Preterm birth does not increase the risk of developmental dysplasia of the Hip: a systematic review and meta-analysis.

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.

Known risk factors of the developmental dysplasia of the hip predicting more severe clinical presentation and failure of Pavlik harness treatment.

PURPOSE: Developmental dysplasia of the hip (DDH) varies from mild instability of the hip to subluxation or total dislocation of the joint. Well-known risk factors of DDH include pre-natal breech position, female sex, positive family history, hip side, primiparity and the mode of delivery. Aim of the present study was to further evaluate known risk-factors of DDH, find associations with more severe dysplasia (characterized with Ortolani positivity) and find risk factors of failure of the Pavlik harness treatment. MATERIAL AND METHODS: All children with the diagnosis of DDH treated in Tampere University hospital in the years 1998-2018 were retrospectively identified for the study and the data was collected from the medical records. Teratological dislocations (n = 3) were excluded from the analysis. Total of 945 patients were included. RESULTS: Breech presentation was strongly associated with Ortolani positivity (p < 0.001). Breech presentation was not associated with ending up for spica casting and/or operative treatment (p = 0.291) despite the association with Ortolani positivity. Ortolani positivity (p = 0.002), positive family history (p = 0.013) and girl sex (p = 0.029) were associated with ending up for spica casting and/or operative treatment. CONCLUSION: Breech presentation seems to increase the risk of Ortolani positive DDH. However, these infants are likely to recover with initially started Pavlik harness treatment, as it was not associated with elevated risk for undergoing more robust treatments. Positive family history and girl sex are associated with the most severe cases of developmental dysplasia of the hip, and it may predispose to the failure of the Pavlik harness treatment.

Radiographically successful periacetabular osteotomy does not achieve optimal contact mechanics in dysplastic hips.

BACKGROUND: Optimal correction of hip dysplasia via periacetabular osteotomy may reduce osteoarthritis development by reducing damaging contact stress. The objective of this study was to computationally determine if patient-specific acetabular corrections that optimize contact mechanics can improve upon contact mechanics resulting from clinically successful, surgically achieved corrections. METHODS: Preoperative and postoperative hip models were retrospectively created from CT scans of 20 dysplasia patients treated with periacetabular osteotomy. A digitally extracted acetabular fragment was computationally rotated in 2-degree increments around anteroposterior and oblique axes to simulate candidate acetabular reorientations. From discrete element analysis of each patient's set of candidate reorientation models, a mechanically optimal reorientation that minimized chronic contact stress exposure and a clinically optimal reorientation that balanced improving mechanics with surgically acceptable acetabular coverage angles was selected. Radiographic coverage, contact area, peak/mean contact stress, and peak/mean chronic exposure were compared between mechanically optimal, clinically optimal, and surgically achieved orientations. FINDINGS: Compared to actual surgical corrections, computationally derived mechanically/clinically optimal reorientations had a median[IQR] 13[4-16]/8[3-12] degrees and 16[6-26]/10[3-16] degrees more lateral and anterior coverage, respectively. Mechanically/clinically optimal reorientations had 212[143-353]/217[111-280] mm2 more contact area and 8.2[5.8-11.1]/6.4[4.5-9.3] MPa lower peak contact stresses than surgical corrections. Chronic metrics demonstrated similar findings (p ≤ 0.003 for all comparisons). INTERPRETATION: Computationally selected orientations achieved a greater mechanical improvement than surgically achieved corrections; however, many predicted corrections would be considered acetabular over-coverage. Identifying patient-specific corrections that balance optimizing mechanics with clinical constraints will be necessary to reduce the risk of osteoarthritis progression after periacetabular osteotomy.

Total hip arthroplasty associated with transverse subtrochanteric shortening osteotomy and conical stem fixation in Crowe type IV hip dysplasia.

