gerFluck, Christian GerdNiethard, Fritz UweHybridstrukturen zum Tissue Engineering des vorderen Kreuzbandes : biomechanische Untersuchungeninfo:eu-repo/classification/ddc/610Ligamentum cruciatum anteriusTissue EngineeringBiologisch abbaubarer KunststoffMedizinanterior cruciate ligamenttissue engineerigbiodegradable polymerThe anterior cruciate ligament (ACL) exercises an important biomechanical function in the human knee joint. It stabilizes the joint partners Femur and Tibia against anterior translation and serves as a rotation stabilizer. Injuries of the ACL therefore lead first of all to instability in the knee joint and subsequently to secondary gonarthrosis. The annual incidence of rupture of the ACL is 80,000, with approximately 50,000 ACL-reconstructions yearly. Nowadays, replacement of the ACL with autologous tendons (tendon of the semitendinosus and/or gracilis muscle = “Hamstrings” or Patella tendon) is a method of first choice. Due to different problems following explantation of the above mentioned tendons; e.g. femoropatellar pain syndrome, weakening of the bending strength of the knee, or because of the re-rupture of autologous ACL-transplants, there is a search for alternatives in the ACL-surgery. Tissue engineering offers a perspective in response to this problem. Hereby, biological or artificially synthesized frame tissue is grown together with cells under defined conditions to initiate differentiation of the cells into particular target tissue. In this work, the biomechanical characteristics of the three biocompatible polymers Polyglycol acid (PGA), Polylactic acid (PLLA) and polyvinylidene fluoride (PVDF) were examined and compared with the biomechanical characteristics of the ACL of Merino-sheep. All materials mentioned are already used in the medicine. In collaboration with the Institute of textile technology (ITA) of the Technical University of Aachen-Germany (RWTH Aachen), the polymers were knitted to form a porous fabric which was later on filled with a consolidated type I collagen gel. The aim of this work was to develop a hybrid construct, which merges the biological characteristics of collagen (cell growth possible) with the biomechanical characteristics of synthetic polymers and becomes a suitable material for ACL replacement. The biomechanical characteristics of the hybrids (ultimate tensile strength, distension, stretching, tension and rigidity) were examined by uni-axial traction tests. Ultimate tensile strength and rigidity of the sheep ACL were significantly higher (p<0.0001) than the values of all three hybrids. Among the polymers, PVDF showed the best biomechanical stability, followed by PGA and PLLA. The elasticity and distension of the knitted polymer fabrics were significantly higher than the values of the anterior cruciate ligament of the Merino-sheep. The ACL of the sheep showed a maximum stretch of 32.71 ± 12.19 %, while PGA, PVDF and PLLA hybrid constructs showed 73.27 ± 10.40%, 139.76 ± 23.09% und 141.65 ± 10.04 respectively. The results of biomechanical investigation with an experimental setup, which has been validated in literature, permit the conclusion that none of the examined materials exhibits the required biomechanical characteristics, making it suitable for replacement of the ACL in human beings.Aachen : Publikationsserver der RWTH Aachen University III, 68 S. : Ill., graph. Darst. (2009). = Aachen, Techn. Hochsch., Diss., 2009info:eu-repo/semantics/doctoralThesisinfo:eu-repo/semantics/publishedVersionPublikationsserver der RWTH Aachen University2009info:eu-repo/semantics/openAccessDEhttps://publications.rwth-aachen.de/record/51136https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113451%22StudentsStudent Financial Aid ProvidersTeachersResearchersinfo:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-28205