BACKGROUND:
The aim of this paper was to review the outcomes of treatment of dislocated but reducible (Ortolani-positive) hips.

METHODS:
A comparative retrospective review was conducted of all patients aged younger than 6 months who presented for treatment of developmental dysplasia of the hip for two 10-year periods. The inclusion criteria consisted of a clinical evaluation documenting Ortolani-positive examination, no previous treatment, and an initial treatment with Pavlik harness only. Patients with insufficient follow-up, neuromuscular disease, provocative dislocatable hips, or dislocated but not reducible hips were excluded. In group 1 (1984-1994), treatment involved initiation of Pavlik harness and parental education at the time of initial diagnosis. Group 2 (1997-2007) was treated the same as group 1 with the addition of serial orthopaedic office-based ultrasound examinations and use of a hip abduction orthosis in hips remaining unstable after 3 weeks in the Pavlik harness. Records were assessed for successful achievement and maintenance of hip reduction, need for and type of further treatment, and development of avascular necrosis.

RESULTS:
In group 1, the mean time of follow-up was 28 months. Forty-four (85%) of 52 hips were treated successfully. Eight patients required further operative treatment. In group 2, the mean follow-up to the final evaluation was 34 months. Forty-one (93%) of 44 hips were treated successfully. Three hips required further treatment. There were no documented cases of avascular necrosis in patients treated for orthoses only in either group.

CONCLUSIONS:
In 1994, we presented a series of 52 Ortolani-positive hips (group 1) with a success rate of reduction of 85%. Now, our protocol for treating Ortolani-positive hips has evolved to include serial orthopaedic office-based ultrasound in all patients and use of a hip abduction orthosis in hips remaining unstable after 3 weeks in a Pavlik harness. Three previous studies at major centers reported successful reduction in only 63% to 71%. In group 2, our current success rate of 93% exceeds that previously reported by us and is significantly greater than these 3 previous studies (all P < 0.006). Furthermore, our current treatment module has decreased our rate of open reduction from 10% in group 1 to 5% in group 2. LEVEL OF RELEVANCE: Therapeutic study, level 3.