In forceful inversion of foot, fracture of the tuberosity of 5th metatarsal is due to pull exeed by which tendon?
## **Core Concept**
The question tests knowledge of foot anatomy and the mechanism of injury for a specific type of fracture. The 5th metatarsal bone is a common site for fractures, particularly the tuberosity, which is subjected to avulsion fractures due to the pull of a specific tendon.
## **Why the Correct Answer is Right**
The correct answer, **peroneus brevis tendon**, is right because the tuberosity of the 5th metatarsal serves as the insertion point for the peroneus brevis tendon. During forceful inversion of the foot, the peroneus brevis tendon exerts a pulling force on the tuberosity, which can lead to an avulsion fracture. This type of fracture is known as a Jones fracture.
## **Why Each Wrong Option is Incorrect**
- **Option A:** The **tibialis anterior tendon** primarily inserts on the medial and inferior surfaces of the medial cuneiform and the base of the 1st metatarsal bone. It is not associated with the 5th metatarsal tuberosity.
- **Option B:** The **peroneus longus tendon** passes under the foot and inserts on the base of the 1st metatarsal and medial cuneiform. It does not attach to the 5th metatarsal.
- **Option D:** The **tibialis posterior tendon** inserts on the tuberosity of the navicular bone and sends slips to the cuneiforms, cuboid, and the bases of the 2nd to 4th metatarsals, not the 5th metatarsal.
## **Clinical Pearl / High-Yield Fact**
A classic clinical correlation to remember is that a Jones fracture, which is a fracture of the tuberosity of the 5th metatarsal, is often caused by a sudden contraction of the **peroneus brevis** muscle during forceful inversion of the foot. This type of fracture can be challenging to heal due to poor blood supply to the area.
## **Correct Answer:** B. peroneus brevis tendon