Exploring the Effects of Soft Tissue Manual Therapy on Caesarean Section Scar
Condition: Cesarean Section Complications
Study type: Interventional

Summary: 
      Introduction: Caesarean section is one of the most common inpatient surgical procedures.
      Complications of obstetric wounds are estimated to account for 2.8-26.6% of cases. Between 11
      and 15% of women would develop pain and discomfort following a Caesarean section. Manual
      therapies may be an interesting non-pharmacological approach to treating the signs and
      symptoms of scarring complications following a Caesarean section. However, the current
      literature with an in vivo perspective remains modest results for the effects of tissue
      physiology and their effects on pain.

      Method: Using an exploratory "proof of concept" type descriptive design with before and after
      measurements, the immediate and 7-day effects following the application of soft tissue manual
      therapy on the Caesarean section scar will be evaluated. The objectives are to describe and
      explore differences from the effects of soft tissue manual therapy on the viscoelastic
      properties, pressure sensitivity and touch sensitivity of the Caesarean section scar.
      Thirty-eight women aged between 18 and 40 years with a Caesarean section scar who attend
      first-line or specialized obstetrics and perinatal clinics will be recruited.

      Anticipated results This project will document the viscoelastic characteristics, pressure
      sensitivity and touch sensitivity of the C-section scar and surrounding unhealed tissue to
      improve our understanding of the plausibility of the effects of manual therapy, an approach
      used to treat the signs and symptoms associated with C-section scarring.
    

Detailed description: 
      Methods of manual treatment of scars have demonstrated some effectiveness, although the
      effects and physiology by which mechanical forces of the therapist's hand provide benefits
      are poorly understood. This research will improve understanding of certain tissue
      characteristics and physiology elicited during treatment, and provide better conceptual
      explanations of the effects of manual therapies.

      This study consists of 2 steps. The first step consists of the reliability of the Myoton Pro.
      The second step consists to describe and explore the effects of the soft tissue manual
      therapy on viscoelastic properties, touch sensibility and pressure sensibility on the
      Caesarean scar and the unscarred skin.

      Objective(s)

      The main objective of this project is to evaluate the effects of the application of
      mechanical force by the therapist's hand on the Caesarean section scar. The specific
      objectives are to document the following, prior to and following the application of
      mechanical force by the therapist's hand:

        1. Determine the reliability and discrimination of the Myoton Pro.

        2. The viscoelastic properties of the Caesarean section scar and surrounding healthy
           tissues;

        3. The sensitivity of the Caesarean section scar to pressure compared with surrounding
           healthy tissues;

        4. The touch sensitivity of the Caesarean section scar compared with surrounding healthy
           tissue; and

        5. Differences in viscoelastic properties, pressure sensitivity and touch sensitivity
           before and after the independent variable.

      Recruitment Recruitment will be recruited women attending primary care and specialized
      obstetrics and perinatal clinics in the Vaudreuil-Soulanges region, Candiac on the south
      shore of Montreal, Repentigny located in the Lanaudière region and community organizations
      with a perinatal orientation located in the Montreal region. Posters will be put up and
      announcements will be made on the research centre's Facebook page as well as the page
      dedicated to the project. Interested will be able to communicate directly with the student
      researcher via digital platform. A brief description of the implications will be sent using
      digital platform. They will then be asked if they are still interested in participating and
      if they agree to be contacted by the student researcher in order to verify the eligibility
      criteria. The student-researcher will request contact information such as email address and a
      valid telephone number in order to make contact. During this telephone contact, the
      student-researcher will explain the elements of the study, reiterate the free nature of their
      participation and verify the eligibility criteria. The student-researcher will then suggest
      an appointment.

      Data collection Phase 1: Reliability of the Myoton Pro The experimental procedure will take
      place at the Longueuil Campus of the Université de Sherbrooke located in Longueuil. Three
      evaluators will perform the measurements. The investigator will call them Evaluator 1 (E1),
      Evaluator 2 (E2) and Evaluator 3 (E3). E1 will invite participants to lie supine on a
      treatment table. E1 will place a pillow under the participants' knees to reduce the lower
      extremity strain. They will be asked to undress their abdomen to make the scar visible. The
      E1 will locate a point in the centre of the scar and a healthy control point about 2 cm above
      the scar and identify them with an indelible black pencil. The E1 will take four measurements
      of each point alternately using the MyotonPro. E2 will then take four measurements at the
      same points using the MyotonPro using the same procedure. Finally, this procedure will be
      repeated by E3.

      Phase 2:

      The experimental procedure will take place at the AXiO sports medicine clinic in
      Vaudreuil-Dorion, the FDL massage therapy and osteopathy clinic located in Candiac, the
      Parent-aise osteopathy clinic located in Repentigny and the ENOSI osteopathy centre located
      in Montreal. Measurements of the dependent variables with the MyotonPro, Von Frey's algometer
      and microfilaments will be taken by a research assistant. She will be trained beforehand on
      the following elements: 1) the use of Von Frey's microfilaments, 2) the use of the algometer,
      3) the use of the Myoton Pro, 4) their application on the tissue and scar points previously
      identified by the student researcher, 5) computer data entry. The POSAS questionnaire will be
      administered by the student researcher, who will explain it to the participants.

