Table 2 Results of linear mixed model investigating the relationship between muscle volume (mm3) and group (pain vs. asymptomatic), accounting for side (left or right), muscle, spinal level (C3-T1), sex, age, body mass index (BMI).
Variable | Reference categorya | Estimate (95% CI) | Std Error | P |
|---|---|---|---|---|
Group | Asymptomatic | 17.01 (-32.85 to 66.87) | 25.10 | 0.500 |
Side (left) | Right | -13.62 (-19.96 to -7.28) | 3.23 | < 0.001 |
Muscle (levator scapulae) | SCMc | -149.86 (-166.76 to -132.97) | 8.62 | < 0.001 |
Muscle (multifidus)b | SCM | 217.24 (199.61 to 234.87) | 9.00 | < 0.001 |
Muscle (semispinalis capitis) | SCM | -505.37 (-522.26 to -488.48) | 8.62 | < 0.001 |
Muscle (splenius capitis)b | SCM | -357.89 (-374.78 to 341.00) | 8.62 | < 0.001 |
Muscle (longus colli) | SCM | -840.89 (-857.80 to -823.99) | 8.63 | < 0.001 |
Spinal level (C4) | C3 | 7.77 (-3.40 to 18.93) | 5.70 | 0.173 |
Spinal level (C5) | C3 | 23.08 (11.80 to 34.36) | 5.76 | < 0.001 |
Spinal level (C6) | C3 | 40.42 (29.20 to 51.65) | 5.73 | < 0.001 |
Spinal level (C7) | C3 | -19.97 (-31.04 to -8.89) | 5.65 | < 0.001 |
Spinal level (T1) | C3 | -257.28 (-268.09 to -246.46) | 5.52 | < 0.001 |
Sex (Female) | Male | -293.55 (-343.88 to -243.21) | 25.27 | < 0.001 |
Age | – | -2.21 (-4.68 to 0.25) | 1.24 | 0.078 |
BMI | – | 8.75 (3.13 to 14.36) | 2.82 | 0.003 |
Muscle (levator scapulae)*group(pain) | SCM/asymptomatic | -57.78 (-79.83 to -35.73) | 11.25 | < 0.001 |
Muscle (multifidus)*group(pain) | SCM/asymptomatic | 59.79 (36.86 to 82.73) | 11.70 | < 0.001 |
Muscle (semispinalis capitis)*group(pain) | SCM/asymptomatic | 21.77 (-0.28 to 43.82) | 11.25 | 0.053 |
Muscle (splenius capitis)*group(pain) | SCM/asymptomatic | -39.12 (-61.17 to -17.07) | 11.25 | 0.001 |
Muscle (longus colli)*group(pain) | SCM/asymptomatic | 6.51 (-15.55 to 28.58) | 11.27 | 0.563 |