Table 3

Associations between the amount of fat in the lumbar multifidus muscles and LBP in 40 year-old men (n = 199) and women (n = 213).

Unadjusted

Adjusted*

Fat infiltration

LBP year

LBP ever

LBP year

LBP ever

Men and women

Any

1.7 (1.1–2.6)

2.6 (1.5–4.4)

1.8 (1.2–2.8)

2.9 (1.5–5.5)

Slight (grades 1 vs. 0)

1.5 (0.9–2.5)

2.5 (1.4–4.7)

1.6 (0.9–2.8)

2.9 (1.5–5.5)

Severe (grades 2 vs. 0)

3.6 (1.4–9.7)

7.2 (1.6–32.4)

4.1 (1.5–11.2)

9.2 (2.0–43.2)

Severe (grades 2 vs. 1)

2.5 (1.0–6.1)

2.8 (0.7–12.2)

2.5 (1.0–6.4)

3.2 (0.7–14.1)

Men

Any

1.4 (0.9–2.5)

2.8 (1.4–5.9)

1.5 (0.8–2.6)

3.0 (1.4–6.4)

Slight (grades 1 vs. 0)

1.6 (0.8–3.0)

3.1 (1.4–6.4)

1.7 (0.9–3.3)

3.4 (1.5–7.7)

Severe (grades 2 vs. 0)

1.9 (0.5–6.6)

5.7 (0.7–46.9)

1.7 (0.5–6.2)

5.7 (0.7–48.0)

Severe (grades 2 vs. 1)

1.2 (0.4–4.0)

1.9 (0.2–15.2)

1.0 (0.3–3.5)

1.7 (0.2–14.2)

Women

Any

2.4 (1.3–4.5)

2.7 (1.2–6.1)

2.8 (1.4–5.7)

3.2 (1.3–7.9)

Slight (grades 1 vs. 0)

1.6 (0.6–4.1)

2.4 (0.8–6.8)

1.7 (0.7–4.5)

2.7 (0.9–8.1)

Severe (grades 2 vs. 0)

8.3 (1.5–44.5)

9.2 (1.0–84.3)

11.6 (2.0– 66.7)* *

15.1 (1.5–154.3)* *

Severe (grades 2 vs. 1)

5.1 (1.1–22.4)

3.8 (0.5–29.7)

6.7 (1.4–30.8)

5.7 (0.7–46.9)

Data are expressed as odds ratios (95% confidence intervals).

*Adjusted for BMI, physical activity, physical workload, andhours participating in sports;

** time in sports, and body weight remained significant in multivariate analyses.

LBP, lower back pain; LBP ever, had ever experienced lower back pain; LBP year, had experienced lower back pain in previous year.

Kjaer et al. BMC Medicine 2007 5:2   doi:10.1186/1741-7015-5-2