Acromioclavicular Joint Reduction, Repair and Reconstruction Using Metallic Buttons-Early Results and Complications

Acromioclavicular joint (ACJ) dislocation is a common injury often affecting young adults. Its sequalae range from an asymptomatic shoulder to one that is painful with significant loss of strength in the affected upper limb. The management of ACJ dislocation has revolved around expert neglect for asymptomatic low-grade dislocation to complex surgical reconstruction. The authors describe their early experience with a new technique to reduce and maintain reduction of the coracoclavicular interval using a low-profile doublemetallic button technique (Tightrope; Arthrex Inc, Naples, Fla). The fixation device comprises of a no. 5 Fibrewire suture that is tensioned and secured at both ends by metallic buttons against the cortices of the clavicle and the coracoid. The proposed advantages include a non rigid fixation of the AC joint that maintains reduction yet allowing for normal movement at the joint. The "snow shoe[hold on cortical bone means that the implant should withstand cyclic loading without cutting out from the bone. With these reasons, and because it is relatively low profile, there is no need for removal of implant. The authors have used this fixation technique on 8 patients. All the patients had strong intraoperative fixation. Immediate and 2-week postoperative radiographs demonstrated excellent reduction of the coracoclavicular interval and the AC joint. However, there were 4 patients with loss of reduction between 2 and 6 weeks postoperatively without additional injury. The mode of fixation failure is unclear at present. While the concept of metallic button fixation may have promise, the authors recommend further biomechanical assessment to evaluate potential weak link of the implant before its clinical use.