Timing of Repeat Ultrasound Examination in Treatment of Stable Developmental Dysplasia of the Hip

Abstract

Background: Worldwide a wide variation exists in duration of Pavlik harness treatment for infants up to 6 months with stable developmental dysplasia of the hip (DDH). The purpose of this study was to evaluate whether shortening the time to first routine follow-up ultrasound after initiation of Pavlik harness treatment would reduce treatment duration and whether this influenced radiologic outcome at 1 year of age. Furthermore, predictors of higher acetabular index (AI) at 1 year of age were investigated. Methods: A retrospective study was conducted in infants with stable DDH (Graf IIb and IIc) diagnosed and treated between 2015 and 2017. Two groups were identified: first routine follow-up ultrasound at 12 weeks after Pavlik harness initiation (group I) and first routine follow-up ultrasound at 6 weeks after Pavlik harness initiation (group II). In both groups, treatment was continued until repeat ultrasound measurements (every 6 wk) showed a normalized hip. Radiologic outcome at 1 year of age was defined as residual dysplasia measured on an anteroposterior hip radiograph according to the Tönnis table. Results: A total of 222 infants were included. The median time of Pavlik harness treatment was 12 weeks (interquartile range, 11.9 to 12.3) in group I compared with 6.1 weeks (interquartile range, 6.0 to 7.5) in group II ( P <0.001). Residual dysplasia at 1 year of age was detected in 20 infants (16.8%) in group I compared with 11 infants (10.7%) in group II ( P =0.189). The multivariable prediction model showed that positive family history and lower baseline alpha angle correlate with a higher AI at 1 year of age. Conclusions: First routine follow-up ultrasound can be safely brought forward from 12 to 6 weeks after Pavlik harness initiation. Furthermore, infants with a positive family history for DDH and an initial low alpha angle are at higher risk to have a higher AI at 1 year of age. Level of Evidence: Level III—retrospective study.

Principles of Bracing in the Early Management of Developmental Dysplasia of the Hip

“…Hips with stable dysplasia are brought back for US at 6 weeks when most patients come out of harness. This is in agreement with current evidence [61]. Unstable hips are brought back for weekly US and referred to the paediatric orthopaedic clinic if they are not centred by 2 weeks where a decision is made on further management.…”

“…A recent study found introducing US follow-up at 6 weeks significantly reduced the median time in brace from 12 to 6 weeks with no significant increase in dysplastic features at one-year follow-up [61].…”

“…There is limited evidence on the optimal timing or frequency of follow-up and imaging after commencing PH. Regular reviews provide the opportunity to screen for potential complications and reduce the time in the harness [23,61,68]. A recent systematic review suggested weekly or 2 weekly examinations with US in harness [27].…”

What’s New in Pediatric Orthopaedics

“…Residual dysplasia at 1 year of age was detected in 17% of patients in the 12-week group compared with 11% of patients in the 6-week group (p = 0.189). The authors concluded that the first routine follow-up ultrasound can be safely accelerated from 12 to 6 weeks after harness initiation 73 . The impact of Pavlik harness weaning was evaluated and, although they had longer total harness time, infants treated with Pavlik weaning, compared with those who were not weaned, did not demonstrate different radiographic results at 1 year of age 74 .…”

Active monitoring versus immediate abduction as treatment of stable developmental dysplasia of the hip: a systematic review of the literature

“… 6 15 Currently, abduction treatment is the most opted DDH treatment in children younger than 6 months. 16 However, it is debatable whether abduction treatment alters the natural course of stable hips. 6 A study by Pollet et al did not find a difference in acetabular development between abduction treatment and active monitoring in infants with stable hips at the age of 3 to 4 months.…”