The extensor hood is another name for which structure?

The extensor hood is another name for which structure?

• A. Dorsal interosseous membrane
• B. Flexor tendon sheath
• C. Extensor expansion ligament
• D. Ulnar collateral ligament

Answer: (C)

The extensor hood is the dorsal digital expansion, the extensor expansion ligament that forms the expanded extensor mechanism over the fingers. It develops from the extensor digitorum tendon as it splits into a central slip and two lateral bands, which then blend with the lumbricals and interossei to create a hood that attaches to the phalanges. This thickened tissue is what coordinates extension of the finger joints with intrinsic muscle action, and that’s why the extensor hood is another name for the extensor expansion (dorsal digital expansion). Other structures listed are different: the dorsal interosseous membrane lies between metacarpals on the dorsum, the flexor tendon sheath surrounds the flexor tendons, and the ulnar collateral ligament supports the thumb joint.

The extensor hood is the dorsal digital expansion, the extensor expansion ligament that forms the expanded extensor mechanism over the fingers. It develops from the extensor digitorum tendon as it splits into a central slip and two lateral bands, which then blend with the lumbricals and interossei to create a hood that attaches to the phalanges. This thickened tissue is what coordinates extension of the finger joints with intrinsic muscle action, and that’s why the extensor hood is another name for the extensor expansion (dorsal digital expansion). Other structures listed are different: the dorsal interosseous membrane lies between metacarpals on the dorsum, the flexor tendon sheath surrounds the flexor tendons, and the ulnar collateral ligament supports the thumb joint.