Chaurasia Aditi, Tyagi Ankita, Santoshi John A, Chaware Prashant, Rathinam Bertha A
Radiology, All India Institute of Medical Sciences, Bhopal, IND.
Anatomy, All India Institute of Medical Sciences, Bhopal, IND.
Cureus. 2021 Jan 25;13(1):e12907. doi: 10.7759/cureus.12907.
Background The asymmetric medial and lateral condyles of the distal femur and proximal tibia have a direct influence on the biomechanics of knee joint and prostheses design. This study aimed to determine the morphologic data, that is., anteroposterior (AP) and mediolateral (ML) widths, and the radius of curvature (ROC) of the geometric arcs of the distal femur and proximal tibia. Methods One hundred and seventeen adult dry bones (57 femurs and 60 tibias) were studied. Aspect ratios (AP/ML) were calculated. The AP and ML widths were measured using digital Vernier Caliper with a measuring range of 0-150 mm, resolution of 0.01 mm, and accuracy ± 0.02 mm. The geometric arcs of femoral and tibial condyles were divided into three parts namely anterior 1/3rd, distal (femur) or middle (tibia) 1/3rd and posterior 1/3rd and were estimated in the sagittal plane for the femur and transverse plane for tibia using the ROC gauges. Results For the femur, the mean AP length for medial and lateral condyles was 55.62 mm and 57.93 mm, respectively, while the mean ML width was 73.45 mm. For the tibia, the mean AP length for medial condyle (MC) and lateral condyle (LC) was 47.74 mm and 43.46 mm, respectively. The mean aspect ratios for the distal femur and proximal tibia were 1.26 and 1.45, respectively. The mean aspect ratios for MC and LC of the femur were 0.50 and 0.52, respectively, whereas, for tibia, they were 0.61 and 0.71, respectively. The mean ROC for femoral MC - 20.77 mm, 31.42 mm, and 19.68 mm and for LC - 21.48 mm, 64.40 mm and 19.06 mm for the anterior, distal and posterior arcs, respectively. The mean ROC for tibial MC - 22.42 mm, 22.49 mm and 19.94 mm, and LC - 19.92 mm, 21.79 mm and 20.95 mm for the anterior, middle and posterior arcs, respectively. Conclusions The morphologic data accumulated in this study for both the distal femur as well as the proximal tibia would provide guidelines and help the manufacturers of joint prostheses to address the potential for compromised implant fit and re-design and make available 'anatomic' knee prostheses appropriate for the local population which would not only improve function but also prolong the longevity of the prostheses.
背景 股骨远端和胫骨近端的内侧髁与外侧髁不对称，这对膝关节生物力学及假体设计有直接影响。本研究旨在确定股骨远端和胫骨近端的形态学数据，即前后径（AP）和内外侧径（ML）以及几何弧的曲率半径（ROC）。方法 对117块成人干燥骨（57块股骨和60块胫骨）进行研究。计算纵横比（AP/ML）。使用数字游标卡尺测量AP和ML宽度，该卡尺测量范围为0 - 150 mm，分辨率为0.01 mm，精度为±0.02 mm。股骨和胫骨髁的几何弧分为三部分，即前1/3、远端（股骨）或中间（胫骨）1/3以及后1/3，并分别在股骨矢状面和胫骨横断面使用ROC测量仪进行评估。结果 对于股骨，内侧髁和外侧髁的平均AP长度分别为55.62 mm和57.93 mm，而平均ML宽度为73.45 mm。对于胫骨，内侧髁（MC）和外侧髁（LC）的平均AP长度分别为47.74 mm和43.46 mm。股骨远端和胫骨近端的平均纵横比分别为1.26和1.45。股骨MC和LC的平均纵横比分别为0.50和0.52，而胫骨的分别为0.61和0.71。股骨MC前、远端和后弧的平均ROC分别为20.77 mm、31.42 mm和19.68 mm，LC的分别为21.48 mm、64.40 mm和19.06 mm。胫骨MC前、中、后弧的平均ROC分别为22.42 mm、22.49 mm和19.94 mm，LC的分别为19.92 mm、21.79 mm和20.95 mm。结论 本研究积累的股骨远端和胫骨近端的形态学数据将为关节假体制造商提供指导，有助于解决植入物适配性差的问题，并重新设计出适合当地人群的“解剖型”膝关节假体，这不仅能改善功能，还能延长假体使用寿命。
