Laparoscopic adhesiolysis for adhesion-related chronic abdominal and pelvic pain after gynaecological and general surgery: an updated meta-analysis and systematic review

Abstract

Background

Chronic pain resulting from postoperative adhesions represents a significant clinical concern due to its substantial impact on patient quality of life; however, optimal therapeutic management remains contentious. This systematic review and meta-analysis aimed to evaluate the efficacy of laparoscopic adhesiolysis in alleviating chronic pain attributable to postoperative adhesions, and to assess the influence of adhesion barriers on treatment outcomes.

Methods

A comprehensive systematic review was conducted by searching PubMed, Embase, and Web of Science from database inception through August 2025. Studies reporting pain improvement as the primary outcome, along with safety outcomes (including complication incidence and mortality), were eligible for inclusion. Pooled estimates were calculated using a random-effects model, and heterogeneity was quantified employing the I² statistic..

Results

A total of 30 studies involving 1,450 patients were included in the systematic review.

In 27 single-arm observational studies (n = 1,150), laparoscopic adhesiolysis was associated with a pooled pain improvement rate of 67.3% (95% CI 57.5–76.2%), with substantial heterogeneity (I² = 91%). In contrast, pooled analysis of four randomized controlled trials (n = 271) demonstrated no statistically significant difference in pain improvement between laparoscopic adhesiolysis and diagnostic laparoscopy alone (38.9% vs 36.2%; risk ratio 1.05, 95% CI 0.61–1.83).

Conclusion

Although observational studies report relatively high rates of pain improvement, these findings should be interpreted as descriptive and hypothesis-generating. The highest level of available evidence from randomized controlled trials does not demonstrate a clinically meaningful benefit of laparoscopic adhesiolysis over diagnostic laparoscopy alone.

Trial registration

PROSPERO CRD42023478049.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-026-03631-7.

Introduction

Chronic pelvic and abdominal pain severely affects millions of people, particularly women. In low- and middle-income countries, chronic pelvic pain affects 11% of the general adult population and 7% of the elderly [1]. In women, prevalence ranges from 5% to 25% [2, 3]. In the United State [4], approximately $881.5 million is spent annually on outpatient treatment, while the UK spends an estimated £158 million on similar care [5]. Surgery-induced adhesions are the primary cause of chronic abdominal or pelvic pain [6].

Adhesions develop in 90% of patients after open abdominal surgery and 70% after laparoscopy [7, 8]. They can lead to chronic abdominal pain and adhesive small bowel obstruction [9, 10]. Postoperative adhesions are a common cause of chronic pain [11]. A study of 198 patients who underwent lower gastrointestinal surgery found that 40% reported chronic abdominal pain [12]. Additionally, a meta-analysis by ten Broek et al. indicated that adhesions were identified as the likely cause of pain in 57% of patients who underwent diagnostic laparoscopy following prior surgery [10].

Laparoscopic adhesiolysis is a common treatment [13], though its efficacy and safety remain debated, particularly regarding the use of barriers. In 2017, van den Beukel et al. evaluated the efficacy and risks of laparoscopic adhesiolysis for chronic pain caused by post-surgical adhesions in a meta-analysis [14]. The study was limited by a small number of included studies, with only two RCTs, and short follow-up periods (6–12 months) in most non-randomized studies, hindering long-term assessment. However, advances in non-invasive diagnostic techniques have improved detection of adhesion-related pain [15].

Chronic pain caused by postoperative adhesions is an important and challenging clinical problem, but the evidence regarding the therapeutic benefit of adhesiolysis remains inconsistent. A clear gap exists in the lack of systematic comparisons between laparoscopic adhesiolysis and diagnostic laparoscopy alone for pain relief, as well as limited high-quality evidence on the role of adhesion barriers.​

This study aims to evaluate the effectiveness of laparoscopic adhesiolysis in relieving adhesion-related chronic postoperative pain through a systematic review and meta-analysis, and to further explore the impact of adhesion barriers on treatment outcomes.

Material and methods

Protocol registration

The full review protocol was registered with PROSPERO under registration number CRD42023478049. This study was conducted and reported in strict accordance with the PRISMA 2020 guidelines [16].

Ethics approval and consent to participate

This study is a systematic review and meta-analysis based exclusively on previously published literature. No human participants or animals were directly involved, and therefore, ethical approval and patient consent were not required. This statement is consistent with the journal’s editorial policies.

