Effects of braiding on tensile properties of four-strand human hamstring tendon grafts.
BACKGROUND
Anterior cruciate ligament reconstruction is commonly performed with autogenous hamstring tendon grafts.


OBJECTIVE
To ascertain the effects of braiding on ultimate tensile strength and stiffness of hamstring tendon graft.


METHODS
Controlled laboratory study.


METHODS
Sixteen fresh-frozen semitendinosus and gracilis tendons were harvested from eight matched (right and left) human cadaveric specimens. Both sets of hamstring tendons from each matched pair were doubled, creating a four-strand graft. Grafts were then randomized so that one graft from each matched pair was braided and the other remained unbraided. The diameter of each graft construct was recorded. Grafts were tested to failure on a materials testing machine.


RESULTS
There were no significant differences in cross-sectional area before or after braiding. Fifteen of 16 tendons failed midsubstance; 1 failed at the lower clamp. Braiding reduced the initial tensile strength and stiffness of human hamstring tendon grafts in this study by 35.0% and 45.8%, respectively.


CONCLUSIONS
Braiding may place the collagen fibers in a suboptimal orientation for loading that results in a weaker graft. We do not recommend the use of braiding if the strongest, stiffest initial graft is desired.
Millett
Peter J
PJ
Steadman Hawkins Sports Medicine Foundation, Vail, Colorado. Harvard Medical School, Brigham & Women's Hospital, Boston, Massachusetts 02115, USA.
Miller
Bruce S
BS
Close
Matthew
M
Sterett
William I
WI
Walsh
William
W
Hawkins
Richard J
RJ
D000368:Aged; D000369:Aged, 80 and over; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D002102:Cadaver; D003094:Collagen; D005260:Female; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures / Q000379:methods*; D011183:Postoperative Complications; D013710:Tendons / Q000033:anatomy & histology / Q000637:transplantation*; D013718:Tensile Strength; D016474:Weight-Bearing
D003094:Collagen