Tension level during preconditioning influences hamstring tendon graft properties

John J. Elias, Srianjana Kilambi, William J. Ciccone

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Background: Hamstring tendon grafts used for anterior cruciate ligament reconstruction are preconditioned to reduce the influence of viscoelasticity on the stiffness and tension. Hypothesis: Increasing the tension applied during preconditioning will decrease the loss of tension and stiffness due to viscoelasticity. Study Design: Controlled laboratory study. Methods: Six quadruple-strand hamstring tendon grafts were tested twice in vitro with 2 tension levels applied during preconditioning. The grafts were preconditioned at 80 N or 160 N, followed by 15 minutes of relaxation, and subsequently loaded to 80 N to represent application of initial tension. After 5 minutes of relaxation, the tension was recorded and the stiffness was measured over 0.06 mm of displacement. The tension and stiffness measurements were repeated 3 hours later. The data were compared between the 2 preconditioning levels with a 2-way repeated-measures analysis of variance. Results: Graft tension and stiffness were significantly larger (P < .05) for 160 N during preconditioning. For 80 N, the average tension at 5 minutes and 3 hours was 40 N and 21 N, respectively, compared with 50 N and 30 N, respectively, for 160 N. For 80 N, the average stiffness at 5 minutes and 3 hours was 152 N/mm and 124 N/mm, respectively, compared with 173 N/mm and 146 N/mm, respectively, for 160 N. Conclusion: Increasing the tension applied to hamstring tendon grafts during preconditioning can decrease the postoperative loss of tension and stiffness due to viscoelasticity. Clinical Relevance: The increased graft tension and stiffness could reduce postoperative knee laxity.

Original languageEnglish (US)
Pages (from-to)334-338
Number of pages5
JournalAmerican Journal of Sports Medicine
Issue number2
StatePublished - Feb 2009
Externally publishedYes


  • ACL reconstruction
  • Hamstring tendon graft
  • Initial tension
  • Preconditioning

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation


Dive into the research topics of 'Tension level during preconditioning influences hamstring tendon graft properties'. Together they form a unique fingerprint.

Cite this