Search strategy

In this systematic review and meta-analysis, we searched PubMed, Embase, and Web of Science up to August 2025, with no start date and language restrictions. Searches included the following MeSH descriptors: ‘abdominal pain’, ‘chronic pain’, ‘pelvic pain’, ‘laparotomy’, ‘laparoscopy’, ‘abdomen/surgery’, ‘tissue adhesions’. The search strategy for each database is provided in the Appendix (Table S1). We manually checked the reference lists of relevant articles to identify additional potentially relevant papers.

Inclusion and exclusion criteria

We included cohorts or RCTs of studies that (1) patients with chronic pain due to postoperative adhesions (pain duration ≥ 3 months).; (2) were treated with laparoscopic adhesiolysis surgery; (3) reported outcomes of pain improvement or outcomes of complications; (4) diagnostic laparoscopy alone or no intervention (for RCTs).

We excluded studies: (1) where adhesions were not the primary suspected cause of pain (patients with pain due to endometriosis or inflammatory disease); (2) that had data that overlapped with other studies; (3) that were abstracts, letters or reviews.

The definition of ‘pain improvement’ was not standardized across the included studies. The definition of “pain improvement” was not standardized across the included studies. We accepted the outcomes as defined by the original authors. The specific measurement tools and criteria varied considerably, including, for example, a ≥ 50% reduction in visual analog scale (VAS) or numerical rating scale (NRS) scores (e.g., Swank et al., 2003), patient-reported global impression of “improvement” (e.g., Cheong et al., 2014), or a substantial reduction in analgesic use. This heterogeneity in outcome assessment is a recognized limitation. For the purpose of the meta-analysis, These heterogeneous definitions were harmonized into binary outcomes (improved vs. not improved) for statistical pooling; however, such harmonization does not imply clinical equivalence across studies and may introduce interpretive imprecision.

Data extraction

Two reviewers (MDW and YG) independently extracted and checked the data. For relevant articles, we extracted information on study design, including the first author’s name, year of publication, title, study country, study type, use of non-invasive techniques for diagnosis of adhesions, use of adhesion barriers, characteristics, number of participants and outcomes reported. When outcome measures were registered during several time intervals within the same study, we used the data from the longest follow-up period.

Quality assessment

We assessed the quality of all studies using the revised Joanna Briggs Institute Critical Appraisal Tools of eight items. The tool categorizes assessment results into four levels: “Yes”, “No”, “Unclear” and “Not Applicable”. Among them, “Yes” represents one point, and the other options are not scored. The total score is out of eight points. The risk of bias was then categorized into three levels based on the score: low risk (six to eight points), medium risk (three to five points), and high risk (zero to two points).

The methodological quality of the studies was independently assessed by two investigators (MDW and YG). Additionally, a third investigator (GZZ) independently reviewed these assessments. In cases of any disagreements, a consensus was reached through discussion and agreement among the investigators.

Statistical analysis

Pooled estimates of pain improvement rates with corresponding 95% confidence intervals (CIs) were computed using a random-effects model. I2 statistic was used to assess heterogeneity of included studies, with I2 > 50% suggesting significant heterogeneity [17]. Prespecified subgroup analyses were conducted to explore potential sources of heterogeneity, stratified by the use of adhesion barriers, follow-up duration (mid-term ≤ 12 months vs. long-term > 12 months), surgical specialty (gynecology vs. general surgery), geographical region, and primary adhesion site (abdominal vs. pelvic). Sensitivity analyses were performed by sequentially excluding individual studies to evaluate the robustness of the pooled results. Univariate meta-regression was applied to assess the statistical significance of subgroup differences.

“Acsine” test was set as a parameter in publication bias detection. All p-values were two sided. A p-value < 0.05 was considered statistically significant. This meta-analysis was conducted using the “meta” package in R statistical software version 4.2.

Results

Study selection and characteristics

A total of 30 studies were included, with 1,450 patients (Fig. 1). The main characteristics of the included studies are summarized in Table 1. Most studies were observational in design, predominantly involved female patients.

Fig. 1.

PRISMA flowchart demonstrating the selection of publications identified in the systematic review and meta-analysis. PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-analyses

Table 1.

