Endometriosis is a benign and chronic disease characterized by inflammation of the endometrial tissue outside the uterus. Numerous physical therapy interventions have been studied to alleviate the related symptoms.
ObjectiveTo evaluate the effectiveness of different physical therapy methods and techniques in improving the symptoms triggered by endometriosis.
MethodsSystematic review of articles exclusively including women with endometriosis, quantitative studies, and interventions that included some form of physical therapy techniques. Difference in mean differences and their 95% confidence interval were calculated. The I² statistic was used to determine the degree of heterogeneity, and the GRADE approach was used to assess the certainty of the evidence.
ResultsThe interventions analyzed included manual therapy, education, electrotherapy, exercise, relaxation techniques, and acupuncture. Dyspareunia (p = 0.001; I2 = 95.6%) and pelvic pain (p = 0.012; I2 = 90.1%) were significantly reduced. Quality of life was significantly increased (p < 0.001; I2 = 94.9%). The certainty of the evidence obtained was moderate.
ConclusionMassage therapy combined with perineal stretching, electrotherapy, acupuncture, exercise, and patient education are effective in improving chronic pelvic pain, dyspareunia, dysmenorrhea, non-menstrual pain, the basic and modular domains of quality of life, mental and physical health, and functional well-being in endometriosis. Healthcare professionals must recognize the importance of evaluating each case individually and tailoring treatments to the specific needs of each patient.
Endometriosis is a benign, chronic, and common gynecological disease characterized by inflammation of endometrial tissue outside the uterus, particularly in the pelvis.1 These lesions form when endometrial tissue ascends through the fallopian tubes and implants on the peritoneal surface or pelvic organs.2,3 Its prevalence is around 10%, being higher among women of reproductive age, and up to 70% of cases are symptomatic.4
The main symptom is pain, which can manifest in various forms, such as dysmenorrhea, dyspareunia, chronic pelvic pain, dysuria, and dyschezia.4,5 Additionally, endometriosis is associated with psychological issues that further diminish quality of life.3,6
The primary treatment for endometriosis involves the surgical removal of ectopic tissue and/or hormonal therapy to reduce symptoms of pain and inflammation. These treatments halt ovulation and the natural hormonal cycle, reducing endometrial tissue by inducing cell death or preventing its growth.3
Physical therapy is a safe and effective complementary treatment for endometriosis.7 Although specific protocols have not yet been established, an integrated approach combining manual therapy, therapeutic exercise, physical modalities, and patient education is recommended.7,8
Therefore, the aim of this study was to evaluate the effectiveness of different physical therapy interventions in improving the symptoms caused by endometriosis.
MethodsData sources and searchesThis systematic review and meta-analysis were prospectively registered on PROSPERO (ID: CRD42023432838) and followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA),9 the recommendations for their implementation in Exercise, Rehabilitation, Sport Medicine and Sports Science (PERSiST)10 and the reporting guidelines and the recommendations from the Cochrane Collaboration.11 The PICOS question was then chosen as follows: P – Population: women with endometriosis; I – Intervention: physical therapy methods or techniques; C – Control: no intervention, pharmacological treatment, placebo, routine care, or self-applied treatments; O – Outcome: pain intensity and frequency and/or quality of life; S – Study designs: quantitative studies.
A systematic search of publications was conducted in July 2023 in the databases: Scopus, WOS, PubMed, CINAHL and MEDLINE. The search strategy is presented in Supplementary Material 1.
Study selectionAfter removing duplicates, two reviewers independently screened the articles, with a third reviewer resolving any disagreements. The inclusion criteria were as follows: (i) the sample consisted of women diagnosed with endometriosis; (ii) at least one sample group received treatment with physical therapy techniques; (iii) the control group received no intervention, pharmacological treatment, placebo, routine care, or self-administered treatments; (iv) studies assessed outcomes related to quality of life and/or pain intensity and frequency; and (v) the study design was quantitative. No exclusion criteria were defined.
Data extraction and quality assessmentTwo reviewers used a customized data extraction table in Microsoft Excel. The extracted data included demographic information, sample characteristics, study-specific details, treatment parameters, follow-up duration, dropout rates, and study outcomes.
