Abstract:[Objective] To compare the clinical outcomes of conservative therapy versus surgical treatment of acute patellar dislocation in adolescents. [Methods] A retrospective study was performed on 40 adolescent patients who received treatment for acute patellar disloca- tion in our department from 2014 to 2018. The patients were divided into two groups according to whether intraarticular loose bodies noted by imaging examination. Of them, 23 patients without intraarticular loose bodies were given conservative therapy, while the other 17 pa- tients with intraarticular loose bodies were given surgical repair of medial patellofemoral ligament (MPFL) . The documents regarding earlystage, follow-up and imaging consequences were compared between the two groups. [Results] In the conservative group, all the 23 patients had no adverse reactions and complications during treatment. In the operation group, all the 17 patients were successfully operated on with- out serious complications such as vascular and nerve injury. Patients in both groups were followed up for 3~7 years, with an average of (4.8± 1.1) years. During the follow-up, 1 patient in the conservative group and 1 patient in the surgery group reoccurred patella dislocation, with- out a significant difference in the redislocation rate between the two groups (P>0.05) . Compared with those pre-treatment, the Kujala and Lysholm scores, as well as the knee extension and flexion range of motion (ROM) significantly increased in both groups at 6 months after treatment and at the last follow-up (P<0.05) . However, there were no significant differences in terms of Kujala score, Lysholm score and knee extension and flexion ROM between the two groups at any corresponding time points (P>0.05) . Regarding imaging, the patellar title (PT) and patellar displacement (PD) significantly reduced in both groups at latest follow-up compared with those preoperatively (P<0.05) . Although there was no significant difference in PT and PD between the two groups before treatment (P>0.05) , the conservative group had significantly greater PT and PD than the surgical group at the latest folloe-up (P<0.05) . [Conclusion] Both conservative therapy and surgi- cal repair achieve satisfactory and comparable clinical outcomes for acute patellar dislocation in adolescents. An individualized treatment plan should be made according to the concrete condition of the patient.