Characteristics of included studies

Study	Country	Patients	Location of adhesions	Surgical history✝	Diagnostic work-up	Intervention	Follow-up	Outcome measures
Laparoscopic adhesiolysis with anti-adhesion barrier
Steege and Stout 1991 [5]	USA	30 patients (gynaecology) 100% female	Pelvic	100% gynaecology	Diagnostic laparoscopy	Carbon dioxide laser, blunt anatomical dissolution and adhesion placement interceed	6 − 12 months	Improvement of pain
Nezhat et al. 2000 [18]	Not reported	48 patients (gynaecology) 100% female	Pelvic	Mixed, majority gynecological	History taking, physklical examination, diagnostic laparoscopy	Carbon dioxide laser cracking, place Interced TC7 and rinse with lactated Ringer’s solution	2 − 8 weeks, 6 − 12 months and 2 − 5 years	Improvement of pain Complications Relapse
Khaitan et al. 2003 [19]	USA	19 patients (general surgery) 89.47% female	Abdominal and pelvic	15.79% gynaecology 5.26% general surgery 78.95% mixed	History taking, physical examination, diagnostic laparoscopy	Lysis and placement of hyaluronic acid-carboxy methylcellulose membrane	9.6 months (range 1 − 32)	Improvement of pain Complications Using painkillers
Swank et al. 2003 [20]	Netherlands	200 patients(general surgery) 74% female	Abdominal	37.5% gynaecology 62.5% general surgery	History taking, physical examination, Diagnostic laparoscopy, ultrasound, radiography, colonoscopy	Argon laser, ultrasonic knife lysed, Seprafilm placed	3 months	Improvement of pain Complications
Neagoe et al. 2018 [21]	Romania	20 patients (general surgery) 65% female	Abdominal	Not reported	History taking, physical examination, diagnostic laparoscopy	Open surgery, 50 ml methylene blue (1%)50 mL	28.5 months	Pain scores
Joergensen and Settnes 2019 [22]	Denmark	3 patients (gynaecology) 100% female	Pelvic	66.67% gynaecology 33.33% mixed	History taking, physical examination, diagnostic laparoscopy, ultrasound	Sharp dissection of adhesions, Placing anti adhesion adhesive	3 − 12 weeks	Improvement of pain
Cheong et al. 2014 [12]	UK	50 patients (gynaecology) 100% female	Pelvic	Not reported	History taking, physical examination, diagnostic laparoscopy	RCT: adhesiolysis vs. diagnostic laparoscopy, Icodextrin 4% solution	0, 3 and 6 months	Improvement of pain QOL (SF-12 EHP-30) Complications
van den Beukel et al. 2023 [23]	Netherlands	122 patients (general surgery) 76.23% female	Abdominal	Not reported	History taking, physical examination, diagnostic laparoscopy, CineMRI non-invasive diagnosis	Icodextrin 4% solution, hyaluronic acid-carboxy methylcellulose membrane	70 months	Relapse Consult a surgeon
Laparoscopic adhesiolysis without anti-adhesion barrier
Arndt and Creutzfeldt 1976 [24]	Germany	7 patients (general surgery) 100% female	Abdominal	71.43% general surgery 28.57% mixed	History taking, physical examination, diagnostic laparoscopy	Sharp dissection of adhesions	6 − 18 months	Improvement of pain
Goldstein et al. 1979 [25]	USA	26 patients (gynaecology) 100% female	Pelvic	26.92% gynaecology 65.38% general surgery	History taking, physical examination, diagnostic laparoscopy	Lysis with scissors and fixation of uterus	1 − 51 months	Improvement of pain Negative laparoscopies
Kleinhaus 1984 [26]	USA	2 patients (general surgery) 100% female	Abdominal	50% general surgery 50% mixed	Diagnostic laparoscopy	Lysis of adhesions	6 and 12 months	Improvement of pain
Sutton and MacDonald 1990 [27]	UK	65 patients (gynaecology) 100% female	Abdominal	55.38% gynaecology 23.08% general surgery 10.77% mixed	Diagnostic laparoscopy	CO2 laser relaxation	1 − 5 years	Improvement of pain Negative laparoscopies
Tschudi et al. 1993 [28]	Not reported	19 patients (general surgery) unclear	Not reported	Not reported	Diagnostic laparoscopy	Not reported	18.3 months (range 5 − 36)	Improvement of pain
Fayez and Clark 1994 [29]	USA	156 patients (gynaecology) 100% female	Abdominal and pelvic	Majority is gynaecology	History taking, physical examination, imaging on indication, diagnostic laparoscopy	Laser relaxation, Lactic acid Ringer’s solution rinse	12 years	Improvement of pain Return to daily activity Complications Relapse
