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Updated: Jun 14, 2025

Treatment of Ligament Constructs with Exercise-conditioned Serum: A Translational Tissue Engineering Model
Published on: June 11, 2017
What Do We Know About Ligaments?
Joe Iwanaga1,2,3,4,5,6, Keishiro Kikuchi6,7, Mi-Sun Hur8
1Department of Neurosurgery, Clinical Neuroscience Research Center, Tulane University School of Medicine, New Orleans, Louisiana, USA.
Abstract:
Ligaments have been extensively studied in anatomy and are traditionally defined as structures that connect bones and contribute to joint stability. However, a universally accepted definition of "ligament" remains elusive. Many structures classified as ligaments do not connect bones, such as the ligamentum arteriosum, raising questions about the criteria used for their designation. Moreover, distinguishing ligaments from tendons presents a significant challenge because of their shared histological characteristics and the lack of a clear, standardized definition of "ligament". Historically, ligaments have been named primarily on the basis of their gross anatomical appearance rather than well-defined structural or functional criteria. Ambiguities in nomenclature such as the interchangeable use of "patellar ligament" and "patellar tendon" further complicate classification. Additionally, dissection bias can lead to the artificial identification of ligaments because traditional dissection techniques can isolate tissue layers in a manner that creates the illusion of distinct ligament structures. Given these limitations, gross anatomical dissection alone is insufficient to confirm the presence of a ligament, necessitating histological validation based on a fundamental definition. Establishing a precise classification system that differentiates traditional bone-to-bone ligaments from other connective structures is imperative. Close collaboration between anatomists and surgeons is essential for refining anatomical definitions because inaccurate classifications can have direct implications for clinical practice, particularly in ligament reconstruction. A research-driven, standardized definition of ligaments can enhance anatomical education and improve surgical precision.
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