Acromioclavicular joint dislocation is a common disease of orthopedics. It is difficult to immobilize after manual reduction and has a higher operation rate. The safety and efficacy of arthroscopic double-Endobutton with Fiberwire suture through tenuous bone tunnel in the treatment of acromioclavicular joint dislocation have been confirmed. However, a few patients still have complications such as iatrogenic fracture and reduction loss, which are related to the thick bone canals of coracoid process and clavicle, or the decreased bone strength due to repeated drilling processes.

To investigate the surgical method and clinical efficacy of arthroscopic double-Endobutton with Fiberwire suture through tenuous bone tunnel in the treatment of Rockwood type III-V acromioclavicular joint dislocations.

From June 2019 to June 2020, a total of 12 patients (9 males and 3 females) with acromioclavicular joint dislocations were admitted and treated. The ages ranged from 31 to 65 (41.7±2.5) years old. There were 3 left cases and 9 right cases. The time from injury to operation was 2 to 7 (4.2±1.7) days. Preoperative X-ray and CT scan showed complete dislocations of acromioclavicular joint. According to Rockwood classification, there were 8 type III cases, 1 type IV case and and 3 type V cases. All patients underwent arthroscopic reduction and double-Endobutton fixation with Fiberwire suture through tenuous bone tunnel, and received postoperative re-examinations including X-ray and 3D CT immediately after the operation and on the 1st day, 1st month, and 6th month after operation. All patients were assessed using the rating scale of American shoulder and elbow surgeons (ASES) , Constant score, visual analogue scale (VAS) and shoulder range of motion before operation, and 1 month, 3 months and 6 months after operation.

The ASES scores and Constant scores significantly increased in the 1st , 3rd and 6th months after operation compared with hose before operation, and there were statistical differences (P<0.05) . The VAS scores decreased significantly in the 1st , 3rd and 6th months after operation (P<0.05) . The ranges of motion of shoulder flexion and abduction significantly improved in the 1st, 3rd and 6th months after operation (P<0.05) . One month after surgery, the diameter of bone tunnel was (2.34±0.12) mm measured by 3D CT without reduction loss. At the last follow-up, the X-ray films and CT scans of all patients showed no reduction loss or fractures of coracoid process or clavicle. One patient had secondary frozen shoulder 2 months after operation which was relieved by injecting betamethasone into the glenohumeral joint.

The arthroscopic double-Endobutton with Fiberwire suture through tenuous bone tunnel in the treatment of Rockwood type III - V acromioclavicular joint dislocations has the advantages of minimal trauma, less bone loss of clavicle and coracoid process, and reliable reduction and fixation, and can potentially reduce the incidence of refracture and reduction loss.