The plantar cuboid-navicular ligament connects the plantar surface of the navicular to the plantar surface of the cuboid, stabilising the transverse tarsal (Chopart) joint from the plantar aspect. It works alongside the plantar calcaneonavicular (spring) ligament and the short plantar ligament to maintain the plantar midfoot arch integrity.
Stabilises the transverse tarsal joint from below, prevents excessive dorsiflexion of the navicular-cuboid complex, and contributes to the medial and lateral longitudinal arch support.
The plantar cuboid-navicular ligament is stressed in midfoot arthritis and in Chopart joint injuries that involve the complete ligamentous complex. In total arch collapse from posterior tibial tendon dysfunction, the plantar ligaments including this structure become attenuated. Lisfranc and Chopart combined injuries may involve this ligament, requiring recognition for complete midfoot reconstruction. The ligament is not a common isolated injury but contributes to midfoot instability patterns.
Progressive attenuation of the plantar midfoot ligaments including the cuboid-navicular and spring ligaments accompanies stage II and III posterior tibial tendon dysfunction, allowing progressive midfoot abduction and hindfoot valgus deformity managed by medial column stabilising procedures and calcaneal osteotomy.