PURPOSE: Total hip arthroplasty (THA) in high-dislocated hip dysplasia is a surgical challenge, presenting difficulties in the biomechanical reconstruction of the hip. The purpose of the present study is to analyze clinical and radiological outcomes of a series of patients with Crowe type IV hip dysplasia who underwent a THA with transverse subtrochanteric shortening osteotomy and conical stem fixation in our Hip surgery unit. METHODS: This non-interventional retrospective study included all patients diagnosed with Crowe type IV hip dysplasia who underwent a THA using a subtrochanteric shortening osteotomy and uncemented conical stem fixation between January 1, 2008, and December 31, 2015. Demographic, clinical and radiologic data were analyzed, including Harris Hip Score and Oxford Hip Score. RESULTS: Seventeen hips in 13 patients were included in the final analysis. All patients were women and mean age was 39 years (range 35-45). Mean follow-up was 5.6 years (range 1-8). Average length of the osteotomy was 3.4 cm (range 3-4.5) and mean lowering of the center of rotation was 5.67 cm (range 3.8-9.1). Mean time for bone union was 5.5 months. No nerve palsy or non-union was detected at the end of follow-up period. CONCLUSION: The use of cementless conical stem fixation associated with a transverse subtrochanteric shortening osteotomy for treating Crowe type IV hip dysplasia permits to correct the rotational alterations of the femur and provides good stability of the osteotomy, with very low risk of nerve palsy and non-union rates.

Epidemiology of Developmental Dysplasia of the Hip: Analysis of Japanese National Database.

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.

Clinical Outcomes of Total Hip Arthroplasty in Patients with Prior Periacetabular Osteotomy.

BACKGROUND: Periacetabular osteotomy (PAO) has been used as a treatment modality for development dysplasia of the hip (DDH). Many patients will progress to total hip arthroplasty (THA) following PAO. There is a discrepancy in the literature regarding outcomes of THA after PAO. METHODS: A retrospective study was performed. Ten pa- tients (12 hips) with prior PAO who progressed to THA with at least 1-year follow-up after THA were identified. A control group of patients matched for age, sex, and body mass index (BMI) who underwent primary THA with minimum of 1-year follow-up were included. Demographic and radiographic parameters as well as clinical outcomes using the modified Harris Hip Score (mHHS) were collected. RESULTS: The mean age at the time of THA was 36.2 ± 9.7 years for the PAO and 37.8 ± 9.1 years for the control cohorts. There was no difference in the demographics be- tween the groups. At mean follow-up time of 22.8 ± 10.7 months for the PAO group and 25 ± 13.8 months for the control group, there was no significant difference in mHHS following THA. There was significant improvement in mHHS from preoperative to postoperative levels (p < 0.01). CONCLUSION: Total hip arthroplasty is an effective means to restore quality of life and function in patients who develop osteoarthritis following PAO, with equivalent outcomes to those undergoing primary THA.

Ultrasound techniques for the detection of developmental dysplasia of the hip: a systematic review and meta-analysis.

BACKGROUND: Developmental dysplasia of the hip (DDH) encompasses a broad spectrum of hip pathologies, including femoral or acetabular dysplasia, hip instability, or both. According to the medical literature, ultrasonography is the most reliable diagnostic method for DDH. Several techniques for the assessment of hips in newborns and infants, using ultrasonography, have been described. OBJECTIVE: To compare the accuracy of the Graf technique and other diagnostic techniques for DDH. DESIGN AND SETTING: A systematic review of studies that analyzed ultrasound techniques for the diagnosis of DDH within an evidence-based health program of a federal university in São Paulo (SP), Brazil. METHODS: A systematic search of relevant literature was conducted in the PubMed, EMBASE, Cochrane Library, CINAHL, and LILACS databases for articles published up to May 5, 2020, relating to studies evaluating the diagnostic accuracy of different ultrasound techniques for diagnosing DDH. The QUADAS 2 tool was used for methodological quality evaluation. RESULTS: All hips were analyzed using the Graf method as a reference standard. The Morin technique had the highest rate of sensitivity, at 81.12-89.47%. The Suzuki and Stress tests showed 100% specificity. The Harcke technique showed a sensibility of 18.21% and specificity of 99.32%. CONCLUSION: All the techniques demonstrated at least one rate (sensibility and specificity) lower than 90.00% when compared to the Graf method. The Morin technique, as evaluated in this systematic review, is recommended after the Graf method because it has the highest sensitivity, especially with the three-pattern classification of 89.47%. REGISTRATION NUMBER: Identifier: CRD42020189686 at the International Prospective Register of Systematic Reviews (identifier: CRD42020189686).

