DDFT and navicular apparatus participate in the stay mechanism by providing distal limb support. Which statement is true?

• A. They distribute load by compressing the coffin joint.
• B. They provide distal limb support by applying tension across the coffin joint and helping to distribute load through the navicular complex.
• C. They do not contribute to load distribution.
• D. They are not involved in stay mechanism.

Answer: (B)

In the stay mechanism, the distal limb is held up by passive structures that work under tension rather than by muscular force alone. The deep digital flexor tendon is pulled taut as the limb bears weight, and the navicular apparatus acts like a pulley that redirects this tensile force across the coffin joint. This tension helps distribute the load through the navicular complex, spreading forces across the distal structures and stabilizing the pastern and coffin joints with minimal muscular effort.

So the correct statement fits because it describes load-bearing achieved by applying tension across the coffin joint and distributing load through the navicular complex. The other ideas imply compression, no contribution, or lack of involvement, which doesn’t match how the stay mechanism actually functions.