Least mobile metatarsal of foot
**Core Concept**
The foot's metatarsals have varying degrees of mobility, which affects their susceptibility to injuries and conditions. The metatarsals' mobility is influenced by their articulations with adjacent bones and the surrounding soft tissues. In the foot, the metatarsals can be classified based on their mobility, with the first metatarsal being relatively fixed and the others being more mobile.
**Why the Correct Answer is Right**
The first metatarsal bone is the least mobile due to its strong connection to the medial cuneiform bone and the first metatarsophalangeal joint. This connection limits its ability to move compared to the other metatarsals. The first metatarsal's mobility is also restricted by the presence of the medial and intermediate plantar ligaments, which provide additional stability to the foot.
**Why Each Wrong Option is Incorrect**
* **Option A:** The second metatarsal is relatively mobile, but not the least mobile.
* **Option B:** The third metatarsal is mobile, but its mobility is not as limited as the first metatarsal.
* **Option D:** The fifth metatarsal has a unique attachment to the cuboid bone and the peroneus longus tendon, which increases its mobility.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the first metatarsal's limited mobility makes it more susceptible to stress fractures, particularly in runners and athletes who participate in high-impact activities.
**Correct Answer:** C.