Bearing dislocation is a special complication of mobile-bearing unicompartmental arthroplasty, caused by many factors, such as imbalance of the flexion and extension gap, malposition of components, impingement by the remaining osteophytes and cement, damage or delayed chronic laxity of medial collateral ligament, traumatic accident and habitual high knee flexion. It can be reduced by strictly controlling the operation indications before operation, osteotomy and implanting the prosthesis accurately while protecting the medial collateral ligament during operation, actively guiding the appropriate rehabilitation actions and activity intensity of patients after operation. Treatment should be individualized according to the causes and individual conditions of patients.