PHYSIOTHERAPISTS’ RELIABILITY OF MEASURING INTER-RECTI DISTANCE WITH REAL-TIME ULTRASOUND ACROSS A MIXED WOMEN POPULATION SAMPLE

E. Billis¹, T. Papakonstantinou¹, A. Skoura¹, E. Drakonaki², D.-T. Papanikolaou¹, M. Tsekoura¹, S. Lampropoulou¹, M. Andriopoulou³, S. Xergia¹, T. Bania¹, E. Trachani¹, E. Kortianou⁴, I. Maroulis⁵

¹University of Patras, Laboratory of Clinical Physiotherapy and Research, Department of Physiotherapy, Patras, Greece, ²University of Crete, Anatomy Department, Medical School, Heraklion, Greece, ³General Hospital Asklipieio Voulas, Physiotherapy, Athens, Greece, ⁴University of Thessali, Department of Physiotherapy, Lamia, Greece, ⁵University of Patras, Medical School, Patras, Greece

Background: Separation of rectus abdominis muscles by ultrasound (US) imaging has become a popular clinical measurement and/or outcome measure for physiotherapists (PTs) for monitoring diastasis rectus abdominis (DRA) problems amongst women or postpartum. However, the reliability of measuring inter-recti distance (IRD) via US has not been sufficiently explored in previous reports. Issues such as measurement location, consistency in measurements across parous women (with usually larger IRDs and more ‘fuzzy’ US images) or across a range of abdominal contractions and tasks merit further research.

Purpose: To investigate intra-tester, inter-tester and test-retest reliability of the inter-recti distance measurements utilizing real-time ultrasound across nulliparous and parous women.

Methods: Women around the broader university campus area were invited to participate in the study via advertisements and university-mediated means. Women with severe backache or neurological problems, which could affect their muscle tone, were excluded from the study. Five clinical PTs performed the US measurements, following a training procedure delivered to them by a consultant radiologist specialized in musculoskeletal sonographic imaging, who taught them how to best measure IRD with a General Electric, Versana Active 2-D real-time US model. Four conditions (simulating common resting and exercise tasks) were standardized and tested supine; relaxed position measured at the end of expiration (REST), curl-up with head lift (CU), transversus abdominus activation (TrA) and combined TrA and curl-up (TrA+CU). Three measurement locations were tested in random order; umbilicus, 3cm above umbilicus and halfway between umbilicus and xyphoid process. For intra-tester reliability, each therapist undertook three repeated US measurements across all locations and conditions. For the inter-tester reliability, IRD mean measurements were explored across two testers (at a time) within the same session. Test-retest reliability was explored by repeating all US measurements 5-8 days later. Data were analysed in SPSS with intraclass correlation coefficients (ICC_2,1) and 95% confidence intervals (Cis).

Results: 54 women (33.2±15.2 years-old, BMI: 24.2±3.7), of which 19 (35.2%) were parous participated in the study. Intra-tester reliability across each PT was excellent, with ICCs ranging between 0.913-0.980 and small CIs across all locations and tasks. Inter-tester reliability yielded very good results, with ICCs between 0.761-0.927. Test-retest reliability was also very good across all positions and tasks (ICCs=0.761-0.963) except for one measurement (3cms above umbilicus for the combined TrA+CU task), where reliability was low (ICCs of 0.280 and 0.503 between testers 1 with 3 and 2 with 3, respectively).

Conclusions: Overall, US measurements of IRD by PTs in one resting and three abdominal contraction tasks across parous and nulliparous women was excellent for repeated measurements by the same PT (intra-tester) and very good across raters (inter-tester) within the same and across different sessions (test-retest reliability).

Implications: Physiotherapists, following sonographic training can reliably measure IRD in women with smaller (nulliparous) and larger (parous) IRDs across a range of active and resting tasks. Thus, US measurement of IRD is recommended for routine use in physiotherapy practice, either for monitoring or as an outcome measure across women with DRA problems or postpartum.

Funding acknowledgements: None

Keywords:
Inter-recti distance
Reliability
Ultrasound

Topics:
Musculoskeletal
Pelvic, sexual and reproductive health

Did this work require ethics approval? Yes

Institution: University of Patras, Greece

Committee: Ethical Committee of University of Patras

Ethics number: 13890/24-6-2022