**Core Concept**
Trochanteric fractures of the femur are a type of hip fracture that occurs in the proximal femur, specifically in the area between the greater and lesser trochanters. These fractures often require surgical intervention to restore hip function and prevent complications such as nonunion or malunion.

**Why the Correct Answer is Right**
The best treatment for trochanteric fractures is usually an intramedullary nail or a sliding hip screw. These surgical techniques allow for stable fixation of the fracture fragments, promoting healing and minimizing the risk of complications. The intramedullary nail is inserted into the femoral canal, while the sliding hip screw is attached to the femur and the acetabulum, providing additional stability to the fracture site.

**Why Each Wrong Option is Incorrect**
**Option A:** Closed reduction and percutaneous pinning is not typically used for trochanteric fractures due to the high risk of nonunion and malunion.
**Option B:** External fixation is not suitable for trochanteric fractures as it does not provide sufficient stability for the fracture site to heal properly.
**Option C:** Arthroplasty is usually reserved for patients with severe osteoporosis or those who are not candidates for surgical fixation.

**Clinical Pearl / High-Yield Fact**
The timing of surgical intervention for trochanteric fractures is critical, as delayed fixation can lead to increased morbidity and mortality. Early surgical treatment within 24-48 hours of injury is recommended to improve outcomes and reduce complications.

**Correct Answer: B. External fixation is not suitable for trochanteric fractures as it does not provide sufficient stability for the fracture site to heal properly.**