Biomechanical test comparing the load to failure of the biodegradable meniscus arrow versus meniscal suture

The biodegradable Meniscus Arrow (Bionx, Blue Bell, PA) is a newly introduced method for repair of meniscal injury. However, because of a lack of studies, there is still little understanding of its biomechanical behavior. Biomechanical test was carried out to evaluate the load to failure and failure modes of the Meniscus Arrow and to compare the results with those of three traditionally used methods. Thirty-five lateral menisci obtained from Yorkshire pigs were incised longitudinally, simulating a peripheral longitudinal tear, and were repaired by means of Meniscus Arrows (one-point and two-point fixation), as well as with the techniques of knot-end, horizontal, and vertical suture using No. I PDS II monofilament suture. Tensile strength testing was performed according to each repair method with the Instron tensometer (Model No. 5569; Instron, Canton, MA) and its results were analyzed using a computerized statistical program. The average maximal tensile strengths were 113.9 +/- 14.6 N in vertical suture, 75.1 +/- 18.4 N in horizontal suture, 53.9 +/- 6.4 N in knot-end suture, 38.3 +/- 4.3 N in one-point fixation Meniscus Arrow repair, and 56.5 +/- 3.5 N in two-point fixation Meniscus Arrow repair. The initial failure strength for two-point fixation Meniscus Arrow repair is comparable to that of a knot-end suture. Following the results of this study, meticulous caution should be taken when meniscal tears are repaired with Meniscus Arrows.