Itoh M, Itou J, Kuwashima U, et al. - This study was sought to present good validity and high internal consistency of the forgotten joint score-12 in patients after medial opening wedge high tibial osteotomy. Researchers excluded individuals with bilateral knee surgery, previous knee surgery, flexion contracture >15°, varus alignment >20°, and patients without plate removal surgery. They examined 71knees of 71 patients, with a mean follow-up of 34.5 months. They obtained Forgotten Joint Score-12 (FJS-12) score and the Knee Injury and Osteoarthritis Outcome Score, and the floor and ceiling effect of each score was evaluated. The data exhibited that in patients following medial opening wedge high tibial osteotomy (MOWHTO), FJS-12 displayed a lower ceiling effect than Knee Injury and Osteoarthritis Outcome Score and high internal consistency and convergent validity. As per the findings, FJS-12 was found to be beneficial for assessing patients following MOWHTO, with its low ceiling effect.