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Background: DDH is 1 of the most important causes of childhood disability. A diagnosis of instability can be made in the neonatal period via the Ortolani and Barlow manoeuvres. However, clinical examination, although highly specific, has poor sensitivity as compared to ultrasound. There is controversy between the necessity of universal screening for dysplasia of all newborns or selective screening reserved for those with clinical signs of instability or known risk factors of DDH., Aim: To analyse the risk factors of congenital hip dysplasia in a consecutive case series of children referred for diagnosis and treatment of DDH., Materials and Methods: This was a cross-sectional study on infants consecutively examined between January 2000 and December 2019 at the Marino Ortolani Centre in Ferrara, Italy. The first 3 types on Graf's classification were considered physiological (1A, 1B, 2A+), while the last 6 pathological (2A-, 2B, 2C, 2D, 3, 4)., Results: 18,954 infants met the inclusion criteria and were therefore considered eligible for the study. Of these 18,954 infants, 56% ( n  = 10,629) were females and 44% ( n  = 8325) were males. According to Graf classification, 34.9% ( n  = 6621) were 1A, 52.7% ( n  = 9999) were 1B, 4.0% ( n  = 753) were 2A+, 2.5% ( n  = 478) were 2A-, 1.5% ( n  = 284) were 2B, 1% ( n  = 196) were 2C, 1.3% ( n  = 243) were 2D, 1% ( n  = 193) were 3 and 1.0% ( n  = 187) were 4. The most significant risk factor was the female gender (OR 5.36; 95% CI, 4.63-6.20) followed by a family history (OR 2.35; 95% CI, 2.08-2.65), then skeletal pathologies (OR 2.04; 95% CI, 1.21-3.42), oligohydramnios (OR 1.75; 95% CI, 1.44-2.13), and finally breech presentation (OR 1.42: 95% CI, 1.27-1.60)., Conclusions: Based on our data, family history, musculoskeletal disease, oligohydramnios and breech presentation are the main risk factors for DDH development, as is the female sex., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

This study aims to assess whether or not the nationwide newborn ultrasonographic hip screening program has influenced the rate of different types of surgical interventions performed in developmental dysplasia of the hip (DDH) in children in Turkey. A retrospective analysis of the nationwide data obtained from the National Registry System between January 1, 2015, and December 31, 2020, was carried out. The rate of minor and major surgical interventions was calculated by dividing the total number of primary closed/open reductions with or without tenotomies and the total number of primary pelvic or periacetabular osteotomies with or without femoral osteotomies by the total number of live births in the country per year, respectively. The rates of primary minor surgical interventions were found to be 0.47/1000 in 2015, 0.71/1000 in 2016, 1.07/1000 in 2017, 1.00/1000 in 2018, 1.06/1000 in 2019, and 0.89/1000 in 2020. The rates of primary major surgical intervention were found to be 0.74/1000 in 2015, 0.40/1000 in 2016, 0.33/1000 in 2017, 0.31/1000 in 2018, 0.32/1000 in 2019, and 0.21/1000 in 2020. The introduction of the nationwide newborn hip screening program has significantly changed the surgical treatment modalities in children with DDH. A nearly twofold increase in the rate of primary closed/open reduction and hip spica casting and nearly three quarters decrease in the rate of primary bony procedures were observed within 6 years., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The long-term radiological outcomes after the treatment of neonatal hip instability (NHI) in developmental dysplasia of the hip are unclear. Therefore, the prevalence of acetabular dysplasia at a mean age of 18 years after treatment was investigated. The relationship between acetabular dysplasia and hip discomfort has also been poorly established. Therefore, the differences in pain, hip-related quality of life (QOL), and hip impingement tests in hips with and without acetabular dysplasia were assessed., Methods: All 127 patients treated for NHI from 1995 to 2001 at the study hospital and meeting the inclusion criteria were invited to participate in this population-based follow-up. Of these individuals, 88 (69.3%) participated. The lateral center-edge angle (LCEA), Sharp's angle (SA), and acetabular head index (AHI) were calculated for both hips from pelvic anterior-posterior radiographs. The Copenhagen Hip and Groin Outcome Score (HAGOS) questionnaire was completed for both hips separately; the total score, pain, and QOL subscores were calculated; and the impingement test was performed., Results: The prevalence of acetabular dysplasia, defined as an LCEA <20°, was 3.4%. Only the mean AHI (81.1%, SD 5.3) differed (-5.08, 95% CI -5.77 to -4.38, P <0.001) from previously described gender-specific and side-specific means, whereas the mean LCEA and SA did not. The odds ratio for a positive hip impingement test was 2.8 (95% CI: 1.11-7.05, P = 0.029) for hips with an LCEA <25° compared to hips with LCEA ≥25°. The hips with an SA ≥45° had a mean of 7.8 points lower for the HAGOS pain subscore (95% CI: 4.2-11.4, P <0.001) and a mean of 6.1 points lower for the HAGOS QOL subscore (95% CI: 2.1-10.2, P = 0.003) compared with hips with an SA <45°., Conclusions: The prevalence of acetabular dysplasia was low after treatment for NHI. Acetabular dysplasia seems to be as common in the general population as for those treated for NHI based on the LCEA. Only an SA ≥45° resulted in slightly more pain and lower hip-related QOL., Competing Interests: M.M. received personal working grants for this research from the Finnish Foundation for Pediatric Research, the Finnish Research Foundation for Orthopaedics and Traumatology, The Päivikki and Sakari Sohlberg Foundation, and The Alma and K. A. Snellman Foundation, Oulu, Finland. The remaining authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The incidence of developmental dysplasia of the hip (DDH) in Japanese newborns has reduced drastically following a primary prevention campaign initiated around 1972 to 1973; this perinatal education campaign promoted maintaining the hips of newborns in the naturally flexed-leg position. The purpose of the present study was to describe the life course epidemiology of hip osteoarthritis (OA) in adolescent and adult patients and to assess its association with exposure to the primary prevention campaign for DDH., Methods: We included new patients with hip OA diagnosed from January 1, 2022, to December 31, 2022, at 12 core hospitals (8 special-function hospitals and 4 regional medical care support hospitals). The trend in the percentage of hips with a history of DDH treatment in childhood was estimated with use of a centered moving average using the birth year of the patient. We compared the prevalence of severe subluxation (Crowe type II, III, or IV) between patients with secondary hip OA due to hip dysplasia who were born in or before 1972 and those who were born in or after 1973., Results: Overall, 1,095 patients (1,381 hips) were included. The mean age at the time of the survey was 63.5 years (range, 15 to 95 years). A total of 795 patients (1,019 hips; 73.8% of hips) were diagnosed with secondary OA due to hip dysplasia. Approximately 13% to 15% of hips among patients born from 1963 to 1972 had a history of DDH treatment in childhood; however, the percentage decreased among patients born in or after 1973. The prevalence of severe subluxation (Crowe type II, III, or IV) among patients born in or after 1973 was 2.4%, which was significantly less than that among patients born in or before 1972 (11.1%; odds ratio, 0.20; p < 0.001)., Conclusions: As of 2022, secondary hip OA due to hip dysplasia is still responsible for most new cases of adolescent and adult hip OA seen in core hospitals in Japan. However, the perinatal education campaign initiated 50 years ago, which utilized a population approach and advocated for maintaining the hips of newborns in the naturally flexed-leg position, may have improved the environmental factors of DDH, as indicated by the apparently reduced need for treatment of DDH in childhood and the associated severe subluxation. This may result in a reduced need for challenging hip surgery later in life., Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: This work was supported by the Japan Society for the Promotion of Science (KAKENHI) (grant JP23K08654). The Article Processing Charge for open access publication was funded by the Japan Society for the Promotion of Science (KAKENHI) (grant JP23K08654). The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H969 )., (Copyright © 2024 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)

Importance: Delayed diagnosis of a dislocated hip in infants can lead to complex childhood surgery, interruption to family life, and premature osteoarthritis., Objective: To evaluate the diagnostic accuracy of clinical examination in identifying dislocated hips in infants., Data Sources: Systematic search of CINAHL, Embase, MEDLINE, and the Cochrane Library from the inception of each database until October 31, 2023., Study Selection: The 9 included studies reported the diagnostic accuracy of the clinical examination (index test) in infants aged 3 months or younger and a diagnostic hip ultrasound (reference test). The Graf method of ultrasound assessment was used to classify hip abnormalities., Data Extraction and Synthesis: The Rational Clinical Examination scale was used to assign levels of evidence and the Quality Assessment of Diagnostic Accuracy Studies tool was used to assess bias. Data were extracted using the individual hip as the unit of analysis; the data were pooled when the clinical examinations were evaluated by 3 or more of the included studies., Main Outcomes and Measures: Sensitivity, specificity, and likelihood ratios (LRs) of identifying a dislocated hip were calculated., Results: Among infants screened with a clinical examination and a diagnostic ultrasound in 5 studies, the prevalence of a dislocated hip (n = 37 859 hips) was 0.94% (95% CI, 0.28%-2.0%). There were 8 studies (n = 44 827 hips) that evaluated use of the Barlow maneuver and the Ortolani maneuver (dislocate and relocate an unstable hip); the maneuvers had a sensitivity of 46% (95% CI, 26%-67%), a specificity of 99.1% (95% CI, 97.9%-99.6%), a positive LR of 52 (95% CI, 21-127), and a negative LR of 0.55 (95% CI, 0.37-0.82). There were 3 studies (n = 22 472 hips) that evaluated limited hip abduction and had a sensitivity of 13% (95% CI, 3.3%-37%), a specificity of 97% (95% CI, 87%-99%), a positive LR of 3.6 (95% CI, 0.72-18), and a negative LR of 0.91 (95% CI, 0.76-1.1). One study (n = 13 096 hips) evaluated a clicking sound and had a sensitivity of 13% (95% CI, 6.4%-21%), a specificity of 92% (95% CI, 92%-93%), a positive LR of 1.6 (95% CI, 0.91-2.8), and a negative LR of 0.95 (95% CI, 0.88-1.0)., Conclusions and Relevance: In studies in which all infant hips were screened for developmental dysplasia of the hip, the prevalence of a dislocated hip was 0.94%. A positive LR for the Barlow and Ortolani maneuvers was the finding most associated with an increased likelihood of a dislocated hip. Limited hip abduction or a clicking sound had no clear diagnostic utility.

