In posterior dislocation of hip,whole limb is rotated
**Core Concept**
Posterior dislocation of the hip is a serious injury where the femoral head is displaced out of the acetabulum in a posterior direction. This type of dislocation often occurs due to high-energy trauma, such as a motor vehicle accident or a fall from a height. The resulting displacement can cause significant damage to surrounding structures, including nerves and blood vessels.
**Why the Correct Answer is Right**
The characteristic feature of posterior hip dislocation is the external rotation of the entire lower limb. This occurs because the femoral head is displaced posteriorly, which causes the femur to rotate outward. The external rotation is often accompanied by shortening of the affected limb. The mechanism of injury typically involves a combination of abduction and external rotation of the hip, which can lead to the femoral head being displaced out of the acetabulum in a posterior direction.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because internal rotation is typically associated with anterior hip dislocation, not posterior dislocation.
**Option B:** This option is incorrect because flexion of the hip is not a characteristic feature of posterior hip dislocation.
**Option C:** This option is incorrect because adduction of the hip is not typically associated with posterior hip dislocation.
**Clinical Pearl / High-Yield Fact**
It is essential to recognize the characteristic external rotation of the lower limb in posterior hip dislocation, as this can be a crucial clue in the diagnosis of this serious injury. A high index of suspicion should be maintained in patients with a history of high-energy trauma and a characteristic deformity of the lower limb.
**Correct Answer:** D.