Abstract
Ligaments and tendons are dense connective tissues that are important in transmitting forces and facilitate joint articulation in the musculoskeletal system. Their injury frequency is high especially for those that are functional important, like the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder. Because the healing responses are different in these ligaments and tendons after injury, the consequences and treatments are tissue- and site-specific. In this review, we will elaborate on the injuries of the knee ligaments as well as using functional tissue engineering (FTE) approaches to improve their healing. Specifically, the ACL of knee has limited capability to heal, and results of non-surgical management of its midsubstance rupture have been poor. Consequently, surgical reconstruction of the ACL is regularly performed to gain knee stability. However, the long-term results are not satisfactory besides the numerous complications accompanied with the surgeries. With the rapid development of FTE, there is a renewed interest in revisiting ACL healing. Approaches such as using growth factors, stem cells and scaffolds have been widely investigated. In this article, the biology of normal and healing ligaments is first reviewed, followed by a discussion on the issues related to the treatment of ACL injuries. Afterwards, current promising FTE methods are presented for the treatment of ligament injuries, including the use of growth factors, gene delivery, and cell therapy with a particular emphasis on the use of ECM bioscaffolds. The challenging areas are listed in the future direction that suggests where collection of energy could be placed in order to restore the injured ligaments and tendons structurally and functionally.
Highlights
Ligaments and tendons are important structures that are designed to transmit forces and facilitate joint articulation in the musculoskeletal system
In the case when the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder are torn, the respective joints can become functionally disabled while the soft tissue in and around the joints including the cartilage, menisci, and others can be predisposed to damage
Previous works had reported the use of hyaluronic acid (HA), basic fibroblast growth factor, collagen-platelet rich plasma (C-PRP) as well as stem cells to heal the central ACL defects[90,91,92,93,94], and all have shown an increased vascularization, increased tissue formation as well as improvements in some of the biomechanical properties
Summary
Ligaments and tendons are important structures that are designed to transmit forces and facilitate joint articulation in the musculoskeletal system. Previous works had reported the use of hyaluronic acid (HA), basic fibroblast growth factor (bFGF), collagen-platelet rich plasma (C-PRP) as well as stem cells to heal the central ACL defects[90,91,92,93,94], and all have shown an increased vascularization, increased tissue formation as well as improvements in some of the biomechanical properties. Different growth factors such as FGF, TGF-β, PDGF, epidermal growth factor (EGF), insulin-like growth factor (IGF), growth and differentiation factor (GDF) and nerve growth factor (NGF) have been shown to improve vascularization and new tissue formation that resulted in improved structural properties of ligamentbone complex[97,98,99,100,101] These growth factors exhibited positive effects on improving ACL healing.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
