Session: 06-09-01: Musculoskeletal and Sports Biomechanics

Paper Number: 145168

145168 - Comparing the Whipstitch and Fibertag Tendon Suture Techniques: A Proposed Methodology 

The analysis of tendon repair suture techniques can help identify best practices for surgeons.  Currently, a gap exists in the understanding of the biomechanics and failure of tendon repair utilizing the Krackow stitch method as compared to the FiberTag implant.  The purpose of this project was to conduct experimental testing of both the Krackow stitch and FiberTag implant repair methods to determine the ultimate tensile strength of both methods, analyze the displacement of each repair method under cyclic loading, identify failure modes of each method, and compare the failure location of each repair method.

This study determined the biomechanical properties of the Krackow suture method and the FiberTag suture method in securing tendinous tissue during 1,000 cycles and compared the displacement and load to failure value for each suture method. Thirty, ten-centimeter bovine tendons, with a nine-millimeter diameter, were prepared for this protocol.  A group of 10 tendons were assigned to a different suture type: whip stitch, whip stitch with the FiberTag implant, and the Krackow stitch.  The whip stitch serves to validate the testing protocol against published experimental data.  This project utilized a Material Testing System (MTS) universal testing machine with a one kilonewton load cell for all iterations.  Specimens were secured with a hook through the suture on one end, and a clamp directly affixed to the tendon on the other end.   Specimens were then cyclically preloaded with a fluctuating axial load from 10N to 50N at 1 Hz for 10 cycles. Specimen were then loaded with a fluctuating axial load from 50 N to 250 N at 1 hz for 1,000 cycles, and then the specimen was loaded to failure at 2 mm/min.  Video was recorded for the entire duration of the test to identify failure modes, failure location, and any trends applicable to surgical repair of tendons.

Linear models evaluated each suture method for its displacement due to cyclic loading and its load to failure due to a set rate of displacement.  Recommendations will be made for tendon repair techniques. By understanding each suture method’s ultimate strength and displacement after cyclic loading, clinics can make more informed decisions on the optimal method for tendon repair.  Furthermore, analysis of failure modes and location of failure in each tendon repair method can help inform surgeons about possible improvements for future tendon repair techniques.  Additionally, this project can help inform recovery protocols and rehabilitation guidelines following tendon repair surgery by identifying failure modes.

Presenting Author: Madeline Clark United States Military Academy

Presenting Author Biography: Madeline Clark is a Junior at the United States Military Academy and is majoring in mechanical engineering.

Authors:

Madeline Clark United States Military Academy
Haley Kampert United States Military Academy
Brandon Clumpner United States Military Academy
Margaret Nowicki United States Military Academy
Michael Donohue Keller Army Community Hospital
Donald Colantonio Keller Army Community Hospital
Shawn Gee Keller Army Community Hospital