Freys et al. 1994 [30]	Germany	58 patients (general surgery) 68.97% female	Abdominal	15 appendicitis, 4 single major surgeries, 39 multiple major surgeries	History taking, physical examination, diagnostic laparoscopy, Ultrasound, NMR, CT, gas sleeve tube (GIT) intracavity endoscopic examination	Sharp dissection of adhesions	2.5 years	Improvement of pain Complications
Mueller et al. 1995 [31]	Switzerland	51 patients (gynaecology) 76.47% female	Abdominal	35.29% gynaecology 64.71% general surgery	History taking, physical examination, diagnostic laparoscopy, Ultrasound, abdominal X-ray, colonoscopy, contrast imaging, CT	Sharp dissection of adhesions	6 − 36 months	Improvement of pain
Hallfedt et al. 1995 [32]	Not reported	16 patients (general surgery) 93.75% female	Abdominal	12.5% gynaecology 62.5% general surgery 12.5% mixed	History taking, physical examination and imaging on indication, diagnostic laparoscopy	Scissors with diathermia	9 months (range 4 − 18)	Improvement of pain Recommendation Complications
Chen et al. 1997 [33]	China	10 patients (general surgery) 100%female	Pelvic	100% gynaecology	Diagnostic laparoscopy	Electrocauterization dissolution	3 months	Improvement of pain
Bremers et al. 2000 [34]	Netherlands	12 patients (general surgery) 91.67% female	Abdominal	Not reported	History taking, physical examination, diagnostic laparoscopy	Sharp or diathermic dissection	3, 6 and 12 months	Improvement of pain QOL (GIQLI MOS-SF36) Complications Negative laparoscopies
Malik et al. 2000 [35]	Germany	101 patients(gynaecology) 100% female	Pelvic	89.11% have a history of surgery	Diagnostic laparoscopy	Electrocauterization dissolution, Lactic acid Ringer’s solution rinse	6 − 18 months	Improvement of pain Return to daily activity
Schenk et al. 2000 [36]	Not reported	56 patients (general surgery) 66.07% female	Abdominal	46.43% gynaecology 51.79% general surgery 1.79% mixed	History taking, physical examination, diagnostic laparoscopy	Sharp tools are lysed, washed with heated lactic acid Ringer’s solution	31.5 month	Improvement of pain Relapse
Shayani et al. 2002 [37]	Not reported	18 patients (general surgery) 94.44% female	Abdominal and pelvic	Majority is general surgery	History taking, CT angiography, colonoscopy	Not reported	11 months	Improvement of pain Relapse Using painkillers
Dunker et al. 2004 [38]	Netherlands	23 patients (general surgery) 95.65% female	Abdominal	21.74% gynaecology 4.35% general surgery 73.91% mixed	History taking, physical examination, diagnostic laparoscopy	Not reported	3, 6, 12, 24 months with second-look laparoscopy	Improvement of pain QOL (GIQLI MOS-SF36) Complications Relapse
McClain et al. 2011 [39]	USA	31 patients(general surgery) 93.55% female	Abdominal and pelvic	100% have undergone surgery	History taking, physical examination, diagnostic laparoscopy	Sharp dissection of adhesions	3, 6, 9 and 12 months	Pain scores Complications
Paajanen, Paavo et al. 2018 [40]	Finland	68 patients (general surgery) 86.76% female	Abdominal	Majority is mixed	History taking, physical examination, diagnostic laparoscopy	Sharp dissection of adhesions	3.6 years	Improvement of pain
Hardy and Rousseau 2019 [41]	Canada	10 patients (gynaecology) 100% female	Pelvic	100% gynaecology	History taking, physical examination, diagnostic laparoscopy	Loose adhesion, hysterectomy	5 years	Improvement of pain
Steege 1994 [42]	USA	8 patients (gynaecology) 100% female	Pelvic	75% gynaecology	History taking, physical examination, diagnostic laparoscopy	4 × Lysis using laser through Tecnkhoff catheter Ringer’s Lactate	7 − 11 months	Improvement of pain
Peters et al. 1992 [43]	Netherlands	48 patients (gynaecology) 100% female	Abdominal and pelvic	54.17% previous laparotomies	Diagnostic laparoscopy	RCT: Sharp dissection of adhesions vs. diagnostic laparoscopy	9 − 12 months	Improvement of pain QOL (GIQLI MOS-SF36) Return to daily activity

