80 porcine deep flexor tendons were harvested from adult porcine forelimbs and randomized into four groups of twenty tendons. Three groups were repaired using either a two, four or six strand repair, and the remaining group was repaired with the new device. Half of each group was repaired using a core technique alone; the remainders were supplemented with a Silfverskiöld Peripheral Cross Stitch. The repairs were pre-loaded to 1N in a Zwick Linear Tensiometer, with subsequent distraction to failure at 10mm/min. When preloaded the tendon dimensions were measured at the repair site as well as above and below in order to assess repair site bulk. During loading the Force to Produce 3mm Gap (FPG) was recorded as was the Ultimate Strength (US) following failure.
The FPG of the new device was superior to the Cruciate when used alone and was equivalent to the Savage when augmented with a peripheral repair. The US of the new device was superior to the Cruciate both with and without a peripheral repair.
We plan to continue development of the device to optimize its hold on the tendon. We also plan to perform cyclical testing in physiological conditions
Biomechanical testing was performed with a Zwig tensinometer using a one neuton preload and a distraction rate of 20mm/min. Bulking was measured with a digital micrometer and each repair group was tested for mean load to repair failure and mean load to 2mm gap formation. In each case the mechanism of failure was recorded.