Abdominal activation during pelvic compression
Due to the prevalence of low back pain, understanding the sacroiliac (SI) joint and its anatomical role are essential in designing patient specific physiotherapy interventions. When dealing with non-specific low back pain (NsLBP) of SI origin current physical therapy approaches typically include lumbopelvic stabilization and compression belts. With this in mind, the authors wanted to determine the effect pelvic compression had on deep abdominal musculature during an active straight leg raise (ASLR). Overall it was shown that despite patients with SIJ pain reporting less pain with compression, the pelvic compression did not alter the muscular activity of the deep abdominal musculature (transversus abdominus and internal oblique) as measured as a percentage change in thickness of TrA and IO.
Thirty participants were recruited into the study. Fifteen patients exhibited unilateral pain near the SIJ and fifteen age and sex matched controls were also included. Ultrasound imaging was used to determine the thickness of the TrA and IO at rest and during the ASLR with and without pelvic compression.
When considering the SIJ, the mechanism for how pelvic compression is not understood. The authors hypothesised that increased pelvic “stiffness” would influence the behavior of the abdominal musculature during movement. Despite this it was shown that there was no significant percentage change of TrA and IO muscle thickness with and without the compression belt. This suggests that although those experiencing symptoms of SIJ pain reported a decrease in pain the compression likely had an effect on the passive structures of the pelvis rather than the muscular response of the abdominals. Taken together, this suggests that as clinicians we should look to incorporate specific localized exercises to improve the dynamic SIJ stability.
> From: Brizzolara et al., Int J Ther Rehab 22 (2015) 9. All rights reserved to International Journal of Therapy and Rehabilitation.Click here for the Pubmed summary.