Collagen-platelet composite enhances biomechanical and histologic healing of the porcine anterior cruciate ligament

Am J Sports Med. 2009 Dec;37(12):2401-10. doi: 10.1177/0363546509339915.


Background: The anterior cruciate ligament (ACL) fails to heal after traumatic rupture. Furthermore, large-animal models have recently shown that 1-month functional ACL healing is augmented after suture repair when a bioactive scaffold is placed in the tear site.

Hypothesis: At the time of suture repair, placement of a bioactive scaffold in the ACL wound site would improve the structural properties of the tissue.

Study design: Controlled laboratory study.

Methods: Twenty-seven knees in immature pigs underwent ACL transection and suture repair. A collagen-platelet composite (CPC) was used to supplement the repair in 14 knees. Knees were harvested at 4 weeks, 6 weeks, and 3 months. Mechanical testing and histologic analysis were performed.

Results: The addition of a CPC to a suture repair resulted in improvements in yield load and linear stiffness of the repair tissue at 3 months, as well as a significant increase in cell density. A reduction in yield load and stiffness occurred at the 6-week time point in both groups, a phase when revascularization was noted.

Conclusion: The addition of a CPC to a suture repair enhanced the structural properties of the ACL, and the improvement was associated with increased cellularity within the healing ligament.

Clinical relevance: The addition of a bioactive scaffold to the wound site improved the functional healing of the ACL after suture repair. The decreased repair strength during revascularization may indicate a need to protect the repair site through this period.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Anterior Cruciate Ligament / surgery*
  • Anterior Cruciate Ligament / transplantation
  • Biomechanical Phenomena
  • Blood Platelets
  • Collagen / therapeutic use*
  • Models, Animal
  • Platelet Transfusion*
  • Random Allocation
  • Sus scrofa / surgery
  • Tissue Scaffolds
  • Treatment Outcome
  • Wound Healing / physiology*


  • Collagen