Initial failure strength of open and arthroscopic Bankart repairs

Surgical repair of recurrent anterior shoulder instability requires secure fixation of the separated inferior glenohumeral complex to bone. Many techniques of fixation are in use for both arthroscopic and open repair. The specific aim of this study was to compare the initial failure strength of eight repair techniques using a previously described canine model of Bankart repair. Intact capsule-to-bone complexes failed at the bony interface at 236 N. Traditional Bankart repair failed at 122.1 N (2 sutures) and 74.7 N (1 suture), Acufex TAG rod (Acufex Microsurgical, Mansfield, MA) at 143.5 N (2 sutures) and 79.8 N (1 suture), transglenoid suture technique (2 sutures) at 166.6 N, Mitek GII (Mitek, Norwood, MA) (1 suture) at 96.4 N, Zimmer Statak (Zimmer Inc, Warsaw, IN)(1 suture) at 95.2 N, and Acufex bioasbsorpable Suretac at 82.2 N. The two-suture repairs were statistically equivalent in strength to each other, as were the one-suture repairs and the Suretac device. Two-suture repairs were significantly stronger than the one-suture repairs (P < .01) failure. In the single-suture specimens, failure occurred by suture breakage in 46% (18 of 39) of specimens and soft-tissue failure around the suture in 54% (21 of 39). Failure in the two-suture techniques primarily occurred by soft-tissue failure (23 of 25) and this proved a statistically significant difference (P < .003). No device broke or pulled out of bone.