Morphology and asymmetry of the tibial plateau : Differences linked to the size of the epiphysis and to the sex

BACKGROUND : Asymmetric tibial base plate for total knee replacement would optimize the coverage of the tibial plateau and reduce the risk of overhang and conflict with the soft parts around the knee. Our work is a morphological analysis of the upper end of the tibia and the asymmetries wich exists between the medial and lateral compartment. METHODS : We carried out on the analysis of 150 MRIs of knee performed in our radiology department (90 men and 60 women (sex ratio: 3/2). Average age: 39.7 years old). The measurements performed were: tML, tMAP, tLAP, RCM, RCL, MBB and LBB. Also, we opted for the calculation and the comparison according to the gender of the following ratios: tMAP / tML, tLAP / tML, RCM / tML and RCL / tML.In order to characterize the asymmetry between the medial and lateral tibial condyles, we opted for the calculation of the following ratios: tLAP / tMAP; LBB / MBB and RCL / RCM. RESULTS : Our results demonstrated greater measurements in men with a structural differences for tMAP, tLAP, RCM. However, thess differences was more related to the size of the epiphysis for RCL, MBB, LBB. The asymmetry was more pronounced in women with tLAP / tMAP and did not vary with the size of the epiphysis. Size differences was less pronounced for RCL / RCM and LBB / MBB. CONCLUSION : These various elements could justify the interest of using an asymmetric tibial base to optimize coverage during knee replacements.