Assessment of risk of biasThe methodological quality of the studies was assessed using the PEDro scale.12 The Risk of Bias 2 (RoB 2) tool was used to assess the risk of bias in randomized clinical trials13 and the ROBINS-I tool was used for non-randomized studies.14 The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was employed to evaluate the quality of the evidence.15 Two reviewers independently conducted the assessments, with a third reviewer resolving any disagreements.
Data synthesis and analysisStandardized mean differences (SMDs) and their 95% confidence intervals (CIs) were calculated as the between-group difference in means divided by the pooled standard deviation (SD), using Hedges’ g corrected effect sizes.16,17 When these data were not available in the study, they were requested from the authors via email. Hedges’ g was interpreted as follows: 0–0.2 (very small), 0.2–0.5 (small), 0.5–0.8 (moderate), and >0.8 (large).18 Heterogeneity was assessed using the I² statistic, with values greater than 50% considered indicative of substantial heterogeneity.19 Given the considerable heterogeneity among studies, a random-effects model was used. Analyses were performed using Comprehensive Meta-Analysis (CMA) V2 software (Biostat, NJ).
ResultsCharacteristics of the selected studiesAfter searching the databases, a total of 1154 results were obtained. Of these, 101 were duplicates, and 1042 were excluded based on the selection criteria, leaving 11 articles for inclusion. The Kappa coefficient between reviewers was 0.97, indicating a high level of agreement. The PRISMA flow diagram is presented in Supplementary Material 2.
Characteristics of selected studiesTen experimental studies20–29 were included, of which eight were randomized controlled trials,20,21,23–27,29 and two were quasi-experimental studies.22 Additionally, one retrospective observational case-control study was included.30 Eight of the studies achieved good methodological quality20,21,23–27,29 on the PEDro scale (Supplementary Material 3).
Interventions analyzedThe interventions analyzed included manual therapy,20,22,28,29 education,20,22,27,29 electrotherapy,24,26,28,30 exercise,23,28,29 relaxation techniques,23,27,28 and acupuncture.21,25 In three studies, these methods were combined with psychological intervention21,28 or pharmacological treatment27 (Table 1).
Methodological characteristics of the studies analyzed.
| Authors | Study design | Sample size | Intervention | Duration of intervention | Number of sessions (duration of sessions) | |
|---|---|---|---|---|---|---|
| Experimental group | Control group | |||||
| Bi et al.30 (2018) | RCCS | 154 | Neuromuscular electrical stimulation | None | 10 weeks | 30 (30 min) |
| Del Forno et al.22 (2020) | QES | 10 | Education + Thiele's massage with perineal stretching | — | 11 weeks | 5 (30 min) |
| Del Forno et al.20 (2021) | RCT | 30 | Education + Thiele's massage with perineal stretching | None | 11 weeks | 5 (30 min) |
| Farshi et al.29 (2020) | RCT | 73 | Manual therapy + therapeutic exercise + self-care counseling (Orem) | Routine care | 7 weeks | 7 (60–90 min) |
| Gonçalves et al.23 (2017) | RCT | 16 | Hatha yoga + acupuncture + psychological intervention | Drugs | 8 weeks | 16 (120 min) |
| Meissner et al.21 (2016) | RCT | 60 | Psychotherapy + somatosensory stimulation | None | 12 weeks | None described (30–60 min) |
| Mira et al.26 (2015) | RCT | 22 | TENS on acupuncture points | Self-applied TENS | 8 weeks | EG: 8 (30 min) CG: 112 (20 min) |
| Mira et al.24 (2020) | RCT | 78 | Self-applied TENS + hormonal treatment with progestogens | Progestogen | 8 weeks | 112 (20 min) |
| de Sousa et al.25 (2016) | RCT | 42 | Acupuncture | Placebo acupuncture | 5 weeks | 5 (40 min) |
| Sebe et al.28 (2012) | QES | 26 | Manual therapy + exercise + TENS + relaxation techniques + psychological intervention | — | 10 weeks | 10 (150 min) |
| Zhao et al.27 (2012) | RCT | 87 | Progressive muscle relaxation + leuprodila | Leuprodila | 12 weeks | 24 (40 min) |
CG: Control group; EG: Experimental group; QES: Quasiexperimental study; RCCS: Retrospective case control study; RCT: Randomized clinical trial; —: not applicable.
