Plantar Calcaneonavicular Ligament Facet, Inferior View

Description

Talar head anatomy dominates the frame, with the inferior surface oriented toward the viewer and the neck extending proximally toward the ankle mortise. Along the plantar aspect of the head, the smooth, bean shaped facet for the plantar calcaneonavicular (spring) ligament sits just inferior to the talonavicular articular surface and medial to the more lateral contours that relate to the anterior subtalar region. The margins of this ligamentous facet blend into adjacent nonarticular bone, clarifying where the spring ligament supports the talar head rather than forming a hyaline cartilage joint surface. Orientation is unmistakable. Spring ligament integrity is a key determinant of medial longitudinal arch height because it forms the fibrocartilaginous sling beneath the talar head and cooperates with the tibialis posterior tendon and deltoid ligament complex to resist plantar and medial displacement of the talus. That makes this inferior perspective useful when teaching adult acquired flatfoot deformity (progressive collapsing foot deformity), where attenuation or rupture of the plantar calcaneonavicular ligament contributes to talar head uncovering at the talonavicular joint and plantar sag. The isolated focus on the talar head’s plantar facet also supports operative planning discussions for talonavicular arthrodesis, spring ligament reconstruction, or medializing calcaneal osteotomy by grounding the conversation in an exact bony contact area rather than a generic “arch support” concept. Use this illustration in gross anatomy and orthopaedic foot and ankle modules to reinforce ligament attachment topography, and in radiology or surgical texts when correlating CT or MRI findings of spring ligament injury with talar head position at the talonavicular joint. It also suits patient education graphics for pes planovalgus when you need a precise, single-structure reference for where the spring ligament meets the talus. Anatomical accuracy verified by SciePro's Medical Advisory Board.