Coronal Alignment of the Lower Limb and the Incidence of Constitutional Varus Knee in Korean Females

Abstract

PurposeIn total knee arthroplasty (TKA), it is important to restore neutral mechanical alignment. The purpose of this study was to assess whether the lower limb alignment is neutral in healthy Korean females and investigate the incidence of constitutional varus knees among them.Materials and MethodsWeight-bearing full-leg standing radiographs were obtained from 118 healthy females between the ages of 20 to 39 years. One radiologist and two orthopaedic surgeons measured the hip-knee-ankle angle (HKAA), medial proximal tibial angle (MPTA), and femoral anatomic mechanical angle (FAMA) on the radiographs and compared with the traditional gold standard HKAA of 0°, MPTA of 3° varus, and FAMA of 6°.ResultsThe interobserver reliability of the three independent observers was high (p<0.001). The HKAA of the study subjects (1.35°±2.04°) was significantly different from the standard HKAA of 0° (p<0.001), but no statistically significant difference was observed in the MPTA (-3.18°±1.61°) and FAMA (5.99°±0.70°) from the standard values (p=0.083 and p=0.887, respectively). The incidence of constitutional varus alignment was 20.34%.ConclusionsIn Korean females, the mechanical axis of the lower limb was not neutral and the incidence of constitutional varus alignment was slightly higher than that in Western females. We believe that these findings should be taken into consideration in planning reconstructive surgery of the knee, such as TKA, unicompartmental knee arthroplasty, and high tibial osteotomy.

Balancing of total knee arthroplasty by bone cuts achieves accurately balanced soft tissues without the need for soft tissue releases

“…The postoperative coronal MA was similar to that reported for the normal Caucasian population9 and interestingly also for a normal female Korean population 12. Eighty-six per cent of our knees were within ±3° of neutral coronal MA, the so-called ‘ideal range’ aimed for with traditional MA techniques.…”

Comparison of Kinematic and Mechanical Alignment Techniques in Primary Total Knee Arthroplasty: A Meta-Analysis

“…[1,2] The standard surgical techniques for TKA use 2 different alignment methods for prosthesis implantation: mechanical alignment (MA) and kinematic alignment (KA). The MA technique aims to create a neutral lower limb axis by cutting the distal femur and proximal tibia perpendicular to the femoral and tibial mechanical axes and provides reliable longterm fixation and functional improvement.…”

Are Korean Patients Different from Other Ethnic Groups in Total Knee Arthroplasty?

“…In total knee arthroplasty (TKA), it has been the norm for orthopedic surgeons in Asia to utilize in their patients the same knee implants and surgical techniques designed for Western populations. Recently, however, there are increasing interests in the development of new implant designs and surgical approaches that can better accommodate Asian patients with lifestyles and anthropometric characteristics different from Western patients for, at least theoretically, more favorable clinical outcomes and higher satisfaction 1 2 3 4 5) . In this review, we will summarize physical characteristics of Korean patients such as relatively small stature/bone structure and high prevalence of varus deformity compared to Westerners 4 5 6) , and clinical studies concerning knee implants that allow for high flexion activities of squatting and kneeling.…”