Research Paper: Lateral Abdominal Muscles Asymmetry in Female Patients With Chronic Non Specific Unilateral Low Back Pain Practicing Hollowing Exercises

  • Maryam Zolghadr MSc., Department of Physiotherapy, School of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
  • Sedighe Kahrizi Associate Professor, Department of Physiotherapy, School of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
  • Alireza Soltanian Associate Professor, Department of Biostatistics and Epidemiology, School of Health, Hamadan University of Medical Sciences, Hamadan, Iran.
Keywords: Low back pain, Abdominal muscle, Symmetry, Exercise, Hollowing, Ultrasonography


Introduction: With regard to unilateral pain in some patients with low back pain (LBP), it is advisable to evaluate asymmetrical thickness of lateral abdominal muscles. This study aimed to compare abdominal muscle thickness asymmetry in patients with non specific unilateral LBP during rest and practicing several stabilizing exercises with hollowing maneuver.
Materials and Methods: This research has a case-control design. Sixteen female subjects with left and right unilateral LBP and 8 healthy subjects participated in this study. Internal oblique, external oblique and transversus abdominal muscles thickness were evaluated by ultrasound imaging technique in both sides of the subjects’ bodies during rest and hollowing maneuver with 3 stabilizing exercises; bridging, four point kneeling and abdominal crunch.
Results: According to the findings, abdominal muscle thickness asymmetry during exercises was more than resting position in two groups but it is not statistically significant. Also, no significant difference was seen between case and control groups regarding abdominal muscle thickness asymmetry.
Conclusion: Considering the appearance of asymmetry in healthy subjects, it seems that asymmetry in abdominal muscles cannot be interpreted as pathologic phenomena in LBP subjects.


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How to Cite
Zolghadr M, Kahrizi S, Soltanian A. Research Paper: Lateral Abdominal Muscles Asymmetry in Female Patients With Chronic Non Specific Unilateral Low Back Pain Practicing Hollowing Exercises. jmr. 11(2):133-139.
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