Hip Morphology in Periacetabular Osteotomy (PAO) Patients Treated for Developmental Dysplasia of the Hip (DDH) as Infants Compared With Those Without Infant Treatment.

BACKGROUND: A subset of patients successfully treated for developmental dysplasia of the hip (DDH) as infants have symptomatic acetabular dysplasia at skeletal maturity leading to periacetabular osteotomy (PAO). The purpose of this study was to compare femoral and acetabular morphology in PAO patients with late acetabular dysplasia after previous treatment for DDH with PAO patients who do not have a history of DDH treatment. METHODS: A single surgeon's patients who underwent PAO between 2011 and 2021 were retrospectively reviewed. Patients previously treated for infantile DDH with a Pavlik harness, abduction brace, closed reduction and spica casting, or open reduction and spica casting were included. Patients with previous bony hip surgery were excluded. Preoperative radiographic measurements of each hip were recorded including lateral center edge angle, anterior center edge angle, and Femoro-Epiphyseal Acetabular Roof index. Computed tomography measurements included the coronal center edge angle, sagittal center edge angle, Tönnis angle, acetabular anteversion at 1, 2, and 3 o'clock, femoral neck-shaft angle, femoral version, and alpha angle. Control PAO cases without a history of DDH diagnosis or treatment were matched with the infantile DDH treatment group in a 2:1 ratio based on coronal center edge angle, age, and sex. RESULTS: There were 21 hips in 18 patients previously treated for infantile DDH (13 patients Pavlik harness, 3 abduction brace, 1 closed reduction, and 1 open reduction). The control PAO cohort was 42 hips in 42 patients who did not have previous DDH treatment. There was no statistically significant difference in any of the recorded measurements between patients previously treated for DDH and those without previous treatment including femoral version (P=0.494), anteversion at 1 o'clock (P=0.820), anteversion at 2 o'clock (P=0.584), anteversion at 3 o'clock (P=0.137), neck-shaft angle (P=0.612), lateral center edge angle (P=0.433), Femoro-Epiphyseal Acetabular Roof index (P=0.144), and alpha angle (P=0.156). CONCLUSIONS: Femoral and acetabular morphology is similar between PAO patients with persistent symptomatic acetabular dysplasia following DDH treatment and patients presenting after skeletal maturity with acetabular dysplasia and no previous history of DDH treatment. LEVEL OF EVIDENCE: Level III-case-control, prognostic study.

Risk Factors for Composite Failure of Hip Dysplasia Treated With Periacetabular Osteotomy: A Minimum 10-Year Follow-up.

INTRODUCTION: Periacetabular osteotomy (PAO) is a common surgical treatment of prearthritic hip dysplasia in young adults, but there are few long-term studies of clinical outcomes. The purpose of this investigation was to report a minimum 10-year clinical follow-up of hip dysplasia treated with PAO and identify risk factors for composite failure. METHODS: We identified 151 patients (198 hips) who underwent PAO to treat hip dysplasia at a single institution. Enrolled subjects completed a series of six patient-reported outcome instruments and provided information about subsequent surgeries. We defined composite failure as conversion to total hip arthroplasty or modified Harris Hip Score ≤70. Logistic regression with generalized estimating equations was used to evaluate the relationships between odds of failure and potential predictor variables in univariate and multivariate analyses. RESULTS: A total of 124 subjects (167 hips) with a minimum 10-year follow-up were enrolled. The median time from PAO to the final follow-up was 13 years (range 10-18 years). There were 71 hips that met criteria for failure: 32 with total hip arthroplasty and 39 with modified Harris Hip Score ≤70. Univariate logistic regression analyses revealed multiple preoperative factors that predicted composite failure: increased age and body mass index, osteoarthritis (OA), and more severe acetabular dysplasia. Postoperative factors that predicted failure included lateral undercoverage and formation of heterotopic ossification (HO). The final multivariate model identified body mass index ≥30 kg/m2 (odds ratio [OR], 3.84 [95% confidence interval (CI), 1.68-8.78], P = 0.001), higher preoperative Tönnis grade OA (OR, 2.65 [95% CI, 1.50-4.66], P < 0.001), and HO formation (OR, 16.52 [95% CI, 2.08-135.96], P = 0.009) as independent predictors of failure. CONCLUSIONS: This study corroborates current hip dysplasia literature, identifying increasing age and presence of preoperative OA as risk factors for composite failure in univariate analyses. In addition, we found that obesity and HO formation were independent predictors of persistent hip dysfunction. LEVEL OF EVIDENCE: Therapeutic Level IV.

