The use of X-ray at 5 months in a selective screening programme for developmental dysplasia of the hip

Concentric Circles: A New Ultrasonographic Sign for the Diagnosis of Normal Infantile Hip Development

Ultrasound (US) of the infant hip is used to diagnose developmental dysplasia of the hip (DDH). We present a new sonographic sign that describes the periphery of the femoral head and the acetabulum as two concentric circles.During 2008−2019, 3650 infants were referred for diagnosis of DDH. All underwent a clinical and US examination. We recorded the femoral head as the inner circle, within a fixed external circle, which was identified as the acetabulum. We analysed the clinical signs and risk factors. The US sign of two concentric circles was normal in 3522 infants and was classified as normal hip development. The alpha angle was >60° in 3449 (95%) infants. For the remaining 73 (5%) infants, the alpha angle was 50−60° and underwent further follow-up examination until the alpha angle was normalised. In 128 babies (3.5%), we detected the disruption of the concentric circle sign; the femoral head was found outside the acetabulum, which appeared with an upward sloping roof and the alpha angle was <50°. These infants had DDH and received appropriate treatment. Infants with a concentric circle sign and normal alpha angle are normal, whereas those with a disrupted sign are considered as having DDH.

Diagnostic Performance of a New Convolutional Neural Network Algorithm for Detecting Developmental Dysplasia of the Hip on Anteroposterior Radiographs

OBJECTIVE

To evaluate the diagnostic performance of a deep learning algorithm for the automated detection of developmental dysplasia of the hip (DDH) on anteroposterior (AP) radiographs.

MATERIALS AND METHODS

Of 2601 hip AP radiographs, 5076 cropped unilateral hip joint images were used to construct a dataset that was further divided into training (80%), validation (10%), or test sets (10%). Three radiologists were asked to label the hip images as normal or DDH. To investigate the diagnostic performance of the deep learning algorithm, we calculated the receiver operating characteristics (ROC), precision-recall curve (PRC) plots, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and compared them with the performance of radiologists with different levels of experience.

RESULTS

The area under the ROC plot generated by the deep learning algorithm and radiologists was 0.988 and 0.988-0.919, respectively. The area under the PRC plot generated by the deep learning algorithm and radiologists was 0.973 and 0.618-0.958, respectively. The sensitivity, specificity, PPV, and NPV of the proposed deep learning algorithm were 98.0, 98.1, 84.5, and 99.8%, respectively. There was no significant difference in the diagnosis of DDH by the algorithm and the radiologist with experience in pediatric radiology (p = 0.180). However, the proposed model showed higher sensitivity, specificity, and PPV, compared to the radiologist without experience in pediatric radiology (p < 0.001).

CONCLUSION

The proposed deep learning algorithm provided an accurate diagnosis of DDH on hip radiographs, which was comparable to the diagnosis by an experienced radiologist.

A normal screening ultrasound does not provide complete reassurance in infants at risk of hip dysplasia; further follow-up is required

BACKGROUND

Screening for developmental hip dysplasia (DDH) continues to evolve with the use of ultrasound (US) in either selective or universal screening methods. The possibility of delayed evidence of DDH, and thus the need for radiographic follow-up at a later stage of development have been suggested by some authors.

AIMS

The aim of this review was to evaluate the number of patients in our hospital network with a normal screening US at 6 weeks with evidence of DDH at the time of radiographic review at 6 months. Secondary aim; to determine the outcomes for these patients.

METHODS

A retrospective review was done to infants undergoing DDH ultrasound screening between January and December 2015. Initial US and radiographs at 6 months were reviewed. Patients with normal screening US who had subsequent radiographs were included for analysis.

RESULTS

In total, there were 829 patients included for analysis. Sixty-three patients (8%) had evidence of DDH at 6 months, representing 34% of all DDH diagnoses for the study period. Five of the 63 patients were lost to follow-up. The remaining 58 babies were treated in Boston bracing. Four patients with evidence of persistent DDH were referred for tertiary review. The osteotomy rate in the radiograph diagnosed group was 2%, versus 6% and 3% in the unstable and US diagnosed groups, respectively.

CONCLUSION

Eight percent of patients with a normal screening US had evidence of DDH at time of radiograph at 6 months, reflecting 34% of all our DDH cases for the year. Based on these findings, patients in our hospital network undergo radiographic evaluation at 6 months even if the initial screening US is normal.

Value of the 'clicky hip' in selective screening for developmental dysplasia of the hip

AIMS

The aim of this study was to review the value of accepting referrals for children with 'clicky hips' in a selective screening programme for hip dysplasia.

