Hip dislocations

Epidemiology:

-        rare, but high incidence of associated injuries

-        mechanism is usually young patients with high energy trauma

Simple vs. Complex:

o   simple

• pure dislocation without associated fracture

o   complex

• dislocation associated with fracture of acetabulum or proximal femur

-Anatomic classification:

o   posterior dislocation (90%):

• occur with axial load on femur, typically with hip flexed and adducted
• axial load through flexed knee (dashboard injury)
• hip and leg in slight flexion, adduction, and internal rotation
• examine knee for associated injury or instability

o   anterior dislocation:

• associated with femoral head impaction or chondral injury
• occurs with the hip in abduction and external rotation
• hip and leg in flexion, abduction, and external rotation

Imaging:

X-rays:

-        Can typically see posterior dislocation on AP pelvis

o   femoral head smaller than contralateral side

o   Shenton's line broken

o   Look at the femoral neck to rule out fracture prior to attempting closed reduction

o   AP pelvis after reduction to evaluate associated acetabular fractures

CT:

-        post reduction CT must be performed for all traumatic hip dislocations to look for:

o   femoral head fractures

o   loose bodies

o   acetabular fractures

Management:

1. Nonoperative
2. emergent closed reduction within 6 hours!
3.      indications:
4. acute anterior and posterior dislocations
5.      contraindications
6. ipsilateral displaced or non-displaced femoral neck fracture
7. Allis maneuver:

-        patient is placed in the supine position

-        knee is flexed to relax the hamstring

-        assistant stabilizes the pelvis

-        longitudinal traction is applied in line w/ axis of femur, and the hip is slightly flexed

-        gently adduct& internal rotates the femur to get reduction

https://www.youtube.com/watch?v=2dT1r_U7LQ8

2. Captain Morgan technique:

-        Position the patient: 90 degrees of hip and knee flexion

-        Step one foot up nto the gurney Captain-Morgan style (flamboyant cape optional).

-        Position your knee behind the patient’s knee.

-        Ideally your foot should be resting on a hard surface like a backboard to allow your foot to push off of it.

-        Place one hand (A) under the patient’s knee and the other (B) over the patient’s ankle.

-        Use Hand A to lift up on the patient’s femur.

-        Plantar-flex your ankle so that your propped knee can lift up on the patient’s femur

-        Very gently use Hand B to leverage-down on against the patient’s tibia/fibula.

https://www.youtube.com/watch?v=Uhkc7I4G7ng

2. Operative
   1. open reduction and/or removal of incarcerated fragments
   2.      irreducible dislocation
   3.      radiographic evidence of incarcerated fragment
   4.  delayed presentation 

1. ORIF
2. associated fractures of:
   1. acetabulum
   2. femoral head
   3. femoral neck

Sources: Ortho Bullets, ALiEM, Wheeless’ Textbook of Orthopaedics