The early detection and management of unstable concentric closed reduction of DDH with percutaneous K-wire fixation in infants 6 to 12 months of age.

BACKGROUND: In some infants with developmental dysplasia of the hip, concentric closed reduction, although initially achievable, cannot be maintained even by casting because of a deficient posterior acetabular wall. Usually, these hips will redislocate in the cast and a rereduction will be necessary, often requiring an open reduction subsequently.
METHODS: A 3-year retrospective review of 88 infants, (M/F; 14/74) 6 to 12 months of age with 124 dislocated hips, was conducted to assess the efficacy of percutaneous Kirschner wire fixation in achieving permanent hip stability. A "hip-at-risk" instability test was developed to detect potentially unstable hips at the time of closed reduction that might redislocate in the hip spica cast, and these hips were stabilized with a percutaneous K-wire through the greater trochanter into the pelvic bone.
RESULTS: The hip instability test was positive in 27 hips and negative in 97. Percutaneous K-wire fixation was used to stabilize 21 hips with a positive hip instability test. All 21 unstable hips that were stabilized with the K-wire technique maintained their concentric reduction and went on to stable development. No K-wire breakage was encountered and only 1 superficial pin tract infection occurred.
CONCLUSIONS: K-wire stabilization of unstable closed reductions is a safe, reliable technique for maintaining concentric hip reduction in infants 6 to 12 months of age with developmental dislocation of the hips. LEVEL OF EVIDENCE: Level II retrospective study.