Background:Although the early clinical outcomes of total knee arthroplasty (TKA) using minimally invasive surgery techniques have been widely described,data on the mid-to long-term outcomes are limited.We designed a retrospective study to compare the two most common TKA techniques-The modified quadriceps-sparing (m-QS) approach and the mini-medial parapatellar (MMP) approach-In terms of the clinical and radiographic parameters,over a minimum follow-up period of 5 years.Methods:The m-QS approach was used in 31 knees and the MMP approach,in 36 knees.Knees in both groups were compared for component position and alignment,knee alignment,length of the skin incision,range of motion,Visual Analog Scale score,muscle torques,Knee Society Score,West Ontario and McMaster Universities Osteoarthritis Index,and number of complications.Results:There were no major intergroup differences in any of the clinical and radiographic outcomes assessed at the final follow-up examination.Conclusions:On the basis of numbers studied,the m-QS group,which requires more technique,showed equivalent results with the MMP group in the postoperative 5 years.Preservation of the extensor mechanism in the m-QS approach could not ensure any improvement in the clinical outcomes during the mid-term follow-up duration.