Improving the biomechanical properties of the T-fix using oblique direction: in vitro study on bovine menisci

This study compared pullout strengths of the T-fix device versus horizontal suture toward improving T-fix biomechanical properties. Twenty bovine medial menisci were used for this study. Four groups were tested and mean tearing stress were obtained. In group 1 a standard T-fix suture was performed (50.2+/-4.2 N); in group 2 horizontal mattress sutures were placed in the meniscus using 2-0 vicryl (54.6+/-4.2 N); in group 3 three T-fix suture anchors were placed: the central suture a double suture anchor and those on either side single suture anchors, resulting in two horizontal sutures (61.8+/-3.8 N); in group 4 we modified the technique used in group 3. The double suture anchor was placed the incision, at a 30 degrees angle oblique to the horizontal (71.0+/-5.9 N). There was a statistically significant difference between groups 3 and 4 but not between groups 1 and 2.

Using a T-fix suture anchor in the standard technique has similar biomechanical properties to the horizontal mattress suture. To improve the tensile properties of the T-fix suture a double T-fix suture anchor should be used obliquely to the other two single T-fix sutures on either side.