INFLUENCE OF POSTOPERATIVE ADHESIONS AFTER CAESAREAN SECTION ON CHRONIC LOWER BACK PAIN – A PILOT STUDY OF OSTEOPATHIC MANIPULATIVE TREATMENT

Background: Despite the prevalence of abdominal adhesions after a caesarean section, there exist few postoperative treatment approaches which specifically target adhesions or establish their connection with chronic lower back pain (cLBP). Aims: To investigate if the osteopathic approach of treating adhesions after a caesarean section reduces existing cLBP symptoms and alleviates associated pain. Methods: The subjects received two 30-minute treatments with a one week pause between treatments. The intervention group A (n=18), those who received osteopathic treatment, were compared to a control group B (n=16), who received scar treatment using traditional physiotherapy. The evaluation of subjective (pain intensity with a numeric rating scale, or NRS) and objective (symptom evaluation using the Oswestry Low Back Pain Questionnaire) parameters was accomplished using questionnaires before and after the treatments. Results: Pain intensity reduced clinically relevant in group A by MA21=-2.6; SDA21=1.33 on the NRS. The average Oswestry Disability Index (ODI) in group A decreased from M1=18.3%; SD1=7.8 to M2=6.2%; SD2=6.2. In group B, the decrease from M1=19.1%; SD1=11.1 to M2=14.0%; SD2=10.1 was significantly smaller (p=0,005). Conclusions: Postoperative adhesions could cause cLBP. Treatment of adhesions using osteopathy results in a significant reduction of pain symptoms for cLBP. Due to the sample size calculation, further studies addressing adhesions and chronic lower back pain would be recommended.


Background
Numerous studies show that peritoneal adhesions form after an abdominal operation in between 50% and 95% of cases [1][2][3]. Despite the development of various surgical and pharmacological methods to lower the risk of adhesions forming, long-term postoperative ailments, such as digestive issues, back pain and infertility, can be observed [2,4,5]. In the case of adhesions forming during the healing process of the peritoneum, growths form between the peritoneal fascia, which can harden into fibrous structures. This can result in loss of mobility and flexibility in nearby structures [6][7][8]. Manual therapy treatments for such adhesions are rarely found in existing research [9]. Chapelle and Bove dealt concretely with the visceral mobilisation of adhesions in studies with rats [9,10], while in one pilot study, Probst examined the influence of osteopathic treatment on postoperative recovery after a gastrointestinal operation [11]. Several case studies and studies show that treatment of postoperative scars can reduce individual pain [12][13][14]. This study is concerned with the osteopathic treatment of postoperative adhesions after a caesarean section and the effect of such treatment on chronic lower back pain (cLBP) as compared to scar treatments using traditional physiotherapy.

MATERIAL AND METHODS
This single-blind, block randomised, clinical study examined two groups, namely, the intervention group A (osteopathy) and a control group B (physiotherapy), which received two 30minute treatments one week apart. Group A was comprised of 18 subjects and group B of 16 subjects. Evaluation of the subjective (pain intensity with a numeric rating scale, or NRS [15]) and objective (symptom evaluation using the Oswestry Low Back Pain Questionnaire [16,17]) parameters via questionnaire was performed directly prior to the first treatment and one week after the second and final treatment.
Subjects were recruited via osteopathy colleagues and doctors, as well as the social media platform, Facebook. Of the 63 applicants, 34 subjects were selected based on inclusion and exclusion criteria. The study included female subjects between the ages of 20 and 69 who had experienced chronic lower back pain symptoms lasting at least six months [18] and who had undergone a caesarean section as recently as one year ago and, at most, one other abdominal operation, such as a second caesarean section or an appendectomy. After signing a letter of consent, subjects were then block randomised using a lottery in which group A (osteopathic treatment) or B (physiotherapy) was assigned. To prevent distortion of the results, exclusion criteria included more than two abdominal operations, presence of cancer, other physical or physiotherapeutic treatments during the study, and the use of analgesics and/or muscle relaxers as part of a chronic pain therapy during the study. The designation of inclusion and exclusion criteria, as well as treatment in both groups, was performed by the author of this study. All subjects in the study were blind to their corresponding treatment group, as was the statistician with regard to the data, which was neutral in nature (namely, group A and B). The treatment received by group A encompassed three standard osteopathic techniques combined into the authors own scar treatment concept. These techniques are used to relieve adhesions in the tissue and to restore the gliding behaviour of individual layers of tissue with one another. The direct technique [19], with and without the aid of the hip [19], mobilised the adhesions, after which the myofascial release technique [19] was used in combination with fascial unwinding [19]. Group B was treated with a scar massage according to Thomson, as is taught at the Academy of Physiotherapy in Vienna. Thomson describes four techniques for use on the scarred skin and the upper layers of tissue [20].

