TABLE 3.
Associations Between Baseline Patient Characteristics and Treatment Outcome
| SIJ Fusion | Nonsurgical Management | |||||
| VAS SIJ | ODI | EQ-TTO | VAS SIJ | ODI | EQ-TTO | |
| Age quartile | ||||||
| 1 (<24 yrs) | Ref | Ref | Ref | Ref | Ref | Ref |
| 2 (42–50) | −2.3 (0.5135) | 1.92 (0.4643) | −0.0294 (0.4219) | 5.5 (0.2976) | 5.3 (0.1374) | −0.001 (0.9905) |
| 3 (50–59) | −4.7 (0.1750) | 0.17 (0.9482) | −0.0231 (0.5210) | 5.8 (0.3026) | −0.6 (0.8725) | −0.041 (0.6536) |
| 4 (>59) | −9.1 (0.0080) | −1.39 (0.5921) | 0.0013 (0.9707) | 2.4 (0.6745) | 1.4 (0.6940) | 0.026 (0.7664) |
| Pain duration quartile | ||||||
| 1 (<1.5 yrs) | Ref | Ref | Ref | Ref | Ref | Ref |
| 2 (1.5–3) | −4.9 (0.1677) | 0.88 (0.7417) | 0.057 (0.1147) | 0.74 (0.8831) | 1.2 (0.7237) | −0.103 (0.2037) |
| 3 (3–6) | −7.7 (0.0282) | −0.19 (0.9431) | 0.067 (0.0644) | 3.42 (0.5048) | −1.5 (0.6693) | −0.082 (0.3234) |
| 4 (>6) | −5.2 (0.1384) | −0.26 (0.9235) | 0.105 (0.0035) | 1.50 (0.7872) | −3.9 (0.2969) | −0.101 (0.2619) |
| Current smoker | 5.9 (0.0299) | 4.4 (0.0292) | 0.0027 (0.9232) | −4.9 (0.3028) | −1.2 (0.7189) | 0.112 (0.1423) |
| Male gender | −1.3 (0.6324) | −2.4 (0.2453) | −0.029 (0.3111) | 3.1 (0.4344) | −0.52 (0.8493) | −0.030 (0.6418) |
| Bilateral SIJF | 2.1 (0.5172) | 1.5 (0.5484) | 0.027 (0.4155) | — | — | — |
| History of lumbar fusion | 3.0 (0.2236) | 1.6 (0.3868) | −0.027 (0.2841) | 1.9 (0.6403) | 0.17 (0.9501) | 0.044 (0.4959) |
| Opioids at baseline | 6.4 (0.0166) | 6.1 (0.0029) | −0.025 (0.3656) | 5.1 (0.1922) | 2.2 (0.3970) | −0.042 (0.5001) |
Each entry shows the regression coefficient for the subgroup level for changes in SIJ pain, ODI, or EQ-5D TTO index for the SIJF group and NSM group separately. Negative values indicate a decrease. Associated P values are given in parentheses. Significant values (P < 0.05) are bolded.
EQ-TTO indicates EQ-5D Time Trade-off Index; ODI, Oswestry Disability Index; Ref, reference level; VAS SIJ, visual analog scale sacroiliac joint pain.