Advanced bioreactor for ligament tissue engineering

Advanced bioreactors are essential for meeting the complex requirements of in vitro ligament tissue engineering. A novel bioreactor system for the functional tissue engineering of ligaments, combined with culture medium perfusion over long periods of time and capability to apply cyclic mechanical loadings to three-dimensional scaffolds independently housed in six chambers, was developed. Well-controlled mechanical stimulations (resolution of <;;0.01mm for translational and <;;0.1° for rotational stress) could be applied to the growing tissue, especially to tissue engineered anterior cruciate ligament (ACL). The novel bioreactor could apply independent tensile/compressive stresses along the same axis and two-way torsions stimulation at the same time. A new type of scaffold relaxation compensation device which could adapt to a range of scaffold length of the changes and be able to realize independently online compensation was designed. The movement control strategies were proposed. This bioreactor is suitable for the tissue engineering of the human knee joint ACLs in both research and clinical applications.