Manual therapy consisted of massage, always combined with stretching20,22,29 or lumbar repositioning.28 All studies that included manual therapy20,22,28,29 combined it with other methods: education,20,22,29 exercise,28,29 relaxation techniques,28 electrotherapy,28 and/or psychological intervention.28
The education provided to patients20,22,27,29 included, in two cases, information about the anatomy and function of the perineum.20,22 Similarly, Zhao et al.27 also addressed anxiety and depression during the first session. Finally, the last study that included this method used it as the primary intervention, providing self-care counseling based on Orem's model.29 This model aims to enhance individuals' ability to care for themselves by identifying patient needs, as well as defining tasks and responsibilities for medical care.29 Of the four studies that included education as an intervention method,20,22,27,29 three combined it with manual therapy,20,22,29 one of which also combined it with exercise29; and another combined it with pharmacological treatment.27
The four studies that applied electrotherapy24,26,28,30 did so through neuromuscular electrical stimulation30 or transcutaneous electrical nerve stimulation (TENS).24,26,28 Among these,24,26,28,30 only one combined electrotherapy with manual therapy, exercise, and psychological intervention.28
The interventions that included exercise23,28,29 employed yoga23,29 or combined training.28 The studies that included exercise combined it with relaxation techniques,23,28 manual therapy,28,29 education,29 electrotherapy,28 and/or psychological intervention.28
The relaxation methods applied23,27,28 consisted of meditation aimed at both physical and psychological relaxation23 and the application of Jacobson’s technique.27 These relaxation techniques were evaluated in conjunction with different exercise programs,23,28 education,27 manual therapy,28 electrotherapy,28 drugs,27 and/or psychological interventions.28
Two studies used acupuncture as a treatment method.21,25 One used it as the sole treatment strategy,25 while the other combined it with a psychological intervention.21
Lastly, the non-physical therapy methods included in the interventions were psychology21,28 and pharmacology.27 These treatments involved the intramuscular administration of leuprolide via an 11.25 mg injection27 or psychological interventions, including psychotherapy,21 as well as addressing endometriosis, pain, stress, sexuality, and social relationships.28
Interventions applied to the control groupsThe control group interventions were based on the absence of treatment,20,21,30 pharmacological treatment,23,24,27 placebo,25 routine care,29 or self-administered electrotherapy.26 Pharmacological treatments included standard medication,23 hormonal treatment with progestins,24 and leuprolide.27 In the placebo intervention, acupuncture was performed by placing needles 3 cm away from the original point.25 Routine care aimed to improve disease and mental health outcomes and promote quality of life.29 Self-administered TENS was applied in the S3 – S4 area at a frequency of 85 Hz, a pulse duration of 75 µs, and an intensity of 10, 20, or 30 mA.26
Results in pain intensity and frequencyNine of the studies20–26,28,30 included this variable. The pain-related variables were the intensity of dyspareunia,20–22,24–26,30 (analyzed separately as superficial20,22 or deep20,22,24,26 in some studies) dysmenorrhea,20,24,26,30 chronic pelvic pain,20,21,24–26,30 ovulatory pain,20 non-menstrual pain,30 dysuria,20,24,26 and dyschezia.20,21,24,26,30 Additionally, two studies evaluated the average21,28 and maximum21 intensity of pain (without specifying the type). All these variables were assessed using the Visual Analog Scale,23–26,28 the Numeric Rating Scale,20–22,30 the Subjective Sexual Satisfaction Scale,30 pain diaries where patients recorded all pelvic symptoms,24 and the Deep Dyspareunia Scale.26 In one study, the number of days with pain was also recorded.24
The physical therapy interventions significantly reduced dyspareunia,21,25,30 superficial dyspareunia,20,22 non-menstrual pain,30 chronic pelvic pain,20,21,24–26,30 the maximum intensity of perceived pain,21 and the number of days with pain24 in all cases where these were evaluated. Additionally, these interventions achieved statistically superior results compared to control interventions for reducing dyspareunia,21,25,30 superficial dyspareunia,20 non-menstrual pain,30 chronic pelvic pain,20,21,24–26,30 and the intensity of pain21 in all cases where such comparisons were made.
