, China, between June 2022 and August 2023. Based on the intraoperative surgical approach, patients were divided into two groups: the experimental group (laparoscopic cholecystectomy via the Laennec capsule approach) and the control group (traditional laparoscopic cholecystectomy via Calot’s triangle dissection), with 60 cases in each group. In the experimental group, there were 37 males and 23 females, aged 43–62 years, with a mean age of (52.5 ± 9.0) years. In the control group, there were 35 males and 25 females, aged 42–63 years, with a mean age of (52.2 ± 8.8) years. There was no statistically significant difference in baseline characteristics between the two groups (P > 0.05). The study was approved by the Ethics Committee of Nanjing Lishui People’s Hospital (Ethic Approval Number:2024JS1016-18) in accordance with the principles of the Declaration of Helsinki, and all of the participants provided signed informed consent.

This study adopted a randomized grouping method, assigning patients with gallstones complicated by acute cholecystitis who met the inclusion criteria into the experimental and control groups using a random number table, in order to minimize the influence of human factors on the study results.

Patient inclusion and exclusion criteria

The inclusion criteria for the study were as follows: (1) a diagnosis of gallbladder stones with acute cholecystitis (grade II) according to the Tokyo Guidelines (2018) [12]; (2) a first episode of acute cholecystitis with a symptom duration of more than 72 h; and (3) good compliance with medical instructions and the ability to undergo regular follow-up. The exclusion criteria of the study were as follows: (1) atrophic cholecystitis; (2) common bile duct stones; (3) severe acute pancreatitis; (4) diffuse peritonitis; (5) gangrenous cholecystitis or gallbladder perforation; (6) malignancy; (7) severe cardiac, hepatic, or renal failure; (8) cachexia; (9) coagulation disorders; or (10) disseminated intravascular coagulation.

Outcome measures

The surgical-related parameters recorded and compared between the experimental and control groups were as follows: intraoperative blood loss, the duration of surgery, postoperative gastrointestinal recovery time, postoperative drain tube retention time, and the length of hospital stay. The other parameters, such as the rate of conversion to open surgery (%) and the incidence of intraoperative bile duct injury (BDI) and vascular injury, were also evaluated. Postoperative complications, including postoperative pain, bile leakage, bile duct stricture, intra-abdominal abscess, and pulmonary infection were monitored.

Approximately 5 mL of venous blood was drawn from the left elbow of the patient preoperatively and at 24 h postoperatively. The blood was then centrifuged at 2000 rpm for 10 min. The supernatant (serum) was collected, and serum levels of serum interleukin-6 (IL-6) and C-reactive protein (CRP) were measured using an enzyme-linked immunosorbent assay (ELISA) kit (China).

Treatment regimen

Both the experimental and control groups underwent surgery under general anesthesia using endotracheal intubation. Routine preoperative preparations were made, including the assessment of liver and kidney functions and routine blood and imaging examinations such as ultrasound, computed tomography (CT), and magnetic resonance cholangiopancreatography, to exclude any surgical contraindications. Patients were instructed to fast for 8 h before surgery. Both groups were administered standard antibiotic therapy to prevent infection postoperatively, and abdominal drainage was monitored. Post-recovery of the gastrointestinal function, a low-fat liquid diet was initiated among the patients, gradually transitioning to a low-fat solid diet.

In this study, all patients routinely received abdominal drainage tube placement to allow timely postoperative monitoring of bile drainage and to detect complications such as bile leakage or bleeding. The criteria for drainage tube placement included intraoperative findings such as gallbladder perforation, bleeding, bile contamination, unclear operative field, or a high risk of postoperative complications. Postoperatively, the volume and characteristics of the drainage fluid were assessed daily. If the drainage volume was less than 30 mL, the fluid appeared clear and odorless, and abdominal ultrasound showed no abnormal effusion, the drainage tube could be considered for removal to ensure safety and promote early recovery.

In this study, the number of absorbable clips used was determined based on the intraoperative anatomical conditions of the cystic artery and cystic duct, as well as the need for hemostasis. If the anatomy was clear and there was no significant bleeding, typically one clip was applied to each structure. If the anatomy was unclear or there was a risk of bleeding, additional clips were used as needed to ensure intraoperative safety and to prevent postoperative complications such as bleeding or bile leakage.