Objective: To investigate whether there is a relationship between the 2nd finger and 4th finger length measurement ratios and developmental dysplasia of the Hip (DDH)., Study Design: Cross-sectional observational study. Place and Duration of the Study: Department of Orthopaedics and Traumatology, Meram Faculty of Medicine Hospital, Konya, Turkiye, from January 2020 to May 2023., Methodology: Infants were screened for DDH with Graff method for the ultrasounds of both hips. Lengths of the 2nd and 4th fingers of both hands were measured and recorded. Patients with additional risk factors for developmental dysplasia of the hip (breech birth, family history, oligohydramnios, swaddling) were excluded., Results: Two hundred and fifty-six babies were screened including 55.1% (n = 141) girls and 44.9% (n = 115) boys. Their mean age was 2.51 ± 0.80 months. The average lengths were 31.73 ± 3.05 mm, for the left 2nd finger and 34.26 ± 3.48 mm for the left 4th finger. In the hip USG measurements, the mean alpha angles were 62.91 ± 3.12° for the right hip and, 63.20 ± 3.55° for the left hip. Eighteen (7%) of babies who underwent hip ultrasound (USG) had unilateral or bilateral DDH. Among these cases, 2.7% (n = 7) had right, 2.3% (n = 6) had left, and 2% (n = 5) had bilateral DDH. There was no statistically significant correlation between the ratios of right 2/4 finger lengths and the right alpha angle (rs = 0.051; p = 0.421). There was a statistically positive and statistically significant correlation between the ratios of left 2/4 finger lengths and the left alpha angle (rs = 0.154; p = 0.013)., Conclusion: Only the left-hand finger ratio among the parameters in the model had a statistically significant effect on DDH. Therefore, the left hand 2D/4D finger length may be of value in screening for DDH., Key Words: Developmental dysplasia of the hip, Second to fourth finger digit ratio, Ring finger, Digit ratios.

Objective: The UK falls behind other European countries in the early detection of developmental dysplasia of the hip (DDH) and screening strategies differ for early detection. Clinical detection of DDH is challenging and recognised to be dependent on examiner experience. No studies exist assessing the number of personnel currently involved in such assessments.Our objective was to review the current screening procedure by studying a cohort of newborn babies in one teaching hospital and assess the number of health professionals involved in neonatal hip assessment and the number of examinations undertaken during one period by each individual., Methods: This was a retrospective observational study assessing all babies born consecutively over a 14-week period in 2020. Record of each initial baby check was obtained from BadgerNet. Follow-up data on ultrasound or orthopaedic outpatient referrals were obtained from clinical records., Results: 1037 babies were examined by 65 individual examiners representing 9 different healthcare professional groups. The range of examinations conducted per examiner was 1-97 with a median of 5.5 examinations per person. 49% of individuals examined 5 or less babies across the 14 weeks, with 18% only performing 1 examination. Of the six babies (0.48%) treated for DDH, one was picked up on neonatal assessment., Conclusion: In a system where so many examiners are involved in neonatal hip assessment, the experience is limited for most examiners. Currently high rates of late presentation of DDH are observed locally, which are in accordance with published national experience. The potential association merits further investigation., Competing Interests: Competing interests: No, there are no competing interests., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

This study is an observation of the early screening and treatment effect of infant developmental dysplasia of the hip (DDH) in an area in China. From January 2016 to December 2017, we selected infants and toddlers with high-risk factors for DDH, such as asymmetric gluteal folds, unequal length of lower limbs, and limited hip joint abduction, who visited the Department of Child Health Care and the Outpatient Clinic of Pediatric Orthopedics at the Affiliated Hospital of Zunyi Medical University. In total, 1485 cases were divided into age groups, examined using Graf ultrasound and X-ray, and the results were analyzed. Meanwhile, early interventions were actively adopted for cases with abnormalities during the screening. The detection rates of DDH were 24.0%, 2.8%, 9.3%, and 12.2% among those with 0 to 6 months, 7 to 12 months, 13 to 18 months, and 19 to 24 months of age, respectively. Early and individualized corrective conservative treatment was considered for children with abnormalities, and the cure rates were 87.0%, 65.7%, 41.0%, and 16.7% among those with 0 to 6 months, 7 to 12 months, 13 to 18 months, and 19 to 24 months of age, respectively. There was a statistically significant difference in the detection and cure rates of DDH in infants and toddlers of different ages (P < .01)., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Developmental hip dysplasia is an abnormality of the hip joint which is associated with an unstable or dislocatable hip. During infancy, hips should be screened to determine whether they are stable, unstable or dislocated. In Australia, this screening is often performed by nurses using physical assessment. Physical examination includes a number of assessments which seek to identify underlying abnormalities in hip joint anatomy and function. This scoping review outlines the physical assessments used by nurses in the screening and surveillance of developmental hip dysplasia. A review of the literature identified 15 ( N = 15; 100%) sources of evidence, which included original research articles ( n = 6; 40%), expert opinion pieces ( n = 2; 13.3%) and practice guidelines ( n = 7; 46.7%). There were 18 physical assessments identified as being used by nurses in the screening process for developmental hip dysplasia. However, it is apparent that high quality research is required to examine the timing, specificity and sensitivity of the physical assessments identified., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Developmental dysplasia of the hip (DDH) affects 1-3% of newborns and 20% of cases are bilateral. The optimal surgical management strategy for patients with bilateral DDH who fail bracing, closed reduction or present too late for these methods to be used is unclear. There are proponents of both medial approach open reduction (MAOR) and anterior approach open reduction (AOR); however, there is little evidence to inform this debate., Methods: We will perform a systematic review designed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol. We will search the medical and scientific databases including the grey and difficult to locate literature. The Medical Subject Headings "developmental dysplasia of the hip", "congenital dysplasia of the hip", "congenital hip dislocation", "developmental hip dislocation", and their abbreviations, "DDH" and "CDH" will be used, along with the qualifier "bilateral". Reviewers will independently screen records for inclusion and then independently extract data on study design, population characteristics, details of operative intervention and outcomes from the selected records. Data will be synthesised and a meta-analysis performed if possible. If not possible we will analyse data according to Systematic Review without Meta-Analysis guidance. All studies will be assessed for risk of bias. For each outcome measure a summary of findings will be presented in a table with the overall quality of the recommendation assessed using the Grading of Recommendations Assessment Development and Evaluation approach., Discussion: The decision to perform MAOR or AOR in patients with bilateral DDH who have failed conservative management is not well informed by the current literature. High-quality, comparative studies are exceptionally challenging to perform for this patient population and likely to be extremely uncommon. A systematic review provides the best opportunity to deliver the highest possible quality of evidence for bilateral DDH surgical management., Systematic Review Registration: The protocol has been registered in the International Prospective Register of Systematic Reviews (PROSPERO ID CRD42022362325)., (© 2024. Crown.)

