TWISTING OF PATELLAR TENDON GRAFTS DOES NOT REDUCE THEIR MECHANICAL-PROPERTIES

The purpose of this study was to investigate whether the twisting of a patellar tendon (PT) graft improves or reduces its mechanical propert ies. Twenty-seven pairs of 10 mm cadaveric PT grafts were tested at a strain rate of 10% min(-1). For each pair, the left specimen served as an unmanipulated control while the right specimen was either left unt wisted, twisted + 90 degrees, or twisted - 90 degrees. All avulsion fa ilures were excluded from the data analysis, focusing only on pure in- substance tendon ruptures. Higher ultimate load values than previously reported were obtained for both the twisted and untwisted specimens, without a statistical significant difference between the two. The valu es obtained for the left and right specimens from Group A were 4014 +/ - 319 and 3973 +/- 245 N, from Group B 3613 +/- 207 and 3891 +/- 14 N, and from Group C 3997 +/- 278 and 4415 +/- 507 N, respectively. Stiff ness and failure strain were not influenced by the twisting. Neither t he presence of a twist, nor the direction of the twist were found to i ncrease the ultimate load of the 10 mm cadaveric patellar tendon graft . Therefore, recommendation for twisting cannot be assessed to its mec hanical properties. (C) 1998 Elsevier Science Ltd. All rights reserved .