Coronal curvature of tibial leads to malalignment of tibial prosthesis after total knee arthroplasty / 中国骨伤

ABSTRACT

OBJECTIVE@#To investigate the effect of tibial coronal curvature on the alignment of tibial prosthesis in patients undergoing total knee arthroplasty (TKA).@*METHODS@#From July 2019 to April 2021, 100 patients with knee osteoarthritis were treated with total knee arthroplasty. Before operation, the full-length films of lower limbs were taken and the tibial bowing angle(TBA) was measured. TBA more than 2° was tibial bending, which was divided into tibial bending group and non bending group. There were 40 cases in tibial bending group, 9 males and 31 females, aged 56 to 84 years old with an average of (69.22±7.10) years. There were 60 cases in the non bending group, 19 males and 41 females, aged from 51 to 87 years old with an average of (70.80±7.21) years. The preoperative tibial length (TL) and medial proximal tibial angle (MPTA) were measured and compared between the two groups. The full-length X-rays of the lower limbs were taken again 3 days to 1 week after operation. The medial angle of the tibial component coronal aligement angle (TCCA) and the outilier rate of force line of the tibial prosthesis were measured and compared between the two groups. Pearson method was used to analyze the correlation between TCCA and age, TCCA and height, TCCA and weight, TCCA and BMI, TCCA and TBA, TCCA and TL, TCCA and MPTA; Spearman method was used to analyze the correlation between TCCA and gender, TCCA and Kellgren-Lawrence(K-L) grade.@*RESULTS@#All 100 patients successfully completed the operation and obtained satisfactory full-length X-rays in standing position. There was no significant difference in TL, MPTA and TCCA between bending group and non bending group(P>0.05). The outilier rate of force line in tibial bending group was 22.5%, and that in non bending group was 6.67%, the difference was statistically significant(P<0.05). The correlation study found that TCCA was strongly correlated with TBA(r=-0.702, P<0.01), weakly correlated with MPTA(r=0.311, P<0.01), and had no correlation with other parameters(P>0.05).@*CONCLUSION@#In patients with knee osteoarthritis undergoing total knee arthroplasty, tibial bending will lead to poor force line of tibial prosthesis. During operation, attention should be paid to osteotomy of proximal tibial vertical tibial mechanical axis and correct installation of prosthesis to avoid poor alignment of prosthesis.