Symptomatic Nonunion of the Coracoid Process Following Osteosynthesis Using a Suture Button for Coracoid Process and Distal Clavicle Fracture: A Case Report

BACKGROUND Coracoid process fractures are uncommon and are often complicated by many types of shoulder girdle injuries. Previous reports have shown that osteosynthesis for isolated coracoid process fractures results in favorable outcomes and high bone union rates. However, owing to the rarity of coracoid process fractures combined with distal clavicle fractures, there are limited data to guide treatment strategies. We report a case of symptomatic nonunion despite performing osteosynthesis for fractures of the coracoid process and distal clavicle. CASE REPORT A 60-year-old man presented with left shoulder pain after falling from the back of a truck. Radiography and computed tomography (CT) findings revealed fractures of the left distal clavicle and coracoid process. We performed plate and costoclavicular fixation using a suture button for the distal clavicle fracture and cannulated cancellous screw fixation for the coracoid process fracture. However, the patient experienced severe pain around the coracoid and had limited shoulder range of motion 1 year postoperatively. CT revealed nonunion of the coracoid process, prompting a recommendation for surgery. However, despite severe persistent functional impairment, the patient refused surgery 1.5 years postoperatively. CONCLUSIONS This case suggests the potential for symptomatic nonunion of the coracoid process when using a suture-button device for a distal clavicle fracture. To prevent postoperative nonunion of the coracoid process, postoperative CT evaluation is necessary. If a symptomatic delayed bone union of coracoid process is observed, considering early removal of the suture button is recommended.