Thanase AriyawatkulChaturong PornrattanamaneewongRapeepat NarkbunnamKeerati ChareancholvanichMahidol University2018-11-092018-11-092014-01-01Journal of the Medical Association of Thailand. Vol.97, (2014), S34-S3801252208012522082-s2.0-84922246080https://repository.li.mahidol.ac.th/handle/20.500.14594/34359© 2014, Medical Association of Thailand. All Rights Reserved. Background: Medial opening wedge high tibial osteotomy (MOWHTO) is an effective treatment for varus osteoarthritic knee. Alteration of knee alignment after MOWHTO may affect ankle biomechanics. Objective: To evaluate the coronal alignment change of the ankle after MOWHTO. Material and Method: Thirty-five patients who underwent 40 MOWHTO procedures were retrospectively reviewed. Preoperative and 6 to 12 month postoperative standing hip-to-ankle films were assessed. Differences in the anatomical femorotibial angle (FTA) and the talar tilt angle (TTA) were measured and the correlations were analyzed. Results: The mean differences in FTA and TTA were 14.06±4.89 degrees and 0.48±1.27 degrees, respectively. Increased FTA difference was found to correlate with increased TTA (p<0.001). According to ROC analysis, an FTA correction of more than 14 degrees results in a 50% chance of altering ankle coronal alignment. Conclusion: An FTA correction of more than 14 degrees may alter ankle coronal alignment. Other factors may affect talar tilt; therefore, further study is required.Mahidol UniversityMedicineArticleSCOPUS