An investigation of the reproducibility of ultrasound measures of abdominal muscle activation in patients with chronic non-specific low back pain
- 240 Downloads
Ultrasound (US) measures are used by clinicians and researchers to evaluate improvements in activity of the abdominal muscles in patients with low back pain. Studies evaluating the reproducibility of these US measures provide some information; however, little is known about the reproducibility of these US measures over time in patients with low back pain. The objectives of this study were to estimate the reproducibility of ultrasound measurements of automatic activation of the lateral abdominal wall muscles using a leg force task in patients with chronic low back pain. Thirty-five participants from an existing randomised, blinded, placebo-controlled trial participated in the study. A reproducibility analysis was undertaken from all patients using data collected at baseline and after treatment. The reproducibility of measurements of thickness, muscle activation (thickness changes) and muscle improvement/deterioration after intervention (differences in thickness changes from single images made before and after treatment) was analysed. The reproducibility of static images (thickness) was excellent (ICC2,1 = 0.97, 95% CI = 0.96–0.97, standard error of the measurement (SEM) = 0.04 cm, smallest detectable change (SDC) = 0.11 cm), the reproducibility of thickness changes was moderate (ICC2,1 = 0.72, 95% CI 0.65–0.76, SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes from single images with statistical adjustment for duplicate measures was poor (ICC2,1 = 0.44, 95% CI 0.33–0.58, SEM = 21%, SDC = 66.5%). Improvements in the testing protocol must be performed in order to enhance reproducibility of US as an outcome measure for abdominal muscle activation.
KeywordsUltrasound Abdominal muscles Reproducibility Agreement Reliability
This study was funded by the Physiotherapy Research Foundation, Australian Physiotherapy Association. Leonardo O. P. Costa is a PhD student supported by CAPES—Ministério da Educação—Brazil and Pontifícia Universidade Católica de Minas Gerais—Brazil; Chris G. Maher and Paul W. Hodges hold research fellowships funded by the National Health and Medical Research Council of Australia.
- 1.ACSM (1995) ACSM’s guidelines for exercise testing and prescription. Williams and Wilkins, BaltimoreGoogle Scholar
- 3.Beazell JR, Grindstaff TL, Magrum EM, Cullaty M, Hart JM, Shen FH (2006) Comparison of clinical test and real time ultrasound evaluation of muscle contraction in normals and patients with low back pain. J Man Manip Ther 14:168–169Google Scholar
- 6.Costa LOP, Maher CG, Latimer J, Smeets RJEM (2009) Reproducibility of rehabilitative ultrasound imaging for the measurement of abdominal muscle activity: a systematic review. Phys Ther (in press)Google Scholar
- 10.Ferreira ML, Ferreira PH, Latimer J, Herbert RD, Hodges PW, Jennings MD, Maher CG, Refshauge KM (2007) Comparison of general exercise, motor control exercise and spinal manipulative therapy for chronic low back pain: a randomized trial. Pain 131:31–37. doi: 10.1016/j.pain.2006.12.008 PubMedCrossRefGoogle Scholar
- 13.Ferreira PH, Ferreira ML, Maher CG, Refshauge K, Latimer J (2003) Clinical ultrasound test for transversus abdominus thickness: investigation of reliability In: 13th biennial conference—musculoskeletal physiotherapy Australia. Sydney, AustraliaGoogle Scholar
- 14.Hides JA, Miokovic T, Belavy DL, Stanton WR, Richardson CA, Hides JA, Miokovic T, Belavy DL, Stanton WR, Richardson CA (2007) Ultrasound imaging assessment of abdominal muscle function during drawing-in of the abdominal wall: an intrarater reliability study. J Orthop Sports Phys Ther 37:480–486PubMedGoogle Scholar
- 20.Kidd AW, Magee S, Richardson CA (2002) Reliability of real-time ultrasound for the assessment of the transversus abdominis function. J Gravit Physiol 9:131–132Google Scholar
- 26.Mannion AF, Pulkovski N, Gubler D, Gorelick M, O’Riordan D, Loupas T, Schenk P, Gerber H, Sprott H (2008) Muscle thickness changes during abdominal hollowing: an assessment of between-day measurement error in controls and patients with chronic low back pain. Eur Spine J 17:494–501. doi: 10.1007/s00586-008-0589-x PubMedCrossRefGoogle Scholar
- 29.Pietrek M, Sheikhzadeh A, Hagins M, Nordin M (2000) Evaluation of abdominal muscles by ultrasound imaging: reliability, and comparison to electromyography. Eur Spine J 9:309Google Scholar