Factors influencing clavicular tunnel widening after single bundle coracoclavicular ligament reconstruction

The coracoclavicular ligament reconstruction (CLR) technique for the treatment of acromioclavicular joint (ACJ) dislocation has gained immense clinical popularity. However, this technique also has some limitations including complications such as distal clavicle fractures, coracoid fractures, bone tunnel widening, implant failure, and loss of reduction. A study was conducted to analyse the extent of CTW after single-bundle CLR by measuring radiographic parameters to determine its relationship with clinical variables to reduce the risk of clavicular tunnel widening (CTW), thereby providing important insights for clinical practice.

This retrospective analysis was conducted at Affiliated Fuyang People's Hospital of Bengbu Medical University, and data from 96 patients who underwent single-bundle CLR for type III-VI ACJ dislocation between January 2018 and December 2023 were initially collected. Finally, 84 patients met the inclusion criteria (63 male and 21 female, mean age: 49.5 ± 12.36 years). The clavicle tunnel (CT) width and coracoclavicular distance (CCD) was measured immediately postoperatively and at 6 months follow up using radiographic imaging, and the degree of expansion at 6 months was recorded. Preoperative variables including patient sex, age, injury cause, injury side, body mass index (BMI), Rockwood classification, extent of the CCD after surgery, and the CT location were recorded to analyze their correlation with the extent of CTW at 6 months follow up.

With an average follow-up duration of 10 months (range: 6-18 months). Both the extent of the CCD and CTW measured at 6 months postoperatively were differently enlarged, compared to early postoperative period (EPO) (P < 0.05). The results showed that there were no statistically significant differences in the CTW at 6 months postoperatively with respect to patients' sex, causes of injury, sides of injury, and Rockwood classification types(P > 0.05). However, the location of CT was significantly associated with the extent of CTW at 6 months postoperatively (P < 0.05).

The location of CT drilling is a significant factor that affects tunnel widening. When the drilling site is situated closer to the conoid tubercle, the extent of CTW is greater than when the tunnel is located farther from the conoid tubercle.