Developmental dysplasia of the hip (DDH) is a common hip disorder in infants. Ultrasonographic screening is considered the most reliable method for early detection of DDH in newborn infants. This study aimed to determine the incidence of DDH at King Abdulaziz University Hospital. From January 2017 to December 2018, this retrospective study analyzed the data of 8031 infants who underwent an early clinical examination of the hips. At the initial evaluation, 212 infants referred to the ultrasound department had risk factors for DDH and/or clinical instability. Different well-known risk factors of DDH have been identified including breech position, skeletal deformities, positive family history, hip side, sex and clicky hip. The findings revealed an incidence rate of 93 cases of DDH among 8031 infants (11.58 per 1000) births. Among the infants diagnosed with DDH, 55 were females (59.14 %), and 38 were males (40.86%). The results of the current study revealed that 45% of infants with DDH exhibited bilateral involvement. Moreover, results showed that the IIa hip joint was more prevalent in female than in male newborns, but without any significant difference. The incidence rate of DDH in this study was 11.58 per 1000 live births, and it was more prevalent among female than male newborns. Ultrasonography (US) should be used as a complementary imaging modality for clinical examination of DDH. Infants with breech presentation, clicky hip, and skeletal deformity should be scanned by US. Further prospective studies are recommended., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Purpose: Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal disorder in infants. The most significant risk factors include female gender, breech presentation, left hip and family history. In this study, we utilized the Graf method at different time intervals to evaluate both breech-delivered and cephalic-born newborns. The objectives were to compare the incidence of DDH in cephalic and breech-delivered neonates and investigate whether the hip joints of neonates delivered in the breech position exhibit a distinct maturation pattern., Material and Methods: We studied prospectively 618 hip joints (309 newborns). Each hip joint was examined with the Graf method in four time periods as follows: Phase #1 (0-1 weeks), Phase #2 (1-4 weeks), Phase #3 (4-7 weeks), and Phase #4 (7-10 weeks). The α and β angles for each hip joint were measured, and the hips were classified according to Graf classification. With our statistical analysis within the different phases, we were able to investigate potential variations in the maturation patterns between newborns delivered in the breech and cephalic delivery positions., Results: A significant difference (at the 5% level) was observed in Phase 1 between breech and cephalic-delivered neonates (35.6-8.6%). This difference tended to decrease in next phases (13.6-1% in Phase 2, 2.5-0% in Phase 3 and 1.7-0% in Phase 4). A significant difference (at the 5% level) for cephalic-delivered neonates was also observed between Phase 1 and Phase 4 (8.5-0%), but the percentages were low. Additionally, the breech-delivered had extreme difference in incidence of DDH from Phase 1 to Phase 4 (35.6-11.9%, 2.5%, and 1.7%, respectively)., Conclusion: It appears that there is an actual difference in the incidence of DDH between breech-delivered and cephalic-delivered neonates, although the difference may be less significant than previously considered. The majority of the breech-delivered neonates that were initially considered as pathological (Phase 1) are, in fact, healthy. This is ascertained in subsequent ultrasound examinations conducted in later phases (Phases 2-4), when the incidence of pathological cases decreases. This could be attributed to potential different maturation pattern between these groups., (© 2023. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Coxa Magna (CM) is defined as a condition in which the horizontal (transverse) diameter of the femoral head is larger on the affected side than on the intact side. CM can occur as a manifestation of avascular necrosis (AVN) following treatment for the developmental dysplasia of the hip (DDH). Alternatively, it can also be secondary to other hip disorders, such as Perthes' disease. This study aimed to determine the prevalence and indicators of CM and AVN of the femoral head that can be detected during follow-up in patients with unilateral DDH treated with closed reduction (CR) or open reduction (OR) surgery. The files of 143 patients treated for unilateral DDH between January 1997 and December 2017 were reviewed retrospectively. A total of 104 patients, including Group 1 ( n = 49) patients who underwent CR under general anesthesia and Group 2 ( n = 55) patients who underwent OR were included in the study. CM; It was considered as the case where the femoral head was 15% or more larger than the intact side. A total of 104 patients were followed up for 77.27 ± 13.96 months, with a mean age of 15.43 ± 7.76 months. When Group 1 and Group 2 were compared, there was no statistical difference in terms of sex, side, adductor tenotomy, and AVN ( P > 0.05). CM developed in 22.4% ( n = 11) of the patients in Group 1 and in 49.1% ( n = 27) in Group 2, and the difference was statistically significant ( P = 0.008). When the effect of independent variables on the development of CM is evaluated with the multivariate logistic regression model, the risk of developing CM is 3474 times higher in those who underwent iliopsoas tenotomy compared with those who did not. The primary outcome of this study is that CM is more frequent in patients treated with OR for DDH. CM may be a nonpathological condition that occurs in connection with iliopsoas tenotomy or surgical treatment. Prospective studies with a larger number of cases, designed to minimize confounding factors, are required., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: An initial screening ultrasound is essential for patients at higher risk of developmental dysplasia of the hip (DDH) due to breech presentation or a family history of DDH. The American Academy of Pediatrics recommends screening ultrasounds to be performed after 6 weeks of age to reduce the rate of false positives. However, there is limited evidence regarding whether these screening ultrasounds need to be adjusted for gestational age in prematurity. The purpose of this study was to evaluate the influence of moderate preterm and near-term births on screening hip ultrasounds for high-risk DDH populations., Methods: We identified all prospectively enrolled patients in a single-center database referred for screening hip ultrasound for DDH. We included those hips referred for risk factors of DDH, including breech presentation, family history of DDH, or hip click, and excluded those with known dysplasia or referral for hip instability. Each ultrasound was measured by a pediatric radiologist to determine the alpha angle and femoral head coverage. Patients were classified as "premature" if born at <37 weeks gestation or "full term" if born at ≥37 weeks gestation. All patients underwent screening hip ultrasound between 5 and 8 weeks of age. Sonographic markers of dysplasia and the incidences of abnormal ultrasound and Pavlik harness treatment were compared between cohorts. Significance was set at P <0.05., Results: A total of 244 hips in 122 patients were included, 58 hips in the premature cohort and 186 hips in the full-term cohort. The premature cohort had a significantly decreased gestational age compared with the full-term cohort (35.4 ± 1.1 vs 38.5 ± 1.1 wk, respectively, P < 0.001). However, there was no difference between premature and full-term cohorts in sex distribution (69% vs 75%, females, P = 0.39), unadjusted age at the time of ultrasound (6.6 ± 0.7 vs 6.8±0.7 wk, respectively, P = 0.07), or referral reason ( P = 0.14). On hip ultrasound, there was no difference between premature and full-term cohorts with respect to alpha angle (62.6 ± 3.3 vs 62.2 ± 5.3 degrees, P = 0.41), femoral head coverage (54.9 ± 6.3 vs 55.1 ± 10.6, P = 0.19), rate of abnormal ultrasound (18.3% vs 20.7%, respectively, P = 0.68), or the rate of Pavlik harness treatment (0% vs 5.3%, respectively, P = 0.12)., Discussion: There was no significant difference in alpha angle or femoral head coverage between premature and full-term patients at 5 to 8 weeks of unadjusted age. This preliminary data suggests that screening ultrasounds can be performed without adjusting for prematurity., Level of Evidence: Level II, prognostic study., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background and Purpose: There is inconsistency in the literature regarding the relationship between increased birthweight and risk of developmental dysplasia of the hip (DDH). We aimed to investigate the correlation between birthweight and pubo-femoral distance (PFD), as well as Graf's α angle in newborns undergoing hip ultrasound examination at 6 weeks of age., Patients and Methods: Basic newborn characteristics and ultrasound measurements were retrospectively collected during a 1-year study period. We excluded multiple births, newborns born at less than 37 gestational weeks, and incomplete information. Simple and multiple linear regression analyses were performed to evaluate the correlation of birthweight and PFD, and, second, birthweight and α angles including a stratified regression analysis investigating the potential effect modification of sex., Results: 707 newborns (1,414 hips) were included. Mean birthweight was significantly higher for male newborns (P < 0.001). Increased birthweight was positively correlated to PFD values (crude coefficient 0.21, 95% confidence interval [CI] 0.10-0.32) and the correlation was still present after adjusting for sex, family history, and breech presentation (adjusted coefficient 0.18, CI 0.07-0.29). The stratified α angle model for the males was significant for both the crude coefficient (-0.73, CI -1.28 to -0.19) and the adjusted (-0.59, CI -1.15 to -0.03), and also for the females (crude coefficient -1.14, CI -1.98 to -0.31 and adjusted coefficient -1.15, CI -1.99 to -0.31)., Conclusion: We found that increased birthweight positively correlated to PFD, and negatively correlated to α angle, but this was not of clinical significance.

Background and Purpose: We aimed to establish the incidence of late-detected developmental dysplasia of the hip (DDH) with a selective ultrasound (US) examination over 17 years using the femoral head coverage (FHC) as a US measurement. The secondary aim was to establish the everyday function using patient-reported outcome measures (PROMs)., Patients and Methods: The incidence of late-detected DDH was based on 60,844 children. Patients diagnosed for the first time after 3 months and before the age of 8 years were included. In the second part of the study, consent to participate was mandatory. PROMIS-25 Pediatric, PROMIS-25 Parent, and EQ-5D-5L were used according to the patient's age to assess everyday function., Results: The incidence of late-detected DDH was 0.48/1,000. The median age at diagnosis was 8 months (range 4-41 months), with a tendency to require repeated treatment with open surgery if DDH was diagnosed later. Most children reported no or minor health problems with a mean of 18 years' follow-up., Conclusion: We found that selective US examination of the hips by measuring the FHC is a reliable method to examine newborns for DDH resulting in a low incidence of late-detected DDH amounting to 0.48/1,000 newborn children.

