The effect of experimental low back pain on lumbar muscle activity in people with a history of clinical low back pain: a muscle functional MRI study

摘要: In people with a history of low back pain (LBP), structural and functional alterations have been observed at several peripheral central levels the sensorimotor pathway. These existing might interact way system responds to pain. We examined this assumption by evaluating lumbar motor responses experimental nociceptive input 15 participants during remission unilateral recurrent LBP. Quantitative T2 images (muscle MRI) were taken bilaterally multifidus, erector spinae, psoas segmental (L3 upper L4 lower endplate) conditions: 1) rest, 2) upon trunk-extension exercise without pain, 3) induced clinical pain-side (1.5-ml intramuscular hypertonic saline injections in spinae). Following induction, muscle activity similarly reduced for all three muscles, on both painful nonpainful sides, multiple (P = 0.038). Pain intensity localization from LBP similar as recalled episodes. conclusion, unisegmental exerts generalized widespread decrease This response is consistent previous patterns healthy subjected same paradigm. It striking that inhibitory could be observed, despite presence preexisting musculature results suggest output can modify along course