[The upper ankle joint. Biomechanics and functional anatomy]

Area of Science:

• Biomechanics of the talocrural joint.
• Orthopedic anatomy and ligamentous structures.
• Articular cartilage and joint stability.

Context:

• The talocrural joint exhibits precise rotational motion around an oblique axis.
• Osteocartilaginous contact is the primary source of stability in the loaded ankle.
• Collateral ligaments offer secondary stabilization, stress buffering, and talar centering.

Purpose:

• To elucidate the biomechanical roles of osteocartilaginous structures and ligaments in talocrural joint stability.
• To investigate the functional consequences of ligamentous and cartilaginous lesions.
• To inform clinical therapeutic strategies for ankle injuries.

Summary:

• Dorsoplantar motion occurs around an oblique transverse axis. Ligaments primarily stabilize and center the talus, with specific ligaments dominating under different stress patterns.
• Lesions to singular ligament fascicles or cartilage significantly alter joint motion, indicating high sensitivity to structural integrity.
• Complete reconstruction of damaged structures is clinically indicated due to the ankle's low tolerance for instability and malposition.

Impact:

• Highlights the critical role of intact ligamentous and cartilaginous structures for normal talocrural joint function.
• Emphasizes the prognostic significance of primary cartilage lesions and minor ligamentous damage.
• Suggests limitations in current treatment alternatives due to incomplete understanding of individual biomechanical tolerance.