Investigating Diaphragm Thickness and Mobility in Healthy Parous and Nulliparous Volunteers Using RUSI
Condition: Asymptomatic Condition
MeSH terms: Asymptomatic Diseases
Study type: Observational

Summary: 
      The purpose of this study is to evaluate the intra-rater and inter-rater reliability of
      diaphragm thickness and excursion measurements by applying Rehabilitative Ultrasound Imaging
      (RUSI) in a diverse cohort of healthy women, including nulliparous and parous across varying
      age groups.

      The diaphragm, which is primarily a respiratory muscle, is also considered to contribute to
      spinal stability. Utilizing RUSI, a non-invasive and cost-effective imaging modality, we
      intend to examine diaphragm parameters. Preliminary evidence highlights a potential link
      between diaphragm dysfunction and musculoskeletal conditions such as lumbopelvic pain. This
      research hypothesizes that understanding diaphragm behavior in different pathologies,
      including postpartum recovery and lower back pain, can contribute to tailored rehabilitation
      strategies, potentially benefiting a wide range of clinical conditions, and facilitating the
      assessment of intervention effectiveness. Additionally, this study addresses the lack of
      research on the diaphragm's role in postpartum rehabilitation and offers novel insights into
      its reliability, particularly within this demographic.
    

Detailed description: 
      The diaphragm is the main respiratory muscle but is also considered to contribute
      significantly to trunk stability and posture due to its unique anatomy and coordination with
      other trunk muscles. Rehabilitative Ultrasound Imaging (RUSI) technique provides a safe, and
      cost-effective method for assessing diaphragm muscle function. RUSI is employed in
      musculoskeletal physiotherapy to assess diaphragm thickness or mobility in trunk conditions
      such as lumbopelvic pain, as a method to investigate rehabilitation effectiveness or as a
      biofeedback tool for muscle training. Although, the reliability of RUSI measurements for
      diaphragm thickness and excursion has been previously investigated in healthy populations,
      individuals with pelvic girdle pain and athletes with lumbopelvic pain, its reliability on
      postpartum populations has never been researched. Therefore, this study aims to assess the
      reliability of diaphragm thickness and excursion measurements in healthy women, including
      nulliparous and parous individuals of varying ages, utilizing RUSI.

      This reliability study adheres to Ethical considerations and the Helsinki Declaration and is
      approved by the Research Ethics Committee (R.E.C.) of the University of Patras. The study
      incorporates a robust quality assurance plan, according to the Internal Review Board of the
      Research Ethics Committee (R.E.C.) of the University of Patras, including data checks to
      assess data validation and registry procedures performed by the Data Monitoring Committee of
      R.E.C. of the University of Patras, as well as site monitoring and auditing, to maintain
      protocol adherence and data collection integrity. The accuracy, completeness, and
      representativeness of registry data is assured by the research team, comparing the data to
      preliminary data published in similar reliability studies. A comprehensive data dictionary is
      established among the research team, containing detailed variable descriptions, coding
      information, and normal ranges, ensuring consistency and clarity in data collection.

      RUSI is performed by two trained physiotherapists (with more than 5 years of clinical
      experience in musculoskeletal physiotherapy). The physiotherapists received one-day training
      from a consultant radiologist, specializing in musculoskeletal sonographic imaging, followed
      by several hours of independent and joint practice between the radiologist and
      physiotherapists. A convenience sample of adult women coming from around the broader
      university campus area is invited to participate in the study, via advertisements and
      university-mediated means (emails, e-platform university announcements etc.). Informed
      consent is obtained from all participants. Participants undergo an ultrasound assessment in
      the semi-recumbent position with the Versana Active™ ultrasound system. Anatomical guide
      points are marked by a surgical skin marker for accuracy, and the 2 trained physiotherapists
      perform the assessments according to Boussuges et al. (2020) recommendations. Diaphragm
      thickness is measured using a high-resolution linear transducer in B-mode at the end of a
      full inspiration and full expiration. Diaphragm excursion is assessed using a high-resolution
      curvilinear transducer in M-mode during tidal volume diaphragmatic breathing. A two-minute
      resting interval follows each measurement. During the resting intervals, calipers are placed
      on the captured images according to literature recommendations and measurements are recorded
      and saved. Intra-tester and inter-tester reliability are evaluated by taking 3 consecutive
      measurements per parameter. Operators and subjects are blinded for all measurements taken, by
      covering measurement tables at the edge of the ultrasound screen. An independent researcher
      blinded to the subject identity (the identity of the subject on the ultrasound screen is
      concealed by the operator at the end of the assessment) and the examination procedure is
      responsible for the extraction, and documentation of all variables in a spreadsheet software.

      All patient data are stored anonymously/coded in a secure cloud platform accessed only by the
      research team members. Imputation methods will be applied to address situations where
      variables are missing, uninterpretable, or inconsistent. Any adverse events will be addressed
      and documented, while medical consultation will be accessible during patient assessment
      hours. Any modifications to the study protocol, data collection methods, or other aspects of
      the study will be reviewed thoroughly among researchers and the Internal Review Board of the
      R.E.C., and the study protocol as well as study registration will be adjusted accordingly.
      Statistical analysis of the data will be performed using SPSS software (version 28.0; SPSS
      Inc, Chicago, IL). Reliability will be calculated using intraclass correlation coefficient
      (ICC) assessed with a two-way random effect model (ICC2,1) and 95% confidence intervals.
    

Intervention name(s): Diagnostic Ultrasound Imaging of the diaphragm
Intervention type(s): Diagnostic Test
Intervention description(s): In this reliability study, ultrasound imaging will be utilized by trained physiotherapists to assess diaphragm thickness and excursion. Participants will be positioned in a semi-recumbent position, while the scanning area will be marked with a surgical skin marker according to specific anatomical landmarks recommended, to ensure reproducibility of the procedure. Ultrasound probe will be placed at the zone of apposition to visualize the diaphragm through the liver window.
Diaphragm thickness will be assessed during both full inhalation and exhalation, capturing images in B-mode to measure distance between the diaphragmatic pleura and peritoneal fascia. Diaphragm excursion will be assessed during tidal volume diaphragmatic breathing, using M-mode to track the craniocaudal displacement of the diaphragm during respiratory cycle. Data obtained will contribute to the evaluation of the reliability of diaphragm thickness and excursion measurements for potential future clinical applications.
Observational model: Other
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        The population from which the cohort will be selected consists of generally healthy women
        aged 18 to 60 years affiliated with the university campus area (professors and students
        from all academic levels). This population will be invited to participate through
        advertisements and university-mediated means, including emails and e-platform
        announcements.
      
Keywords: Ultrasound; Diaphragm/diagnostic imaging; Rehabilitation; Parity; Validation Study