Ovulatory pain, in the only study where it was evaluated, did not improve with either the physical therapy intervention or the control.20
The average intensity of perceived pain improved significantly with the application of acupuncture and psychology (and it was statistically superior to the control group),21 but not with a multimodal physical therapy treatment combined with psychology.28
Similarly, there was mixed results for deep dyspareunia. It significantly improved with the application of TENS.24,26 This improvement was statistically superior to the control group only when TENS was applied to acupuncture points26 and like the use of medications when self-administered.24 The Thiele massage combined with stretching and education led to significant improvements in one study22 but found no statistical changes in either the experimental or control groups in another study.20
Dysmenorrhea only improved statistically after the application of neuromuscular electrical stimulation (and it was statistically superior to the control group).30 However, it did not improve with Thiele massage combined with stretching and education20 or TENS24,26 (control interventions based on drugs24 and self-administered TENS26 also failed to modify this variable).
Dysuria was significantly reduced with self-administered TENS and it was statistically superior to the control group,24 but did not improve with Thiele massage combined with stretching and education20 or TENS.26
Dyschezia improved with the application of acupuncture and psychology,21 TENS,26 and neuromuscular electrical stimulation30 (all statistically superior to control interventions in these three cases.)21,26,30 However, self-administered TENS also improved this variable but similarly to pharmacological treatment,24 and Thiele massage combined with stretching and education20 did not modify this type of pain.
Finally, one study assessed the long-term effect and found that the significant improvements achieved with acupuncture on chronic pelvic pain and dyspareunia had disappeared, but the intensity of both types of pain was still significantly lower than that reported by the control group.25
Results in quality of lifeNine of the articles analyzed quality of life.21,23–30 Within this variable, both the overall outcome23–26 and the specific results for each of the basic domains23–26 (pain, control and helplessness, emotional well-being, social support, and self-image) and modular domains23–26 (work, relationship with children, sexual relationships, relationship with the doctor, treatment, and infertility) were evaluated. Additionally, two studies assessed the overall scores for the basic and modular domains.24,25 Other studies quantified mental health domains (vitality, social functioning, emotional role, and mental health),21,27–30 physical health domains (physical functioning, role limitations due to physical health, bodily pain, and general health),21,27–30 and functional well-being.21 To do this, they used the SF-36 Health Survey,27–30 the SF-12 Physical and Mental Health Questionnaire,21 the Functional Well-being Form FW-7,21 and the Endometriosis Health Profile (EHP-30).23–26
The physical therapy interventions evaluated significantly improved functional21 and emotional23–26 well-being, social support,23–26 treatment,23–26 and the domains of pain,23–26 control and helplessness,23–26 work,23–26 mental21,27,29,30 and physical health,21,27,29,30 vitality,27,28 and physical function27,28 in all cases where they were assessed. Additionally, the participants in the control group showed significantly less improvement compared to those who received physical treatments in functional21 and emotional23–26 well-being, pain domains,23,25,26 control and helplessness,23,25,26 social support23–26 (except in the study comparing yoga combined with relaxation techniques, which achieved similar results to pharmacological treatments21), work23–25 (except in the intervention comparing TENS application at acupuncture points with self-application, which achieved similar effects26), treatment23,25 (except for pharmacological treatment24 and self-administered TENS,26 which achieved similar effects), mental21,27,29,30 and physical21,27,29,30 health, vitality,27 and physical function.27
In contrast, the self-image domain improved with exercise-based interventions and relaxation techniques,23 self-administered TENS,24 and acupuncture25 (and it was statistically superior to the control interventions). However, it did not improve with TENS application at acupuncture points.26
The relationship with children improved after three of the evaluated interventions (yoga and relaxation techniques, acupuncture, and TENS at acupuncture points),23,25,26 but not with self-administered TENS.24
Sexual relationships improved with yoga and relaxation techniques,23 self-administered TENS,24 and acupuncture,25 but not with TENS at acupuncture points.26 Additionally, among the three interventions that modified this variable, only self-administered TENS24 and acupuncture25 were statistically superior to the control interventions.
