Comparison of short-term radiographic outcomes of medial parapatellar, mini-midvastus, and subvastus surgical approaches in fast-track total knee arthroplasty

Purpose: Due to the difficulties in accessing the knee joint, correct prosthesis placement is of great importance during the implementation of total knee arthroplasty (TKA). This study aimed to compare short-term radiographic X-ray outcomes in patients who underwent fast-track TKA with medial parapatellar (MPP), mini-midvastus (mMV), or subvastus (SV) surgical approaches. Materials and methods: Between 2018 and 2020, 93 patients operated with MPP, mMV, and SV surgical approaches and who had complete data of radiographic outcomes before and sixth-week postoperative were retrospectively analyzed and patients divided into three groups: MPP (n=31), mMV (n=31), and SV (n=31). The alignments of preoperative and sixth-week postoperative X-ray images of the surgical approaches were measured. The operative time of fast-track TKA implementation with MPP, mMV, and SV surgical approaches was recorded. Results: The MPP group had higher preoperative lateral distal femoral angle than the mMV group and a higher preoperative lateral proximal femoral angle than SV group (p=0.018 and p=0.027, respectively). The mMV group had higher postoperative proximal medial tibial angle than SV group (p=0.011). In the postoperative sixth week, the MPP and mMV groups had a lower posterior tibial slope angle than SV group (p=0.001). The MPP approach had significantly shorter operative time than mMV and SV approaches (p=0.001). Conclusion: The outcomes indicate that MPP, mMV, and SV surgical approaches are preferable and feasible in obtaining a satisfactory prosthesis alignment during fast-track TKA. The MPP approach may be preferable because of its shorter operative time and potential advantage in minimizing surgical complication risks.