Risk factors for coracoclavicular reconstruction failure: a systematic review.

Background: The coracoclavicular (CC) ligament reconstruction for acromioclavicular injuries is performed through a variety of surgical techniques and fixation methods. The purpose of this study is to determine the risk factors associated with failure of CC reconstruction, regardless of the fixation method used. Methods: A systematic review was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Medline, Embase, and Cochrane were searched through November 2024 for studies analyzing the failures of CC reconstructive surgery. Studies that quantified risk factors for CC reconstruction failure were included. Results: Seven studies comprising 781 CC reconstructions were analyzed with an overall failure rate of 19.1%. Clavicle tunnel malposition in anatomic reconstructions was the most cited risk factor for failure. Position was defined as either the distance from the lateral aspect of the clavicle to the tunnels or as a ratio between this distance and the length of the clavicle. Three studies cited increased failure risk with medial malposition of the conoid or trapezoid tunnels. Specific parameters included conoid tunnel ratio >0.25, (odds ratio (OR) = 5.67), trapezoid ratio >0.15 (OR = 4.2), conoid tunnel >47 mm (OR = 4.67), and trapezoid tunnel >24 mm (OR = 4.2). Lateral conoid tunnel malposition with a conoid tunnel ratio <0.20 (OR = 40) was also noted to increase failure risk. Another study identified increased risk of failure when surgeons use tunnel ratios instead of tunnel distance in mm intraoperatively (OR = 4.609). Placement of a lateral coracoid button, as opposed to a central button, was cited in 2 studies as significant risk factors (OR = 9.614, 13.87). Other risk factors included osteoporosis (OR = 8.652), weight-bearing before 6 weeks from surgery (OR = 6.4), surgery >6 weeks from initial injury (OR = 2.65), osteolysis (OR = 4.386), patient age >40 (OR = 3.14), and open reconstruction (OR = 4.25). Conclusions: Conoid and trapezoid tunnel malposition, both medially and laterally, were significantly associated with an increased risk of failure. Additionally, patient age, osteoporosis, osteolysis, time to weight bearing after surgery, delayed presentation of more than 6 weeks from initial injury, should be considered when considering surgical intervention.