Developmental dysplasia of the hip (DDH) is commonly addressed through surgical intervention, usually performed in a specialized tertiary care facility. The purpose of this study was to evaluate the surgical outcomes in patients with DDH who had open reduction alone or in conjunction with bone surgery at our facility. We retrospectively reviewed the medical records of patients with DDH, categorizing them into two groups: Group OR underwent open reduction (OR) alone, and group ORBO underwent OR in conjunction with femoral or pelvic osteotomies. The modified McKay classification was used to evaluate clinical outcomes, and the Severin classification was used to evaluate radiological outcomes. Avascular necrosis and other postoperative issues were observed. Our cohort consisted of 66 patients (76 hips), with a mean age at surgery of 1.8±2.6 and a follow-up period ranging from one to three years. Clinically, 48 out of 66 patients achieved satisfactory outcomes, and radiologically, 47 patients were classified as satisfactory. Although there was no statistically significant difference in the radiological outcome (P=0.85), more patients in the OR group than in the ORBO group (P=0.05) had better outcomes. Avascular necrosis (AVN) was observed in 23 hips (34.8%), with Grade I AVN being the most prevalent in 19 hips that underwent OR with bone surgery (63.2%). The occurrence of AVN was associated with poorer clinical and radiological outcomes (P=0.05). Overall, the DDH operation at our center had positive outcomes. The OR group showed better clinical outcomes despite similar radiological findings and AVN rates compared to the OR with bone surgery group. The presence of AVN was linked to poor clinical and radiological outcomes., Competing Interests: The authors declare no conflict of interest., (© 2023 The Author(s).)

Competing Interests: Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests Provenance and peer review: Commissioned; externally peer reviewed.

Competing Interests: Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests Provenance and peer review: Commissioned; externally peer reviewed.

Objectives: To investigate if the incidence of developmental dysplasia of the hip (DDH) differs considering the geographical origin, clinical picture, or presence of risk factors in homogenous cohort of neonates born in Mediclinic Al Jowhara hospital, Al Ain, United Arab of Emirates (UAE)., Methods: Universal ultrasonography hips screening of the neonates in the maternity ward of Mediclinic Al Jowhara hospital, Al Ain, UAE, was carried out using the Graf method. The average age of the neonates was 3 days. Two groups were formed for comparison: I) the Gulf Cooperation Council (GCC) group (n=169, 47.7%), and II) the non-GCC group (n=185, 52.3%)., Results: The incidence of DDH was 1.7%. It was higher among neonates from the GCC region (2.9%) and significantly higher among girls from this region (6.3%). The incidence of immature hips (type IIa) was 9% and was similar regardless of origin or gender., Conclusion: Neonates from the GCC region, girls in particular, have a higher incidence of DDH. These results highlight the emergency to establish a national ultrasonography DDH screening program., (Copyright: © Saudi Medical Journal.)

Introduction: Adolescent idiopathic scoliosis radiographic screening will often include the hips. The purpose of this study is to evaluate the prevalence of hip dysplasia by lateral center edge angle (LCEA) on scoliosis radiographs in patients presenting with severe range (>45 deg) idiopathic curves., Methods: We reviewed 200 consecutive patients (400 hips) with idiopathic scoliosis with major coronal curves ≥45 degrees between October 2009 and October 2022. The presenting scoliosis radiograph PA were reviewed for the following variables: major coronal curve direction, coronal balance, and lateral center edge angles. An LCEA value ≤18 was considered dysplastic. To assess potential measurement variability related to parallax of the scoliosis radiographs, the intermodality intraclass correlation coefficient (ICC) was measured from a subset of 20 hip LCEA values from patients with both scoliosis and pelvis radiographs., Results: A total of 200 patients [mean age: 13.6 (1.8) years; Female: 79%] were reviewed. The mean major curve (SD) was 58.6 degrees (11.4 deg). Overall 19% (37/200) patients or 11% (43/400) of hips had hip dysplasia. Of the dysplastic hips, 16% (6/43, P <0.001) were bilateral and 57% (21/43, P =0.04) were right sided. There was no association between dysplastic hip laterality and ipsilateral or contralateral coronal balance ( P =0.26) or curve direction ( P =0.49). The interobserver ICC for assessment of LCEA on scoliosis radiographs was 0.85, and the intermodality ICC between pelvic and scoliosis radiographs was 0.78., Conclusion: Hip dysplasia was present in 19% of patients presenting with large major curves, and many of these patients had right sided hip dysplasia. There was no association between hip dysplasia laterality and the patient's major curve direction or coronal balance. There was good intermodality reliability (ICC=0.78) between LCEA values in patients who had both scoliosis and pelvis radiographs, and good inter-rater reliability between raters. Radiographic interpretation of adolescent idiopathic scoliosis should focus not only on the description of the curve and ruling out underlying segmentation anomalies but should also include critical assessment of the hips to exclude co-existing hip dysplasia., Level of Evidence: Therapeutic study-level IV., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To estimate the prevalence of developmental dysplasia of the hip (DDH) in infants with a systematic review and meta-analysis., Method: A literature search was conducted in April 2023, using databases such as Cochrane Library, PubMed, MEDLINE, CNKI, and SinoMed, without language restrictions. Eligible studies included cross-sectional studies reporting the prevalence of DDH among infants aged 0-12 months. Two independent reviewers manually selected and coded the studies, with any disagreements resolved by a third reviewer. Meta-analysis was performed using a random-effects model to calculate the prevalence of DDH. Regression analysis examined the trend of DDH prevalence, and stratification analysis explored heterogeneity between studies., Results: A total of 65 studies involving 3 451 682 infants were included in the meta-analysis. None of the studies were classified as high quality, four were medium-to-high quality, 50 were low-to-medium quality, and eight were low quality. The pooled prevalence of DDH was 1.40% (95% CI: 0.86 to 2.28, I 2 =100%), and prevalence of dysplasia, subluxation, and dislocation was 1.45% (95% CI: 0.93 to 2.24, I 2 =97%), 0.37% (95% CI: 0.22 to 0.60, I 2 =94%), and 0.21% (95% CI: 0.13 to 0.34, I 2 =92%), respectively. Notably, the overall prevalence has a slight upward trend in the last three decades (β=0.24, p=0.35), but the dysplasia was downward trend (β=-0.48, p<0.01). Girls have higher risk of DDH than boys (1.46% vs 0.66%; Q=5.83, df=1, p=0.02). There were no significant differences based on gender, country, setting, or screening technique., Conclusion: The prevalence of DDH among infants is approximately one in a 100, with girls being at higher risk. Though the prevalence of dysplasia has decreased, there is a slight upward trend in overall DDH. Therefore, routine screening for DDH in infants is recommended to prevent more serious developmental problems., Competing Interests: Competing interests: None., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The purpose of this study was to evaluate the rate of residual acetabular dysplasia (RAD), defined as an acetabular index (AI) of >90th percentile of age and sex-matched controls, in a cohort of infants successfully treated with the Pavlik harness (PH)., Methods: We retrospectively studied typically developing infants at a single center, with at least 1 dislocated hip, that was successfully treated with a PH and had a minimum of 48 months follow-up. Hip dislocation was defined as <30% femoral head coverage at rest on pretreatment ultrasound or IHDI grade 3 or 4 on the pretreatment radiograph., Results: Forty-six dislocated hips (41 infants) were studied (4 males and 37 females). Brace treatment was initiated at an average age of 1.8 months (range: 2 d to 9.3 mo) and was maintained for an average of 10.2 months (range: 2.3 to 24.9 mo). All hips achieved IHDI grade 1 reduction. Five of 46 hips (11%) had an AI >90th percentile at the conclusion of bracing. Average follow-up was 6.5 years (range: 4.0 to 15.2 y). We found a 30% incidence of RAD (14/46 hips) on final follow-up radiographs. Of these hips, 13/14 (93%) had AI <90th percentile at the end of brace treatment. Comparing children with and without RAD, there were no differences in age at the initial visit or brace initiation, total follow-up, femoral head coverage at the initial visit, alpha angle at the initial visit, or total time in the brace ( P > 0.09)., Conclusion: In a single-center cohort of infants with dislocated hips treated successfully with a PH, we observed a 30% incidence of RAD at a minimum 4.0-year follow-up. Normal acetabular morphology at the end of brace treatment did not result in normal acetabular morphology at the final follow-up in 13/41 hips (32%). We recommend that surgeons should pay close attention to the year-over-year change in both the AI and AI percentile., Level of Evidence: Level IV: case series., Competing Interests: C.S.P. has the following disclosures: Alphatec Spine: Stock or stock Options. OrthoPediatrics: Stock or stock Options. Stryker: Stock or stock Options. V.V.U. has the following disclosures: Daedalus Medical Solutions, Inc.: Employee. DePuy, A Johnson & Johnson Company: Paid consultant. Imagen: Stock or stock Options. Indius: Unpaid consultant. nView: Research support. Orthofix, Inc.: Paid consultant. OrthoPediatrics: IP royalties; Paid consultant; Research support. Pacira: Paid consultant. Stryker: Paid consultant. Wolters Kluwer Health - Lippincott Williams & Wilkins: Publishing royalties, financial or material support. ZimVie: Research support. The remaining author declares no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Different screening strategies for developmental dysplasia of the hip (DDH) exist. Despite screening efforts, cases of late presentation continue to occur, often necessitating surgery. This systematic review and meta-analysis assess the effect of newborn selective ultrasound screening for DDH on the incidence of late presentation in infants and children, compared to a universal ultrasound strategy. A systematic search across Medline and EMBASE databases was performed between January 1950 and February 2021. A consensus-based evaluation of abstracts led to retrieval of relevant full text, original articles or systematic reviews in English only. These were assessed according to agreed eligibility criteria, and their reference lists were reviewed to identify additional eligible publications. Following final consensus on included publications, data was extracted, analysed and reported as per PRISMA and Prospero (CRD42021241957) guidelines. The 16 eligible studies consisted of 2 randomised controlled trials and 14 cohort studies, published between 1989 and 2014, with a total of 511,403 participants. In total, 121,470 (23.8%) received a neonatal hip ultrasound, of whom 58,086 and 63,384 were part of a selective or a universal ultrasound screening strategy, respectively. The difference in the proportion of late presentation between the universal and selective strategies was 0.0904 per 1,000 (P = 0.047). The time effect, i.e. the difference between early and late presentation defined respectively, as less than and more than 3 months of age, regardless of screening strategy, was not significant (P = 0.272). Although there was variability in study design and reporting, the quality of the evidence, based on the critical appraisal skills programme appraisal tools, was generally good. Compared to universal ultrasound screening for DDH, selective screening resulted in a slightly higher rate of late presentation. Uniformity in design and reporting of DDH studies and a cost-effectiveness analysis are needed., (© 2023. The Author(s).)

