The Hip: Preservation, Replacement and Revision

Impediments to Reduction in DDH



- See:
      - Pathogenesis of DDH
      - Table I

- Discussion:
    - soft-tissue impediments to adequate reduction include:
         - constriction of the joint capsule of hip: most important type of obstruction in older children;
         - contraction of the psoas tendon over acetabular inlet;
         - hypertrophy of the transverse acetabular ligament;
         - pulvinar, or the ligamentum teres;
              - as children reach walking age, hypertrophy of the ligament may preclude hip reduction unless ligament is excised;
         - inverted neolimbus:
              - rare type of obstruction in DDH;
              - formed when dislocated femoral head is above or behind labrum;
              - lip of hypertrophied fibrocartilage may be infolded or everted;
              - may be adherent to hip capsule or supra-acetabular iliac wall;

- Infants Younger than 2 months;
    - when soft-tissue impediments prevent congruent reduction, positioning of hip in safe position (using Pavlik harness) may allow femoral head to overcome soft tissue impediments & become adequately reduced;
           - do not continue w/ this form of treatment for more than 4 weeks, since process of acetabular dysplasia and soft tissue adaptive changes will continue as long as hip remains dislocated;

- Infants Older than 2 months;
    - in children who are older than two months, spica cast may allow femoral head to overcome soft tissue impediments & become adequately reduced;
           - do not continue w/ this form of treatment for more than 4 weeks, since process of acetabular dysplasia and soft tissue adaptive changes will continue as long as hip remains dislocated



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, August 9, 2012 1:16 pm