Breech Presentation in Twins as a Risk Factor for Developmental Dysplasia of the Hip.

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.

Restauración de la biomecánica en artroplastia total de cadera por luxación congénita alta / Restoration of Biomechanics in Total Hip Arthroplasty Due to High Congenital Dislocation

La osteoartritis secundaria a displasia o luxación congénita de cadera conlleva grandes dificultades para el cirujano que reconstruye la cadera. Los casos con escasa deformidad no difieren prácticamente de la reconstrucción primaria convencional. En el extremo opuesto están los casos con graves hipoplasias del acetábulo, escaso desarrollo femoral, luxación completa, discrepancia importante de las extremidades y gran cabalgamiento del trocánter mayor. Por las enormes dificultades que pueden representar para la cirugía, nos trazamos el objetivo de discutir nuestro caso, con las consideraciones y resultados del tratamiento elegido. Se presenta paciente femenina de 54 años de edad, con antecedentes de salud previa, que nos llegó a consulta con una grave deformidad congénita, acortamiento del miembro inferior derecho (6 cm) y limitación dolorosa de todos los movimientos de la cadera. Se constata una luxación congénita grado C de Hartofilakidis y IV de Crowe, que muestra como parte del tratamiento, la artroplastia total con injerto autólogo y reimplantación del cótilo en el acetábulo verdadero, para recuperar el centro de rotación del acetábulo y la osteotomía femoral de acortamiento para la implantación del vástago femoral. Se exponen los requerimientos, procederes técnicos y resultados alcanzados(AU)

Osteoarthritis secondary to congenital hip dysplasia or dislocation poses great difficulties for the surgeon reconstructing the hip. Cases with little deformity do not differ practically from conventional primary reconstruction. At the opposite end there are cases with severe acetabulum hypoplasia, poor femoral development, complete dislocation, significant limb discrepancy, and great thrust of the greater trochanter. Due to the enormous difficulties that they can represent for surgery, we set the objective of discussing our case, with the considerations and results of the chosen treatment. A 54-year-old female patient is reported, she has previous health history, and she came for consultation with severe congenital deformity, shortening of her right lower limb (6 cm) and painful limitation of all hip movements. Congenital dislocation grade C of Hartofilakidis and IV of Crowe was confirmed, which showed as part of the treatment, the total arthroplasty with autologous graft and reimplantation of the cup in the true acetabulum, to recover the center of rotation of the acetabulum and the shortening femoral osteotomy for implantation of the femoral stem. Requirements, technical procedures and results achieved are informed(AU)

Traditional Mongolian swaddling and developmental dysplasia of the hip: a randomized controlled trial.

