Fig. (1) A 72-year-old female patient with rheumatoid arthritis underwent minimally invasive total knee arthroplasty through the medial approach (A, B). The femorotibial angle was corrected from 162° to 174° (C, D), the knee range of motion improved from 120°/–20° to 125°/–5° for flexion and extension, respectively, and the Knee Society score improved from 45 to 84.