OBJECTIVE We aimed to evaluate the results and complications of open reduction and internal fixation by locked anatomic plates in adult midshaft clavicular fractures. METHODS Sixteen patients (11 males, 5 females; mean age: 39.6 years) who underwent open reduction and internal fixation with locked anatomic plate for displaced-comminuted midshaft clavicular fractures and were followed-up for at least one year were reviewed retrospectively. Complications in the early and late postoperative periods and functional scores according to the Constant and DASH scoring systems from the latest follow-up were evaluated. RESULTS Mean follow-up period was 24.6 (range: 12 to 52) months and mean union time was 13.3 (range: 10 to 23) weeks. None of the patients had superficial and/or deep infections in the early postoperative period or neurovascular complications. Two (12.5%) patients had implant irritation. In two (12.5%) patients, implant failure was detected in the late postoperative period. Delayed union was suspected in these patients and they were operated with longer plate and grafting in the 4th month. At the final follow-up, none of the patients had nonunion or malunion and the mean Constant and DASH scores were 85.5 and 12.8, respectively. Constant scores in patients with complications (p=0.007) and DASH scores in patients with no complications (p=0.001) were significantly lower. CONCLUSION Fixation with locked anatomic plates in displaced midshaft clavicular fractures has lower complication rates. Possible postoperative complications are generally associated with implant irritation and failure. These problems can be avoided with the development in implant technology and new implant designs.