Article Text

Original research
Active monitoring versus immediate abduction as treatment of stable developmental dysplasia of the hip: a systematic review of the literature
  1. Evy M B Paulussen1,
  2. Frederike E C M Mulder1,
  3. Nina M C Mathijssen2,
  4. M Adhiambo Witlox3
  1. 1Department of Orthopaedic Surgery, Maastricht University, Maastricht, The Netherlands
  2. 2Department of orthopaedic surgery, Reinier Haga Orthopedic Center, Zoetermeer, The Netherlands
  3. 3Department of Orthopaedic Surgery, Maastricht University Medical Centre+, Maastricht, The Netherlands
  1. Correspondence to Evy M B Paulussen; evypaulussen{at}


Objectives This systematic review aims to compare the effects of active monitoring and abduction treatment on the Graf alpha angle, Acetabular Index (AI) and femoral head coverage in infants with stable developmental dysplasia of the hip (DDH).

Design Systematic review reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Data sources A search of the PubMed, Embase, Cochrane and Web of Science databases was performed in January 2020 and updated in January 2021.

Eligibility criteria (Non-)randomised studies comparing active monitoring with abduction treatment in infants younger than 4 months with stable DDH were included.

Data extraction and synthesis All eligible articles were methodologically assessed using the Cochrane risk of bias tools. Data were extracted by summarising the study characteristics and results.

Results Of the six included studies, two randomised studies were of low risk and two of some concerns. Two non-randomised studies were of serious risk. In total, 544 dysplastic hips (439 infants) were investigated, of which 307 were observed and 237 were treated. Two studies reported a faster improvement of the alpha angle and average acetabular coverage in treated hips at 3 months. No differences in AI between the treatment and observation group after 3 months were reported. In total, 38 infants (12%) in the observation group switched to the treatment group. At the final radiograph, 21 observed hips and 32 treated hips were dysplastic.

Conclusions There were no differences in AI between the treatment and observation group after 3 months in infants up to 4 months of age with stable DDH hips. The switch of 38 infants (12%) from the observation to the treatment group corroborates that not all infantile DDH hips will spontaneously progress into normal hips. The small study population sizes and methodological heterogeneity warrant a large randomised controlled trial to study this research question.

PROSPERO registration number CRD4202123300.

  • paediatric orthopaedics
  • hip
  • diagnostic radiology

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

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Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

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  • EMBP and FECMM contributed equally.

  • Contributors NMCM and MAW were involved in the study design and developed the search string; EMBP, NMCM and MAW performed the literature search, extracted data and performed the risk of bias analysis. All authors read and approved the final manuscript and were involved in writing the manuscript. EMBP and FECMM contributed equally to this paper. MAW is responsible for the overall content of this article as guarantor.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.