Title:
Arthroscopically assisted stabilization of chronic AC-joint instabilities in GraftRope™ technique with an additive horizontal tendon augmentation.

Abstract:
A chronic symptomatic acromioclavicular joint (ACJ) instability is a possible consequence of an acute ACJ separation. Besides vertical instability a horizontal component of the instability is common in high-grade ACJ separation and clinically relevant; especially, in chronic cases. A new technique of horizontal biologic ACJ augmentation with a transacromial gracilis tendon loop as an addition to the arthroscopically assisted stabilization with the GraftRope™ device is described and first clinical and sonographical results are shown.
The results after arthroscopically assisted single bundle reconstruction of the coracoclavicular (CC) ligaments with an additional horizontal tendon augmentation are comparable to the results of other stabilizing techniques in chronic ACJ instabilities.
A consecutive series of 20 patients with chronic symptomatic ACJ instability was stabilized with this new technique. 16 patients were followed-up clinically and sonographically. Patient satisfaction, visual analogue scale (VAS), simple shoulder test (SST), Constant score (CS) and Taft score (TS) were assessed. Bilateral sonographic measurements were performed to evaluate recurrent instabilities. Complications and concomitant glenohumeral injuries were analyzed.
Sixteen patients (n = 2 female, n = 14 male, median age 40 (21-61) years, follow-up rate 84 %) were evaluated median 13 months (range 4-27 months) after indexed operation. 11 patients had a chronic ACJ instability after Rockwood type III, and 5 patients after Rockwood type V lesion. 6 patients suffered a recurrent symptomatic instability after operative treatment. 10 patients of the group were primary stabilized with the new technique. 15 of 16 patients were satisfied with the result of the operation at the follow-up examination. The VAS was median 4.6 of 10 points (range 1.1-7.4 points). The SST reached 9 points (range 5-12 points). The adjusted CS was median 84 % (range 46-93 %) and TS median 9 points (range 5-12 points). The sonographic measurements showed a significant difference in the CC distance between the unaffected and the affected side (21.7 vs. 24.8 mm, p = 0.009). The acromioclavicular distance was median 11 mm (range 7-17 mm) after resection of the lateral clavicle. Concomitant glenohumeral injuries were arthroscopically detected in seven patients. Postoperative complications occurred in one patient (wound infection). In one case, the clavicular washer was removed due to local paresthesia after healing of the graft.
The arthroscopically assisted stabilization of chronic ACJ instabilities with the GraftRope™ device and an additive horizontal tendon augmentation technique leads to good short-term results with a supplementary horizontal stabilization.