Minimally Invasive Total Knee Arthroplasty

Abstract

Minimally invasive total knee arthroplasty (MIS TKA) was first reported in 2003 by Tria and Coon. Seventy MIS TKAs with a subvastus approach were completed over 9 months. They reported 50% less blood loss, and 20% more range of motion at first OPD visit. The alignment of the prosthetic components was the same as those from standard total knee arthroplasty (S TKA). Most reports in the literature later showed higher Knee Society scores, greater flexion, earlier straight leg raising in MIS TKA in short term follow up, but also more complications and poorer component alignment. The results of a systematic review and meta-analyses were similar although the number of cases was limited.Most of the reports on MIS-TKA are from surgeons with much experience in traditional S TKA. Even for these skilled surgeons there is a significant learning curve. Thus, it may not be appropriate for all surgeons to lightly adopt the MIS TKA technique and expect similar results. MIS TKA for some particular surgeons, however, may provide more advantages than disadvantages. The ultimate goal for MIS TKA is a painless, well functioning knee with good longevity. As proper alignment of prosthetic components is the key to achieving this goal, MIS TKA should not compromise component alignment. A gradual transition from traditional S TKA to MIS TKA with selected patients is recommended. Even a high-volume, experienced surgeon should perform MIS TKA only in selected cases after appropriate discussion with patients about the advantages and disadvantages of this approach.