Morphometric study of gender difference in osteoarthritis posterior tibial slope using three-dimensional magnetic resonance imaging.

Posterior tibial slope (PTS) is an important parameter of sagittal alignment associated with postoperative stability and kinematics after total knee arthroplasty (TKA). However, data are limited regarding the innate gender differences in PTS in Koreans. The current study separately measured the PTS of the medial and lateral tibial plateau on magnetic resonance images of 511 patients with knee joint osteoarthritis who had Kellgren and Lawrence grade 3 and 4 (430 women, 81 men) and compared the measurements between and within the genders. The tibia was then rotated to the tibial plateau with the tibial centroid axis and the PTS was evaluated from best-fit planes on the surface of the proximal tibia and individually for the medial, lateral, and overall plateaus. The average overall PTS was 10.0° ± 3.5°. The average overall PTS of the female and male patients was 10.2° ± 3.4° and 8.8° ± 4.0°, respectively. The average medial PTS was 10.4° ± 4.0°, significantly greater than the mean lateral PTS of 8.7° ± 3.9° (P < 0.05). The average medial and lateral tibial slopes for female patients were 10.7° ± 3.8° and 8.8° ± 3.8°, respectively, while the average medial and lateral tibial slopes for male patients were 8.9° ± 4.8° and 7.9° ± 4.7°, respectively. The medial and overall PTS were significantly greater in female patients than in male patients (P < 0.05). The results showed a gender difference in PTS and that medial PTS was greater than lateral PTS. These findings have clinical relevance in knee reconstructive surgery for determining ideal placement of the posterior slope tibial component. Surgeons should be aware of variability and gender differences in the tibial slope of patients undergoing TKA.

Gender-related morphological differences in sulcus angle and condylar height for the femoral trochlea using magnetic resonance imaging.

PURPOSE: This study aimed to elucidate the primary differences in trochlear morphology between men and women utilizing three-dimensional magnetic resonance image reconstruction of the femoral trochlea. METHODS: Differences in anthropometric femoral trochlea data of 975 patients (825 women, 150 men) were evaluated. The following morphological parameters were measured at three flexion angles (15°, 30°, and 45°) of the femoral trochlea: the sulcus angle, condylar height, and the trochlear groove orientation and mediolateral groove position. RESULTS: The sulcus angle was significantly greater in women than in men at 15° and 45° flexions (P < 0.05). However, there was no gender difference found in the sulcus angle at 30° flexion. Medial and lateral condylar height values were greater in men than in women for the three flexion angles (P < 0.01). The trochlear groove orientation and mediolateral groove position showed no gender-related differences. CONCLUSIONS: Magnetic resonance image reconstruction demonstrated that measurement of trochlear morphology varied significantly between men and women. This study provides guidelines for the design of a suitable femoral component for total knee arthroplasty, considering gender-specific differences in the Korean population. Biomechanical guidelines for total knee arthroplasty in Korean individuals can be optimized using our finding, so as the risk of patellar dislocation to be decreased. Surgeons should be aware of gender differences in femoral trochlear to optimize choice of implant. LEVEL OF EVIDENCE: III.