D'hooge Roseline, Cagnie Barbara, Crombez Geert, Vanderstraeten Guy, Dolphens Mieke, Danneels Lieven
Department of Rehabilitation Sciences and Physiotherapy, Ghent University, 3B3, De Pintelaan 185, 9000 Ghent, Belgium.
Man Ther. 2012 Dec;17(6):584-8. doi: 10.1016/j.math.2012.06.007. Epub 2012 Jul 10.
Lumbar muscle degeneration is a common feature in non-specific low back pain (LBP). It is hypothesized that degenerated muscles might compromise spinal stability and lead to further injury/pain. However, little is known about lumbar muscle morphometry after resolution of LBP. Therefore, this study investigated the extent of lumbar muscle atrophy and fatty infiltration in individuals who are at risk for a recurrence of LBP. Thirteen participants in remission of unilateral recurrent LBP were compared to 13 healthy controls, comparable for age, weight, length and level of physical activity. Total, lean muscle and fat cross-sectional area (CSA) of lumbar multifidus (MF), erector spinae (ES) and psoas (PS) were investigated on T1-weighted Magnetic Resonance Imaging (MRI), bilaterally and at 3 lumbar levels (L3 upper, L4 upper and L4 lower endplate). In addition, a muscle-fat-index (MFI) was calculated reflecting the amount of fatty infiltration in lean muscle tissue. No significant differences for total, lean muscle and fat CSA were found between people in remission of recurrent LBP and the control group. Conversely, MFI was increased bilaterally at the 2 lowest lumbar levels. There were no differences between the previously painful and non-painful side of the LBP group for any of the parameters. These results show a generalized increase in intramuscular fatty infiltration in lean muscle tissue in the absence of macroscopical signs of muscle degeneration after resolution of LBP. These findings reflect a decreased muscle quality, but not quantity, and might indicate a pathophysiological mechanism contributing to recurrence of LBP.
腰肌退变是非特异性下腰痛（LBP）的常见特征。据推测，退变的肌肉可能会损害脊柱稳定性，并导致进一步的损伤/疼痛。然而，对于LBP缓解后腰肌形态学的了解却很少。因此，本研究调查了有LBP复发风险的个体中腰肌萎缩和脂肪浸润的程度。将13名单侧复发性LBP缓解期的参与者与13名年龄、体重、身高和身体活动水平相当的健康对照者进行比较。在T1加权磁共振成像（MRI）上，对双侧3个腰椎水平（L3上、L4上和L4下终板）的腰多裂肌（MF）、竖脊肌（ES）和腰大肌（PS）的总横截面积（CSA）、瘦肌肉横截面积和脂肪横截面积进行了研究。此外，计算了肌肉脂肪指数（MFI），以反映瘦肌肉组织中的脂肪浸润量。复发性LBP缓解期的人与对照组之间在总横截面积、瘦肌肉横截面积和脂肪横截面积方面未发现显著差异。相反，在最低的两个腰椎水平，双侧MFI均升高。LBP组中先前疼痛侧和未疼痛侧在任何参数上均无差异。这些结果表明，在LBP缓解后，在没有肌肉退变宏观体征的情况下，瘦肌肉组织内的肌内脂肪浸润普遍增加。这些发现反映了肌肉质量而非数量的下降，可能表明存在导致LBP复发的病理生理机制。
