Aim: The aim of this prospective randomised study is to compare the results after TKA using an MIS approach versus a standard approach. Methods: We compared 30 TKA using a mini-midvastus approach (MIS group) with 30 conventionelly performed TKA using a midvastus approach (control group). The Knee Society score (KSS), an activity score, the visual analogue scale, myoglobin and creatinine kinase as well as the blood loss were measured up to 12 weeks after surgery. Implant positioning was evaluated using the Knee Society Roentgenographic evaluation and scoring system. Results: Advantages of the MIS group were measured in KSS and activity score up to 12 weeks after surgery. The increase of myoglobin and creatinine kinase was lower in the MIS group up to 24 hours or 72 hours, respectively. No differences were found comparing the implant positioning and blood loss. Conclusion: The MIS technique in TKA with minimisation of the soft tissue trauma leads to better clinical and functional results in the early postoperative time and does not modify the implant positioning.