TABLE 3.
Absolute ACL and MCL Strains by Sex With 1-Way Analysis of Variancea
| n | Raw | Normalized to Baseline | |||
|---|---|---|---|---|---|
| Mean ± SD, % | P | Mean ± SD, % | P | ||
| Maximum ACL strain | .184 | .077 | |||
| Male | 19 | 13.2 ± 8.1 | 7.6 ± 3.3 | ||
| Female | 20 | 16.7 ± 8.3 | 11.5 ± 8.7 | ||
| Maximum MCL strain | .311 | .157 | |||
| Male | 19 | 7.1 ± 5.8 | 6.1 ± 5.7 | ||
| Female | 20 | 5.4 ± 4.6 | 3.9 ± 3.2 | ||
| 00_00_00 | |||||
| Maximum ACL strain | .230 | .204 | |||
| Male | 19 | 6.9 ± 7.6 | 4.0 ± 4.4 | ||
| Female | 14 | 10.3 ± 8.0 | 6.8 ± 8.0 | ||
| Maximum MCL strain | .326 | .795 | |||
| Male | 19 | 1.7 ± 1.3 | 1.1 ± 1.1 | ||
| Female | 14 | 2.6 ± 3.4 | 1.2 ± 1.3 | ||
| ACL strain at IC | .736 | .221 | |||
| Male | 19 | 3.0 ± 5.5 | 0.0 ± 0.0 | ||
| Female | 14 | 3.5 ± 3.2 | 0.0 ± 0.0 | ||
| ACL strain at 33 ms | .552 | .119 | |||
| Male | 19 | 3.2 ± 5.9 | 0.2 ± 0.6 | ||
| Female | 14 | 4.2 ± 3.1 | 0.7 ± 1.2 | ||
| ACL strain at 66 ms | .224 | .175 | |||
| Male | 19 | 6.2 ± 7.5 | 3.2 ± 3.8 | ||
| Female | 14 | 9.4 ± 7.2 | 5.9 ± 7.1 | ||
| ACL strain at 100 ms | .323 | .368 | |||
| Male | 19 | 4.8 ± 5.8 | 1.8 ± 3.7 | ||
| Female | 14 | 6.9 ± 5.8 | 3.4 ± 5.8 | ||
| 67_67_67 | |||||
| Maximum ACL strain | .170 | .136 | |||
| Male | 19 | 7.7 ± 6.2 | 4.7 ± 3.6 | ||
| Female | 16 | 11.0 ± 7.7 | 7.6 ± 7.2 | ||
| Maximum MCL strain | .304 | .741 | |||
| Male | 19 | 2.4 ± 2.0 | 2.1 ± 1.9 | ||
| Female | 16 | 3.6 ± 4.4 | 2.3 ± 2.5 | ||
| ACL strain at IC | .176 | .056 | |||
| Male | 19 | 3.3 ± 4.3 | 0.3 ± 0.5 | ||
| Female | 16 | 5.6 ± 5.6 | 2.2 ± 4.1 | ||
| ACL strain at 33 ms | .177 | .054 | |||
| Male | 19 | 3.6 ± 4.9 | 0.7 ± 1.1 | ||
| Female | 16 | 6.1 ± 5.6 | 2.7 ± 4.2 | ||
| ACL strain at 66 ms | .123 | .079 | |||
| Male | 19 | 6.0 ± 6.8 | 3.0 ± 3.7 | ||
| Female | 16 | 9.8 ± 7.4 | 6.4 ± 7.1 | ||
| ACL strain at 100 ms | .146 | .106 | |||
| Male | 19 | 5.0 ± 4.8 | 2.0 ± 2.5 | ||
| Female | 16 | 7.8 ± 6.3 | 4.4 ± 5.5 | ||
| Prefailure | |||||
| Maximum ACL strain | .214 | .213 | |||
| Male | 19 | 12.0 ± 7.9 | 7.7 ± 3.4 | ||
| Female | 19 | 15.2 ± 7.6 | 10.3 ± 8.3 | ||
| Maximum MCL strain | .713 | .167 | |||
| Male | 19 | 5.1 ± 4.0 | 4.3 ± 3.3 | ||
| Female | 19 | 4.6 ± 4.3 | 2.9 ± 2.7 | ||
| ACL strain at IC | .700 | .874 | |||
| Male | 19 | 6.8 ± 5.9 | 2.6 ± 2.4 | ||
| Female | 19 | 7.5 ± 5.2 | 2.7 ± 3.1 | ||
| ACL strain at 33 ms | .636 | .723 | |||
| Male | 19 | 7.3 ± 6.3 | 3.1 ± 1.9 | ||
| Female | 19 | 8.2 ± 4.8 | 3.4 ± 3.2 | ||
| ACL strain at 66 ms | .228 | .214 | |||
| Male | 19 | 10.4 ± 8.4 | 6.1 ± 3.8 | ||
| Female | 19 | 13.6 ± 7.7 | 8.7 ± 8.3 | ||
| ACL strain at 100 ms | .328 | .331 | |||
| Male | 19 | 9.8 ± 7.3 | 5.5 ± 3.0 | ||
| Female | 19 | 12.0 ± 6.7 | 7.2 ± 6.9 | ||
aBecause all tests were randomized, n values may differ from the original value (n = 39) as some tests were not able to be performed before knee ligament damage. Because maximum MCL strain lacked demonstrable sex differences in the controlled external load conditions (ie, 00_00_00, 67_67_67, and prefailure), the MCL time values were excluded. ACL, anterior cruciate ligament; IC, initial contact; MCL, medial collateral ligament.