The relationship with the doctor improved with the application of yoga and relaxation techniques23 and with TENS at acupuncture points,26 but not with self-administered TENS24 or acupuncture.25 Additionally, only the TENS application was superior to the control intervention.26
Regarding infertility, among the four studies that considered it,23–26 only the treatment including yoga and relaxation techniques achieved significant changes (although similar to the control intervention).23
Social functioning, emotional role, mental health, physical role, bodily pain, and general health improved significantly (and more than the control group)27 with the intervention combining education and relaxation techniques. However, these aspects did not improve with the combined application of manual therapy, exercise, relaxation techniques, electrotherapy, and psychological intervention.28
After completing the acupuncture and psychology-based intervention,21 an evaluation was conducted three months later. The results showed that both the intervention and control groups maintained the initially identified improvements in functional well-being, mental health, and physical health. Finally, over two years, significant changes were identified in all participants of this study in the previously mentioned variables, compared to the initial assessment.21
Adverse eventsThe occurrence of adverse effects was considered in four of the studies.24,25,27,30 Neuromuscular electrical stimulation triggered adverse events such as dizziness, discomfort, headache, muscle spasm, and skin itching.30 On the other hand, TENS produced fewer side effects compared to analgesics,24 and no adverse effects were identified after acupuncture.25 In one study, a similar profile of adverse effects was found, although the data were not presented by the study itself.27
Effects on painFive studies were included in the meta-analysis with a total sample size of 327 participants.20,22–25 Analysis was divided into two subgroups: dyspareunia and pelvic pain. The analysis in the dyspareunia group indicated a statistically significant decreased pain score with SMD = 3.1 (95% CI = 1.192, 5.016; p = 0.001; I2 = 95.6%). Also, analysis in the second subgroup indicated a statistically significant decreased pain score in pelvic pain group than control group with SMD = 0.98 (95% CI = 0.220, 1.741, p = 0.012; I2 = 90.1%). Finally, the results indicated a statistically significant decreased pain score in overall therapy group than control group with SMD = 1.27 (95% CI = 0.56, 1.98; p < 0.001; I2 = 92.7%) (Fig. 1).
Effects on quality of life
Five studies were included in the meta-analysis with a total sample size of 460 participants.24,25,27,29,30 The results indicated a statistically significant improvement of quality-of-life score in physical therapy group compared to control group with SMD = 1.52 (95% CI = 0.76, 2.27; p < 0.001; I2 = 94.9%) (Fig. 2).
Risk of publication bias and for individual studies
The funnel plot shows possible evidence of publication bias with Egger’s test for regression intercept with a p-value of 0.009 in pain and 0.014 in quality of life (Supplementary Material 4). The risk of bias within individual studies was determined to be high or critical in nine studies (81.8%)21–28,30 while the remaining studies had a moderate risk of bias (18.2%)20,29 (Table 2). Additionally, according to the GRADE framework, the certainty of the evidence was rated as moderate for all three primary outcomes: dyspareunia, pelvic pain, and quality of life. The assessment included three downgrades due to methodological concerns: (1) risk of bias was rated as serious because most included randomized controlled trials presented high risk according to the RoB 2 tool; (2) inconsistency was downgraded due to substantial statistical heterogeneity (I² > 25%) despite low methodological variability; and (3) imprecision was judged serious because of wide confidence intervals and small sample sizes in several studies. However, the certainty of the evidence was upgraded by two levels, based on two predefined GRADE criteria: (1) a very large standardized mean difference (SMD ≥ 0.8) was observed for all outcomes, and (2) the association was considered strong and unlikely to be explained by residual confounding or publication bias. Therefore, despite methodological limitations, the overall certainty of the evidence was rated as moderate for these outcomes (Table 3).
Risk of bias for included studies.
| ROBINS-I tool results for non-randomized studies | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Authors | Confoundinga | Selectionb | Classification of interventions | Derivation from intended intervention | Missing datac | Outcomes | Selective reportingd | Overall | ||||||
| Bi et al.30 (2018) | Critical | Low | Low | Low | Low | Low | Critical | Critical | ||||||
| Del Forno et al.22 (2020) | Critical | Low | Low | Low | Low | Low | Low | Critical | ||||||
| Sebe et al.28 (2012) | Critical | Low | Low | Low | Low | Low | Critical | Critical | ||||||
| RoB 2 tool results for randomized studies | ||||||||||||||
| Authors | Random sequence (selection bias) | Allocation concealment (selection bias) | Blinding of participants and personnel (performance bias) | Blinding of outcome assessment (detection bias) | Incomplete outcome data (attrition bias) | Selective reporting (reporting bias) | Other bias | Overall | ||||||
| Del Forno et al.20 (2021) | Low | Low | High | Low | Low | Low | Low | Moderate | ||||||
| Farshi et al.29 (2020) | Low | Low | High | Low | Low | Low | Low | Moderate | ||||||
| Gonçalves et al.23 (2017) | Low | Low | High | High | Low | Low | Low | High | ||||||
| Meissner et al.21 (2016) | Low | Low | High | High | Low | Low | Low | High | ||||||
| Mira et al.26 (2015) | Low | Low | High | High | Low | Low | Low | High | ||||||
| Mira et al.24 (2020) | Low | Low | High | High | Low | Low | Low | High | ||||||
| de Sousa et al.25 (2016) | Low | Low | Low | High | Low | Low | Low | High | ||||||
| Zhao et al.27 (2012) | Low | Low | High | High | Low | Low | Low | High | ||||||
Risk of bias from confounding was considered critical when confounding was not inherently controlled for (i.e. no or limited adjustment).
