Which of the following is not true according to the material?

• A. The palmar ligament holds accessory bones to the hock
• B. The thoracic limb bears more weight
• C. The limb with more check ligaments is the thoracic
• D. The thoracic limb has a reciprocal apparatus

Answer: (D)

In the stay apparatus, the key idea is how joints and tendons coordinate to support weight with minimal muscular effort, especially the presence of a reciprocal mechanism that links joints in the hind limb. The hind limb has a reciprocal apparatus because the peroneus tertius tendon integrates with the superficial digital flexor tendon, tying the stifle and hock so they move together. This means when the animal bears weight, those two joints behave in concert, aiding stability.

The forelimb does not have this reciprocal linkage; its joints are stabilized by other ligaments and tendons that do not couple the analogous joints in the same way. So claiming that the thoracic limb has a reciprocal apparatus is not true.

Other statements describe true aspects of the system: the palmar ligament helps hold accessory bones to the hock, the forelimb bears more weight, and the limb with more check ligaments aligns with how these structures function to limit unwanted motion.