Three-Dimensional Femoral Notch Volume in Anterior Cruciate Ligament-Deficient Versus Anterior Cruciate Ligament-Intact Patients: A Matched Case-Control Study With Inter-gender Comparison.

PURPOSE

The purpose of this study was to evaluate between-gender differences in 3-dimensional femoral notch volume in anterior cruciate ligament (ACL)-deficient patients compared with a matched control group of ACL-intact patients.

METHODS

Magnetic resonance images from 90 ACL-deficient patients (45 male and 45 female patients) aged 16 to 50 years were identified from our departmental database and then compared with a matched control group of ACL-intact patients. The 3-dimensional femoral notch volume on each magnetic resonance imaging study was measured using software-specific tools. One-way analysis of variance was used to compare notch volume between the ACL-deficient and ACL-intact groups and between the 2 genders. The relations between height, weight, body mass index, and notch volume for each group and within the male and female cohorts were established using Pearson product moment correlations.

RESULTS

The mean femoral notch volume in the female ACL-deficient group was 3.1 ± 0.70 cm(3) (95% confidence interval [CI], ± 0.2 cm(3)) compared with 3.6 ± 0.7 cm(3) (95% CI, ± 0.2 cm(3)) in the female control group. The mean femoral notch volume in the male ACL-deficient group was 4.5 ± 1.1 cm(3) (95% CI, ± 0.3 cm(3)) compared with 5.3 ± 1.2 cm(3) (95% CI, ± 0.4 cm(3)) in the male control group. There were significant differences between the male ACL-deficient and ACL-intact groups (P = .02), between the female ACL-deficient and ACL-intact groups (P = .0002), between the male and female ACL-deficient groups (P < .0001), and between the male and female ACL-intact groups (P < .0001). There were nonsignificant relations (r = 0.01 to 0.37) between height, weight, body mass index, and notch volume between groups and within the male and female cohorts.

CONCLUSIONS

These results show a decreased femoral notch volume as measured on 3-dimensional magnetic resonance imaging in ACL-deficient patients. There were significant differences in femoral notch volume between the male and female cohorts, as well as between ACL-deficient and ACL-intact patients of both genders. In the female cohort there was a 14% reduction in volume between the ACL-deficient and ACL-intact patients; in the male cohort there was a 15% corresponding reduction in volume. There was a 31% reduction in volume between genders in ACL-deficient patients, with female patients having a smaller volume than male patients. There was a corresponding 32% reduction in volume between genders in ACL-intact patients.

LEVEL OF EVIDENCE

Level III, case-control study.