Pediatric Hip Dislocation & Reduction
Resident Clinical Pearl (RCP) – November 2022
Dr. Nick Byers , R2 iFMEM, Dalhousie University, Saint John, New Brunswick
Reviewed/Edited by Dr. Brian Ramrattan
Case:
A 10 year old presents to the local emergency department after playing with their sibling. The child was “tackled” from behind. A history and physical exam inform you that the child has been healthy until now with a completely uneventful childhood. They are normal, healthy body habitus and laying on their right side, a pillow between their flexed left knee & hip, and straight right leg. This is the only position of comfort for the child. Neurovascular exam is normal and the child refuses to let you move the leg at all. Foot and ankle move normally. Xrays were obtained promptly. A dislocated hip was readily identified (note the arrow sign below).
Greater than 85% of traumatic pediatric hip dislocations are posterior. Male children are at a greater risk by a 4:1 ratio, and in younger patients, they often occur with minimal force, whereas older children tend to require much greater forces due to the strength of structures surrounding the joint. Fractures can be an associated injury, though it was not in this case. A general triad to consider when evaluating for posterior dislocation is an adducted, shortened, and internally rotated leg as seen below:
Treatment:
A simple dislocation should be treated with closed reduction under sedation, ideally within six hours of injury to reduce the risk of osteonecrosis of the femoral head.
Reduction techniques:
There are many reduction techniques discussed in the literature. Most involve in-line traction of the femur with abduction and external rotation as the leg lengthens, with counter-traction (or downward pressure) placed on the pelvis. This allows for the femoral head to enter the acetabulum gently.
A quick review of technique with attending staff present on shift included the following three options:
- The Allis maneuver (https://www.youtube.com/watch?v=zmk3vafjAd4): The physician stands on the stretcher with arms hooked under the flexed knee & hip (both at 90o) on the injured side and an assistant provides downward pressure on the pelvis. Hip extension and external rotation can be applied as the hip reduces.
2. The Captain Morgan technique (https://www.youtube.com/watch?v=lQMWaFX-MeQ&t=6s): The physician flexes the injured hip and knee to 90o and places their foot on the stretcher at the injured hip of the patient, their knee under the patients. They then grasp the patient’s leg with one hand under the popliteal fossa and one at the ankle. With counter-traction/downward pressure on the pelvis by an assistant, the physician plantar-flexes their foot to put traction on the patient’s femur. External rotation and abduction can be applied with the lower leg as the hip is reduced.
3. The cannon technique: The stretcher is raised and the patient’s knee and hip are flexed to 90o with the popliteal fossa sitting directly over the physician’s shoulder, hands on the patient’s ankle (while facing the patients feet). An assistant stabilizes and provides downward pressure on the pelvis. The physician slowly stands up straight providing in-line traction on the femur until the hip is reduced.
Case Conclusion:
Once x-rays confirmed a posterior hip dislocation, closed reduction under sedation in the emergency department was performed by a resident and staff physician using the cannon technique. Post-reduction films and repeat neurovascular exams were normal and follow-up with orthopedics was in place before discharge home.
Post reduction film:
References:
https://www.merckmanuals.com/professional/injuries-poisoning/dislocations/hip-dislocations
https://www.emnote.org/emnotes/captain-morgan-hip-reduction-technique
CASTED course manual, Arun Sayal
Traumatic hip dislocation during childhood. A case report and review of the literature. American Journal of Orthopedics (Belle Mead, N.J.), 01 Sep 1996, 25(9):645-649
https://usmlepathslides.tumblr.com/post/64398003332/posterior-hip-dislocation-posterior-hip
https://posna.org/Physician-Education/Study-Guide/Hip-Dislocations-Traumatic
https://www.ochsnerjournal.org/content/18/3/242/tab-figures-data
https://coreem.net/core/hip-dislocation/
https://westjem.com/case-report/emergency-physician-reduction-of-pediatric-hip-dislocation.html