Comparison of the sonographic features of the abdominal wall muscles and connective tissues in individuals with and without lumbopelvic pain

• Published in: The journal of orthopaedic and sports physical therapy 2013-01, Vol.43 (1), p.11-19
• Main Authors: Whittaker, Jackie L, Warner, Martin B, Stokes, Maria
• Format: Article
• Language: English
• Subjects: Abdominal Muscles - diagnostic imaging; Abdominal Muscles - physiopathology; Abdominal Wall - diagnostic imaging; Abdominal Wall - physiopathology; Adult; Analysis of Variance; Anthropometry; Case-Control Studies; Connective Tissue - diagnostic imaging; Connective Tissue - physiopathology; Cross-Sectional Studies; Female; Humans; Low Back Pain - diagnostic imaging; Low Back Pain - physiopathology; Male; Middle Aged; Muscle Contraction - physiology; Muscle Strength - physiology; Muscle, Skeletal - physiopathology; Pain Measurement; Reference Values; Risk Assessment; Ultrasonography, Doppler - methods; United Kingdom; Young Adult
• ISSN: 0190-6011; 1938-1344
• DOI: 10.2519/jospt.2013.4450

Cross-sectional, case-control study. To measure and compare the resting thickness of the 4 abdominal wall muscles, their associated perimuscular connective tissue (PMCT), and interrecti distance (IRD) in persons with and without lumbopelvic pain (LPP), using ultrasound imaging. The muscles and PMCT of the abdominal wall assist in controlling the spine. Functional deficits of the abdominal wall muscles have been detected in populations with LPP. Investigations of the abdominal wall in those with LPP are primarily concerned with muscle, most commonly the transversus abdominis (TrA) and internal oblique (IO). Because the abdominal wall functions as a unit, all 4 abdominal muscles and their associated connective tissues should be considered concurrently. B-mode ultrasound imaging was used to measure the resting thickness of the rectus abdominis (RA), external oblique, IO, and TrA muscles; the PMCT planes; and IRD in 50 male and female subjects, 25 with and 25 without LPP (mean ± SD age, 36.3 ± 9.4 and 46.6 ± 8.0 years, respectively). Univariate correlation analysis was used to identify covariates. Analyses of covariance (ANCOVAs) and the Kruskal-Wallis test (IRD) were used to compare cohorts (α = .05). The LPP cohort had less total abdominal muscle thickness (LPP mean ± SD, 18.9 ± 3.0 mm; control, 20.3 ± 3.0 mm; ANCOVA adjusted for body mass index, P = .03), thicker PMCT (LPP, 5.5 ± 0.2 mm; control, 4.3 ± 0.2 mm; ANCOVA adjusted for body mass index, P = .007), and wider IRD (LPP, 11.5 ± 2.0 mm; control, 8.4 ± 1.8 mm; Kruskal-Wallis, P = .005). Analysis of individual muscle thickness revealed no difference in the external oblique, IO, and TrA, but a thinner RA in the LPP cohort (LPP mean ± SD, 7.8 ± 1.5 mm; control, 9.1 ± 1.2 mm; ANCOVA adjusted for body mass index, P