Table 1.
Risk factors for Intra-operative fracture
| Risk Factors | Intra-operative Fracture (n = 71) | No Fracture (n = 489) | Uni-ANOVA | Multi-Regression Analysis | |||||
|---|---|---|---|---|---|---|---|---|---|
| OR | Chi2 | F (p) | OR | Chi2 | 95%CI | CST | |||
| Age (yrs +/-sd) | 83 +/- 6.7 | 81 +/- 7.5 | - | 0.906 | 0.66, p = 0.91 | 1.5 | 0.135 | 0.004 (0.001-0.008) |
0.98 |
| Sex (Female %) | 81.7% | 82% | 1.09 (0.57-2.08) |
0.707 | 0.30, p = 0.81 | 0.05 | 0.933 | 0.002 (0.08-0.893) |
0.93 |
| Time to operation (Days +/- SEM) | 1 +/- 3.3 | 1 +/- 3.3 | - | 0.328 | 0.07, p = 0.7 |
0.8 | 0.875 | 0.005 (0.001-0.001) |
0.99 |
| Operator experience (Median, yrs +/- SEM) | 8.31 +/- 6.9 | 7.7 +/- 6.3 | - | 0.455 | 0.44, p = 0.7 |
0.8 | 0.453 | 0.002 (0.003-0.007) |
0.99 |
| Cemented | 9 (12.7%) | 144 | 3.62* (1.61-8.10) |
0.001* | 11.7* , P < 0.001 | 3.4* | 0.001* | 0.133 (0.056-0.211) |
0.98* |
| Uncemented | 62 (87.3%)* | 345 | |||||||
OR = Odds Ratio. F = Uni-ANOVA statistic. P < 0.05 * considered significant.
CST = Colinearity Statistical Tolerance: (0-1). The higher the value, the less likely a Type I error has been committed.
The table confirms that only the Uncemented stems are a risk factor for intra-operative fracture