Krackow Stitch and Whipstitch Use in Distal Biceps Tendon Rupture Repair: A Porcine Composite Bone Biomechanical Study

The suture combination of a Krackow stitch plus a whipstitch can be used to strengthen a tendon rupture repair. We compared biomechanical outcomes of suture repair techniques for distal biceps tendon ruptures using a single Krackow stitch with and without a whipstitch and a whip-stitch alone. Data were obtained from 36 thawed porcine flexor profundus tendons. A cortical button was secured to fourth-generation composite bone using No. 2 FiberWire (Arthrex) and No. 2 FiberLoop (Arthrex). The primary outcome was maximum load to failure. Secondary outcomes were displacement at the bone-tendon interface, total construct elongation, and stiffness. The Krackow plus whipstitch group (mean, 493.82 N; SD, 209.44 N) had a greater maximum load to failure as compared with the single Krackow group (mean, 333.71 N; SD, 172.32 N) (P=.01) and single whipstitch group (mean, 207.27 N; SD, 66.42 N) (P<.001). The single Krackow group (mean, 1.67 mm; SD, 0.89 mm) had a greater bone-tendon interface displacement (P=.01) after preloading and before cyclic loading than the single whipstitch group (mean, 0.83 mm; SD, 0.58 mm). There were no other secondary outcome differences between groups. A repair using Krackow plus whipstitch is biomechanically stronger with no difference in bone-tendon interface displacement, total construct elongation, or stiffness when compared with a single Krackow or single whipstitch. We recommend this repair technique for distal biceps tendon rupture repair, which may accelerate rehabilitation and decrease re-rupture rate. [Orthopedics. 2023;46(4):224-229.].