RCT randomized control trial, GIQLI Gastro-intestinal Quality of Life Index, QOL Quality of Life

^✝Summary of surgical history includes: type of previous interventions i.e. percentage of patients with history of gynaecology or general surgery, or mixed (both gynaecology and general) surgery

Four RCTs were included, one with an adhesion barrier and the rest without an adhesion barrier. In all studies, the vast majority of adhesions were adhesiolysis through laparoscopy. Adhesion barriers were used in eight studies. Alternative adhesion-reduction techniques were implemented in seven of the 22 studies that did not use adhesion barriers. These other techniques included the use of uterine prolapse suspension in one study and the use of lactated Ringe’s solution irrigation in four studies. In one study, the uterus was removed, and in another, a Tenckhoff catheter was placed in the laxity for intermittent outpatient laparoscopy and irrigated with lactated Ringer’s solution (Table 1).

Pre-treatment diagnosis is based primarily on a history of prior surgery followed by physical examination and occasionally imaging studies to rule out other diagnoses. One study used noninvasive diagnostic techniques to diagnose adhesions, such as cine-MRI, a technique that utilizes magnetic resonance imaging to diagnose adhesions by taking consecutive moving images of the abdominal organs (Table 1).

In 14 papers, all patients included were female, with a greater proportion of females in studies with mixed populations, with all females accounting for more than 60%. The majority of pain and adhesion sites were abdominal, and some studies had a mix of abdominal and pelvic patients. In addition, in the gynecologic and general surgical studies, most patients had a mixed history of gynecologic and general surgical procedures (Table 1).

A review of the RCTs conducted revealed that the majority of studies exhibited a low risk of bias, with the exception of one study. Of the studies included, two were deemed to be at high risk, 12 at moderate risk, and 16 at low risk (Results for the risk of bias assessment are presented in Supplementary Table S2). Common methodological limitations included unclear blinding and incomplete follow-up.

Assessment of the effectiveness of adhesiolysis

A total of 27 studies with 1,150 participants were eligible for calculation of pain improvement rates, and the pooled rate was 67.3% (95% CI: 57.7 − 76.2%, I² = 91% (Fig. 2). The pain improvement rate of the group with adhesion barrier was 54.5%, while the pain improvement rate of the group without adhesion barrier was 70.5%, with no statistical difference between the two groups (P = 0.16).

Fig. 2.

Forest plot of pain improvement in patients undergoing laparoscopic adhesiolysis

Of the six studies of adhesiolysis with adhesion barriers, two studies reported pain improvement at long-term follow-up and four studies reported pain improvement at mid-term follow-up. The rate of pain improvement at any follow-up was 54.5% (95% CI: 34.3−74.0%, I² = 81%) in 326 patients, with a pooled incidence of long-term improvement of 49.8% (95% CI: 25.4−74.3%, I² = 80%) in 78 patients; and a pooled incidence of interim improvement of 61.3% (95% CI: 25.3−91.3%, I² = 85%) in 248 patients. Although pooled pain improvement rates were numerically higher at mid-term follow-up than at long-term follow-up, the difference was not statistically significant (Supplementary Figure S6, Table 2).

Table 2.