Statistical methods
Statistical analysis for this study was completed by Dr. Gebhard Woisetschläger. For a description of the random sample, the results of the questionnaire prior to treatment were used, whereby Wilcoxon-Mann-Whitney (WMW) tests, were also used to determine the initial similarity of the two groups. The two-tailed WMW-tests were completed at a level of significance of α=0.05. Changes after treatment were described using the differential values of the chosen parameters between the two periods of evaluation, which were subjected to WMW-tests (dependent variable: differential values; independent variable: group A or group B). Individual categories of the Oswestry Low Back Pain Questionnaire were examined by descriptive statistics, in which the average impairment was more than 25%. Due to both the means and standard deviations of the differential values in both groups, effect sizes were calculated according to Cohen and the sample size calculation was determined using the ARE method for α=0.05 and P=0.80.
The differential values between the second evaluation, after the intervention, and the first evaluation, prior to the intervention, were MA21=-2.6; SDA21=1.3 for group A and B MB21=-1.5; SDB21=1.9 for group B (W=80, p=0.068). The reduction in pain intensity was greater for group A, although the difference between groups was not significant. Figure 1 shows the distribution of these differential values. The mean Oswestry Disability Index in group A decreases from M1=18.3%; SD1=7.8 to M2=6.2%; SD2=6.2. In group B, the decrease  Table 1. Treatment success and maximum treatment success in the ODI categories "pain intensity", "sitting" and "lifting" (n of N of impaired subjects prior to treatment) Most impairments were in the ODI categories "pain intensity", "sitting" and "lifting". The success of the treatments in each group (reduction of impairment) and maximum treatment success (no impairment as of the second evaluation) can be seen in Table 1.

DISCUSSION
In general, the osteopathic treatment of adhesions in subjects with chronic lower back pain after a caesarean section is more effective than the physiotherapeutic scar treatment according to Thomson, as is taught at the Academy for Physiotherapy in Vienna [20], as clearly shown by the total index of the ODI. A clinically relevant reduction in subjective pain intensity could be measured in both groups; by three points in group A and two points in group B on the NRS. Group A, in which the focus lay on the adhesions, experienced a significant improvement in cLBP symptoms. Studies from Chapelle and Bove confirm that using visceral mobilisation, adhesions can be loosened [9] and the associated impact can be lessened [10]. Changes in the microstructure may lead to a modification of the macrostructure and allow the tissue to return to its physiological function [12]. The results of this study confirm this finding since both groups experienced a clinically relevant improvement in pain and Group A a significant decrease in symptoms. In this study, direct, intermittent and pendulum techniques, as well as longitudinal and latitudinal gliding were used with the intention of improving the gliding layers [12], breaking up adhesions in the tissue, creating micro-fissures, and setting a localized inflammation process in motion [21][22][23][24][25] in order to increase collagenase production [26]. In addition, a mixture of MFR and FU was used to reduce pain and tightness in the tissues, to calm the tissue and inflammatory reaction [21] as the result of intense, mechanical stimulation [23,24,[27][28][29], and to quicken the healing and rebuilding processes thereafter [30,31].
At the same time, the pendulum-like motion impulses stimulate and ensure the release of peritoneal fluids and hyaluronan, which helps reduce friction between the organs and the peritoneal layers and facilitate gliding [32][33][34]. Gravitational forces, as they were used here, transfer forces not just longitudinally, but also to neighbouring tissues and adjacent structures [35,36] and, via improved gliding surfaces in the visceral space, have a positive impact on their environment [29,37]. Because the deep, transverse fascia, which is opened in the case of a caesarean section [38], is located directly next to the peritoneum [39], it is possible that the effects of adhesions could hinder its mobility [6] and that the transfer of force to neighbouring fascia and muscles would change [40] and stiffen [41]. Because of the anatomic proximity to the abdominal and back musculature [39], there may be a connection to the thoracolumbar fascia with its many mechanoreceptors [35,39] and high pain sensitivity [42], which plays an important role in cLBP [37,43,44]. The limitations of this study are that all subjects were treated by the author and the lack of prior knowledge about the necessary sample size. Further studies using the sample size calculated in this study and various, neutral therapists for each treatment group are recommended.

CONCLUSIONS
Adhesions as postoperative complications are common in the medical field [1][2][3], and their widely varying effects on the rest of the body are often mentioned in the research [2,[4][5][6][7][8]. Various studies describe positive effects of postoperative scars on the body [11][12][13][14], but studies on the treatment of adhesions are hard to find [9,10]. The results of the pilot study suggest that postoperative adhesions could cause cLBP, since the treatment of adhesions showed a decrease in cLBP. This is shown by the statistically significant ODI and by a clinically relevant reduction in cLBP pain intensity of group A. Due to these results, one can assume that the osteopathic treatment of adhesions and the restoration of gliding layers in the abdomen after a caesarean section would reduce pain and pain symptoms for cLBP.