Individualized rotational osteotomy of the posterior femoral condyle in total knee arthroplasty

CHEN Zhi-wei; TAN Jing; CUI Jun-cheng; DAI Zhu; FANG Yu-ji; CHEN Ye

doi:10.3969/j.issn.2095-252X.2018.04.003

Abstract：Objective To explore the effects of individualized posterior femoral rotational osteotomy on the femoral rotational alignment in total knee arthroplasty (TKA). Methods Forty-nine patients undergoing TKA surgery were randomly divided into two groups: Group A patients were planned according to preoperative CT measurements, and the osteotomy of the posterior femoral condyle was performed by adding the osteotomy block; Patients in Group B were referred to the posterior femoral condyle line (posterior femoral condyle axis, PCL) for external rotation of 3° osteotomy. CT scan data were imported into Carestream PACS software to measure the required block thickness, posterior and condylar angle (PCA) before and after the operation. The PCA absolute value of the femoral prosthesis, incidence of anterior knee pain and the KSS function score of the knee joint were compared after operation in 2 groups. Results All the forty-nine patients were followed up for 15 - 38 months, with an average of 26 months. The preoperative PCA or converted PCA values were (4.60 ± 1.06) degrees in Group A and (4.48 ± 1.33) degrees in Group B, without statistical significance (P ＞ 0.05). The absolute value of PCA or converted PCA value of the femoral prosthesis was (0.79 ± 0.42) degrees in Group A and (2.07 ± 0.85) degrees in Group B, with statistical significance (P ＜ 0.05). The incidence of anterior knee pain was 8.0％ in Group A and 20.8％ in Group B, with statistical significance (P ＜ 0.05). The knee joint KSS function score was (88.64 ± 7.54) points in Group A and (86.70 ± 8.24) points in Group B, without statistical significance (P ＞ 0.05). Conclusions According to preoperative CT scan data, individualized rotation osteotomy added with osteotomy block can effectively improve the accuracy of the femoral rotation alignment, and reduce the incidence of anterior knee pain. This method can be used to guide the femoral rotational alignment in TKA.