First tarsometatarsal joint

The first tarsometatarsal joint is the synovial articulation between the base of the first metatarsal and the medial cuneiform.

This joint is part of the Lisfranc joint complex and is characterized by a relatively flat or minimally curved articular surface, with the medial cuneiform typically having a larger articular surface than the first metatarsal base.The joint is stabilized by strong dorsal, plantar, and interosseous ligaments, with the plantar ligaments being particularly robust and contributing to joint stability.

The articular surfaces of the first tarsometatarsal joint are generally tall and narrow, and the opposing surfaces are minimally curved, which allows for limited mobility but provides substantial stability to the medial column of the foot.

During gait, the first metatarsal translates dorsally relative to the medial cuneiform, and the medial cuneiform may show plantar displacement, especially in females, which is associated with increased sagittal mobility and may contribute to hallux valgus pathogenesis.

The joint is frequently involved in Lisfranc injuries, with common patterns including articular surface fractures, joint incongruity, and ligamentous avulsions.