A women aged 60 yrs suffers a fall; her lower limb is extended and externally rotated; likely diagnosis is –
**Core Concept**
The patient's presentation of a lower limb extended and externally rotated after a fall is suggestive of a specific type of fracture that involves the hip joint. This clinical presentation is characteristic of a femoral neck fracture, which occurs when the femoral neck, the region between the head and shaft of the femur, is broken.
**Why the Correct Answer is Right**
The mechanism of injury in this patient is likely a fall from a standing height or greater, which can cause a direct blow to the hip, leading to a femoral neck fracture. The external rotation of the lower limb is due to the anatomy of the hip joint and the direction of the force applied during the fall. The femoral head is displaced laterally, resulting in the characteristic outward rotation of the limb. This displacement can lead to a loss of blood supply to the femoral head, which can compromise its viability.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is likely a distractor, as it does not accurately describe the typical presentation of a femoral neck fracture. A hip dislocation would more likely result in a flexed and internally rotated position of the lower limb.
**Option B:** This option may seem plausible, but it is not the correct answer. A subtrochanteric fracture occurs below the femoral neck and is not typically associated with the same degree of external rotation as a femoral neck fracture.
**Option C:** This option is incorrect because a femoral shaft fracture would not typically result in the same degree of external rotation as a femoral neck fracture. The femoral shaft is located below the femoral neck and is not directly involved in the hip joint.
**Clinical Pearl / High-Yield Fact**
In patients with a femoral neck fracture, it is essential to assess for potential complications such as avascular necrosis (AVN) of the femoral head, which can occur due to the disruption of blood supply. This is a critical consideration in the management of these patients, as it can impact their long-term outcomes.
**Correct Answer: D. Femoral neck fracture.**