Objective: This study aimed to identify the relevance of hospitalizations for congenital hip deformities in Bahia., Methods: This is a retrospective epidemiological study in public databases. Descriptors in health sciences: "congenital hip dysplasia", "congenital hip dislocation", and "congenital dislocation hip". This is qualitative-quantitative research with the analysis of secondary data and cross-sectional typologies in the databases of the Ministry of Health - Health Information (TABNET), made available by the Department of Informatics of the Unified Health System (DATASUS)., Results: Bahia was the third Brazilian state with the highest number of hospitalizations, registering 1481 cases. The municipalities in Bahia with the highest prevalence were Itanhém, Salvador, and Barreiras, with 912, 445, and 20 cases, respectively., Conclusions: The elevated number of congenital hip deformities reflects a public health problem, requiring investments in public policies.

Some patients with developmental dysplasia of the hip (DDH) before 6 months of age successfully treated by Pavlik Harness (PH) still had persistent acetabular dysplasia (PAD). This study aimed to investigate the incidence and risk factors for PAD in patients with DDH treated by PH. We retrospectively reviewed the data of 89 patients (109 hips; mean age, 3.2 ± 1.5 months) with DDH treated by PH. Prior to treatment, all patients underwent ultrasound examination and classified according to Graf's method. PH was terminated once the hip achieved imaging recovery criteria. At final follow-up, the acetabular index (AI), center-edge angle (CEA) of Wiberg were measured on radiograph. Overall, 67/109 hips (61.5%) had successful PH treatment. Among these 67 hips, 58 hips (86.6%) achieved satisfactory outcome, nine (13.4%) had PAD. Age of the patients with PAD (4.3 ± 1 months) was significantly higher than those without PAD (2.8 ± 1.5 months) ( P = 0.001). Hips with PAD had higher mean Graf grade than those with satisfactory outcome ( P = 0.014). Logistic regression-confirmed age and Graf classification were risk factors for PAD. Overall, 55/67 (82.1%) met imaging recovery criteria to stop PH treatment, whereas 12/67 hips (17.9%) did not. The rate of PAD at final follow-up in patients achieving recovery criteria (4/55; 7.3%) was significantly lower than those not achieving it (41.7%) ( P = 0.007). In conclusion, age and Graf classification are risk factors for PAD. If hips are not normal at the end of PH treatment, the risk of PAD increases further., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Developmental dysplasia of the hip (DDH) is the most common orthopedic disorder in newborns. Early recognition and diagnosis are critical to prevent long-term complications. While several risk factors have been established, the association between prematurity and DDH remains unclear. Our analysis sought to analyze the literature exploring the relationship between prematurity and DDH. Articles evaluating the relationship between prematurity and DDH published between 1 January 2000 and 1 February 2022 were queried, with 11 studies included for analysis. Overall, a total of 8720 patients were included. The gestational age ranged from 23 to 36 weeks for preterm and ≥37 weeks for term births. Seven studies agreed that gestational age did not have a significant impact on DDH. Pooled analysis of available data demonstrated no significant difference in DDH among preterm and term infants (OR, 1.11; 95% CI, 0.82-1.51; P  = 0.49). Sub-group analysis of two studies reporting data on very preterm (≤32 weeks) and term infants revealed no significant difference in the occurrence of DDH (OR, 4.58; 95% CI, 0.09-244.78; P  = 0.45). Four studies found early gestational age is associated with a significantly higher incidence of mature hips compared to late preterm or term babies. Similarly, pooled analysis demonstrated significantly lower Graf classification among preterm infants (OR, 0.13; 95% CI, 0.03-0.61; P  = 0.009). Based on the current literature, our analysis found that prematurity is not strongly associated with DDH. Furthermore, early gestational age was associated with a significantly higher incidence of mature hips measured by Graf classification., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The prevalence of developmental dysplasia of the hip (DDH) has been considered to be low in East Asia, but this may be incorrect because of inconsistent diagnostic definitions and testing criteria. In 2015, the AAOS released guidelines for systematic screening for DDH in newborns. We implemented these guidelines and compared DDH incidence and outcomes before and after their implementation., Methods: We used a historic comparison cohort of newborns with DDH between July 2015 and May 2017 before guideline implementation (the preguideline group); their data were retrieved using electronic medical records. In this group, the newborns received general hip screening without systemic follow-up. The postguideline group included newborns who were screened for hip dysplasia and followed up per the AAOS guidelines between July 2017 and May 2019. Their data were prospectively collected. The primary outcome in the postguideline group was DDH incidence. Other outcomes included rates of referral, surgery, and complications, and DDH prognosis., Results: The preguideline and postguideline groups included 3534 and 2663 newborns, respectively, of whom 49 (1.1%) and 225 (8.4%), respectively, were referred to the pediatric orthopaedic clinic enrolled. In the postguideline group, 35 patients were diagnosed as having DDH (incidence: 1.3%, 95% CI: 0.8%-1.9%). Both the incidence and referral rates were significantly higher in the postguideline group than in the preguideline group. Furthermore, the mean age at referral was 6.7±10.06 months and 0.9±0.25 months in the preguideline and postguideline groups, respectively, indicating a potential for early treatment in the postguideline group. Finally, the female sex was identified as a risk factor for residual hip dysplasia at 6 months of age., Conclusion: DDH incidence in East Asia seems comparable to that in Western countries. Implementing the AAOS guidelines increased the diagnosis rate and opportunity for early treatment initiation, thus potentially avoiding surgical intervention. Nevertheless, residual DDH may be detected in some patients at 6 months of age, particularly in female infants., Level of Evidence: Level IV., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: To investigate risk factors of misdiagnosis at the first visit of children with developmental dysplasia of the hip (DDH) who did not participate in hip ultrasound screening., Methods: A retrospective review was conducted on children with DDH admitted to a tertiary hospital in northwestern China between January 2010 and June 2021. We divided the patients into the diagnosis and misdiagnosis groups according to whether they were diagnosed at the first visit. The basic information, treatment process and medical information of the children were investigated. We made a line chart of the annual misdiagnosis rate to observe the trend in the annual misdiagnosis rate. Univariate and multivariate logistic regression analyses were used to identify significant risk factors for missed diagnosis., Results: A total of 351 patients met the inclusion criteria, including 256 (72.9%) patients in the diagnosis group and 95 (27.1%) patients in the misdiagnosis group. The line chart of the annual rate of misdiagnoses among children with DDH from 2010 to 2020 showed no significant change trend. Multiple logistic regression analysis showed that the paediatrics department ( v the paediatric orthopaedics department: OR 0.21, p<0.001), the general orthopaedics department ( v the paediatric orthopaedics department: OR 0.39, p=0.006) and the senior physician ( v the junior physician: OR 2.47, p=0.006) on the misdiagnosis at the first visit of children were statistically significant., Conclusion: Children with DDH without hip ultrasound screening are prone to be misdiagnosed at their first visit. The annual misdiagnosis rate has not been significantly reduced in recent years. The department and title of the physician are independent risk factors for misdiagnosis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The purpose of this systematic review was to appraise the literature on the association between preterm birth and developmental dysplasia of the hip (DDH)., Methods: Medline, Embase, Scopus, and Web of Science databases were queried for all studies pertaining to DDH and preterm birth. Data were imported and analyzed in Revman5 and Comprehensive Meta-Analysis (CMA) for pooled prevalence estimation., Results: Fifteen studies were included in the final analysis. There were 759 newborns diagnosed with DDH in these studies. DDH was diagnosed in 2.0% [95%CI:1.1-3.5%] of the premature newborns. Pooled incidence rate of DDH was not statistically different between those groups (2.5%[0.9%-6.8%] vs. 0.7%[0.2%-2.5%] vs. 1.7%[0.6%-5.3%];Q = 2.363,p = 0.307)., Conclusions: In this systematic review and meta-analysis, we did not find preterm birth to be a significant risk factor for DDH. Data suggests that female sex and breech presentation are associated with DDH in preterm infants, but the data is scarce in the literature., (© 2023. The Author(s).)

