Place of manual therapy in patients with endometriosis: Review of the scope - Discussion

Through this study, we were able to observe that endometriosis is an increasingly frequently diagnosed pathology. Indeed, given the large population concerned, manual therapists are often called upon to treat women with endometriosis. The aim of this study was to review the literature and define the role of manual therapists in supporting patients diagnosed with endometriosis. The clinical and educational value of this review is justified by the significant increase in the number of studies carried out in recent years.

In order to carry out a study combining these two subjects: manual therapy and endometriosis, it was wiser to carry out a scoping review. Using this type of review made it possible to set a well-defined limit in the methodology in order to focus the results on articles that were highly relevant to the subject. The main limitation of the data collection was the inclusion of studies concerning manual therapies and patients diagnosed with endometriosis, regardless of the type of study.

On the subject of the methodological quality of the clinical studies analyzed, most concluded that future studies should be improved on this point. Indeed, there is currently no reference standard for staging endometriosis. Moreover, as there is no correlation between the stage of lesions and the intensity of symptoms experienced by the patient, each tool and technique has its advantages and limitations.

Finally, to rate pain, as with many other complex pains, the visual analog scale (VAS) (Appendix I) appears to be the simplest to use, the most reproducible, the most reliable and the most clinically relevant (21). However, it remains highly subjective, depending on the patient's pain threshold, so it may be complicated to rely on this scale alone (27). To assess quality of life, many studies use the MOS SF-36 (Appendix II), which is widely used and validated in endometriosis (21)(28). This is a 36-item questionnaire divided into 11 questions, assessing health status independently of pathology, sex, age and treatment (29). The questionnaire is not disease-specific. It assesses 8 dimensions (Appendix III):

1. physical activity (PF);

2. limitations due to physical condition (RP);

3. physical pain (BP);

4. perceived health (GH) ;

5. life and relationships with others (SF) ;

6. mental health (MH);

7. limitations due to psychological state (RE) ;

8. changes in perceived health compared to one year earlier (HT).

However, there are 2 specific tools for assessing quality of life, designed for women suffering from endometriosis, called EHP-5 (30) or EHP-30 (21)(31). The EHP-5 (Appendix IV) is a simple questionnaire containing just 11 questions to study how the patient experiences her endometriosis. And the longer version is the EHP-30 (Appendix V), which has more questions about life in general: appetite, depression, anger, etc.

Finally, in all studies, post-treatment assessments are short-term: at the latest within a month of treatment, but often well before (10)(16)(19)(23)(25). We are therefore not in a position to know whether the treatment is long-lasting or effective over several cycles. Especially in the case of cyclic pain, it would be interesting to see over how many cycles the treatment has an effect.

First, chronic or cyclical pelvic pain in patients with endometriosis and their quality of life were analyzed, listed in Table II.

Acupuncture, osteopathy, pelvic massage therapy and transcutaneous neurostimulation (TENS) have been shown to improve cyclical pelvic pain (10)(16)(18)(20)(22)(24), the most common and disabling symptom for patients, which causes them severe pain and can handicap their ability to manage their daily lives. Acupuncture, TENS and osteopathy, in particular, have a real positive impact on patients' quality of life (10)(18)(19)(23)(24). The treatments used are specific to each therapy, but all manual treatments have one thing in common: touch. The skin allows us to experience touch, and is our primary mode of communication. Numerous experimental studies have highlighted the analgesic effect of touch and its positive impact on patients' anxiety management. This highlights the therapeutic potential of touch (35)(36).

Osteopathy shows significant improvement in the physical and psychological dimensions of patients with endometriosis (10). One study showed significant improvements (assessed by the MOS SF-36) with osteopathy in different areas (19):

• a reduction in the intensity of physical pain and its impact on daily life;
• patients perceive themselves to be in better health (following a self-assessment) physically: better vitality, energy and less fatigue and psychologically: less anxious, less depressed, ... ;
• they feel less limited in their lives and their relationships with others, and can participate more in social activities;

Osteopathy, on the other hand, has shown no improvement in :

• physical activity, whether for daily activities such as walking, climbing stairs, etc., or for activities of moderate or high intensity;
• discomfort in everyday activities, due to physical or psychological problems.

The techniques used are mainly on the bony framework of the pelvis and spine: sacrum, pubis, lumbar vertebrae, etc. Practitioners also use global visceral techniques and more specific techniques for the colon and small pelvis. Not all the techniques are clearly described, but they do offer avenues of treatment for patients with endometriosis-related symptoms (16)(18)(19)(20). Moreover, osteopathy has been shown to have a holistic approach, enabling the patient's bio-psychosocial side to be taken into account (34). On the one hand, this is achieved by the length of the consultation (30 minutes to 1 hour), which is conducive to discussion and puts the patient at ease. On the other hand, osteopathic students receive in-depth instruction in touch right from the start of their studies, as osteopaths rely primarily on listening and touch to treat their patients. In addition to all these positive aspects, touch is also said to help create, strengthen and maintain the relationship between patient and practitioner (37). Osteopathy would therefore appear to be a complete and justified manual therapy in the multidisciplinary management of patients with endometriosis.

