Question
| A. |
Trapezium |
| B. |
Trapezoid |
| C. |
Lunate |
| D. |
Capitate |
|
Correct Answer » C Explanation |
 |
The lunate is centrally placed in the proximal row of carpal bones and plays a key role in wrist stability. It is the second most commonly injured carpal bone, most often involved in dislocations rather than fractures.
Lunate dislocation usually occurs due to high-energy trauma such as a fall on an outstretched hand or road traffic accidents. It may compress the median nerve and cause acute carpal tunnel syndrome. On lateral wrist X-ray, lunate dislocation produces the classic “spilled teacup sign.”
Explanation of Other Options
A. Trapezium
Trapezium fractures are uncommon and usually occur due to direct trauma to the base of the thumb. It is not the second most commonly injured carpal bone.
B. Trapezoid
Trapezoid fractures are very rare because it is strongly supported by surrounding ligaments. It is one of the least commonly injured carpal bones.
D. Capitate
Capitate is the largest carpal bone. Its fractures are uncommon and usually associated with severe trauma. It is not the second most commonly injured carpal bone.