Background & Objectives: Developmental dysplasia of the hip (DDH), when detected early, can usually be managed effectively by simple methods. A delayed diagnosis often makes it a complex condition to treat. Late presentation of DDH is fairly common in developing countries, and there is scarcity of literature regarding the epidemiology and reason for late presentation. Through this study, we attempted to identify the reasons for late presentation of DDH in children more than 12 months of age., Methods: Fifty four children with typical DDH and frank dislocation of hip in whom treatment was delayed for 12 months or more were included. Parents were interviewed with a pre-structured questionnaire and data were collected for analysis with Microsoft Excel 2016 and SPSS version 26., Results: Diagnostic delay was the most common reason for late presentation and was observed in 52 children (96.2%). The mean age at diagnosis was 24.7 months. The mean age at treatment was 37.3 months with a mean delay of 12.5 months from diagnosis and 22.1 months from initial suspicion. Physician-related factors contributed 55.3 per cent, while family and social issues accounted for 44.7 per cent of overall reasons for diagnostic and treatment delays., Interpretation & Conclusions: Late presentation of DDH in walking age is common. Physician- and family-related factors accounted for most of these cases. Failure or inadequate hip screening at birth by the attending physician is a common reason for late diagnosis. The family members were unaware about the disorder and developed suspicion once child started walking with an abnormal gait.

Background: The prevalence of hip dysplasia among patients with Down syndrome (DS) is higher than in the general population. We hypothesize that a relationship may exist between functional level and hip dysplasia in DS, but this has not been studied to date. The aim of this study is to evaluate whether there is a relationship between functional level and radiographic parameters of hip dysplasia or other measures., Methods: Retrospective cross-sectional comparative study of 652 patients with DS from a pediatric referral center database. Patients over 8 years of age with an anteroposterior pelvis radiograph and with no exclusion criteria were selected, totaling 132 patients (264 hips; 54.55% females; mean age 12.96 ± 2.87 y). Several radiographic parameters of the acetabulum [Sharp angle (SA), Tönnis angle (TA), Wiberg center-edge angle (W-CEA), extrusion index (EI), and acetabular retroversion signs], the proximal femur [neck shaft angle (NSA)], and joint congruence [Shenton line (SL)] were assessed. Patients were classified into 2 levels based on functional skills. A multivariate association analysis was performed between radiographic parameters and functional level., Results: Sixty-one patients were compatible with a functional level I and 71 with a level II. Forty-six hips were dysplastic and 60 were borderline according to the W-CEA. A statistically significant relationship was found between the categorical distribution of certain radiographic measurements of hip dysplasia (EI, SA, TA, W-CEA, SL, and classification by functional level ( P < 0.0005). A significant receiver operating characteristic curve was obtained for W-CEA with a cutt-off point at 26.4 degrees for level I (area under the curve = 0.763; P < 0.005; sensitivity = 0.800 and specificity = 0.644). There was a fairly high correlation between EI and TA (0.749; P < 0.0005), EI and W-CEA (-0.817; P < 0.0005), and TA and W-CEA (-0.748; P < 0.0005). Numerous hips showed signs of acetabular retroversion, with no significant differences found between functional levels or association with hip dysplasia measures., Conclusions: The present study reveals a relationship between an increased risk of hip dysplasia and reduced functional levels in DS children older than 8 years. These findings may guide individualized clinical follow-up of hip development in DS children considering their functional level., Level of Evidence: Level III, retrospective comparative study., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Developmental dysplasia of the hip (DDH) is a cluster of hip development disorders that affects infants. The incidence of DDH-related dislocation (DDH-dislocation) is reportedly 0.1-0.3%; however, the nationwide incidence of DDH-dislocation in Japan has not been previously reported. The primary aim of this study was to report the nationwide incidence of DDH-dislocation in Japan using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), and to examine its regional variation across Japan., Methods: This was a retrospective birth cohort study using the NDB. Data on patients born between 2011 and 2013 and assigned DDH-dislocation-related disease codes during 2011-2018 were extracted. Among these, patients who underwent treatment for DDH-dislocation between 2011 and 2018 were defined as patients with DDH-dislocation., Results: Across the 2011, 2012, and 2013 birth cohorts, 2,367 patients were diagnosed with DDH-dislocation, yielding the nationwide incidence of 0.076%. Region-specific incidence rates were almost similar across Japan. Secondary analyses revealed that 273 (11.5%) patients were diagnosed at the age of ≥1 year. The effect of birth during the cold months on the incidence of DDH-dislocation was significant (relative risk [RR] = 1.89, 95% confidence interval [CI]: 1.75-2.06). The risk of DDH-dislocation among girls was approximately seven times higher than that among boys., Conclusion: This is the first study to report the nationwide incidence of DDH-dislocation in Japan, which was estimated at 0.076%. The regional variation was trivial and unlikely to be clinically significant. Thus, the incidence rates were approximately equal across all regions in Japan.

Developmental dysplasia of the hip (DDH) is the main cause of early-onset hip osteoarthritis in adulthood. Early screening of DDH is the key to avoiding these severe complications. This study aimed to assure the risk factors are suitable for screening patients with DDH in our region. We retrospectively analyzed 10,668 patients (21,336 hips) at our hospital. Overall, 204 patients with pathological DDH and 408 patients with normal hips were included in this study. All patients were diagnosed by performing ultrasound examinations according to the Graf technique. The risk factors were assessed based on patients' clinical data. Pearson's chi-square or Fisher's exact tests and multivariate logistic regression analysis were performed for statistical analysis. A total of 204 patients were diagnosed with pathologic DDH and were treated with the Pavlik harness. Among these, 184 patients were female. There were 73 cases of first birth, 13 had oligohydramnios, 13 had foot deformity, 31 had breech delivery, 6 had congenital muscular torticollis. Female sex, vaginal delivery, breech presentation, oligohydramnios and foot deformity were identified as the risk factors for DDH. The risk factors of DDH in our clinical center were confirmed in our clinical center, this can supply the screening advice for the doctors., (© 2022. The Author(s).)

Objective: To investigate the effect of coronavirus disease 2019 restrictions on ultrasound (US) screening of developmental dysplasia of the hip (DDH) in a children's hospital., Methods: The records of US screening of DDH were retrospectively evaluated in the pandemic period (April 2020 to July 2021) and the pre-pandemic period (January 2019 to February 2020). The monthly US number, sex, radiologist number, and age at the initial examination were recorded., Results: A total of 6107 US scans were performed during the pre-pandemic period, which significantly decreased to 3340 during the pandemic. The number of monthly US scans performed did not change between the pre-pandemic (142.7/month) and pandemic (128.2/month) periods. The number of delayed examinations in the total population did not significantly change between the two periods. However, the number of delayed examinations in patients with abnormal hips was significantly increased during the pandemic compared with that in the pre-pandemic period., Conclusions: Coronavirus disease 2019 restrictions decreased the US screening rate of DDH by almost half, but the number of US scans performed by each radiologist was unchanged. The compliance with follow-up recommendations was reduced by half, which may lead to an increase in the incidence of delayed and untreated DDH cases.

Congenital Hip Dysplasia (CHD) is characterized by a hip joint dislocation between the femoral head and the acetabulum, with a multifactorial etiology. This disorder can be an isolated condition or the manifestation of a syndromic condition, and it has been estimated with higher rates than registered, with a predominance in female sex and left side; risk factors are now defined. In Italy, the incidence rate is 3-4%, with significant regional differences: higher in Lombardy and lower in Sicily. Because clinical examination alone is insufficient to diagnose CHD, it is supplemented with ultrasonography and X-ray if necessary. Surveillance, static or dynamic splints, or osteotomies are the only treatment options. The goal of this study was to evaluate our experience in terms of management and conservative treatment of all newborns from January 2018 to May 2022: female sex and left hip were major involved, risk factors were not significant in our case, but results from early diagnosis and treatments, in terms of better outcome, were interesting. After a strict 6-month follow-up period, 89.13% of the patients were classified as grade Ia or Ib according to the Graf classification system. Finally, we emphasize the importance of early universal screening and subsequent diagnosis to allow for early treatment of the disorder, at an age when conservative treatments can yield good results.

Developmental dysplasia of the hip (DDH) is a debilitating condition that affects 1-7% of newborns. Children with DDH, not treated early and effectively, will easily lead to disability. A better understanding of the biology of DDH is critical to the development of prognostic biomarkers and novel therapies. The purpose of this study was to establish a biobank of DDH genetic resources, to facilitate clinical and basic scientific research. The biological specimen and clinical data of DDH were collected in Shanghai Children's Hospital from 2014 to 2021. The collection of blood samples was performed at definitive diagnosis and review, tissue specimens were performed at definitive surgery. The clinical data was collected at the whole stage of DDH patients at diagnosis, treatment and follow-up. A total of 528 patients with DDH were enrolled in this study, 90 were men and 438 were women, with the mean age of 4.67 years. The numbers of tissue and blood specimens reached 2172 and 1490, respectively. The quality test results showed that the DNA concentration decreased slightly with the extension of storage time, but the DNA purity did not change. Meanwhile, the extension of storage time slightly affected the stability of protein of tissue samples but did not affect the expression of the housekeeping gene. The DDH biobank built has the potential of monitoring disease pathogenesis and progress, which could provide specimens to the researchers improving the biological understanding and provide guidance of clinical treatment of this disease to clinicians., (© 2022. The Author(s).)