      Upon their arrival, participants will be greeted by the student researcher. The student
      researcher will give them the consent form, reiterate the free and informed nature of the
      questionnaire and make sure they understand it. She will ensure that the form is signed. She
      will then give them the POSAS questionnaire to which will be annexed to the socio-demographic
      and clinical data questionnaire.

      The student-researcher will invite the participants into a room and they will then lie supine
      on a treatment table. She will then invite the participants to undress the lower abdominal
      area. The student-researcher will make sure that the Caesarean section scar and the area
      around it are clearly visible. She will place a pillow under the participants' knees for
      maximum reduction of any tension surrounding the scar, which will lengthen the lower limbs.

      The student-researcher will identify five points on the Caesarean scar, five points on the
      upper scar border, five points on the lower scar border and five additional points about 2 cm
      above the scar in the healthy surrounding tissue and mark them with a nontoxic pencil. She
      will then leave the room.

      Using Von Frey's microfilaments, the research assistant will make an initial assessment of
      the sensitivity to touch of the five points of the Caesarean scar and the healthy tissue.
      Using the Myoton Pro, the research assistant will make an initial measurement of the
      viscoelastic properties of the healthy, scarred tissue points and the upper and lower scar
      edges (for a total of 20 points). Then, the research assistant will use the algometer placed
      perpendicularly to each identified point and will make a first measurement of pressure
      sensitivity on the surrounding tissue surfaces and on the Caesarean section scar (T0). In
      order to ensure reproducibility, 3 measurements per point will be taken before the manual
      technique is applied. The measurements will be recorded in the participant's file, without
      the knowledge of the student researcher.

      The student-researcher will enter the room. She will place the glove with the force sensor on
      the thumb of her right hand. She will evaluate the Caesarean section scar and identify the
      most rigid scar areas when compression is applied. In these identified areas, the
      student-researcher will apply the manual therapy procedure described in the independent
      variable (compression + shear) section. This procedure will be applied to all identified
      rigid areas of the Caesarean section scar.

      This procedure will take 20 minutes (approximately 2 minutes per rigid area). After this
      time, the student-researcher will remove the force sensor and leave the room. The research
      assistant will perform the evaluation of Von Frey's microfilaments, measurements of
      viscoelastic properties using the Myoton pro and pressure sensitivity using the algometer at
      the same tissue and scar points (T1). This same procedure will be performed again seven days
      later, before (T2) and after the procedure (T3). Following the last measurement time, a
      complete treatment of the scar area and surrounding tissues will be offered to the
      participants. Note that an anonymous code will be assigned to each participant and their
      information. The research assistant will collect the data using an Excel file. The data from
      the MyotonPro will be collected and automatically saved in a computer folder and later merged
      into the Excel file.

      Sampling The sample of the accessible population will be drawn from a non-probabilistic
      convenience sample.

      Sample size

      Phase 1:

      The sample size was determined by assuming a predetermined intra-participant standard
      deviation (Bland and Altman, 1996). Using Bland's formula for repeatability studies, the
      following parameters were considered: 1) an intra-participant standard deviation of 10%; 2)
      four measurements at a point on the scar and four measurements at a healthy control point two
      centimetres above the scar per participant and per evaluator; and 3) three evaluators. Using
      these parameters, the sample size required to estimate the magnitude of the 95% confidence
      interval of the precision estimates is 18 participants.

      Phase 2:

      The exploratory component of this project will provide data with respect to viscoelastic
      properties, and sensitivity to pressure and touch. Since to our knowledge, no study could
      inform the sample size calculation, the investigator assume a medium effect size with a power
      of 80% and a type I error of 5%. Given these assumptions, the sample size requires 32
      participants. Anticipating a 10% drop-out rate, the resulting total sample size is 38
      participants.

      Analysis plan

      Phase 1:

      In order for the intraclass correlation coefficient (ICC) to be established accurately, the
      prerequisites of the analysis of variance (ANOVA) must be met. The normality of the
      observations will be checked using the Kolmogorov-Smirnov test. Using a two-factor ANOVA, the
      intra-participant standard deviation, repeatability coefficient and ICC will be calculated to
      establish intra- and inter-rater reliability.

      Phase 2:

      Descriptive analyses will be conducted based on socio-demographic data and the
      characteristics of the participants. The continuous variables, if normally distributed, will
      be summarized using means and standard deviation. The continuous variables, if not normally
      distributed, will be summarized using medians and intervals. Ordinal and discrete variables
      will be summarized using percentages.

      With respect to the Caesarean section scar, the viscoelastic properties and sensitivity to
      pre- and post-pressure will be compared using a multi-level longitudinal regression model, if
      data is normally distributed. Otherwise, nonparametric tests will be performed. The pre- and
      post-intervention touch sensitivity of the Caesarean section scar will be compared using the
      Friedman test. A student's paired test will be used to compare POSAS, viscoelastic properties
      and pressure sensitivity of healthy tissues means. The Wilcoxon rank test will be used for
      the touch sensitivity of healthy tissues. Finally, the comparison between the Caesarean scar
      and healthy tissues will be made with the student's test in the case of a normal distribution
      of data. Otherwise, a nonparametric test will be performed.
    

Intervention name(s): Soft tissue manual therapy
Intervention type(s): Other
Intervention description(s): The intervention is a type of massage.
Intervention model: Single Group Assignment
Intervention model description: An exploratory descriptive design with before and after measurements.
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Caesarean; Manual therapy; Thresholds; Viscoelastic properties; scar