Main outcomes measures, for total calculation and subgroups

	All studies					With adhesion barrier					Without adhesion barrier
	Studies (n)	Participants (n)	Rate (%)	I2 (%)	*P-val	Studies (n)	Participants (n)	Rate (%)	I2 (%)	*P-val	Studies (n)	Participants (n)	Rate (%)	I2 (%)	*P-val
All studies	27	1150	67.3 (57.7 − 76.2)	91		6	326	54.5 (34.3 − 74.0)	81		21	824	70.5 (60.3 − 79.9)	89
Follow-up time
Long-term	20	868	66.9 (56.0 − 76.9)	90	0.8836	2	78	49.8 (25.4 − 74.3)	80	0.7254	18	790	68.8 (57.2 − 79.3)	90	0.3387
Intermediate	7	282	69.5 (46.8 − 88.2)	87	Ref	4	248	61.3 (25.3 − 91.3)	85	Ref	3	34	83 (68.7 − 93.5)	0	Ref
Department
gynaecology	12	548	67.9 (51.5 − 82.4)	91	0.0148	4	107	57.7(24.5 − 87.5)	81	0.9474	8	441	72.8 (54.5 − 87.7)	92	0.7600
general surgery	15	602	67.0 (54.8 − 78.2)	90	Ref	2	219	54.7 (20.7 − 86.3)	89	Ref	13	383	69.2 (56.0 − 80.9)	86	Ref
Year of publication
2000 − 2023	14	678	61.7 (45.7 − 76.6)	91	0.1488	5	296	54.3(28.2 − 79.2)	80	0.7764	9	382	65.4 (45.2 − 83.1)	96	0.3216
1976 − 1999	13	472	73.4 (64.2 − 81.7)	75	Ref	1	30	63.3(43.9 − 80.1)	−	Ref	12	442	74.4 (64.5 − 83.1)	76	Ref
Area
North America	7	251	82.7 (66.3 − 94.4)	78	0.6028	2	49	67.5(53.8 − 79.7)	0	0.6520	5	202	89 (68.3 − 99.4)	78	0.4216
Unknown	5	157	67.7 (49.4 − 83.6)	82	0.9429	1	48	37.5(24.0 − 52.6)	−	0.6389	4	109	74.7 (66.1 − 82.4)	3	0.8238
Europe	14	732	59.1 (45.3 − 72.1)	92	0.6829	3	229	59.4(10.6 − 98.0)	81	Ref	11	503	60.8 (46.4 − 74.3)	91	0.7226
Asia	1	10	70.0 (34.8 − 93.3)	−	Ref	−	−	−	−		1	10	70.0 (34.8 − 93.3)	−	Ref
Proportion of Females
Equal to 100%	14	516	71.9 (56.4 − 85.1)	90	0.4495	4	107	57.7 (24.5 − 87.5)	81	0.9474	10	409	77.2 (61.1 − 90.0)	89	0.2787
Unknown	1	19	63.2 (38.4 − 83.7)	−	0.9841	−	−	−	−		1	19	63.2 (38.4 − 83.7)	−	0.9288
Less than 100%	12	615	63.6 (50.2 − 76.1)	92	Ref	2	219	54.7 (20.7 − 86.3)	89	Ref	10	396	65.5 (50.6 − 79.0)	89	Ref
Adhesive site
Pelvic	9	238	68.4 (47.4–86.1)	82	0.8364	3	59	68.0 (19.5 − 99.2)	85	0.3280	6	179	70.0 (45.0 − 89.9)	84	0.9327
Abdominal and pelvic	3	193	83.1 (72.9 − 91.3)	36	0.2929	1	19	73.7 (48.8 − 90.9)	−	0.3049	2	174	86.4 (79.1 − 92.3)	14	0.4190
Unknown	2	31	61.3 (43.8 − 77.4)	−	0.8403	−	−	−	−	−	2	31	61.3 (43.8 − 77.4)	0	0.6351
Abdominal	13	688	65.0 (50.5 − 78.3)	93	Ref	2	248	37.9 (32.0 − 44.0)	0	Ref	11	440	70.3 (55.1 − 83.5)	89	Ref
Anti-adhesion barrier
liquid	1	26	30.8 (14.3 − 51.8)	−	0.4101	1	26	30.8 (14.3 − 51.8)	−	0.3130	−	−	−	−
Gel	1	3	100. 0 (29.2 − 100.0)	−	*0.0445	1	3	100.0 (29.2 − 100.0)	−	*0.0246	−	−	−	−
Unknown	21	824	70.5 (60.3 − 79.9)	89	0.1401	−	−	−	−	−	−	−	−	−
Absorbable film agent	4	297	51.4 (34.0 − 68.7)	80	Ref	4	297	51.4 (34.0 − 68.7)	80	Ref	−	−	−	−

Rate: rate of pain improvement

Of the 21 studies of adhesiolysis without adhesion barriers, 18 studies reported pain improvement at long-term follow-up and three studies reported pain improvement at mid-term follow-up. The rate of pain improvement at any follow-up was 70.5% (95% CI: 60.3 − 79.9%, I² = 89%) in 824 patients, the pooled incidence of long-term improvement was 68.8% (95% CI: 57.2 − 79.3%, I² = 90%) in 790 patients, and the pooled incidence of mid-term improvement was 83% (95% CI: 68.7 − 93.5%, I² = 0%) in 34 patients, and the rate of pain improvement at mid-term follow-up was higher than the rate of pain improvement at long-term follow-up, but the difference was not significant (Supplementary Figure S7, Table 2). In all studies, the pain improvement rate during mid-term follow-up was higher than that during long-term follow-up (69.5% [95% CI: 46.8 − 88.2%, I² = 87%] vs. 66.9% [95% CI: 56.0 − 76.9%, I² = 90%]), but the difference was not significant (Supplementary Figure S5, Table 2).

In the subgroup analysis of factors influencing pain relief, we initially categorized patients according to whether they utilized an adhesion barrier following adhesiolysis surgery. Thereafter, we proceeded to examine these two subgroups in more granular subgroups based on a multitude of factors that may influence the efficacy of pain relief. Subgroup analyses showed that the pain improvement rates between subgroups in the without adhesion barriers group were all higher than the pain improvement rates between subgroups with adhesion barriers (Supplementary Figure S8−Figure S22, Table 2). In particular, the pain improvement rate in the abdominal group of the adhesion site subgroup of the without adhesion barrier group was 70.3% (95% CI: 55.1−83.5%, I² = 89%) (Supplementary Figure S22, Table 2), which was numerically higher than the rate reported in the group with adhesion barriers, which was 37.9% (95% CI: 32.0−44.0%, I² = 0%) (Supplementary Figure S21, Table 2).

