Anatomical Imaging Study on Uneven Settlement of the Proximal Tibia

Abstract

Objective Uneven settlement of the proximal tibia significantly contributes to the onset and progression of medial compartment knee OA; however, the specific location and variations of proximal tibial deformity remain unclear. Therefore, this study aimed to explore the effects of the anatomic morphology of different tibial regions on proximal tibial vara and proximal tibial microstructural changes with age in both sexes to reveal the pattern of uneven settlement of the proximal tibia. Methods In this retrospective study, we reviewed the radiographs of 414 patients (789 legs) between May and September 2021. The medial proximal tibial angle (MPTA) and four anatomic angles of the tibia (i.e., the tibial plateau‐epiphyseal line [PT‐EL] angle, epiphyseal line‐tibial platform [EL‐PF] angle, epiphyseal axis inclination angle [EAIA], and subepiphyseal axis inclination angle [SAIA]) were measured. The effect of each angle on MPTA and their changes with age in both sexes were investigated using Pearson's correlation coefficient and multiple linear regression. Results In females, PT‐EL angle, EL‐PF angle, and SAIA negatively correlated with MPTA (r = −0.325, −0.246, and −0.502; p 0.05). Conclusions Proximal tibial vara is affected by the anatomic morphology of the epiphyseal and subepiphyseal regions. In females, the uneven settlement of the epiphysis progresses with age and may be responsible for dynamic varus deformity of the proximal tibia.

Keywords

• Knee Osteoarthritis
• Proximal Tibial Vara
• Radiological Anatomy
• Uneven Settlement