Background and Objectives: Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal conditions in children. If not treated, it leads to disability, gait abnormalities, limb shortening, and chronic pain. Our study aims to determine the impact of multiple risk factors on the incidence of DDH and to develop an interactive risk assessment tool. Materials and Methods: We conducted a retrospective cohort study in the Outpatient Clinic for Children of the Medical University of Warsaw Hospital. The Graf classification system was used for universal ultrasonographic screening. In total, 3102 infants met the eligibility criteria. Results: The incidence of DDH in the study group was 4.45%. The incidence of DDH in the Warsaw population, Poland, during the study period was 3.73 to 5.17 (95% CI). According to the multivariate analysis, the risk factors for DDH were birth weight (OR = 2.17 (1.41−3.32)), week of delivery (OR = 1.18 (1.00−1.37)), female sex (OR = 8.16 (4.86−13.71)), breech presentation (OR = 5.92 (3.37−10.40)), physical signs of DDH (25.28 (8.77−72.83)) and positive family history in siblings (5.74 (2.68−12.31)). Our results support the recent hypothesis that preterm infants (<37 weeks) have a lower rate of DDH. Conclusions: A multivariate logistic regression predictive model was used to build the risk calculator. The DDH risk calculator will be evaluated in a prospective validation study.

Justification: When developmental dysplasia of the hip (DDH) is diagnosed during infancy, conservative management is often successful, with good long-term outcomes. In India, DDH is often not diagnosed until walking age and there are limited guidelines for its screening., Process: A multidisciplinary Expert Group consisting of members of the Paediatric Orthopaedic Society of India, Indian Academy of Pediatrics, National Neonatology Forum of India, Indian Radiological and Imaging Association, Indian Federation of Ultrasound in Medicine and Biology, Federation of Obstetric and Gynaecological Societies of India, and Indian Orthopaedic Association worked collaboratively to develop surveillance guidelines for DDH., Objectives: To enhance the early detection rate of DDH in India through development and implementation of a standardized surveillance care pathway, thus reducing the burden of late-presenting DDH., Recommendations: Routine clinical hip examinations must be performed on all infants at birth and during immunization visits at these approximate time points: 6, 10, and 14 weeks; 6, 9, 12, 15, and 18 months of age. Assessments include Ortolani and Barlow tests for infants <14 weeks; limited hip abduction and leg length discrepancy for infants >14 weeks; and evaluation of limp in walking children. If clinical examination is abnormal or inconclusive, referral to orthopedics for further evaluation and management is recommended. In infants younger than 6 weeks with positive Barlow test but negative Ortolani test, hip ultrasound is recommended at 6 weeks of age. Infants must also be screened for DDH risk factors: breech presentation, family history of DDH, unsafe hip swaddling, and hip instability at any previous clinical examination. In infants with risk factors but normal clinical examination, further evaluation should include ultrasound taken no earlier than 6 weeks of age for infants younger than 14 weeks, ultrasound or X-ray for infants 14 weeks to 6 months of age, and X-ray for infants older than 6 months. Referral to an orthopedic surgeon is recommended if radiological tests are abnormal.

Importance: Universal ultrasonographic screening for developmental dysplasia of the hip (DDH) has gained increasing popularity despite the lack of benefit in terms of reducing the rates of late-detected cases (age ≥12 weeks) in randomized clinical trials., Objective: To report the reported incidence of DDH in the English scientific literature and compare rates of late-detected cases in settings with different DDH screening strategies., Data Sources: PubMed, Scopus, and Web of Science databases were searched on November 25 and 27, 2021. No time filters were used in the search., Study Selection: All observational studies reporting the incidence of early-detected or late-detected (age ≥12 weeks) DDH were included. Non-English reports were excluded if the abstract did not include enough information to be included for analysis., Data Extraction and Synthesis: The number of newborns screened and the detection rates were extracted. Meta-analysis calculated the pooled incidence of DDH per 1000 newborns with 95% CIs using a random- or fixed-effects model. This study is reported according to the PRISMA and MOOSE guidelines., Main Outcomes and Measures: The main outcome measures were early detection, early treatment, late detection, and operative treatment incidences., Results: A total of 1899 studies were identified, 203 full texts were assessed, and 76 studies with 16 901 079 infants were included in final analyses. The early detection rate was 8.4 (95% CI, 4.8-14.8) infants with DDH per 1000 newborns with clinical screening, 4.4 (95% CI, 2.4-8.0) infants with DDH per 1000 newborns with selective ultrasonographic screening, and 23.0 (95% CI, 15.7-33.4) infants with DDH per 1000 newborns with universal ultrasonographic screening. Rates for nonoperative treatment were 5.5 (95% CI, 2.1-14) treatments per 1000 newborns with clinical screening, 3.1 (95% CI, 2.0-4.8) treatments per 1000 newborns with selective ultrasonographic screening, and 9.8 (95% CI, 6.7-14.4) treatments per 1000 newborns with universal ultrasonographic screening. The incidence of late-detected DDH was 0.5 (95% CI, 0.2-1.5) infants with DDH per 1000 newborns with clinical screening, 0.6 (95% CI, 0.3-1.3) infants with DDH per 1000 newborns with selective ultrasonographic screening, and 0.2 (95% CI, 0.0-0.8) infants with DDH per 1000 newborns with universal ultrasonographic screening. The corresponding incidences of operative treatment were 0.2 (95% CI, 0.0-0.9) operations per 1000 newborns with clinical screening, 0.5 (95% CI, 0.4-0.7) operations per 1000 newborns with selective ultrasonographic screening, and 0.4 (95% CI, 0.2-0.7) operations per 1000 newborns with universal ultrasonographic screening., Conclusions and Relevance: This meta-analysis found that early detection rates and nonoperative treatments were higher with universal screening. The late detection and operative treatment rates with universal screening were similar to those among selectively and clinically screened newborns. Based on these results, universal screening may cause initial overtreatment without reducing the rates of late detection and operative treatment.

The objective of this study was to evaluate the incidence of avascular necrosis (AVN) of the femoral head in children less than 3 years of age with developmental dysplasia of the hip (DDH) treated with closed reduction, open reduction alone and open reduction combined with osteotomy. We reviewed clinical trials from the PubMed, EMBASE and Cochrane Library databases (up to November 2020) that were related to closed reduction, open reduction alone and open reduction combined with osteotomy for the treatment of children under 3 years of age with DDH. The screening and quality evaluation of the literature were performed independently by two researchers. In case of disagreement, a third researcher resolved the discourse. Finally, the data were extracted, and the R software and GeMTC program package were used to conduct a network meta-analysis (NMA). The evaluation index was the incidence of AVN. Fourteen articles were included. The NMA showed that in terms of the incidence of AVN, cases treated with open reduction alone were higher than those with closed reduction, and the difference was statistically significant. Open reduction alone had the highest probability (94.4%) of having the highest incidence of AVN, followed by open reduction combined with osteotomy (5.5%) and closed reduction (0.1%). In the treatment of children with DDH who are younger than 3 years old, open reduction alone is most likely to be the treatment with the highest incidence of AVN, followed by open reduction combined with osteotomy. The closed reduction had the smallest probability of AVN., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Infants referred for developmental dysplasia of the hip (DDH) may have a previously unidentified concomitant diagnosis of syndromic pathology. Our purpose was to examine the incidence of syndromic pathology in infants referred to a tertiary center with presumed idiopathic DDH and identify risk factors and difference in treatment courses between idiopathic and nonidiopathic cohorts., Methods: A retrospective analysis of a prospective cohort of infants younger than 3 years who were evaluated for DDH between 2008 and 2013 with a minimum 2-year follow-up. The clinical history and treatment were noted to determine the incidence and nature of concomitant syndromic diagnoses, after a confirmed diagnosis of DDH., Results: There were 202 patients: 177 were females (87.6%). Thirteen patients (6.4%) were later diagnosed with a neurologic/syndromic diagnosis. The workup leading to additional diagnosis was initiated by the orthopaedic surgeon in 8 of 13 patients (61.5%). Half of the referrals (4 of 8) made to other specialists were because of an abnormal treatment course (three-failure of typical DDH treatment and one-relapsed clubfeet). 7 of the 8 referrals were made because of developmental delays and decreased tone. 5 of the 13 nonidiopathic patients had other orthopaedic problems. The syndromic diagnoses included three cerebral palsy, two Kabuki syndrome, one Down syndrome, one myopathy, and one neuropathy. The diagnosis was made at an average of 2.3 years (0.04 to 4.7). No notable difference was observed in the incidence of the four known risk factors for DDH in syndromic patients compared with the idiopathic group. The syndromic patients required more open reductions (P = 0.002)., Discussion: By the age of 3 years, 6% of the patients treated for DDH were found to have a syndrome or neurologic abnormality, and the referral for workup was made by the treating surgeon greater than 60% of the time., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Orthopaedic Surgeons.)