Assessment of adhesiolysis safety

A total of 13 studies with 739 participants were eligible for calculation of postoperative complications rates, and the pooled rate was 5.2% (95% CI: 1.9−10.1%, I² = 80%). And one study reported no mortality. The incidence of postoperative complications was 7.8% (95% CI: 0.7−21.5%, I² = 83%) in the four studies with an adhesion barrier, and the combined rate in the nine studies without an adhesion barrier was 4.2% (95% CI: 1.0−9.6%, I² = 79%),two groups have no statistical significance (P = 0.51) (Supplementary Figure S1).

Assessment of the efficacy and safety of adhesiolysis in RCTs

Four RCTs were conducted to compare the outcomes between adhesiolysis (adhesiolysis group, n = 144) and diagnostic laparoscopy (control group, n = 127). Pain improvement was reported by 38.9% of patients in the adhesiolysis group and 36.2% of patients in the control group, with no statistically significant difference between the two groups (RR = 1.05; 95% CI: 0.61−1.83, I² = 60%, P = 0.28). In a RCT using an adhesion barrier, the rate of pain improvement in the adhesiolysis group was slightly higher at 30.8% than in the control group at 16.7%, but the difference was not significant (RR = 1.85; 95% CI: 0.64−5.35, I² = NA). In three other RCTs without an adhesion barrier, the rate of pain improvement was 40.7% in the adhesiolysis group and 40.8% in the control group. There was no difference in pain improvement rates between the two groups (RR = 0.94; 95% CI: 0.49−1.79, I² = 70%) (Figures 2 and 3).

Fig. 3.

Forest plot of relative risk of pain improvement with laparoscopic adhesiolysis vs. diagnostic laparoscopy in RCTs

Three randomized controlled trials were eligible for analysis of postoperative complications. When pooled as incidence estimates within the adhesiolysis groups, the overall postoperative complication rate was 4.2% (95% CI: 0.0–14.4%; I² = 73%). Two trials without adhesion barriers reported a pooled complication rate of 8.5% (95% CI: 3.7–14.9%; I² = 0%), whereas one trial using an adhesion barrier reported no postoperative complications.

In contrast, comparative analysis between the adhesiolysis group and the diagnostic laparoscopy control group showed no statistically significant difference in postoperative morbidity. Complications occurred in 6.7% of patients in the adhesiolysis group and in 0% of controls, yielding a pooled relative risk of 4.66 (95% CI: 0.76–28.52; I² = 0%; P = 0.36). No perioperative mortality was reported in any randomized trial.

Sensitivity analysis and publication bias

We conducted a sensitivity analysis by sequentially excluding each study to evaluate the robustness of the pooled pain improvement rate. The results showed that after excluding any single study, the overall pain improvement rate no significant deviation compared to the original pooled rate, indicating good robustness of the results (Supplementary Figure S24). The sensitivity analysis results further support the reliability of the meta-analysis conclusions. The funnel plot was symmetrically for the meta-analysis of the pain improvement rate of patients who underwent adhesiolysis surgery (Supplementary Figure S2). The “Arcsine” test showed a pain improvement rate of p = 0.333, indicating no evidence of publication bias.

Discussion

This updated meta-analysis, incorporating 30 studies and 1,450 patients, represents the most comprehensive synthesis to date evaluating laparoscopic adhesiolysis for adhesion-related chronic abdominal and pelvic pain. Three principal findings emerge, all of which require cautious interpretation in light of study design and methodological limitations. Although single-arm and other non-randomised studies reported a pooled pain improvement rate of 67.3% (95% CI: 57.5–76.2%), randomised controlled trials demonstrated no significant difference between adhesiolysis and diagnostic laparoscopy alone (38.9% vs. 36.2%; RR = 1.05, 95% CI: 0.61–1.83). This discrepancy highlights the critical influence of study design on outcome interpretation. Higher improvement rates observed in non-randomised studies are likely influenced by selection bias, placebo effects inherent to surgical interventions, and regression to the mean in chronic pain conditions characterised by symptom fluctuation. Accordingly, these observational findings should be regarded as hypothesis-generating rather than evidence of causal effectiveness.

Our findings align with yet refine previous systematic reviews. Van den Beukel et al. reported a similar improvement rate of 72.0% but with wider confidence intervals (95% CI: 61.0–83.0%) based on only 13 studies [14]. Our expanded sample (n = 30 studies) provides more precise estimates (95% CI: 57.5–76.2%) and enhances the reliability of the pooled results. Whereas non-randomized studies report relatively high rates of pain improvement, all available randomized trials consistently demonstrate no significant advantage of adhesiolysis over diagnostic laparoscopy alone [44, 45].

