Tool | Outcome Measure | Outcome Score, mean (95% CI) | Univariate Analysis | Multiple Linear Regression, β (95% CI), P value | |
No Spondylolisthesis (n = 154) | Spondylolisthesis (n = 54) | ||||
NDI | Pre | 37.0 (33.0, 41.0) | 42.0 (35.0, 50.0) | 0.210 | −4.928 (−15.271, 5.415), 0.344 |
Post | 29.7 (24.7, 34.7) | 25.7 (18.9, 32.5) | 0.377 | ||
Delta | −7.1 (−13.7, −0.6) | −13.6 (−23.0, −4.2) | 0.264 | ||
Paired samples t test | 0.033a | 0.007a | - | ||
PCS-12 | Pre | 35.0 (33.5, 36.5) | 34.1 (31.2, 37.0) | 0.568 | 1.990 (−1.674, 5.655), 0.285 |
Post | 37.8 (36.0, 39.6) | 39.3 (36.2, 42.4) | 0.544 | ||
Delta | 2.8 (0.9, 4.8) | 5.2 (1.4, 9.0) | 0.239 | ||
Paired samples t test | 0.005a | 0.008a | - | ||
MCS-12 | Pre | 48.0 (45.9, 50.0) | 44.1 (40.3, 47.9) | 0.044a | 4.841 (0.876, 8.805), 0.017a |
Post | 49.3 (47.3, 51.2) | 52.4 (49.4, 55.5) | 0.102 | ||
Delta | 1.3 (−1.0, 3.6) | 8.3 (3.8, 12.9) | 0.010a | ||
Paired samples t test | 0.258 | 0.001a | - | ||
VAS Neck | Pre | 5.6 (5.1, 6.0) | 6.3 (5.4, 7.2) | 0.116 | −1.077 (−2.568, 0.415), 0.154 |
Post | 3.5 (2.8, 4.1) | 2.9 (1.9, 3.9) | 0.377 | ||
Delta | −2.1 (−3.0, −1.1) | −3.3 (−4.9, −1.7) | 0.277 | ||
Paired samples t test | <0.001a | <0.001a | - | ||
VAS Arm | Pre | 5.5 (5.0, 6.1) | 6.2 (5.2, 7.2) | 0.136 | −1.206 (−2.954, 0.542), 0.172 |
Post | 3.1 (2.3, 3.9) | 3.0 (1.6, 4.4) | 0.740 | ||
Delta | −2.4 (−3.6, −1.3) | −3.5 (−5.6, −1.4) | 0.255 | ||
Paired samples t test | <0.001a | 0.003a | - |
Note: Univariate analysis: Mann-Whitney U, Pearson’s χ2, or Fisher’s Exact test.
Note: Multiple Linear Regression analysis conducted to predict whether presence of spondylolisthesis prior to surgery was a significant predictor of change in outcomes over time—controlling for factors including age, sex, BMI, smoking status, and baseline scores.
aIndicates significance (P < 0.05)
MCS-12, Mental Component Scores of the Short Form-12; NDI, Neck Disability Index; PCS-12, Physical Component Scores of the Short Form-12; VAS, visual analog scale.