2015 ISAKOS Biennial Congress ePoster #305

Preparation of Round Tendons to Flat Tendon. Does the Preparation Process Have Any Influence on the Structural Properties?

Mirco Herbort, MD, Prof., Muenster GERMANY
Christian Hoser, MD, Innsbruck AUSTRIA
Christoph Domnick, MD, Muenster GERMANY
Simon Lenschow, MD, Muenster GERMANY
Michael J. Raschke, Prof., Muenster GERMANY
Christian Fink, MD, Prof., Innsbruck AUSTRIA

Clinic for Trauma Surgery, Universitiy of Muenster, Muenster, GERMANY

FDA Status Not Applicable

Summary: Flat prepared tendons with original round shape do not have different structural properties in comparison to the round shaped tendons



Several surgical procedures require the use of tendineous support in order to replace or augment ruptured or chronically insufficient tissue.
Very often the hamstring tendons are used for these reconstructions. But the reconstructed structures are often thin and flat shaped like the MPFL or the MCL.
For anatomical reconstruction a graft with anatomical flat shape would be preferable.
Therefore an easy procedure for spliting of the round grafts and producing a flat tendon graft has been developed.


of this study was to evaluate the structural properties of porcine tendons after converting them into a flat shape and to compare these properties with the original round shaped tendons.
We hypothesized that the splitting procedure does not have any influence on the structural properties of the tendons.

In this biomechanical study we used porcine flexor tendons with the comparable shape of Semitendinosus (ST) and Gracilis tendons (G).
In porcine tendons one part of the tendons has been prepared to a flat tendon. Therefore the tendon has been splited with a knife half the diameter of the tendon. After that the tendon has been scratched out getting a flat shape (FT). The other part of the tendon has been tested in original shape(RT).
The tendons have been fixed in a uniaxial testing machine (Zwick Roell Z005) 2 cm at each side in a cryo clamp after preparing the fixed ends by 2 Ethibond suture. In every specimen there was a free 6 cm tendon part between both clamps which has been loaded.
The tendons have been loaded to failure to evaluate stiffness, yield load and maximum load.
For statistical analysis a Kruskal-Wallis test test has been used. The significance was set at p<0.05.

Biomechanical testing of the porcine tendons showed the following results:
Semitendinosus diameter:
Stiffness: 283.94 N/mm(+/-35.28) (RT) vs. 277.29 N/mm(+/-50.49) (FT)
Yield load: 1629,25 N (+/-272.92) (RT) vs. 1601.25 N (+/-368.72) (FT)
Maximum load: 1838.93 N (+/-210.05) (RT) vs. 1601.25 (+/-368.72) (FT)

Gracilis diameter:
Stiffness: 152.11 N/mm (+/-16.63) (RT) vs. 151.68 N/mm(+/-18.73) (FT)
Yield load: 872.89 N (+/-142.89) (RT) vs. 859.89 N (+/-118.41) (FT)
Maximum load: 983.74 N (+/-115.23) (RT) vs. 949.49 (+/-118.31) (FT)

There were no statistical differences found in compared parameters between round and flat tendons in both diameters. (p>0.05)

The results of the present study support our initial hypothesis. The prepared flat shaped tendons do not show different structural properties than the original tendons.
Therefore the prepared flat tendon seems to be a biomechanical stable graft with unchanged structural properties for reconstruction of flat structures.