A counterintuitive observation was that studies reporting the use of adhesion barriers demonstrated lower pain improvement rates (54.5%) compared with studies without barrier use (70.5%). This finding must not be interpreted as evidence that adhesion barriers worsen outcomes. Confounding by indication is highly probable, as barriers are typically applied in patients with more extensive, dense, or vascularized adhesions, who may inherently have a poorer pain prognosis. Confounding by indication is likely, as barriers may have been preferentially used in patients with more extensive or complex adhesions who inherently have a poorer pain prognosis. In addition, substantial clinical heterogeneity exists with respect to barrier materials and application techniques, and the limited number of studies and patients reporting barrier use precludes meaningful stratified analyses. These results are therefore best considered exploratory and hypothesis-generating.​

The pooled complication rate of 4.7% (95% CI: 1.4–9.8%), with no reported perioperative mortality, suggests an acceptable short-term safety profile. However, major evidence gaps remain. Data on re-adhesion rates, long-term adverse outcomes, and negative laparoscopy rates were largely absent, substantially limiting comprehensive safety assessment. The formation of new adhesions following adhesiolysis remains a particular concern, as it may offset initial symptom relief and lead to more complex subsequent management. Standardised reporting of both short- and long-term safety outcomes is therefore essential in future studies.

Substantial statistical heterogeneity was observed across included studies (I² = 91%). Despite prespecified subgroup analyses and univariable meta-regression, this heterogeneity could not be adequately explained. A major contributor is the wide variability in the definition of “pain improvement,” which was frequently based on non-standardised or author-defined criteria rather than validated pain assessment tools [44]. Because heterogeneous and often non-standardized definitions were dichotomized for analysis, pooled improvement rates should not be interpreted as uniform clinical benefit. Rather, they represent aggregated reporting patterns across studies with varying outcome constructs.

Within the current evidence base, laparoscopic adhesiolysis should not be regarded as a first-line intervention for most patients with adhesion-related chronic pain. Nevertheless, in carefully selected individuals—particularly those with dense, vascularized adhesions involving bowel structures and evaluated within a multidisciplinary framework—the procedure may still be considered. Clinical decision-making should integrate adhesion characteristics, symptom severity, prior treatment response, psychosocial context, and surgical expertise [46]. Furthermore, given the fluctuating course of chronic pain and the well-recognized placebo response associated with surgical interventions, thorough patient counseling and a structured shared decision-making process are essential components of optimal care.

Surgical technique and tissue handling may influence both adhesion formation and long-term pain outcomes. Factors such as suture strategy, access platform, and minimally invasive optimization may affect postoperative healing and adhesion burden. Recent analyses in minimally invasive gynecologic surgery have demonstrated that refined vaginal cuff closure strategies and optimized access platforms may influence postoperative recovery and complication profiles [47, 48]. Although these studies focus primarily on prevention rather than ment of established adhesions, they highlight the broader importance of surgical quality and technique in adhesion-related outcomes.

Taken together, this meta-analysis provides a comprehensive descriptive synthesis of the existing literature but does not establish causal evidence for the effectiveness of laparoscopic adhesiolysis in adhesion-related chronic pain. Well-designed, adequately powered randomised trials with standardised pain outcomes and long-term follow-up are required to better define the role of adhesiolysis within multidisciplinary management strategies for chronic abdominal and pelvic pain.

Conclusion

In conclusion, laparoscopic adhesiolysis should not be considered a first-line intervention for most patients with adhesion-related chronic pain. However, in carefully selected cases and within a shared decision-making framework, it may still have a role. Current randomized evidence does not support its superiority over diagnostic laparoscopy alone.

Abbreviations

RCT

Randomized Controlled Trial

CI

Confidence Interval

PRISMA

Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Authors’ contributions

YHY, GZZ, XG and MDW initiated the project and were responsible for the design of the protocol. MDW, XC and YG did the literature review, collected the data, and assessed the quality of the studies. MDW, YG, XG and SQL analysed the data. MDW, YG, RZ, XG and XSC interpreted the data. MDW and YG wrote the initial draft of the manuscript. XRL, YLZ, MXH, XG and ZMX were responsible for critical revision of the manuscript and provided important intellectual content. All authors approved the final version of the manuscript submitted for publication.

Funding

This work was supported by Medical Joint Special Project of Kunming University of Science and Technology (grant NO. ZZ2023YX126A).

Data availability

A summary of the data is presented in Table 1 of this article. The full dataset extracted from the included studies is available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

Not applicable.

Competing interests

The authors declare no competing interests.