BACKGROUND: Mongolian traditional swaddling of infants, where arms and legs are extended with a tight wrapping and hips are in adduction position, may lead to abnormal maturation and formation of the hip joint; and is a contributing factor for developmental dysplasia of the hip (DDH). This hypothesis was tested in this randomized controlled trial. METHODS: Eighty newborns with one or two hips at risk of worsening to DDH (Graf Type 2a; physiologically immature hips) at birth were randomized into 2 groups at a tertiary hospital in Ulaanbaatar. The "swaddling" group (n = 40) was swaddled in the common traditional Mongolian method for a month while the "non-swaddling" group (n = 40) was instructed not to swaddle at all. All enrollees were followed up on monthly basis by hip ultrasound and treated with an abduction-flexion splint if necessary. The groups were compared on the rate of Graf's "non-Type 1" hips at follow-up controls as the primary outcome. Secondary outcomes were rate of DDH and time to discharge (Graf Type 1; healthy hips). In addition, correlation between the primary outcome and swaddling length in days and frequency of swaddling in hours per day were calculated. RESULTS: Recruitment continued from September 2019 to March 2020 and follow-up data were completed in June 2020. We collected final outcome data in all 80 enrollees. Percentages of cases with non-Type 1 hip at any follow-up examination were 7.5% (3/40) in the non-swaddling group and 40% (16/40) in the swaddling group (p = 0.001). There was no DDH case in the non-swaddling group while there were 8 cases of DDH in the swaddling group. The mean time to discharge was 5.1 ± 0.3 weeks in the non-swaddling group and 8.4 ± 0.89 weeks in the swaddling group (p = 0.001). There is a correlation between the primary outcome and the swaddling frequency in hours per day (r = 0.81) and swaddling length in days (r = 0.43). CONCLUSIONS: Mongolian traditional swaddling where legs are extended and hips are in extension and adduction position increases the risk for DDH. TRIAL REGISTRATION: Retrospectively registered, ISRCTN11228572 .

Recomendaciones en la pesquisa y diagnóstico de la displasia del desarrollo de las caderas / Screening and diagnostic recommendations in the developmental dysplasia of the hip

La displasia del desarrollo de la cadera (DDC) es una anomalía de la articulación coxofemoral caracterizada por una laxitud o posicionamiento anormal de la cabeza femoral con respecto al acetábulo. Es la patología ósea perinatal más frecuente, e incluye alteraciones que van desde el aplanamiento o la displasia acetabular hasta una luxación completa de la cabeza femoral fuera de la articulación, que puede comprometer el desarrollo y la estabilidad articular. Nuestro objetivo es transmitir una sistemática de estudio en la valoración de la cadera del recién nacido, haciendo énfasis en un examen físico correcto como pilar fundamental en la detección de la DDC, y orientar al pediatra en la selección adecuada del método diagnóstico complementario acorde a edad del paciente, con el fin de optimizar la detección y reducir el número de caderas luxadas en etapas tempranas y tardías, y así disminuir la incidencia de patologías asociadas desarrolladas a partir de este trastorno

Developmental dysplasia of the hip (DDH) is a hip joint anomaly that is characterized by a laxity or abnormal positioning of the femoral head with respect to the acetabulum. It is the most common perinatal pathology of the skeleton and includes a spectrum of alterations ranging from flattening or acetabular dysplasia, to a complete dislocation of the femoral head outside the joint that can compromise joint development and stability. The purpose of this presentation is to transmit a systematic study in the evaluation of the newborn's hip, emphasizing a correct physical examination as primordial in the detection of DDH. Also, guide the pediatriciain the proper selection of the complementary diagnostic method to be used according to the age of the patient, in order to optimize detection and reduce the number of dislocated hips in early and late stages as well as the incidence of related pathologies.

Current Evidence about Developmental Dysplasia of the Hip in Pregnancy.

In adults, developmental dysplasia of the hip (DDH) represents a spectrum of disorders. It is commonly found in women in routine orthopedic practice. Hip dysplasia is a leading precursor of joint laxity; when untreated, it can contribute to chronic modifications, such as thickening of the pulvinar and ligamentum teres (which can also elongate), hypertrophy of the transverse acetabular ligament, and osteoarthritis. DDH is presumed to be associated with alterations in pelvic morphology that may affect vaginal birth by the reduction in the transverse diameter of the pelvic inlet or outlet. Here, we provide an overview of the current knowledge of pregnancy-associated DDH. We primarily focused on how a surgical DDH treatment might influence the pelvic shape and size and the effects on the mechanism of birth. We presented the female pelvis from the standpoint of bone and ligament morphology relative to a pelvic osteotomy. Then, we described whether the pregnancy was impacted by previous surgical DDH treatments, performed from infancy to adulthood. In conclusion, hip dysplasia is not associated with high-risk complications during pregnancy or with increased difficulty in vaginal delivery.

