Hip dislocation

Question 1

Why emergency?

Answer 1

Disrupt supply to femoral head: Avascular necrosis

1. ascending cervical branch (medial circumflex)
2. artery of ligamentum teres (patent only up to 7 years old)
3. superior gluteal artery
4. sciatic nerve

Question 2

Anatomy

Answer 2

Ligament
Pubofumeral
Tibio
Ischio

Muscle
Nerve

Question 3

Mechanism of injury

Answer 3

1. Dashboard injury: Posterior dislocation
   - hit knee, displace backwards
2. Terkangkang: Anterior dislocation

Question 4

CF

Answer 4

Internally rotates
flexion
adducted

Question 5

X-Ray

Answer 5

Cannot see lesser trochanter (internally rotated)

Question 6

Reduction

Answer 6

1. Bigelow’s method
2. Alice’s method
3. Stimson’s method

Question 7

Telescoping test +ve

Answer 7

1. Acetabular fracture (posterior wall)

2. Soft tissue interposition, or incarcerated fragment (ligament, labrum)

Question 8

Complication

Answer 8

Early

• sciatic nerve injury
• associated fracture

Late

• avascular necrosis (increases with time)
• osteochondritis dissecans
• osteoarthritis