Palmar nerve block would desensitize which structure innervated by the palmar nerves?

Palmar nerve block would desensitize which structure innervated by the palmar nerves?

• A. Navicular bone
• B. Lateral digital cushion
• C. Carpal bones
• D. Carpus joints

Answer: (A)

Palmar nerves carry sensory signals from the palmar aspect of the distal limb, including the coffin region. The navicular bone (coffin bone) is a structure that is innervated by these palmar digital nerves, so a palmar nerve block stops pain signals from that bone. This is why desensitizing the navicular bone is a classic outcome of a palmar nerve block and is often used to localize navicular disease or coffin-area pain. The other structures listed are not the primary targets for this block in the same way. The carpal bones and carpus joints are proximal and receive innervation from multiple sources, not solely the palmar nerves at the distal limb. The lateral digital cushion is also related to the palmar digital nerves, but the navicular bone is the hallmark structure classically desensitized by a palmar nerve block in this context.

Palmar nerves carry sensory signals from the palmar aspect of the distal limb, including the coffin region. The navicular bone (coffin bone) is a structure that is innervated by these palmar digital nerves, so a palmar nerve block stops pain signals from that bone. This is why desensitizing the navicular bone is a classic outcome of a palmar nerve block and is often used to localize navicular disease or coffin-area pain.

The other structures listed are not the primary targets for this block in the same way. The carpal bones and carpus joints are proximal and receive innervation from multiple sources, not solely the palmar nerves at the distal limb. The lateral digital cushion is also related to the palmar digital nerves, but the navicular bone is the hallmark structure classically desensitized by a palmar nerve block in this context.