Table 2.
Unadjusted associations with re-operation
| Unadjusted OR (95% CI) | p-value | |
|---|---|---|
| Demographics | ||
| Age < 75 y.o. | 2.50 (1.45–4.35) | 0.001 |
| Medical comorbidities | ||
| Charlson Comorbidity Score | 0.88 (0.80–0.97) | 0.010 |
| Dementia | 0.22 (0.07–0.74) | 0.014 |
| Social history | ||
| Smoking | 2.58 (1.40–4.73) | 0.002 |
| Operation characteristics | ||
| Type of nail | ||
| Long Affixus nail | Ref. | Ref. |
| Long Gamma nail | 2.29 (1.33–3.97) | 0.003 |
| Radiographic measurements | ||
| Femoral neck shaft anglea | ||
| Normal | Ref. | Ref. |
| Coxa valga | 0.27 (0.12–0.62) | 0.002 |
| Coxa vara | 3.92 (1.30–11.83) | 0.015 |
| Number of fragments (comminution) | ||
| Simple | 1.49 (0.77–2.85) | 0.234 |
| Moderate | Ref. | Ref. |
| Severe | 2.29 (1.19–4.41) | 0.013 |
| Lateral cortex gap size (mm) | ||
| ≥ 4 | Ref. | Ref. |
| 5–9 | 2.64 (1.43–4.87) | 0.002 |
| ≥ 10 | 3.47 (1.62–7.41) | 0.001 |
| Posterior cortex gap size (mm) | ||
| ≤ 4 | Ref. | Ref. |
| 5–9 | 2.54 (1.34–4.83) | 0.004 |
| ≥ 10 | 3.77 (1.40–10.12) | 0.009 |
| Reduction angle groupedb (degrees) | ||
| Valgus 5–varus 5 | Ref. | Ref. |
| Valgus > 5 | 1.67 (0.51–5.41) | 0.397 |
| Varus 5–10 | 3.25 (1.69–6.24) | < 0.001 |
| Varus > 10 | 6.76 (2.49–18.37) | < 0.001 |
| Complications | ||
| Failure at lag screw junction | 2.39 (0.47–5.03) | < 0.001 |
| Self-dynamisation | 6.11 (2.38–15.63) | < 0.001 |
| Cut-out | 22.76 (2.69–192.52) | 0.004 |
| Non-union | 15.14 (8.01–28.63) | < 0.001 |
| Fracture-related infection | 17.85 (3.76–84.79) | < 0.001 |
| Massive transfusion | 7.32 (1.31–40.87) | 0.023 |
a Femoral neck shaft angle: measured in the opposite uninjured hip. In cases of bilateral fractures, measurements were taken from the radiographs closest to the date of injury
b Reduction angle: measured in the immediate post-operative period