PATIENTS AND METHODS

A single-centre prospective database of all referrals to the hip clinic was examined to identify indication for referrals, diagnosis, and treatment. All patients referred received a standardized ultrasound scan and clinical examination by an orthopaedic consultant.

RESULTS

There were 5716 children referred to the orthopaedic hip clinic between 1 June 2014 and 26 September 2018. In all, 1754 children (30.1%) were referred due to 'clicky hip' with no additional risk factors or indications for ultrasound scan. A total of 123 children (7.1%) referred with 'clicky hip' and no additional risk factors or examination findings had an abnormal initial hip ultrasound, including 16 children (0.9%) with dysplastic hips. Of the 141 children who required treatment in a Pavlik harness during the study period, 23 (16%) had been referred with a 'clicky hip' and no additional risk factors or examination findings, including six children with Graf 3 or 4 hips.

CONCLUSION

There is significant value in reviewing children with an isolated 'clicky hip'. Many children who require treatment are referred to the orthopaedic service as 'clicky hip' with no additional risk factors. In a pragmatic pathway with a diverse population of clinicians performing baby checks, 'clicky hip' is an important indication for referral and should not be discarded. Cite this article: Bone Joint J 2019;101-B:635-638.

The most relevant diagnostic criteria for developmental dysplasia of the hip: a study of British specialists

Background

Developmental dysplasia of the hip (DDH) is the most common orthopaedic disorder in newborns. Despite this considerable variation in practice exists. The aim of this study was to determine the clinical relevance and a ranking order for the diagnostic criteria in DDH amongst paediatric orthopaedic surgeons practicing in the UK.

Method

One hundred members of the British Society of Children’s Orthopaedic Surgery (BSCOS) were asked to rate the importance of 37 criteria useful in the diagnosis of DDH in newborns, using a 10 cm visual analogue scale. We determined the consistency among specialists in rating the criteria with the intraclass correlation coefficient (ICC) and compared the results to a group of international peers.

Results

Ortolani/Barlow tests, asymmetry in abduction ≥20° and a first-degree relative treated for DDH ranked among the top ten. Participants demonstrated poor consistency in rating the 37 criteria (ICC 0.39; 95 % CI 0.29, 0.52), but for clinical examination criteria alone their consistency improved (ICC 0.52; 0.35, 0.75). The importance ratings of members of BSCOS and members of the European Paediatric Orthopaedic Society differed for 15/37 (41 %) criteria (p <0.05).

Conclusions

Members of BSCOS had a preference for criteria relating to clinical examination and ultrasound.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-0867-4) contains supplementary material, which is available to authorized users.

Do we need to follow up an early normal ultrasound with a later plain radiograph in children with a family history of developmental dysplasia of the hip?

BACKGROUND

We routinely perform a pelvic radiograph between 6 and 12 months of age for children with a family history of developmental dysplasia of hip (DDH). We conducted this study to determine whether children with a family history of DDH and a normal hip ultrasound after birth require any further radiological follow-up.

METHODS

We identified all children referred to our hip-screening clinic in a 3-year period between August 2008 and August 2011 with a family history of DDH and a normal hip ultrasound after birth. A total of 119 patients with a normal hip ultrasound after birth had a pelvic radiograph at a median age of 6.6 months.

RESULTS

Six patients had residual dysplasia (acetabular index >30°) on the initial radiograph; five of these had resolved spontaneously by age 12 months, and the remaining patient had a normal radiograph at 21 months of age and was discharged.

CONCLUSION

We have found no cases of residual hip dysplasia requiring treatment in children with a family history of DDH and a normal hip ultrasound after birth. We have therefore changed our practice accordingly and no longer routinely followed up such cases.

LEVEL OF EVIDENCE

Diagnostic study, Level II.

Current screening recommendations for developmental dysplasia of the hip may lead to an increase in open reduction

Most centres in the United Kingdom adopt a selective screening programme for developmental dysplasia of the hip (DDH) based on repeated clinical examination and selective ultrasound examination. The Newborn Infant Physical Examination protocol implemented in 2008 recommends a first examination at birth and then a second and final examination at six to ten weeks of age. Due to concerns over an increase in late presentations we performed a retrospective review of our 15-year results to establish if late presentation increases treatment requirements. Of children presenting before six weeks of age, 84% were treated successfully with abduction bracing, whereas 86% of children presenting after ten months eventually required open reduction surgery. This equates to a 12-fold increase in relative risk of requiring open reduction following late presentation. Increasing age at presentation was associated with an increase in the number of surgical procedures, which are inevitably more extensive and complex, with a consequent increased in cost per patient. The implementation of an opportunistic examination at three to five months could help to reduce the unintended consequences of the Newborn Infant Physical Examination programme.