Morphometric measurements of knee joints using magnetic resonance imaging (MRI) scans

Abstract

Introduction: Most commercially available total knee arthroplasty implants are designed for western populations, which typically have larger build and stature compared to their Asian counterparts often resulting in mismatch between resected bony surfaces and implant components. There is paucity of morphometric data of distal femur and proximal tibia in a Nepalese population, hence this study was conducted.

Method: A prospective, cross sectional study was performed in knee MRI of patients attending Patan Academy of Health Sciences, Lalitpur, Nepal. One hundred and seventy digital knee MRI of patients fulfilling inclusion criteria were included in study. Different parameters were measured from distal femur and proximal tibia using RadiAnt DICOM viewer software. Student’s t-test was applied to assess whether there were significant gender differences in measured femoral and tibial parameters.

Result: The mean mediolateral and anteroposterior dimensions of distal femur were 7.39±0.71 cm and 4.94±0.48 cm respectively, whereas for proximal tibia, 6.94±0.64 cm and 4.56±0.48 cm respectively. The mean aspect ratio for femur was 1.50±0.11 and for tibia was 1.52±0.094. All measured morphometric parameters in distal femur and proximal tibia were found to be statistically significantly higher in males compared to females (p<0.001). However, there was no significant gender difference in tibial aspect ratio (p>0.05).

Conclusion: This study provides knee joint morphometric data to help orthopaedic surgeon in selecting appropriately sized prostheses for total knee arthroplasty. The findings also highlight significance of considering gender based anatomical variations during prosthesis design and selection.