Is There a Benefit to Weaning Pavlik Harness Treatment in Infantile DDH?

BACKGROUND: Following successful treatment of developmental hip dysplasia with a Pavlik harness, controversy exists over the benefit of continued harness use for an additional "weaning" period beyond ultrasonographic normalization versus simply terminating treatment. Although practitioners are often dogmatic in their beliefs, there is little literature to support the superiority of 1 protocol over the other. The purpose of this study was to compare the radiographic outcomes of 2 cohorts of infants with developmental hip dysplasia treated with Pavlik harness, 1 with a weaning protocol and 1 without. METHODS: This was a comparative review of patients with dislocated/reducible hips and stable dysplasia from 2 centers. All patients had pretreatment ultrasounds, and all started harness treatment before 3 months of age. On the basis of power analysis, a sufficient cohort of hips were matched based on clinical examination, age at initiation, initial α angle, and initial percent femoral head coverage. Patients from institution W (weaned) were weaned following ultrasonographic normalization, whereas those from institution NW (not weaned) immediately ceased treatment. The primary outcome was the acetabular index at 1 year of age. RESULTS: In total, 16 dislocated/reducible and 16 stable dysplastic hips were matched at each center (64 total hips in 53 patients). Initial α angle and initial femoral head coverage were not different between cohorts for either stable dysplasia (P=0.59, 0.81) or dislocated/reducible hips (P=0.67, 0.70), respectively. As expected, weaned hips were treated for significantly longer in both the stable dysplasia (1540.4 vs. 1066.3 h, P<0.01), and dislocated/reducible cohorts (1596.6 vs. 1362.5 h, P=0.01). Despite this, we found no significant difference in the acetabular index at 1 year in either cohort (22.8 vs. 23.1 degrees, P=0.84 for stable dysplasia; 23.9 vs. 24.8 degrees, P=0.32 for Ortolani positive). CONCLUSIONS: Despite greater total harness time, infants treated with additional Pavlik weaning did not demonstrate significantly different radiographic results at 1 year of age compared with those who were not weaned. However, differences in follow-up protocols between centers support the need for a more rigorous randomized controlled trial. LEVEL OF EVIDENCE: Level III.