Anatomical Imaging Study on Uneven Settlement of the Proximal Tibia

• Published in: Orthopaedic surgery Vol. 15; no. 1; pp. 239 - 246
• Main Authors: Wang, Zhijie, Zheng, Yi, Meng, Decheng, Li, Handi, Ji, Chenni, Wang, Juan
• Format: Journal Article
• Language: English
• Published: Melbourne John Wiley & Sons Australia, Ltd 01.01.2023; John Wiley & Sons, Inc; Wiley
• Subjects: Age; Bones; Clinical; Female; Females; Humans; Knee; Knee Joint; Knee Osteoarthritis; Male; Males; Osteoarthritis; Osteoarthritis, Knee - diagnostic imaging; Patients; Proximal Tibial Vara; Radiography; Radiological Anatomy; Retrospective Studies; Sexes; Tibia - diagnostic imaging; Uneven Settlement; Knee Osteoarthritis; Uneven Settlement; Radiological Anatomy; Proximal Tibial Vara
• ISSN: 1757-7853; 1757-7861
• DOI: 10.1111/os.13632

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), and EAIA positively correlated with MPTA (r = 0.099, p < 0.05). Regression analysis showed that the correlations between MPTA and PT‐EL angle, EL‐PF angle, and SAIA were significant (β = −1.003, −0.013, and −0.971; adjusted R2 = 0.979). Furthermore, MPTA negatively correlated with age (r = −0.202, p < 0.05); PT‐EL angle and EAIA positively correlated with age (r = 0.237 and 0.142, p < 0.05). Regression analysis showed that only the correlation between PT‐EL angle and age was significant (β = 5.635, p < 0.05). In males, PT‐EL angle, EL‐PF angle, and SAIA negatively correlated with MPTA (r = −0.270, −0.267, and −0.533; p < 0.05), and EAIA positively correlated with MPTA (r = 0.135, p < 0.05). Regression analysis showed that the correlations between MPTA and PT‐EL angle, EL‐PF angle, and SAIA were significant (β = −0.992, −0.017, and −0.958; adjusted R2 = 0.970). However, there was no significant correlation between age and any of the measured angles (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. This study is the first to reveal the effect of the anatomic morphology of different regions of the tibia on proximal tibia vara and their changes with age in different genders, in order to reveal the pattern of the uneven settlement of the proximal tibia, thus providing a basis for further study on the pathological changes of the knee osteoarthritis with varus alignment.