Ex vivo evaluation of arthroscopically assisted shoulder stabilization in dogs using an intra-articular aiming device

Abstract

Objective: To evaluate the use of an intra-articular aiming device (IAD) for medial shoulder stabilization with a suture-toggle repair or an interference screw repair using bone anchors in dogs. Study design: Ex-vivo Study. Methods: Specimens were randomly divided into 2 groups (anchor and suture-toggle) with 10 shoulders each. Abduction angles were measured by goniometry prior to and following medial glenerohumeral ligament transection and after receiving arthroscopically assisted stabilization with either bone anchors or suture-toggle constructs. Bone stock and insertion angles were measured with computed tomography scans. All specimens were inspected by dissection. Results: Abduction angles increased post-transection in both groups, and were restored to normal in the anchor group, but 2° smaller than normal in the suture-toggle group following stabilization. Median magnitude of bone stock surrounding all tunnels ranged between 5.9 and 12.9 mm in the anchor group and 8.8 and 15.6 mm in the suture-toggle group (p =.002). Median insertion angles at the cranial glenoid, caudal glenoid, and humerus were 17.3°, 36.8 ° and 43.4° in the anchor group, respectively, and median insertion angles at the glenoid and humerus were 38.2° and 35.6° in the suture-toggle group, respectively (p =.91). Placement of anchors were not feasible in 3 specimens in the anchor group, and mild violations of the articular surfaces were detected in 3 specimens overall. Conclusion: Arthroscopically assisted shoulder stabilization with an IAD was feasible in canine cadavers. Clinical Significance: An IAD may facilitate arthroscopic shoulder stabilization in dogs. Further studies are warranted to evaluate safety and efficacy in a clinical setting.