Use of anthropometric data from the medial tibial and femoral condyles to design unicondylar knee prostheses in the Chinese population

Abstract

Anthropometric data on medial tibial condyles and medial femoral condyles of 172 normal knees (94 male knees, 78 female knees) were obtained using three-dimensional computer tomographic measurements. In the medial tibial condyle, we measured the anteroposterior (AP) and widest dimension (WD), and compared the measurements with the similar dimensions of five tibial unicondylar knee prostheses conventionally used in China. In the femur, we used best-fit two-circular arcs to measure the morphology of the sagittal plane of the medial femoral condyle. We found that three of the prostheses showed WD overhang for all ranges of the AP dimension, while two of them showed WD underhang. We also found a progressive decrease in the condylar aspect ratio (WD/AP%) in parallel with an increase in the AP dimension in the medial tibial condyle. However, none of the conventional tibial prosthesis showed a similar change. Furthermore, males had larger values in aspect ratio than females with the same values for AP dimension. There were definite correlations between the radius of the curvature for the posterior part (R1) and distal part (R2) in the sagittal plane of medial femoral condyle. Both of these values were smaller than in the Caucasian population. Both radiuses of curvature for the posterior and distal components showed definite correlations with the AP dimension. The results of this study may provide guidelines for designing unicondylar knee prostheses suitable for the Chinese population.

Are Western Knee Designs Dimensionally Correct for Korean Women? A Morphometric Study of Resected Femoral Surfaces during Primary Total Knee Arthroplasty

“…Previous studies radiographically measured the ML width and AP length to evaluate the morphology of the distal femur. 7 8 10 12 13 16 17) While these data provide information on the overall shape of the distal femur, they may not be suitable for femoral implant designs as radiographic dimensions will be different from the actual width and length after bone cutting in surgery. In agreement with previous studies, 6 8 11) all measurements of the distal femur were performed after the completion of all bone cuts and are thought to be more accurate and useful in designing implants.…”

“…The number of patients reported was small and measurements were limited to AP and ML dimensions, while the dimensions were measured from imaging inclusive of computed tomography (CT) and magnetic resonance imaging (MRI). 7 8 10 12 13) Direct measurements of the prepared bone surfaces will provide more accurate data. 6 9 14) …”

Effect of vertical cut on coronal coverage and rotation of tibial component in Oxford unicompartmental knee arthroplasty

“…Evidence indicates that the anteroposterior and mediolateral lengths of the tibial plateaus of Chinese people are generally smaller than those of Westerners, and the design parameters of the Oxford prosthesis mainly refer to the anthropometric data of Westerners, leading to a low anatomic match between the design of the tibial component and the characteristics of Asians. 17 , 18…”

Anthropometry of the medial femoral condyle in the Chinese population: the morphometric analysis to design unicomparmental knee component

“…It has the advantages of minimal trauma and rapid recovery, and the longterm and medium-term curative effects are satisfactory [1][2][3]. However, most UKA components currently used in China are designed for the physique of Western individuals, and many studies have shown that components designed for Western patients are not matched for other populations [4][5][6]. Although current studies have shown that UKA has good clinical results in Asian population [7][8][9], it is still worth considering to design more suitable UKA components for Chinese people.…”