Can developmental dysplasia of the hip be identified in the prenatal period? A pilot study: Ultrasonographic evaluation and postnatal follow-up results of fetal hips in the third trimester.

OBJECTIVE: This study aimed to determine the predictability of developmental dysplasia of the hip (DDH) in the prenatal period by means of evaluating fetal hips using the Graf method on obstetric ultrasonography (US) after the 34th week of gestation. METHODS: A total of 84 pregnant women (mean age = 27.04; age range = 19-46 years), who were referred to our radiology clinic for an obstetric US examination in the third trimester, and their fetuses were included in this study. In the obstetric US, alpha angles of both hips of the fetuses were measured based on Graf's method, and each case was assessed ultrasonographically by a second physician at 6-10 postnatal weeks. Prenatal and postnatal hips were then classified according to alpha angles as ≥ 60° or < 60°. The kappa coefficients between the diagnoses based on prenatal and postnatal alpha angles were calculated. RESULTS: According to the postnatal alpha angle, 77 fetuses were diagnosed to have type 1 right hip and 7 fetuses had type 2A right hip. The prenatal alpha angle provided the same results (77 type 1 and 7 type 2A right hips). Similarly, the postnatal alpha angle revealed type 1 left hip in 82 fetuses and type 2A left hip in 2 fetuses, which was the same as the diagnoses based on the prenatal alpha angles. There was a complete agreement between prenatal and postnatal alpha measurements for both the left and right hips (kappa = 1.00, P < 0.001). CONCLUSION: Evidence from this study has revealed that DDH can be identified by obstetric ultrasonographic examinations in the prenatal period.

Developmental Dysplasia of the Hip: A Review of Etiopathogenesis, Risk Factors, and Genetic Aspects.

As one of the most frequent skeletal anomalies, developmental dysplasia of the hip (DDH) is characterized by a considerable range of pathology, from minor laxity of ligaments in the hip joint to complete luxation. Multifactorial etiology, of which the candidate genes have been studied the most, poses a challenge in understanding this disorder. Candidate gene association studies (CGASs) along with genome-wide association studies (GWASs) and genome-wide linkage analyses (GWLAs) have found numerous genes and loci with susceptible DDH association. Studies put major importance on candidate genes associated with the formation of connective tissue (COL1A1), osteogenesis (PAPPA2, GDF5), chondrogenesis (UQCC1, ASPN) and cell growth, proliferation and differentiation (TGFB1). Recent studies show that epigenetic factors, such as DNA methylation affect gene expression and therefore could play an important role in DDH pathogenesis. This paper reviews all existing risk factors affecting DDH incidence, along with candidate genes associated with genetic or epigenetic etiology of DDH in various studies.

Genetic Predisposition to Developmental Dysplasia of the Hip.

BACKGROUND: The etiopathogenesis of developmental dysplasia of the hip (DDH) has not been clarified. This systematic review evaluated current literature concerning all known chromosomes, loci, genes, and their polymorphisms that have been associated or not with the prevalence and severity of DDH. METHODS: Following the established methodology of Meta-analysis of Observational Studies in Epidemiology guidelines, MEDLINE, EMBASE, and Cochrane Register of Controlled Trials were systematically searched from inception to January 2019. RESULTS: Forty-five studies were finally included. The majority of genetic studies were candidate gene association studies assessing Chinese populations with moderate methodological quality. Among the most frequently studied are the first, third, 12th,17th, and 20th chromosomes. No gene was firmly associated with DDH phenotype. Studies from different populations often report conflicting results on the same single-nucleotide polymorphism (SNP). The SNP rs143384 of GDF5 gene on chromosome 20 demonstrated the most robust relationship with DDH phenotype in association studies. The highest odds of coinheritance in linkage studies have been reported for regions of chromosome 3 and 13. Five SNPs have been associated with the severity of DDH. Animal model studies validating previous human findings provided suggestive evidence of an inducing role of mutations of the GDF5, CX3CR1, and TENM3 genes in DDH etiopathogenesis. CONCLUSION: DDH is a complex disorder with environmental and genetic causes. However, no firm correlation between genotype and DDH phenotype currently exists. Systematic genome evaluation in studies with larger sample size, better methodological quality, and assessment of DDH patients is necessary to clarify the DDH heredity. The role of next-generation sequencing techniques is promising.