In this study, all surgeries were performed by the same experienced lead surgeon to ensure consistency and standardization of the surgical procedures. This surgeon has many years of experience in laparoscopic cholecystectomy and is able to effectively control intraoperative variables, minimizing the impact of inter-surgeon experience differences on the study results.

Control group

The control group underwent LC using the three-port method for the removal of the gallbladder. An intra-abdominal pressure of 11–13 kPa was maintained, and the pneumoperitoneum was established through an umbilical incision using a pneumoperitoneum needle. Additional operative ports were established after inserting the camera, and instruments were introduced to investigate the abdominal cavity, separate the adhesions, and detect the cystic triangle. The anterior and posterior layers of the peritoneum at the gallbladder triangle were completely exposed using an electrocautery hook after the adhesions were cleared. The cystic artery and duct were identified, ligated, and divided. The gallbladder bed was then cautiously dissected. A retrograde dissection was performed in cases of difficulty in the separation of the cystic triangle, starting from the gallbladder fundus and extending toward the cystic triangle. Following this, the cystic duct and blood vessels were ligated and divided. After hemostasis was achieved in the gallbladder bed, the surgical area was irrigated, and a drain was placed under the right lobe of the liver. When any difficulty was encountered during the procedure, such as an inability to detect critical structures or arrest bleeding, to avoid forcible dissection or resection that could lead to severe complications, open surgery was promptly performed.

Experimental group

The experimental group underwent LC through the “Laennec membrane” approach. The pneumoperitoneum was established through the umbilical incision after general intravenous anesthesia, and the surgical instruments were introduced using the conventional three-port method. A cautery hook was used to open the gallbladder serosal layer, separating the outer and inner layers of the serosal layer down to the level of the Laennec membrane in the lower third of the gallbladder body on the dorsal side (Fig. 1A-B). The separation was carried out bluntly and sharply between the inner layer of the serosal layer and the Laennec membrane, exposing the lower third of the gallbladder body. Once this was completed, a retractor was used to pull and fully expose the gallbladder triangle. After adequate exposure, the gallbladder triangle was dissected, and when the critical view of safety (CVS) criteria were met, the relationship of the three ports was re-confirmed. Absorbable ligating clips were then used to ligate and divide the cystic artery and cystic duct (Fig. 1C-E). The gallbladder was carefully dissected from the space between the inner layer of the serosal layer and the Laennec membrane, and hemostasis was ensured. A drainage tube was then placed under the right lobe of the liver, exiting through the right Trocar port.

Fig. 1.

Schematic diagram of cholecystectomy through the Laennec membrane approach in the patient with a grade II acute cholecystitis. A: A cautery hook was used to open the gallbladder serosal layer, separating the outer and inner layers of the serosal layer down to the level of the Laennec membrane in the lower third of the gallbladder body on the dorsal side. B: The red arrow indicates the Laennec membrane, the blue arrow indicates the inner layer of the subserosal layer, and the yellow arrow shows the blunt and sharp dissection of the lower third of the gallbladder body between the Laennec membrane and inner layer of the subserosal layer. C-E: After creating a passage to fully expose the gallbladder triangle, the gallbladder neck is retracted using sling traction. The dissection of the gallbladder triangle is performed until the critical view of safety (CVS) criteria are fulfilled, followed by ligation and division of the cystic artery and duct

Postoperative complication assessment

Routine examinations will be conducted after surgery, including blood routine CRP, interleukin-1, liver function, and electrolyte levels. Use Visual Analog Scale (VAS) to assess pain 24 h before and after surgery. In order to assess the condition and determine the presence of complications such as bile leakage, bleeding, abdominal infection, or biliary obstruction/stenosis, ultrasound examination was performed. Before removing the drainage tube, a follow-up color Doppler ultrasound is typically performed on the second or third postoperative day. The tube is removed when the patient’s drainage volume significantly decreases to below 20 ml, or if the drainage volume remains high but shows no abnormal characteristics. The follow-up ultrasound before tube removal helps to determine whether there is any drainage obstruction or leakage, thereby ensuring the safety of each patient. The cost of the ultrasound is disclosed in advance. This study focuses on severe cholangitis, and compared to other approaches, this method does not increase the overall cost but results in fewer complications, ultimately helping to reduce healthcare insurance expenses.

