Remodeling process and clinical outcomes following all-arthroscopic modified Eden-Hybinette procedure using iliac crest autograft and 1-tunnel double Endobutton fixation system

Abstract

Background: Arthroscopically modified Eden-Hybinette procedures for glenohumeral stabilization have been used for a long time. With the advancement of arthroscopic techniques and the development of sophisticated instruments, a double Endobutton fixation system has been used clinically to secure bone graft to the glenoid rim placed through a specifically designed guide. The purpose of this report was to evaluate clinical outcomes and serial glenoid remodeling process following all-arthroscopic anatomical glenoid reconstruction using autologous iliac crest bone grafting technique through 1-tunnel fixation.

Methods: Forty-six patients with recurrent anterior dislocations and significant glenoid defects greater than 20% underwent arthroscopic surgery with a modified Eden-Hybinette technique. Instead of firm fixation, autologous iliac bone graft was fixed to the glenoid by double Endobutton fixation system through 1-tunnel placed in the glenoid surface. Follow-up examinations were performed at 3, 6, 12, and 24 months. The patients were followed up for a minimum of two years using the Rowe score, the Constant score, the Subjective Shoulder Value, and the Walch-Duplay score; patient satisfaction with the procedure outcome was also rated. Graft positions, healing, and absorption were evaluated postoperatively with computed tomography imaging.

Results: At a mean follow-up of 28 months, all patients were satisfied and had a stable shoulder. The Constant score improved from 82.9 to 88.9 points (P ＜ .001), the Rowe score, improved from 25.3 to 89.1 points (P < .001), the Subjective Shoulder Value improved from 31% to 87% (P < .001), and the Walch-Duplay score improved from 52.5 to 85.7 points (P ＜ .001). One donor-site fracture occurred during the follow-up period. All grafts were well-positioned and achieved optimal bone healing with zero excessive absorption. The preoperative glenoid surface (72.6% ± 4.5%) increased significantly immediately after surgery to 116.5% ± 9.6% (P ＜ .001). After a physiological remodeling process, the glenoid surface remained significantly increased at the last follow-up (99.2% ± 7.1%) (P ＜ .001). The glenoid surface area appeared to decrease serially when compared between the first 6 months and 12 months postoperatively, while there was no significant interval change between 12 and 24 months postoperatively.

Conclusion: Patient outcomes were satisfactory following the all-arthroscopic modified Eden-Hybinette procedure using an autologous iliac crest grafting technique through one-tunnel fixation system with double Endobutton. Graft absorption mostly occurred on the edge and outside the ''best-fit'' circle of the glenoid. Glenoid remodeling occurred within the first year after all-arthroscopic glenoid reconstruction with an auto iliac bone graft.

Keywords: Arthroscopic; Endobutton fixation; anterior shoulder instability; bone defect; glenoid bone loss; modified Eden-Hybinette.