Exploración ecográfica de las caderas del bebé en mochilas de porteo / Evaluation by ultrasound of the hips of babies carried in baby carriers

Antecedentes y objetivo: La displasia de cadera se ha asociado con factores de riesgo como la presentación de nalgas, el sexo femenino o los antecedentes familiares. Sin embargo, factores externos, como los sistemas de porteo, parecen influir en el desarrollo de la cadera en los primeros meses de vida. El objetivo del presente trabajo es valorar por imagen ecográfica la posición de las caderas en bebés colocados en diferentes tipos de mochilas portabebés. Método: Se ha realizado un estudio ecográfico de las caderas de bebés sanos entre 1,5 y 3,5meses de edad, cuando el niño es porteado en tres diferentes mochilas portabebés que proporcionan diferentes grados de sujeción de los muslos del bebé. Todas las caderas eran tipoI de Graf. Se han valorado tres parámetros ecográficos: el ángulo alfa de Graf, la cobertura acetabular y la distancia a pubis en situación basal (mesa de exploración) y en las tres diferentes mochilas de porteo. Resultados: En todos los casos los bebés mostraron valores de normalidad en los tres parámetros estudiados, sin diferencias estadísticamente significativas entre ninguna de las situaciones. Tampoco se encontraron diferencias en los parámetros ecográficos relacionadas con el sexo, la edad o el peso del bebé. Conclusiones: La cadera derecha del bebé mantiene unos parámetros ecográficos de normalidad cuando es colocada en cualquiera de los modelos de mochila estudiados

Background and objective: Hip dysplasia has been associated with risk factors such as breech presentation, female gender or family history. However, external factors, such as the use of baby carriers, seem to influence the development of the hip in the first months of life. The aim of this study is to evaluate the position of the hips of babies placed in different types of baby carriers by ultrasound image. Method: An ultrasound study of the hips of healthy babies between 1.5 and 3.5 months of age was carried out, when the children were carried in three different baby backpacks, which provide different degrees of support for the babies' thighs. All hips were typeI according to the Graf classification. Graf's alpha angle, acetabular coverage and distance to the pubis were assessed at baseline (examination table) and when the children were carried in the three different backpacks. Results: In all cases, the babies showed normal values in the three studied parameters, without statistically significant differences between any of the situations. There were also no differences in the ultrasound parameters related to the sex, age or weight of the baby. Conclusions: The right hip of the babies shows normal ultrasound parameters when placed in any of the baby carriers studied

Evaluation by ultrasound of the hips of babies carried in baby carriers. / Exploración ecográfica de las caderas del bebé en mochilas de porteo.

BACKGROUND AND OBJECTIVE: Hip dysplasia has been associated with risk factors such as breech presentation, female gender or family history. However, external factors, such as the use of baby carriers, seem to influence the development of the hip in the first months of life. The aim of this study is to evaluate the position of the hips of babies placed in different types of baby carriers by ultrasound image. METHOD: An ultrasound study of the hips of healthy babies between 1.5 and 3.5 months of age was carried out, when the children were carried in three different baby backpacks, which provide different degrees of support for the babies' thighs. All hips were typeI according to the Graf classification. Graf's alpha angle, acetabular coverage and distance to the pubis were assessed at baseline (examination table) and when the children were carried in the three different backpacks. RESULTS: In all cases, the babies showed normal values in the three studied parameters, without statistically significant differences between any of the situations. There were also no differences in the ultrasound parameters related to the sex, age or weight of the baby. CONCLUSIONS: The right hip of the babies shows normal ultrasound parameters when placed in any of the baby carriers studied.