Avascular necrosis is not uncommon. select the type of fracture or dislocation with which it is most likely to be associated (SELECT 1 INJURY)
**Core Concept**
Avascular necrosis refers to the death of bone tissue due to a lack of blood supply. This condition can occur following a traumatic injury, particularly those that disrupt the blood vessels supplying the bone. The femoral head is a common site for avascular necrosis due to its delicate blood supply.
**Why the Correct Answer is Right**
The type of fracture or dislocation most likely to be associated with avascular necrosis is a hip dislocation. When the hip joint is dislocated, the blood vessels that supply the femoral head can be damaged, leading to a disruption in blood flow and subsequent avascular necrosis. This is particularly true for posterior dislocations, which can cause the femoral head to be compressed against the posterior wall of the acetabulum, damaging the blood vessels.
**Why Each Wrong Option is Incorrect**
* **Option A:** Femoral neck fractures can also lead to avascular necrosis, but they are not as likely to cause it as hip dislocations.
* **Option B:** Shoulder dislocations are less likely to cause avascular necrosis in the humeral head compared to hip dislocations.
* **Option C:** Knee dislocations can cause avascular necrosis in the femoral condyles, but the likelihood is lower compared to hip dislocations.
**Clinical Pearl / High-Yield Fact**
Hip dislocations, particularly posterior dislocations, are a significant risk factor for avascular necrosis of the femoral head. It is essential to promptly and accurately diagnose hip dislocations to prevent or mitigate this complication.
**Correct Answer:** C.