Table 4.
Univariable Cox regression with four different follow-up times for players with ACLR (n = 112)
| Follow-up times, months | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0–12 | 0–24 | 0–36 | 0–>36 | |||||||||
| Second ACL injury, n (%) | 17 (15) | 28 (25) | 35 (31) | 43 (38) | ||||||||
| 95% CI | 95% CI | 95% CI | 95% CI | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HR | Lower | Upper | HR | Lower | Upper | HR | Lower | Upper | HR | Lower | Upper | |
| 1. Time between injury and ACLR, months | 0.916 | 0.785 | 1.069 | 0.893 | 0.785 | 1.014 | 0.903 | 0.809 | 1.008 | 0.898 | 0.812 | 0.992 |
| Cut-off < 7.1 months (n = 85) | 2.875 | 1.131 | 7.307 | |||||||||
| 2. Level of play after primary ACLR, n (%) | ||||||||||||
| Elite (2 top divisions) | 1.432 | 0.239 | 8.570 | 1.190 | 0.320 | 4.434 | 1.662 | 0.487 | 5.679 | |||
| Third–sixth division | 1.762 | 0.415 | 7.473 | 0.999 | 0.349 | 2.863 | 1.176 | 0.415 | 3.331 | |||
| Lowest division or youth play, referencea | ||||||||||||
| 3. IKDC (0–100) | 1.031 | 0.980 | 1.084 | 1.008 | 0.974 | 1.043 | 1.004 | 0.974 | 1.035 | 1.002 | 0.976 | 1.030 |
| 4. ACL-RSI (0–10) | 1.154 | 0.878 | 1.516 | 1.002 | 0.818 | 1.228 | 1.001 | 0.834 | 1.201 | 1.017 | 0.862 | 1.199 |
| 5. ACL-QoL (0–10) | 1.252 | 0.845 | 1.855 | 1.051 | 0.794 | 1.392 | 1.031 | 0.802 | 1.324 | 1.009 | 0.805 | 1.264 |
| 6. SMPS—personal standards (1–5) | 0.908 | 0.558 | 1.478 | 1.270 | 0.854 | 1.888 | 1.176 | 0.830 | 1.666 | 1.211 | 0.882 | 1.661 |
| 7. SSP—somatic anxiety (0–100) | 1.027 | 0.973 | 1.085 | 1.017 | 0.974 | 1.061 | 1.014 | 0.977 | 1.054 | 1.023 | 0.989 | 1.058 |
| 8. SSP—psychic anxiety (0–100) | 1.013 | 0.966 | 1.061 | 1.013 | 0.977 | 1.051 | 1.015 | 0.983 | 1.049 | 1.018 | 0.989 | 1.049 |
| 9. SSP—stress susceptibility (0–100) | 1.031 | 0.987 | 1.078 | 1.023 | 0.988 | 1.059 | 1.016 | 0.984 | 1.048 | 1.024 | 0.996 | 1.053 |
| 10. SSP—impulsiveness (0–100) | 0.975 | 0.924 | 1.029 | 0.993 | 0.954 | 1.033 | 1.007 | 0.973 | 1.043 | 1.005 | 0.974 | 1.036 |
| 11. SSP—adventure seeking (0–100) | 0.959 | 0.902 | 1.020 | 0.979 | 0.935 | 1.026 | 0.993 | 0.954 | 1.034 | 0.982 | 0.947 | 1.019 |
| 12. Ankle dorsiflexion, side difference, degrees | 1.107 | 0.869 | 1.410 | 1.137 | 0.945 | 1.367 | 0.989 | 0.840 | 1.163 | 0.988 | 0.908 | 1.074 |
| 13. Knee extension ACLR leg, degreesb | 0.945 | 0.868 | 1.028 | 0.946 | 0.887 | 1.010 | 0.935 | 0.882 | 0.991 | 0.936 | 0.889 | 0.987 |
| Cut-off > −4 degrees (n = 39)b | 1.969 | 1.015 | 3.823 | 1.756 | 0.959 | 3.216 | ||||||
| 14. LSI—single hop for distance, % | 1.024 | 0.968 | 1.084 | 1.014 | 0.969 | 1.062 | 1.011 | 0.970 | 1.053 | 1.008 | 0.971 | 1.046 |
| 15. LSI—side hop, % | 1.014 | 0.989 | 1.039 | 1.014 | 0.995 | 1.034 | 1.008 | 0.991 | 1.025 | 1.013 | 0.997 | 1.028 |
| 16. 5-jump test, cm | 1.002 | 0.997 | 1.007 | 1.003 | 0.999 | 1.007 | 1.003 | 1.000 | 1.006 | 1.003 | 1.000 | 1.006 |
| 17. Tuck jumps total points (0–10) | 0.899 | 0.695 | 1.164 | 0.887 | 0.725 | 1.084 | 0.890 | 0.744 | 1.065 | 0.904 | 0.769 | 1.062 |
| 18. Knee collapse ACLR leg in DVJ, cm | 0.986 | 0.854 | 1.139 | 1.036 | 0.924 | 1.161 | 1.078 | 0.971 | 1.196 | 1.045 | 0.952 | 1.147 |
| 19. Knee collapse non-ACLR leg in DVJ, cm | 1.076 | 0.928 | 1.248 | 1.082 | 0.965 | 1.213 | 1.084 | 0.979 | 1.201 | 1.073 | 0.979 | 1.176 |
Values in bold type are statistically significant (P < . 05). ACL, anterior cruciate ligament; ACL-QoL, ACL-Quality of Life; ACLR, anterior cruciate ligament reconstruction; ACL-RSI, Anterior Cruciate Ligament -Return to Sport after Injury; CI, confidence interval; DVJ, drop vertical jump; HR, Hazard Ratio; IKDC, International Knee Documentation Committee Subjective Knee Form; LSI, Limb Symmetry Index; SMPS, Sport Multidimensional Perfectionism Scale; SSP, the Swedish Universities Scales of Personality
aNo events in the reference group for 12-month follow-up time
bKnee hyperextension values are negative and extension deficit values are positive