Examining the Short-Term Natural History of Developmental Dysplasia of the Hip in Infancy: A Systematic Review

Intraoperative 3D Fluoroscopy During Open Reduction for DDH: An Effective Alternative to Postoperative CT/MRI

BACKGROUND

Computed tomography CT or magnetic resonance imaging (MRI) has been the most used imaging modality to assess hip reduction in developmental dysplasia of the hip (DDH) after open reduction (OR). In 2015, intraoperative 3D fluoroscopy (3D) was introduced at our center as an alternative to CT/MRI. 3D offers the advantage that if hip reduction is insufficient, it can be addressed at the time of surgery. The purpose of this study was to assess the efficacy of 3D in comparison to CT/MRI.

METHODS

This was a single-centre, retrospective comparative study of two consecutive cohorts: those with OR and 3D between 2015 and 2017 and those with OR and CT/MRI between 2012 and 2014. Time to imaging, re-imaging, length of stay (LOS), re-operation, and redislocation or subluxation after cast removal were evaluated.

RESULTS

Forty-two patients (46 hips) had 3D, and 30 patients (32 hips) had CT/MRI. Significant differences were found between groups in time to imaging, cast changes, and LOS. All 3D was intraoperative (46 hips), and only 69% (22 hips) of CT/MRI was on the day of surgery ( P <0.01). In the 3D group, 1 hip (2%) had a cast change under the same anesthetic, and 4 hips (13%) from CT/MRI had cast changes in subsequent surgery ( P =0.03). The mean LOS in days for 3D was 1.72 and 2.20 for CT/MRI ( P =0.03). There were no statistically significant differences between groups in further imaging and subluxations or re-dislocations at cast removal. Two hips (4%) in the 3D group had MRI, but with no further intervention ( P =0.51), and at cast removal, there were 3 subluxations in each group ( P =0.69) and 1 redislocation in the 3D group ( P =1.00).

CONCLUSIONS

Intraoperative 3D improved time to imaging, allowed for cast changes at surgery and had a shorter LOS. Moreover, there were no significant differences found in adverse outcomes between those who underwent 3D versus CT/MRI. 3D should thus be considered an effective alternative to CT/MRI for assessing hip reduction during OR for DDH.

LEVEL OF EVIDENCE

Diagnostic Study, level II.

Using an Innovative Model to Improve Performance of the Infant Hip Examination

OBJECTIVES

Determine if a new teaching bundle targeting developmental dysplasia of the hip screening improved interns' examination skills across multiple pediatric residency programs.

METHODS

This multicenter prospective cohort study included interns across 6 pediatric residency sites within the Academic Pediatric Association's Better Outcomes through Research for Newborns Network in 2022. Participants underwent a baseline hip examination assessment on models using a checklist derived from textbook descriptions of Galeazzi, Ortolani, and Barlow maneuvers before receiving a teaching bundle. Repeat testing occurred after instruction. Data were analyzed using t-test for continuous and χ2 test for categorical variables. Semistructured focus groups provided qualitative feedback regarding the teaching bundle.

RESULTS

We enrolled 117 of 155 interns across 6 sites (76%) for participation in the teaching bundle. Only 2% of participants (n = 2) identified a positive Galeazzi sign at baseline, whereas 88% (n = 103, P < .001) did so on the postinstructional assessment. Although 27% of participants (n = 32) correctly identified a positive Barlow sign at baseline, 69% (n = 81, P < .001) did so on the postinstructional assessment. The ability to correctly detect a positive Ortolani sign increased from 22% (n = 26) to 92% (n = 108, P < .001). Fifteen interns participated in the semistructured focus groups, with resultant themes reinforcing the limited experience of the infant hip examination before this intervention and the positive impact of the teaching bundle.

CONCLUSIONS

Most participants in this study did not have strong infant hip examination skills at entry into residency. A standardized teaching bundle significantly improved skills in examination technique and identifying abnormalities.

Comparison of brace to observation in stable, radiological developmental dysplasia of the hip: a protocol for a global multicentre non-inferiority randomised trial

INTRODUCTION

Brace treatment is common to address radiological dysplasia in infants with developmental dysplasia of the hip (DDH); however, it is unclear whether bracing provides significant benefit above careful observation by ultrasound. If observation alone is non-inferior to bracing for radiological dysplasia, unnecessary treatment may be avoided. Therefore, the purpose of this study is to determine whether observation is non-inferior to bracing for infants with radiological dysplasia.

METHODS AND ANALYSIS

This will be a multicentre, global, randomised, non-inferiority trial performed under the auspices of a global prospective registry for infants and children diagnosed with DDH. Patients will be included if they present with radiological dysplasia (centred hip, alpha angle 43-60°, percent femoral head coverage greater than 35% measured on ultrasound) of a clinically stable hip under 3 months old. Patients will be excluded if they present with clinical hip instability, have received prior treatment or have known/suspected neuromuscular, collagen, chromosomal or lower-extremity congenital abnormalities or syndromic-associated hip abnormalities. Patients will be enrolled and randomised to undergo observation alone or brace treatment with a Pavlik harness for a minimum of 6 weeks. Follow-up visits will occur at 6 weeks, 1 year and 2 years post-enrolment. The primary outcome will be the norm-referenced acetabular index measured on the 2-year radiograph with a 3° non-inferiority margin. A total of 514 patients will be included.The study is anticipated to start in April 2024 and end in September 2028.The primary outcome will be compared between arms with a mixed-effects model with a random intercept for study centre, and a single covariate for the treatment group. If the lower bound of the 95% CI lies within 3° of the mean, we will treat this as evidence for non-inferiority.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the lead site's ethics board (University of British Columbia, Children's and Women's Research Ethics Board). Ethics approval will be obtained from the local ethics committees or institutional review boards at each institution prior to patient enrolment. It is intended that the results of this study shall be published in peer-reviewed journals and presented at suitable conferences.

TRIAL REGISTRATION NUMBER

NCT05869851.

Developmental Dysplasia of the Hip: Controversies in Management

PURPOSE OF REVIEW

Many aspects of developmental hip dysplasia (DDH) care and evaluation are still active areas of debate. Recent studies have provided more insight into these topics such as strategies for reducing osteonecrosis, assessing hip reduction after closed and open reduction, and the management of residual acetabular dysplasia.

RECENT FINDINGS

The presence of the ossific nucleus at the time of reduction does not alter the risk of osteonecrosis. The risk of osteonecrosis may be higher when hips are immobilized in excessive abduction. Limited sequence MRI may be the best choice for assessing hip reduction after closed and open reduction; however, new technologies are emerging such as 3D fluoroscopy and perfusion MRI. The treatment of residual acetabular dysplasia with bracing has been shown to be effective and the decision to perform a pelvic osteotomy is based on patient-specific factors. The spectrum of DDH treatment has evolved over the past several decades. Recent studies have provided insights into strategies for osteonecrosis prevention, hip evaluation during after reduction, and the management of residual acetabular dysplasia. However, there is ample room for additional and more rigorous studies guiding advanced imaging for assessing hip reduction such as 3D fluoroscopy and perfusion MRI, as well as the management of residual acetabular dysplasia.