A comparison of statistical associations between oedema in the lumbar fat on MRI, BMI and Back Fat Thickness (BFT)

Abstract

PurposeTo compare the relationship between obesity markers Body Mass Index (BMI) and Back Fat Thickness (BFT) and oedema in the lumbo-sacral subcutaneous adipose tissue.Patients and methodsA retrospective study was performed of consecutive Magnetic Resonance Imaging examinations on 149 adults (95 females and 54 males) scanned at 1.5T between October 1 and December 31, 2010. The extent of oedema was graded from 1 to 8 based on the number of involved anatomical segments on the Fat Sat sequence. A vertebra and the disc immediately inferior or any of the upper, middle or lower third of the sacrum was assigned 1 unit. BFT was measured superiorly at the upper border of L1 (BFT L1) and inferiorly at the lower border of L5 (BFT L5) on the T1 weighted image. BMI was computed at the time of the examination. The data were analysed using StatPlus 2009. The association between variables was evaluated using univariate and multivariate regression.Results68 patients (45.6%), 50 females (33.6%) and 18 males (12.0%) were found to have oedema. Weight (p = 0), BMI (p < 0.001), BFT L1 (p < 0.001), BFT L5 (p < 0.001) and age (p = .01) were significantly associated with oedema. On forward stepwise multiple regression significant independent variables predicting oedema were found to be BMI, BFT L1 and Age. ANOVA indicated that BMI explained 23.6% (F = 45.5, p = 0), BFT L1 22.7% (F = 43.2, p = 0) and age 4.7% (F = 7.4, p = 0.007) of the variance of oedema.ConclusionsObesity markers BMI and BFT L1 are significant independent variables predicting oedema. Oedema is predicted to a variable extent by fat at different sites. The oedema may be, in part, a consequence of obesity.

Quantifying paraspinal muscle tone and stiffness in young adults with chronic low back pain: a reliability study

“…Thus, the measurements taken at the lower lumbar levels may reflect greater contribution from superficial soft tissue than those at the upper levels. This outcome is supported by a previous study of MRI images that indicated, in the absence of spinal oedema, that the soft tissue above the paraspinal muscles in adults age between 22–81 years old was thicker at L 5 than that at L 1 42 . If such a finding also applies to the sample population of the current study, it would provide a possible explanation for the decreasing muscle tone and stiffness from L 1 to L 5 .…”

When an incidental MRI finding becomes a clinical issue

“…With respect to clinical parameters, studies have shown the association between PLSE and increased body weight, as well as an increased body mass index (BMI), and back fat thickness, suggesting a relationship between PLSE and obesity [1,[4][5][6][7][8]. These data confirm the anecdotal radiological experience that PLSE is commonly encountered in obese patients.…”

“…For the vast majority, there was a statistically significant relationship between PLSE and its extent and the patients' BMI. Because of this relationship, which has also been demonstrated in previous studies, several authors have formulated hypotheses to provide explanations for the occurrence of PLSE in obesity [1,[4][5][6][7][8][9][10]. This includes various cascades of pathophysiological changes on a macrovascular, microvascular, hormonal, and molecular levels [1,[4][5][6][7][8][9][10].…”

“…The whole image stack of the sagittal STIR sequence was used to confirm or to rule out the presence of PLSE, which was defined as diffuse STIR-hyperintense signal changes within the deep posterior lumbar subcutaneous tissue that did not reach the superficial fat layers [1,2,[4][5][6][7][8][9][10][11]. PLSE was also defined by its location along the fascia plane next to the thoracolumbar fascia and posterior to the spinous process, at the midline, and extending laterally [1,2,[4][5][6][7][8][9][10][11]. Any edema was graded according to its craniocaudal extension with respect to the vertebral bodies from 1-5 (i.e., from one to five vertebral levels), and was consequently classified as monosegmental, one vertebral level, or multisegmental, two or more vertebral levels ( Fig.…”

Lomber subkutan yağ doku kalınlığının spinopelvik parametrelerle ilişkisi

“…In parallel to findings of the present study, Klare et al 6 also reported higher average subcutaneous adipose tissue thickness for women. Similarly, another study in which the relationship between the BMI values of 149 individuals and lumbar adipose tissue thickness at both L1 and L5 levels were evaluated, it was found that women's adipose tissue thickness was higher than that of men 14 . This finding could be explained by the fact that in women estrogen receptors are more common and androgen receptors are found less in subcutaneous adipose tissue, while in men androgen receptors are more predominant in visceral adipose tissue 21 .…”