Pavlik harness: Position for Reduction & Safe Zone
- Discussion:
- stable zone:
- ROM in which hip remains reduced w/o subluxation;
- spica cast:
- may be used when reduction has narrow stable zone or when non-compliance w/ harness has been a problem;
- safe zone:
- arc of motion thru which hip remains reduced w/o forced abduction;
- position that does not compromise blood supply to femoral head or create excessive pressure on the epiphysis;
- stable zone should not exceed safe zone;
- if a reduction cannot be maintained in the safe zone (ie, the hip must be placed into severe hyperflexion, internal rotation, or abduction > 70 deg) then operative reduction is indicated;
- remember that a percutaneous adductor tenotomy can be used to increase the safe zone;
- flexion safe zone:
- generally the safe zone is within 100 to 110 deg;
- flexion should be more than 90 but less than 120 deg;
- excessive flexion may result in femoral nerve palsy or fixed posterior dislocation;
- insufficient hip flexion, however, is most common pitfall;
- hips should be flexed 105-120 deg
- x-rays should be taken confirming adequacy of flexion in harness within 2-3 wks of application;
- abduction safe zone:
- safe zone lies between 40 to 60 deg;
- avoid wide abduction which is associated w/ AVN;
- percutaneous release of adductor longus may facilitate reduction when passive abduction is < 70 degrees