Statistical analysis

SPSS 26.0 software was used to perform statistical analysis. The results were presented as mean ± standard deviation for normally distributed data, and independent sample t-tests were used for intergroup comparisons. The results were expressed as median (interquartile range) [M (Q1, Q3)] for data that did not follow a normal distribution, and intergroup comparisons were performed using the Mann-Whitney U test. The results were presented as frequency (percentage) for categorical data, and the Chi-square test or Fisher’s exact test was used for intergroup comparisons. Statistical significance was set at P < 0.05.

Results

Demographic information of patients

The general patient information is presented in Table 1. The average age of patients in the experimental group was 54.85 ± 15.07 years, with 25 men and 35 women, and that of patients in the control group was 50.53 ± 12.53 years, with 25 men and 35 women. No significant differences in general data, including age, sex, stone diameter, number, and gallbladder triangle adhesion were noted, between the two groups (p > 0.05, Table 1).

Table 1.

Demographic information of patients in the experimental and control groups

Demographic information	Experimental Group (n = 60)	Control group (n = 60)	χ2/t/Z	P
Gender			-	-
Male	25(41.67)	25(41.67)
Female	35(58.33)	35(58.33)
Age	54.85 ± 15.07	50.53 ± 12.53	1.706	0.091
Stone Diameter (cm)	1.55(1.00–2.00)	1.75(0.80–2.22)	−0.404	0.686
Stone Quantity			0.511	0.871
1	14(23.33)	13(21.67)
2	2(3.33)	1(1.67)
> 3	44(73.33)	46(76.67)
Gallbladder Triangle Adhesion			0.320	0.572
No	21(35.00)	24(40.00)
Yes	39(65.00)	36(60.00)

Comparison of Operation-Related indicators between the two groups

In the experimental group, the intraoperative blood loss was significantly lower than that in the control group (5 vs. 10 mL), with a statistically significant difference (p < 0.05). The postoperative drainage tube retention time and hospital stay were significantly shorter in the experimental group than those in the control group, with statistically significant differences (p < 0.05). No BDI injuries or conversions to open surgery were observed in the experimental group, with only one case of subtotal cholecystectomy. There was one case of BDI injury, one case of vascular injury, and two cases of conversion to open surgery in the control group. No patients in either group experienced complications such as bile duct stenosis, abdominal abscess, or lung infection. The two groups’ conversion rate to open surgery demonstrated no statistically significant difference (p > 0.05). No significant differences in the overall perioperative complication rates were observed between the experimental and control groups (p > 0.05); however, the incidence of biliary complications (such as BDI and vascular injury) was 0% in the experimental group, which was lower than the 3.33% incidence in the control group. No cases of bile duct stenosis, residual gallbladder, or residual gallbladder stone were noted during the follow-up period of 6–8 months in all patients in the experimental group. The experimental group had significantly lower pain scores on POD 1 than that in the control group (p < 0.05). However, no significant difference in the operation time was noted between the two groups (p > 0.05). Considering the postoperative gastrointestinal recovery, the experimental group had a shorter time to first flatus (17.5 h) than that of the control group (29 h), with a statistically significant difference (p < 0.05).

Comparison of inflammatory factor levels before and after surgery between the two groups

Preoperatively, no statistically significant differences in serum IL-6 and CRP levels were observed between the two groups (p > 0.05). However, serum IL-6 and CRP levels were higher in both groups 24 h postoperatively compared to the preoperative levels. The serum IL-6 and CRP levels were significantly lower in the experimental group than those in the control group (p < 0.05, Table 2).

Table 2.