Objectives: To provide an insight of the incidence of congenital developmental dysplasia of the hip in newborns from Yucatan born between 2015 and 2019 and analyze its association with maternal sociodemographic characteristics and neonatal, pregnancy and delivery related aspects., Methods: Retrospective, population-based study from Birth Registries database in Yucatan, Mexico between 2015 and 2019. Presence of hip dysplasia was described and analyzed considering three aspects (I) Maternal information (II) Pregnancy and birth (III) Neonatal examination. We obtained incidence rates from each year and the complete studied period. Association between hip dysplasia and maternal, neonatal and pregnancy/delivery variables was analyzed using logistic regression, unadjusted odds ratio and an adjusted model., Results: Hip dysplasia occurred in 13 per 10 000 live births. Significant associations were found between hip dysplasia and maternal place of residence in a city <50 000 inhabitants, without a local clinic. Propensity to give birth to a neonate with hip dysplasia increased with maternal age and ethnicity, in female newborns and when total number of pregnancy consultations summed <5. Newborns with hip dysplasia were heavier and less susceptible to be delivered vaginally. Congenital developmental hip dysplasia was comparatively more frequent among offspring of Mayan women and suboptimal access to medical care during pregnancy. Female neonates were affected the most, those first-borns. Neonates with hip dysplasia were heavier and more susceptible to be born by cesarean section., Conclusion: Maternal, neonatal, and perinatal factors are associated with DDH in Yucatecan infants born during 2015-2019. Factors that describe living conditions seems to have a more important effect on the presence of this condition., (© 2022 Wiley Periodicals LLC.)

Aims Developmental dysplasia of the hip (DDH) is an important cause of disability in children and young adults. Early diagnosis and treatment can help avoid more invasive interventions and long-term morbidity. This study examines the ultrasound screening programme conducted in University Hospital Waterford (UHW), and the outcomes for infants with DDH in the Southeast of Ireland. Methods We conducted an audit of all the DDH screening ultrasounds performed in UHW in the year 2020, a total of 992 infants. Data included referral and ultrasound times, screening results, interventions, and outcomes. Results Of those screened, 255 (26%) were referred to the Orthopaedic clinic, with a significant female majority of nearly 3:1. At the time of writing, only two infants were ultimately referred for further management of persistent DDH, the rest being successfully treated by less invasive interventions such as harnessing and bracing. There were no babies scanned within the recommended 6 weeks who later presented with a dislocated hip or required tertiary referral for DDH management. Conclusion The ultrasound screening programme in UHW is shown to be successful in the prompt diagnosis and early treatment of DDH. This plays a significant role in avoiding the lifelong disabling outcomes of untreated DDH, and the invasive surgical procedures required in the management of late-stage disease., Competing Interests: The authors have no conflicts of interest to declare.

Background: Congenital diastasis of the pubic symphysis (CDPS) is a rare musculoskeletal malformation in the exstrophy-epispadias complex that is potentially associated with the development of hip dysplasia. The purpose of this study was to investigate the incidence and prognostic factors of hip dysplasia in patients with CDPS., Methods: Fifty-four hips in 27 patients with CDPS initially evaluated between 1983 and 2016 were retrospectively reviewed. The mean age at the first visit was 2.3 (0 to 8) years. The mean follow-up duration was 10.5 (1 to 36) years. Patient characteristics at the first visit, the clinical course at the most recent follow-up, and radiologic parameters on pubic malformation and hip dysplasia during at least 2 time points (first visit or age 1, and either the most recent visit or before hip surgery) were evaluated. Prognostic factors associated with the development of hip dysplasia were analyzed using univariate/multivariate analysis. The Kaplan-Meier survival curves were generated and compared based on these factors., Results: Nine of 27 patients (33%) and 13 of 54 hip joints (24%) with CDPS developed hip dysplasia. Paraplegia (odds ratio, 10.0; 95% confidence interval, 1.7-76.6) and center-edge angle of <5 degrees at the first visit or age 1 (P<0.001) were independent predictors of the development of hip dysplasia. Patients with CDPS and either paraplegia or center-edge angle <5 degrees at the first visit or age 1 were significantly more likely to develop hip dysplasia than other patients (hazard ratio, 29.3; 95% confidence interval, 3.4-250)., Conclusions: Approximately one third of patients with CDPS develop hip dysplasia. Paraplegia and center-edge angle of <5 degrees at the first visit are independent risk factors., Level of Evidence: Level III., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose:  In Middle Europe developmental dysplasia of the hip (DDH) has an incidence of up to 5.9 %. The rate of congenital hip dislocation as the worst complication of a growth disorder of the hip is between 1.5 % and 2.5 %. Among known risk factors of DDH are breech position, multiples, foot deformities and family history. The aim of this retrospective study was to investigate prematurity as a risk factor for developmental dysplasia of the hip (DDH)., Materials and Methods:  The hips of 283 infants who were born before the 38 th week of gestation or earlier, and those of 377 infants who were born after the 37 th week of gestation, none of whom had other risk factors for DDH, were compared using the ultrasound technique according to Graf et al., within the first week after birth. Both hips of all infants were included in the study., Results:  Surprisingly, the difference in alpha angles between the two groups was statistically extremely significant, favoring the preterm infants. Moreover, we found a physiological curve of alpha angle development with a peak after the 31 st week of gestation. The incidence of pathological dysplasia was not significantly different in the two groups., Conclusion:  Our results suggest that prematurity is not a predisposing factor for DDH, but rather is protective for hip development., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: Breech presentation is one of the most important risk factors for developmental dysplasia of the hip, and all breech infants should be screened. The necessity of further follow-up of developmental dysplasia of the hip after normal clinical and sonographic screening is a controversial subject. The purpose of this study to identify the incidence of delayed dysplasia in breech infants after normal ultrasound screening and the necessity of further clinical and radiologic follow-up in these patients., Methods: We included the 292 breech babies (128 boys and 164 girls) who showed normal hip ultrasound screening results. To determine the incidence of delayed radiographic dysplasia, anteroposterior hip radiographs were taken between 12 and 24 months of age to measure the acetabular index (AI)., Results: The mean AI values were 22.8±3.4 in boys and 24.9±3.1 in girls. Applying the Tönnis criteria, 29 patients (9.9%) were considered to have delayed radiographic dysplasia (16 boys and 13 girls). No significant difference was found in any demographic variables between babies with and without delayed radiographic dysplasia. None of these 29 infants underwent any treatment for radiographic dysplasia. Applying Kuong's criteria to 292 infants, only 2 patients (0.7%) demonstrated radiographic dysplasia on the hip anteroposterior radiographs taken at 14 months., Conclusions: The incidence of radiographic dysplasia significantly varied depending on which criteria were applied. In order to find out more accurate incidence rates of delayed radiographic dysplasia, large-scale studies of the normative AI data for Korean infants are required., Level of Evidence: Prognostic Level III., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest form is provided with the online version of the article (http://links.lww.com/JBJS/G797).

Introduction: Identifying risk factors associated with developmental dysplasia of the hip (DDH) is essential for early diagnosis and treatment. Breech presentation is a major DDH risk factor, possibly because of crowding of the fetus within the uterus. In multifetal pregnancy, fetuses are generally smaller than singletons, which may obscure the effect of breech presentation on fetal hips. Only a few studies have investigated the occurrence of DDH in multifetal pregnancies. In this study, we aimed to evaluate whether the breech presentation is a major risk factor of DDH in twin pregnancies., Methods: This retrospective study included 491 consecutive live births (after 23+0 weeks gestation) delivered through cesarean section with at least 1 baby with noncephalic presentation in single or twin pregnancies from April 2013 to October 2018. We analyzed the incidence of DDH and its associated factors, including sex, breech, and multifetal pregnancy, with a generalized linear mixed model., Results: The incidence of DDH was 12.5% in singleton with breech presentation, 9.8% in twin-breech presentation, and 0.7% in twin-cephalic presentation. Multivariate analysis showed that singleton-breech presentation (P=0.003), twin-breech presentation (P=0.003), and female sex (P=0.008) were independent risk factors for DDH., Conclusion: Breech presentation is an independent risk factor for DDH in twin pregnancies, although twin pregnancy itself is not an independent risk factor for DDH., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Developmental dysplasia of the hip (DDH) is the most common musculoskeletal disorder of the infant age. Its incidence ranges from 0.06/1000 to 76.1/1000 live births and is more frequent in female infants. Breech position, family history and firstborn children are the main risk factors for DDH and this disorder is also associated with the presence of other congenital deformities. Anatomically, the acetabulum remains shallow and the femoral head grows in a wrong position. Clinical examination is important and tests such us Barlow and Ortolani give indications only for a part of the spectrum of this entity. Nowadays the sonographic examination is the most accurate option for the diagnosis. Graf classification categorizes the DDH cases in four types, from normal to dislocated hip, by description and measuring specific angles in sonographic examination. The wide usage of ultrasonography has decreased the non-diagnosed or neglected cases; treatment begins immediately in young age and is usually conservative with the usage of devices such as Pavlik harness and hip spica. To enhance the literature, we searched for published studies on DDH, to summarize the pathogenesis and the diagnosis and to discuss the treatment and outcome of the patients with this disorder.