One hundred patients were treated nonoperatively for primary acute patellar dislocations, either by plaster cast (N = 60), by posterior splint (N = 17), or by patellar bandage or brace (N = 23). Follow-up examinations were performed at an average of 13 years later (range, 6 to 26 years). Overall, there were 0.17 redislocations per follow-up year; the redislocation frequencies per follow-up year for each patient group were 0.29, patellar bandages or braces; 0.12, plaster cast; and 0.08, posterior splint. In addition, there were fewer recurrences and subsequent problems (patellofemoral pain or subluxations) in the group treated with posterior splints compared with the two other treatment groups. The most marked restrictions of knee joint movements were seen in the patients treated with plaster casts. Subjective assessment of treatment, however, did not differ significantly between the groups. Patients were also evaluated in relation to the treatment of redislocations and management of subsequent problems (i.e., patellofemoral pain or subluxations). Patients who were treated operatively for their redislocations exhibited better outcomes than patients treated nonoperatively. In the patients who had subsequent problems, the operation did not relieve the symptoms.