Comparison of the operation-related indicators between the two groups

Indicators	Experimental group (n = 60)	Control group (n = 60)	χ2/t/Z	P
Blood Loss (ml)	5.00(5.00,10.00)	10.00(5.00,10.00)	−3.910	< 0.001
Surgical Duration (min)	60.00(50.00,70.00)	60.00(50.00,75.00)	−0.759	0.448
Gas Expulsion Time (h)	17.50(11.25,24.00)	29.00(17.75,40.75)	−3.941	< 0.001
Drainage Volume (ml)	40.00(10.00,100.00)	47.50(26.25,100.00)	−1.295	0.195
Drainage Duration (days)	1.00(1.00,4.00)	2.00(2.00,4.00)	−3.674	< 0.001
Use of Biological Clips	4.00(4.00,5.00)	5.00(4.00,5.00)	−2.099	0.036
Hospital Stay Duration (days)	6.00(5.00,7.00)	7.00(6.00,8.00)	−2.000	0.045
Preoperative CRP	7.73(1.35,34.78)	5.17(3.46,11.42)	−0.037	0.971
Postoperative CRP	28.84(15.16,67.85)	37.35(32.5,65.41)	−2.756	0.006
Preoperative IL-6	9.47(2.94,19.55)	7.00(3.82,10.57)	−0.194	0.846
Postoperative IL-6	17.31(8.37,38.21)	20.85(16.43,32.87)	−2.483	0.013
Preoperative Pain Score	3.00(2.00,5.00)	3.00(2.00,5.00)	−1.218	0.223
Postoperative Pain Score	2.00(2.00,3.00)	3.00(2.00,3.00)	−2.545	0.011
Bile Duct Injury	0(0.00)	1(1.67)	-	1.000
Complication Rate	0(0.00)	2(3.33)	0.508	0.476
Conversion to Open Surgery	0(0.00)	2(3.33)	0.508	0.476

Discussion

In LC, the cystic duct and artery may be misidentified owing to the unclear anatomical layers of the Calot’s triangle, resulting in bleeding and potentially severe BDI. Therefore, a widely accepted safe method to expose Calot’s triangle is by achieving a key safe view (CVS) before transecting the cystic duct [2, 13]. However, dense fibrous adhesions may form within the Calot’s triangle in cases of severe cholecystitis or when stones are impacted at the neck of the gallbladder, complicating dissection and increasing the risk of BDI [11].

In the past, surgeons could opt for retrograde cholecystectomy on encountering difficult cholecystectomy, avoiding starting from the dense Calot’s triangle to prevent BDI. However, initiating from the gallbladder’s base to the Calot’s triangle requires a longer dissection path. Moreover, if the cystic artery has not been ligated earlier, there is a higher risk of bleeding. This can result in injuries to the superficial portal vein branches, causing intraoperative and postoperative hemorrhage, or damage to the superficial bile ducts, potentially leading to postoperative bile leakage [16]. Some scholars have attempted to use Rouvière’s hook approach, which involves separating the gallbladder’s submucosal inner and outer layers, reducing the risk of BDI. This technique has a higher success rate in mild inflammation, and when the layers of the gallbladder are relatively clear. However, in severe inflammation cases, where the submucosal inner and outer layers merge, locating the space for dissection becomes challenging, possibly leading to the bile duct and vascular injuries [15]. Recently, the “gallbladder plate” approach for cholecystectomy has been explored. The theoretical basis is that the fibrous tissue layer of the gallbladder fundus and cystic duct continues anatomically with the hilar plate of the liver with space between them. By approaching through the gallbladder plate, the bare area of the Calot’s triangle can be expanded, confirming the “single duct,” which can be interpreted as partial retrograde cholecystectomy. Thus, the safety and efficiency of both traditional “retrograde” and “antegrade” cholecystectomy are combined [18].

