Hindfoot joint pressure in supination sprains

Area of Science:

• Biomechanics
• Orthopedic Surgery
• Sports Medicine

Background:

• Hindfoot trauma, such as ankle and subtalar sprains, can lead to osteochondral lesions (OCLs) and chronic pain due to posttraumatic arthritis.
• These injuries often result from stress concentrations in the medial ankle and subtalar joint during supination sprains.

Purpose of the Study:

• To investigate the impact of acute severe and mild hindfoot supination sprains with increasing ligamentous incompetence on intra-articular pressure and center of force (COF) migration.
• To determine the contribution of intra-articular pressure elevation to the development of OCLs in the ankle and subtalar joints.

Main Methods:

• A controlled laboratory study simulating "acute severe" sprains and "mild sprains with increasing ligamentous incompetence" (transections of ATFL, CFL, LTCL) in human lower leg specimens.
• Measuring the migration of the center of force (COF) and tibiotalar/subtalar pressures under static and dynamic axial loads using pressure sensors.

Main Results:

• "Acute severe" sprains significantly increased peak pressure in the ankle and subtalar medial facet, with significant medial and posterior COF migration.
• "Mild sprains with increasing ligamentous incompetence" also showed significant peak pressure increases in the ankle and subtalar medial facet.
• Ligamentous incompetence (ATFL, CFL, LTCL transections) significantly altered ankle COF migration patterns, with posterior shifts observed when the CFL was compromised.

Conclusions:

• Intra-articular pressure elevation during hindfoot supination sprains, whether ligaments are intact or incompetent, contributes to OCLs in the medial talar dome and subtalar joint.
• The findings underscore the substantial role of intra-articular hindfoot pressure changes in the pathogenesis of OCLs, particularly in "acute severe" and "mild" sprain scenarios with ligamentous incompetence.