Table 4.
Association between the study participants’ characteristics and the SF-36 health-related quality of life scores 6 months after total knee arthroplasty (n = 138)
| SF-36 SCORE 6 MONTHS AFTER TKA † | β‡ | 95% CI | P value |
|---|---|---|---|
|
Physical functioning (R2 = 0.23) |
|
|
|
| SF-36 Physical functioning score before surgery (%) |
0.24 |
0.01 to 0.47 |
0.036 |
| Presence of contralateral knee pain before surgery§ |
- 12.68 |
- 20.37 to - 4.99 |
0.001 |
| Psychological distress (PSI score /42) |
- 0.54 |
- 1.06 to - 0.02 |
0.04 |
| Comorbidities (CIRS score / 56) |
- 2.60 |
−4.11 to - 1.08 |
<0.001 |
|
Role-physical (R2 = 0.17) |
|
|
|
| SF-36 Role-physical score before surgery (%) |
0.31 |
0.12 to 0.51 |
0.01 |
| Comorbidities (CIRS score /56) |
- 2.02 |
- 3.91 to - 0.13 |
0.04 |
| Number of in-hospital complications¶ |
−7.41 |
- 14.23 to - 0.69 |
0.03 |
|
Bodily Pain (R2 = 0.13) |
|
|
|
| SF-36 Bodily pain score before surgery (%) |
0.72 |
0.43 to 1.01 |
<0.001 |
| Presence of contralateral knee pain before surgery |
−7.45 |
−14.34 to - 0.55 |
0.03 |
| Comorbidities (CIRS score /56) |
- 1.97 |
- 3.37 to - 0.57 |
0.001 |
| Number of in-hospital complications¶ | −5.47 | - 10.52 to - 0.39 | 0.04 |
TKA: Total knee arthroplasty.
† Stepwise multiple regression analysis.
‡ Multivariate unstandardized linear regression coefficients. For each unit of the participants’ characteristics there is on average a β increase (+) or a decrease (−) on the SF-36 score. A positive β has a positive effect on the participants’ condition and a negative β has a negative effect.
SF-36 scores before surgery, psychological distress and comorbidities treated as continuous variables. Higher scores signify better patient status.
Other independent variables are categorical.
§ Presence compared to absence of contralateral knee pain as measured by the WOMAC pain scale.
¶ Reference category = 0 compared to 1 or ≥ 2 complications.