PEDIATRIC TRAUMATIC HIP DISLOCATION

Pediatric traumatic hip dislocation are usually posterior and may occur due to low energy sports injuries in children less than 10 years of age. Hip dislocation are more common than hip fracture in pediatric patients and 80% are traumatic posterior dislocations.

Most of these cases can be diagnosed on AP pelvis films, which show loss of congruence of femoral head with acetabulum. Lateral view is sometimes is used to differentiate between anterior vs. posterior dislocation and to scrutinize femoral neck to rule out fracture prior to attempting closed reduction.

Treatment is urgent closed reduction under general anesthesia or sedation. Open reduction may be required if there is an intraarticular fragment following reduction. Post reduction imagings are necessary to inspect for joint incongruity or nonconcentric reduction.

MRI is a study of choice for any abnormal findings on post-reduction radiographs such as joint widening. In MR study, in inspect for joint incongruity or nonconcentric reduction. Entrapped labrum or capsule is best evaluated via MRI.

CT is second choice behind MRI for post-reduction evaluation, and also radiation exposure should be considered. Osteochondral fragments can be seen in older children and are easily detected by CT.

Delayed in reduction can lead to complications such as osteonecrosis, coxa magna, redislocation or nerve injury.