Biomechanical differences resulting from the combination of suture materials and repair techniques

Background. Many suture materials and repair techniques have been applied in clinical tendon surgery. However, no recommendation is available concerning the choice of suture materials and repair techniques except in a few experimental studies. The purpose of the current study is to show the biomechanical difference resulting from the combination of suture materials and repair techniques. Methods. The gastrocnemius tendons of 24-week-old cattle (diameter 14-16 x 9-11 mm) were repaired with application of a single locking, multiple locking, single grasping, or multiple grasping technique using a USP2 suture thread of either braided polyblend polyethylene, polyester, polydioxanone, or nylon. Therefore, a total of 16 combinations were made, with eight specimens for each combination. The specimen was set in an Instron tensiometer to measure the gap length after repetitive tensile loading 500 times (10-100 N). Results. The single locking technique using braided polyblend polyethylene provided the smallest gap (4.5 +/- 0.5 mm). Other techniques using the same material resulted in a large gap (10.0-11.8 mm). The polyester provided a relatively smaller gap length, irrespective of the repair technique (7.4-8.8 mm). Polydioxanone and nylon tended to result in a large gap (9.3-12.3 mm and 8.4-10.6 mm, respectively). Conclusions. Mechanical properties of each tendon suture depended on the particular combination of suture materials and repair techniques. The combination of braided polyblend polyethylene and single locking technique provided the highest antigap strength.