Selection bias was critical when selection into the study was very strongly related to intervention and outcome. This occurred when the study included men with diagnoses other than erectile dysfunction.
Risk of bias due to missing data was considered moderate when there appeared to be a substantial amount of missing data. In these cases, the proportions of and reasons for missing data might differ across interventions groups. Of note, the majority of studies did not report on missing data. The risk of bias for these were classified as low, but could also be considered “unknown”.
Certainty of the evidence (GRADE).
| Outcomes | № of participants (studies) | Risk of bias | Inconsistency | Indirectness | Imprecision | Other considerations | Absolute Effect | Certainty of the evidence (GRADE) |
|---|---|---|---|---|---|---|---|---|
| Dyspareunia | 176 (3 RCTs) | seriousa | seriousb | not seriousc | seriousd | publication bias strongly suspected very strong associatione,f,g,h | SMD 3.1 [1.19 to 5.01] | ⨁⨁◯◯Moderate |
| Pelvic pain | 176 (5 RCTs) | seriousa | seriousb | not seriousc | seriousd | publication bias strongly suspected very strong associatione,f,g,h | SMD 0.98 [0.22 to 1.74] | ⨁⨁◯◯Moderate |
| Quality of life | 460 (5 RCTs) | seriousa | seriousb | not seriousc | seriousd | publication bias strongly suspected very strong associatione,f,g,h | SMD 1.52 [0.76 to 2.27] | ⨁⨁◯◯Moderate |
RCT: randomized clinical trial; SMD: standardized mean difference.
The objective of this review was to evaluate the effectiveness of different physical therapy methods and techniques in reducing the symptoms triggered by endometriosis. Massage therapy combined with perineal stretching, electrotherapy, acupuncture, exercise, and patient education were effective in treating the intensity and frequency of pain and improving the quality of life for patients.
It is currently unknown whether pelvic floor increased tone is a cause or effect of chronic pelvic pain,20,21,24–26,30 dyspareunia,20–22,24–26,30 dysmenorrhea,20,24,26,30 and non-menstrual pain.30 Many studies link these factors to central and peripheral pain sensitization.31 These phenomena would lead to a decrease in nociceptive thresholds and various abnormalities related to the relaxation and coordination of the pelvic floor.31–33 Consequently, increased tone would exacerbate the progression and persistence of these symptoms.32 This would justify the positive results obtained with Thiele massage and perineal stretching,20 neuromuscular electrical stimulation,30 psychotherapy combined with somatosensory stimulation,21 TENS,24,26 and acupuncture,25 as all of these treatments have the ability to act on muscle increased tone.33
Most studies focused on dyspareunia without distinguishing between deep and superficial types. Women with superficial dyspareunia present pelvic increased tone.34 Therefore, the reduction of this symptom following the use of physical therapy techniques suggests that it is related to an inadequate relaxation of the musculature.35,36 However, in cases of deep dyspareunia, these methods do not reduce the symptom, likely because the pain is caused by mechanical pressure or traction on pathological endometrial tissue during sexual intercourse.37 Despite this, TENS-based interventions managed to improve deep dyspareunia,24,26 possibly due to the electrical stimulation provided (and its ability to reduce pain perception according to the Gate Control Theory38). Additionally, self-administered TENS combined with hormonal treatment improved all domains of sexual function.24 Thiele massage and perineal stretching were the only interventions that resulted in changes in the muscular properties of the levator ani muscles.20,22 This is consistent with the physiological effects on muscle tone and contractile area of these techniques.39 In fact, although neuromuscular electrical stimulation,30 Thiele massage and perineal stretching,20,22 and TENS24,26 achieved the best treatment results for different intensities and frequencies of pain, it is worth noting that Thiele massage combined with perineal stretching20,22 was the most effective intervention for treating this symptom, as it managed to reduce these effects with fewer sessions and less intervention time.14,16
