The early results of gender-specific total knee arthroplasty in Thai patients.

We prospectively evaluated a consecutive series of 314 patients (265 females and 49 males) who underwent unilateral TKA and received an average of 2 years of follow-up. In all patients, a standard (STD) or a gender-specific (GS) femoral component was selected based on the presentation of intra-operative medio-lateral overhanging of the femoral cutting guide over the femoral condyle. There were no significant differences in the pre-operative parameters of both groups. At the last follow-up, both STD and GS groups had similarly improved KS clinical scores (92.9 vs. 92.1 points), function scores (89.5 vs. 89.7 points) and ROM (133.5° vs. 134.1°) with no difference in the rate of lateral retinacular release. The overall percentage of the GS component selection was 52.5% (165/314) and was significantly higher in female patients than male patients (60.8% vs. 8.2%, p<0.0001). In addition, selected GS prostheses increased significantly with increasing femoral size (25% for size C, 53% for size D, 86% for size E, and 100% for size F, respectively). There were no complications or early loosening related to the GS prosthesis. The mean post-operative limb alignment was 5.5° of the anatomical valgus with no difference between groups. We concluded that the GS femoral component did not provide better clinical outcomes than the standard femoral component; however, it provided surgical ease to minimize prosthesis overhanging in patients with narrow femoral condyles.