Which structure forms the sling apparatus axially?

• A. Proximal cruciate
• B. Interdigital ligament
• C. Distal cruciate
• D. Navicular bone

Answer: (C)

The sling around the distal portion of the limb is formed by the distal sesamoidean ligaments, and the distal cruciate ligaments specifically create the axial sling that holds the navicular area in line with the limb axis. These ligaments cross and wrap around the area of the coffin joint, connecting the navicular bone to the distal phalanx and nearby structures, so they stabilize and support the distal segment as weight is borne. The proximal cruciate ligaments are located more proximally and don’t form this axial sling; the interdigital ligament sits between digits; the navicular bone itself is a bone, not a sling-forming structure.