Question

Consider the following statements regarding hip dislocation: 1. Hip dislocation occurs in high velocity injuries. 2. Posterior dislocation is common. 3. Prompt reduction is required. 4. Avascular necrosis is infrequent. Which of these statements are correct?

• A. 1 and 4
• B. 2 and 3
• C. 1, 2 and 3
• D. 1, 3 and 4

Hint:

One of the four statements contradicts why this injury is treated as an emergency - find it.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
This question is checking which statements about traumatic hip dislocation are true, covering how it happens, which direction is most common, and how urgently it must be treated.

Step 2: Key Concept or Approach:
The hip joint is deep and inherently stable, so dislocating it takes a large amount of force, and the blood supply to the femoral head (mainly through the retinacular vessels around the neck) is easily torn or kinked when the joint is dislocated, which is why timing of reduction matters so much.

Step 3: Working Through the Options:
Statement 1 is true - hip dislocation needs high-velocity trauma, classically a dashboard injury in a road traffic accident, because the joint is normally very stable. Statement 2 is true - posterior dislocation, where the femoral head is driven backward out of the acetabulum, accounts for the large majority of traumatic hip dislocations. Statement 3 is true - reduction is an orthopaedic emergency, since the longer the femoral head stays dislocated, the more the blood supply through the retinacular vessels is compromised. Statement 4 is false - avascular necrosis of the femoral head is a well recognised and relatively frequent complication of hip dislocation, not an infrequent one, which is exactly why prompt reduction (statement 3) is stressed.

Step 4: Conclusion:
Statements 1, 2 and 3 are correct.