Comparison of the Stability of Different Arthroscopic Tendon Fixation Techniques in Dynamic Tests

:  In studies concerning the stability of surgical tendon fixation techniques, a large variety of test configurations is found resulting in a broad scatter of results. The goal of this study was to establish a reliable test protocol for the investigation of the stability of repair techniques. At 88 fresh bovine shoulders, four different suture configurations were tested: simple stitches, mattress sutures, modified Mason-Allen configuration and double-row configuration. The difference in response to load cycles with native samples and that after repair was recorded. Bioresorbable anchors were used for tendon fixation, in a second run tendons were affixed to metal plates, and with a third run fixation stability was monitored with a video camera. The double-row technique was the most stable one with the lowest values of compliance at all selected levels of gap formation followed by the mattress suture configuration. The simple stitch configuration and the modified Mason-Allen techniques were the most compliant techniques. By establishing this test protocol, we achieved a very accurate method of measurement (accuracy of 2 μm) with as few external influences as possible. The great advantage is that the proposed protocol allows the measurement of the mechanical quality of the suture fixation without an external device such as calipers.