Aim: to analyze the advantages and disadvantages of using unicompartmental and total knee replacement in case of medial knee osteoarthritis, to determine the existing differential criteria for choosing the method of arthroplasty, taking into account the individual patient’s risk factors. Results. Analysis of data from the modern literature did not allow to determine clear differential criteria for choosing the optimal method of arthroplasty in medial knee osteoarthritis, taking into account the individual patient’s risk factors. Unicompartmental knee replacement is associated with better functional outcomes, lower incidence of complications, faster recovery, and greater patient satisfaction. In addition, there are no convincing claims of a statistically significant difference in the frequency of revisions or longevity of implants, which have long been considered significant benefits of total knee replacement. Conclusion. Due to the improvement of surgical techniques and greater availability in the choice of implants, unicompartmental knee replacement has proven to be an effective method of treatment of isolated medial knee osteoarthritis.