Purpose: The purpose of this study was to report one year follow-up of clinical and economic results using minimally invasive versus standard techniques for primary TKA. A multi-surgeon, prospective study assessed the one year clinical and economic benefits of MIS versus standard approaches for primary TKA.

Method: Six surgeons, from September 2005 to January 2006, performed a total of 129 TKA cases with 63 patients in the MIS-SV group and 66 patients in the STD group. Data collected included demographic information with BMI, length of hospital stay, hospital cost, discharge disposition, rehabilitation outcomes and Knee Society Scores. Data was collected preoperatively, and at 10 days, six weeks, three months, six months and one year postoperatively

Results: Average LOS was significantly shorter (2.2 days) for MIS-SV group then 3.3 days for STD group. Preoperative range of motion was 1120 for both groups and improved to 1220 (MIS-SV) and 1230 (STD) at one year. Preoperative KSS Functional Scores were 44 for each and improved to 87.6 (MIS-SV) and 86.6 (STD) at one year. Preoperative KSS Knee Scores were 44 (MIS-SV) and 52 (STD). At one year post-operatively, the KSS Knee Score improved to 91.4 (MIS-SV) and 77 (STD). Economically, the MIS-SV procedures averaged $25,076±1,772 and the STD procedure’s mean was $29,928±6,587.

Conclusion: Clinically, no difference between MIS-SV TKA and STD TKA were observed in ROM and KSS Functional score at one year. MIS-SV TKA had a cost savings over STD TKA and KSS Knee Score was significantly better at one year for MIS-SV group