A 120° Preoperative Knee Flexion Cutoff Identifies Patients Likely to Achieve Postoperative Flexion ≥ 120° and Clinically Meaningful Flexion Gain After Total Knee Arthroplasty. - Kubo, Mitsuhiko; Maeda, Tsutomu; Kumagai, Kosuke; Amano, Yasutaka; Nosaka, Yuki; Uenaka, Kazuhiro; Fujikawa, Hitomi; Horikawa, Sadafumi; Kawasaki, Taku; Imai, Shinji (Journal of Clinical Medicine, 2026)