Evidence synthesis showed limited evidence supporting poor baseline transversus abdominis contraction thickness ratio as a treatment effect modifier favoring motor control exercise .
Limited evidence supported that high baseline transversus abdominis lateral slide was associated with higher pain intensity after various exercise interventions at 1-year follow-up .
However , there was limited evidence for the absence of relation between the contraction thickness ratio of transversus abdominis or anticipatory onset of lateral abdominal muscles at baseline and the short- or long-term LBP intensity after exercise interventions .
There was conflicting evidence for a relation between baseline percent thickness change of lumbar multifidus during contraction and the clinical outcomes of patients after various conservative treatments .
Although individual reports suggest that baseline morphometry or activity of transversus abdominis or lumbar multifidus predict clinical outcome of low back pain ( LBP ) , a related systematic review is unavailable .
Therefore , this review summarized evidence regarding the predictive value of these muscular characteristics .
Changes in recruitment of transversus abdominis correlate with disability in people with chronic low back pain
Objectives Although motor control exercises have been shown to be effective in the management of  low back pain ( LBP ) the mechanism of action is unclear . The current study investigated the relationship between the ability to recruit transversus abdominis and clinical outcomes of participants in a clinical trial . Methods Ultrasonography was used to assess the ability to recruit transversus abdominis in a nested design : a sample of 34 participants with chronic LBP was recruited from participants in a r and omised controlled trial comparing the efficacy of motor control exercise , general exercise and spinal manipulative therapy .  Perceived recovery , function , disability and pain were also assessed . Results Participants with chronic LBP receiving motor control exercise had a greater improvement in recruitment of transversus abdominis ( 7.8 % ) than participants receiving general exercise ( 4.9 % reduction ) or spinal manipulative therapy ( 3.7 % reduction ) . The effect of motor control exercise on pain reduction was greater in participants who had a poor ability to recruit transversus abdominis at baseline . There was a significant , moderate correlation between improved recruitment of transversus abdominis and a reduction in disability ( r = −0.35 ; 95 % CI 0.02 to 0.62 ) . Conclusion These data provide some support for the hypothesised mechanism of action of motor control exercise and suggest that the treatment may be more effective in those with a poor ability to recruit transversus abdominis
Evidence synthesis showed limited evidence supporting poor baseline transversus abdominis contraction thickness ratio as a treatment effect modifier favoring motor control exercise .
Limited evidence supported that high baseline transversus abdominis lateral slide was associated with higher pain intensity after various exercise interventions at 1-year follow-up .
However , there was limited evidence for the absence of relation between the contraction thickness ratio of transversus abdominis or anticipatory onset of lateral abdominal muscles at baseline and the short- or long-term LBP intensity after exercise interventions .
There was conflicting evidence for a relation between baseline percent thickness change of lumbar multifidus during contraction and the clinical outcomes of patients after various conservative treatments .
Although individual reports suggest that baseline morphometry or activity of transversus abdominis or lumbar multifidus predict clinical outcome of low back pain ( LBP ) , a related systematic review is unavailable .
Therefore , this review summarized evidence regarding the predictive value of these muscular characteristics .