TENS24,26 and neuromuscular electrical stimulation30 provide an electrical stimulus that reaches the spinal cord and blocks the harmful stimulus from endometrial inflammation.40 It has been shown that acupuncture-induced analgesia triggers the secretion of endogenous opioids.41 This promotes changes in levels of endorphins, enkephalins, and stress hormones.42 This could explain why pain intensity was reduced.40 Although there is evidence available regarding the placebo effect of acupuncture,42 the results obtained by De Sousa et al.25 would support the therapeutic effect of this method. Finally, somatosensory stimulation combined with psychotherapy improved various painful symptoms.21 The integration of neurophysiology and psychology allows for stimulus modulation based on cognitive goals, effort, and sensory control.43
Neuromuscular electrical stimulation,30 somatosensory stimulation combined with psychotherapy,21 yoga combined with relaxation techniques,23 progressive neuromuscular relaxation under leuprolide therapy,27 and Orem's counseling29 identified improvements in all basic and modular domains,23 mental health,21,27,29,30 physical health,21,27,29,30 and functional well-being.21 However, quality of life extends beyond physical factors,44,45 possibly explaining the lack of improvements in four studies.24–26,28 The interventions that most enhanced quality of life were psychotherapy combined with somatosensory stimulation,21 progressive muscle relaxation combined with leuprolide therapy,27 and Orem's self-care counseling,29 with the latter being the most efficient, achieving improvements in a shorter time.29
It is also noteworthy that despite combining manual therapy, exercise, relaxation techniques, electrotherapy, and psychology,28 no improvements were observed in social functioning, emotional role, mental health, physical role, bodily pain, or general health. This may be due to the multidimensional complexity of these constructs.46,47 Infertility in endometriosis results from pelvic adhesions caused by the disease. A study examined manual therapy using different pressure techniques on these adhered structures.48 These results indicate that TENS24,26 and acupuncture25 did not improve this symptom. It is possible that different combinations of techniques need to be studied to address this condition effectively.
Notably, in four of the studies,20,22,27,29 interventions included patient education. In two of them,20,22 significant improvements were achieved in pain intensity and frequency. In the other two studies,27,28 quality of life improved. Education for patients with persistent pain aims to enhance understanding of pain as a factor influencing physical, psychological, and social well-being.46,47
The main limitation of this systematic review is the small number of available studies. Additionally, heterogeneity was observed in the techniques used, evaluation procedures, and analysis methods. The reviewed studies exhibited low to moderate methodological quality, and some included small sample sizes, limiting the reliability of effectiveness assessments. Moreover, most studies did not evaluate long-term outcomes or consider disease severity among participants. On the other hand, this is the most comprehensive systematic review with meta-analysis and analysis of the largest number of studies on physical therapy treatments for patients with endometriosis.5,49,50
Future research should increase sample sizes and conduct a more comprehensive comparative analysis of physical therapy techniques, incorporating long-term follow-ups.
ConclusionMultimodal physical therapy treatments (massage therapy combined with perineal stretching, electrotherapy, acupuncture, exercise, and patient education) are effective in improving dyspareunia, pelvic pain, and quality of life.
Given the complexity of the symptoms presented in endometriosis, it is crucial to consider both the techniques and the most effective physical therapy methods. However, healthcare professionals providing daily care to these patients must recognize the importance of evaluating each case individually and tailoring treatments to the specific needs of each patient.
PROSPERO registration codeCRD42023432838.
FundingThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Data availabilityThe data presented in this study are available on request from the corresponding author.
Author contributionsA. M.-G., R. L.-R. and P. H.-L. conceptualized and designed the study, drafted the initial manuscript, designed the data collection instruments, collected data, carried out the initial analyses, and critically reviewed the manuscript for important intellectual content. All authors have read and agreed to the published version of the manuscript.
The authors report no conflicts of interest.
None.