The method used in this study is an improvisation of the gallbladder plate approach. Specifically, it comprises accessing the middle and lower third of the gallbladder body, creating a tunneled window from the front of the Laennec’s capsule, and then suspending the neck of the gallbladder. This approach allows for a thorough exposure of the Calot’s triangle and reduces the risk of injury to anatomical variations of the cystic duct, such as those connecting the common hepatic duct, right hepatic duct, right accessory hepatic duct, or both high and low bile duct junctions, and even the rare connection with the anomalous accessory hepatic duct. In this study, Laennec’s capsule approach revealed that many cases of cystic duct “high junction” involved shortening of the cystic duct in the hilar area. By dissecting closely along Laennec’s capsule toward the common bile duct, similar to the “lowering the hilar plate” technique, the space between Laennec’s capsule and the inner layer of the gallbladder serosal layer can be exposed. This effectively moves the cystic duct-cutting plane away from the extrahepatic bile ducts. Simultaneously, this fine dissection of the Calot’s triangle anatomy improves the identification of ductal structures, reduces intraoperative blood loss, and minimizes the total amount of postoperative drainage. Consequently, there is less postoperative pain, the blind use of bioabsorbable clips is avoided, and the operation time is not extended. The results from this study indicate that the laparoscopic Laennec’s capsule approach for cholecystectomy can significantly reduce intraoperative bleeding, shorten postoperative recovery time, and improve overall patient outcomes. The observation group had shorter time for gastrointestinal recovery, less intraoperative blood loss, lower postoperative drainage, and shorter hospital stays than those in the control group.

IL-6 and CRP are the indicators of the inflammatory response of the body and are closely associated with the severity of acute cholecystitis [9]. However, various immune cells, such as macrophages, neutrophils, and natural killer cells are activated by surgical trauma-induced tissue damage. Once activated, these cells initiate the production of cytokines like IL-6 and CRP, directly contributing to systemic inflammation [6]. Therefore, reducing surgery-related inflammation can help in improvement of the surgical outcomes and accelerate postoperative recovery [17]. In this study, the inflammatory factor levels 24 h after surgery were significantly lower in the observation group than those in the control group, suggesting that Laennec’s capsule approach can reduce postoperative inflammatory responses. During the acute phase of cholecystitis, the inner and outer layers of the gallbladder serosal layer fuse owing to inflammation, causing the gap to disappear. In contrast, Laennec’s capsule is less affected by inflammation. When Laennec’s capsule approach is used, the surgeon accesses the membrane layer, which is without a vascular zone, increasing the distance of the dissection plane for the cystic duct from the extrahepatic bile ducts [1]. This approach potentially reduces surgical trauma and the stress response of the patient. Complications such as BDIs, vascular injuries, and bile leaks are common in LC, with an incidence rate of 3.33% in the control group. The main causes of BDI include inflammatory adhesions in the Calot’s triangle, unclear anatomy, intraoperative bleeding, excessive traction of the bile duct, and inexperience or carelessness of the operator [4, 19]. In this study, “Laennec’s capsule body-first approach” extended the cystic duct, completely exposed the Calot’s triangle, and considered the key path to reach the CVS. Dissecting the membrane layer, which inherently lacks blood vessels and bile ducts, reduced the risk of BDI caused by damage to the cystic artery or blind clipping to arrest bleeding. This technique may prevent common complications and enhance patient outcomes.

However, this study has a few limitations. First, information on the patient’s chronic conditions, including diabetes, hypertension, heart failure, and chronic obstructive pulmonary disease, was not collected. These could increase the likelihood of postoperative infections and other complications, thus affecting the outcomes related to postoperative complications. Second, this study had a relatively small sample size, and the conclusions require further validation through larger-scale, long-term studies.

Conclusion

The study found that using the Laennec membrane approach in acute cholecystectomy is more advantageous than the conventional LC in reducing postoperative complications, enhancing postoperative recovery, lessening postoperative pain responses, and decreasing BDI.

Author contributions

Z.Y. conceptualized and designed the study and drafted the initial manuscript. Z.Y. and R.X. collected the data and carried out the initial analyses. H. Z. critically reviewed the manuscript for important intellectual content. All authors approved the fnal manuscript as submitted and agreed to be accountable for all aspects of the work.

Funding

No funding was received for this article.

Data availability

All data used during the study are available from the corresponding author by reasonable request.

Declarations

Ethics approval and consent to participate

The study was approved by the Ethics Committee of Nanjing Lishui People’s Hospital (Ethic Approval Number:2024JS1016-18) in accordance with the principles of the Declaration of Helsinki, and all of the participants provided signed informed consent.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Disclosure statement

No competing financial interests exist.