We have already seen that patients have a long medical history before being diagnosed with endometriosis (6). This often hampers their trust in the medical profession, which needs to be restored (21). These women need support to help them tolerate their symptoms and learn to live with endometriosis. This includes advice on physical activity, avoiding certain foods, etc. (23)(24)(32) We also need to promote treatments with a bio-psychosocial approach that encourages hope, self-efficacy and self-management, and those that provide pain education. Pain management responds to the bio-psychosocial model in a holistic approach, with sustained attention to the patient (22)(33)(34). They need to find therapists who have time for them and are open to discussion, as is the case with certain manual therapies such as osteopathy and acupuncture. Therapists must help them to cope with their illness, without forgetting to put them at ease, listen to them and, of course, not judge them.

We have seen that both complementary and non-complementary therapies combine a technical act with a human act. The effectiveness of therapeutics also depends, in varying proportions, on the human act. A multi-disciplinary approach to care is becoming essential, particularly for patients suffering from endometriosis (10). It has been shown that to help a patient with endometriosis, a multidisciplinary team should include a sexologist and a psychologist (24). This enables the psychological impact of the disease to be addressed, and helps patients find a climate of trust in which they can talk freely.

As we have already seen, endometriosis is a gynecological pathology encompassing a wide range of symptoms. The most recurrent symptoms are :

• dysmenorrhea ;
• dyspareunia ;
• dysuries ;
• dyschezia ;
• chronic fatigue ;
• low morale ;
• depressive symptoms ;
• irritable bowel symptoms: transit problems, bloating, ... ;
• pain on walking; ... (5)(7)(21)(32).

The articles reviewed above focus on the evolution of pelvic pain and patients' quality of life, but a few studies have also analyzed the evolution of other symptoms. We have examined this in Table 2, in the secondary data column.

Firstly, osteopathy shows improvements on digestive symptoms thanks to visceral techniques and techniques on the bony frame: pelvis, lumbar, ... The study does not explain on which specific symptoms progress is found: dyschezia, transit disorders, bloating, ... (19)(20) In any case, all these symptoms are particularly present during menstruation. Reducing digestive problems would therefore improve the menstrual period for patients, as they would have fewer symptoms to manage at the same time.

Moreover, empathy and communication skills are among the qualities of manual therapists (38)(39)(40). They increase patient satisfaction, and improve diagnosis and treatment. In fact, personalized patient support based on listening skills enables the activation of psychological factors leading to a relationship of trust between practitioner and patient. In particular, this alliance enables patients to improve the psychological side of the disease: less stress, better self-image, etc.

Physical therapies, particularly internal techniques, have been shown to have a positive effect on dyspareunia (25). This is one of the symptoms for which women feel most helpless, and they find it hard to find places where they can talk freely about it and find solutions.

The improvement of all these symptoms would have a particular influence on patients' fatigue. With improved physical symptoms, reduced stress, psychological support, trusted therapists, etc., patients seem less and less tired, as they feel more reassured about their pathology (10)(20)(23) (26).

Unfortunately, none of the studies reviewed showed a positive impact on patients' urinary symptoms: dysuria, leakage, etc. (25) Even if these symptoms are overlooked by women (41), they are often very disabling and painful. It also plays a part in their cyclical pain, as pseudo-cystitis often occurs during menstruation (41).

Thanks to all this, we understand that the treatment of women with endometriosis is geared towards managing crises and improving their living conditions. This means that the role of manual therapists is particularly preventive.

Firstly, according to the guidelines for the construction of a scoping review, this review did not assess the methodological quality of the included studies. Estimating and analyzing the level of evidence of the articles is therefore inconceivable (42).

Secondly, a major bias in this study is that the author of the dissertation was the only person to carry out the research, select the articles and analyze the results. A minimum of 2 people is normally recommended, as this was a graduation dissertation with limited resources and time.

In addition, the study has several limitations in terms of article selection. No date was defined when searching for articles in the various databases. This allowed us to have a larger number of articles. We could therefore see that studies cited each other (10)(19)(20)(22)(24). It is important to highlight another publication bias, namely the inclusion of articles written in both English and French. As a result, twelve articles were excluded even though they could have provided useful information for our research.

In addition, it is fair to assert the potential presence of biases arising during the planning, collection and analysis phases of the included studies. Indeed, these biases tend to reveal only the favourable effects of manual therapy in the management of patients with endometriosis. These effects distort the neutrality of this study (43).

On the other hand, we wanted to stand out from the crowd by searching grey literature sites, which added 2 extra data points.

It should be remembered that, when it comes to the evaluation of physical treatment studies, blind and double-blind studies are very difficult, if not impossible, to achieve. The validity of the placebo concept is also complex (10)(23)(44)(45)(46). The lack of comparative efficacy of the different manual techniques used in clinical studies is therefore one of the main areas for improvement in future research.

Moreover, the authors call for a systematization of the treatment protocol used (16)(24). However, this runs counter to osteopathy's patient-centred approach (33)(34). It is therefore a complicated path to follow, particularly in osteopathy, but one that can be more easily followed in other manual therapies which have treatment routines depending on the reason for consultation, such as acupuncture, massage therapy, ... Yet this would improve a major area highlighted in several studies: therapist training in the management of patients with endometriosis. As the physiopathology is not known, it is complicated to educate on the manual treatment to be carried out. Manual therapists must be specifically trained and qualified to help patients avoid pain using cognitive and/or behavioural models, not forgetting active listening and empathy for the emotional component of the patient's illness.

Finally, several studies show that the positive results of manual therapy are associated with the stage of endometriosis: mild, moderate or severe. The authors therefore call for future research dedicated to separating patients according to the progress of disease lesions, symptoms present, ... (10)(19)(20)(24)