Crosses the navicular bone and attaches to the underside of the coffin bone and has a check ligament?

Crosses the navicular bone and attaches to the underside of the coffin bone and has a check ligament?

• A. deep digital flexor tendon
• B. superficial flexor tendon
• C. common digital extensor tendon
• D. suspensory ligament

Answer: (A)

The deep digital flexor tendon is the structure that crosses the navicular bone and attaches to the underside of the coffin bone, and it has a check ligament. As the limb flexes, the deep digital flexor tendon pulls on the distal phalanx (coffin bone) to raise the sole and flex the joint. The navicular bone sits between the tendon and the coffin bone, with a specialized tendon passage and often a navicular bursa to reduce friction. The associated check ligament helps anchor the tendon proximally, limiting its excursion and preventing excessive bowstringing, which keeps the tendon aligned with the coffin joint and maintains efficient transmission of muscular force. The other structures do not cross the navicular bone in this way or attach to the underside of the coffin bone with a check ligament, which is why they don’t fit this description.

The deep digital flexor tendon is the structure that crosses the navicular bone and attaches to the underside of the coffin bone, and it has a check ligament. As the limb flexes, the deep digital flexor tendon pulls on the distal phalanx (coffin bone) to raise the sole and flex the joint. The navicular bone sits between the tendon and the coffin bone, with a specialized tendon passage and often a navicular bursa to reduce friction. The associated check ligament helps anchor the tendon proximally, limiting its excursion and preventing excessive bowstringing, which keeps the tendon aligned with the coffin joint and maintains efficient transmission of muscular force. The other structures do not cross the navicular bone in this way or attach to the underside of the coffin bone with a check ligament, which is why they don’t fit this description.