Hip Dislocations and Reduction Techniques

Hip Dislocations

*Dislocations and fracture-dislocations are true orthopedic emergencies

History:

ABC’s: This injury is a red flag for multisystem injury

Mechanism

Significant force

High speed MVC (often sans seat belt)
- Flexed knee hits dashboard
Falls
Pedestrian struck
Anterior dislocations (10-15%) forceful extension, abduction, and external rotation
Central dislocations (2-4%) femoral head forced into shattered acetabulum

Physical Exam

Posterior dislocation
- Hip flexed, adducted, and internally rotated
- Knee of the affected extremity rests on the opposite thigh
- Extremity shortened
- Greater trochanter and buttock may be unusually prominent.
Anterior dislocation
- Hip in abduction, slight flexion, and external rotation
- Leg may appear lengthened

Diagnosis:

Plain Xrays

Treatment

Relationship between time of hip dislocation and AVN

<6 hrs 4.8%

>12 hrs 58.8%

*Conscious sedation generally required for reduction

Allis technique for reduction of posterior hip dislocation:

The patient is placed in the supine position, and the pelvis is stabilized by an assistant.
With the knee flexed, the operator applies steady traction in line with the deformity.
The hip is slowly brought to 90 degrees of flexion while steady upward traction and gentle rotation are applied.
The assistant pushes the greater trochanter forward toward the acetabulum.
Once reduction has been achieved, the hip is brought to the extended position while traction is maintained.

Stimson’s technique for reduction of posterior hip dislocation:

The patient is placed in a prone position, with the leg hanging over the edge of the bed. The hip and knee are flexed at 90 degrees.
An assistant stabilizes the pelvis.
The operator applies steady downward traction in line with the femur.
The femoral head is gently rotated, and the assistant pushes the greater trochanter anteriorly toward the acetabulum.
Once reduction has been achieved, the hip is brought to the extended position while traction is maintained.

Captain Morgan technique

Dislocation of Hip Prosthetics

230,000 undergo elective primary THA each year
Post-op dislocation 0.5-3% of primary THA
5-27% of revised THA dislocate
Posterior dislocation 75-90%
Often can be with low force (ie getting out of chair, rolling over in bed, bending over)
Same reduction technique but need ortho as will often need OR/ revision
Time not as critical for AVN, however still can damage sciatic nerve

References

Rosen’s Emergency Medicine Chapter 56, p.672-697 e2
DeLee & Drez’s Orthopaedic Sports Medicine.
Hendey. Avila Captain Morgan Technique for reduction of Dislocated Hip. Annals of Emergency Medicine Vol 58.no6 Dec 2011.