The type of approach does not influence TKA component position in revision total knee arthroplasty — A clinical study using 3D-CT

Abstract Background The influence of the surgical approach on the position of the prosthetic components in revision of total knee arthroplasties (rTKA) is still not clear. This study compared the medial parapatellar approach (MPA) and lateral parapatellar subvastus approach with tibial tubercle osteotomy (LPA). Methods Forty-two consecutive patients underwent rTKA from 2006 to 2016 with either MPA (n = 21) or LPA (n = 21) because of aseptic loosening, infection, malposition or instability (mean follow-up: 41.5 months). Revision TKA component position and leg alignment were assessed on three-dimensional CT (3D-CT) images and compared between groups using a t-test (p  2 -test (p  Results Group MPA and LPA showed no significant differences with respect to the femoral component (coronal: 0.6° vs 0.9°; sagittal: 7.5° vs 7.7°; transversal: 0.4° vs − 0.2°), tibial component (coronal: 0.1° vs 0.3°; sagittal: 3.1° vs 1.6°; transversal: 6.9° vs 9.3°) and leg alignment (varus: 0.2° vs 1.1°) (p  Conclusions In contrast with primary TKA, the two approaches did not influence postoperative rTKA position. This can be explained with the more extensive approach at rTKA and means that no corrections of the orientation of the components are needed performing either MPA or LPA.