Developmental dysplasia of the hip: a new approach to incidence

Surgery simulation teaching based on real reconstruction aid versus traditional surgical live teaching in the acquisition of an adult total hip arthroplasty surgical technique for developmental dysplasia of the hip: a randomized comparative study

BACKGROUND

A simulation and model (SM) teaching aid using 3D printing was developed to improve a training course for total hip arthroplasty of adult developmental dysplasia of the hip (adult DDH-THA). We named this new method Surgery Simulation Teaching based on a Real Reconstruction Aid (RRA-SST). A prospective randomized comparison was performed with the traditional surgical live teaching method to evaluate the training effectiveness of RRA-SST for adult DDH-THA.

METHODS

Twenty-six trainees, who were already practicing but were not experienced, participated in the study. We randomly divided the trainees into two groups: Group A (n = 13) received RRA-SST and group B (n = 13) received traditional surgical live teaching. A surgery simulation test and a questionnaire were used for evaluation. Next, each group received training with the other teaching method, and then the test and questionnaire were used again for evaluation.

RESULTS

After the first test, the RRA-SST method was shown to produce better results than the traditional surgical live teaching method. After the second test, the results showed the training effect in both groups reached the same level, which was level as Group A RRA-SST results. Analysis of the questionnaire results showed that the training effect of RRA-SST was higher than that of traditional surgical live teaching, from multiple perspectives.

CONCLUSIONS

The use of RRA-SST improved participant performance according to simulation assessment. RRA-SST can be helpful for trainees who are already practicing but not experienced when developing proficiency in adult DDH-THA surgical techniques.

Developmental dysplasia of the hip

Developmental dysplasia of the hip encompasses a range of hip abnormalities in which the femoral head and acetabulum fail to develop and articulate anatomically. Developmental dysplasia of the hip is a clinically important condition, with a prevalence of 1-2/1000 in unscreened populations and 5-30/1000 in clinically screened populations. The pathology is incongruence between the femoral head and the acetabulum, which can be caused by an abnormally shaped femoral head, acetabulum, or both. This results in a spectrum of different hip abnormalities. The precise aetiology behind developmental dysplasia of the hip is unclear, but there are a number of established risk factors. In the UK, universal clinical examination of newborns and 6-8-week-old babies is performed under the national UK newborn screening programme for developmental dysplasia of the hip (part of the Newborn and Infant Physical Examination). The physical examination of the newborn hip involves initial inspection of the infant for any of the clinical features of developmental dysplasia of the hip, followed by hip stability tests (Barlow's and Ortolani's tests). Hip ultrasound is the gold standard diagnostic and monitoring tool for developmental dysplasia of the hip in newborns and infants under 6 months of age, or until ossification of the femoral head. Some mild cases of developmental dysplasia of the hip (and the immature hip) resolve without requiring intervention; however, there are a number of treatments, both non-operative and operative, that may be used at various stages of this condition.

Biomechanical evaluation of femoral anteversion in developmental dysplasia of the hip and potential implications for closed reduction

BACKGROUND

Earlier clinical reports have identified femoral anteversion as a factor associated with developmental dysplasia of the hip. This study investigates the biomechanical influence of femoral anteversion on severe dislocations and its effect on hip reduction using the Pavlik harness.

METHODS

A computational model of an infant lower-extremity, representing a ten-week old female was used to analyze the biomechanics of anteversion angles ranging from 30° to 70° when severe dislocation was being treated with the Pavlik harness. Specifically, the effects and relationships between muscle passive response and femoral anteversion angle were investigated over a range of hip abduction and external rotation.

FINDINGS

Results of this study suggest that increased femoral anteversion may decrease the success rate for treatment of high-grade developmental dysplasia of the hip when using the Pavlik harness. However, hip external rotation and decreased abduction in the harness may facilitate initial reduction in these cases.

INTERPRETATION

This biomechanical study may help explain why dissections of newborn specimen with developmental dysplasia of the hip have shown normal distribution of femoral anteversion in contrast to studies of patients requiring surgery where greater frequency of increased femoral anteversion has been reported. This study also suggests that adjusting the Pavlik harness to increase external hip rotation and decrease hip abduction may facilitate initial reduction for severe dislocations with increased femoral anteversion.

Bone cement spacer: a novel technique for treating a complicated case of developmental dysplasia of the hip with an injured acetabulum: Case report with 7-year follow-up

RATIONALE

Developmental dysplasia of the hip (DDH) has an incidence of 5 per 1000 newborns and its management depends on various factors. We present a rare case of DDH with soft tissue obliteration and a bony prominence in the center of the acetabulum after failed open reduction and acetabuloplasty.

PATIENT CONCERNS

A 20-month-old girl presented to our clinic with right hip stiffness after undergoing open reduction and acetabuloplasty at another hospital.

DIAGNOSES

The diagnosis of DDH was made using a computed tomography scan that revealed a right hip dislocation with soft tissue obliteration and a bony prominence in the center of the acetabulum.

INTERVENTIONS

We used a novel technique for treating the rare presentation of complicated DDH with massive soft tissue obliteration and bony prominence in the center of the acetabulum after failed open reduction and acetabuloplasty. The right hip was surgically explored. The acetabulum was deepened and resurfaced. Bone cement was applied over the acetabulum to prevent future ankylosis.

OUTCOMES

At the follow-up 7 years after the last surgery, the patient had regained full range of motion and a properly reduced right hip with optimal acetabular coverage on radiographs.

LESSONS

Care must be taken in any patient with DDH who presents with hip redislocation after open reduction. If deepening and resurfacing of the acetabulum are required, bone cement could be used as a temporary spacer for 8 weeks; this was key in treating our patient.

Computational model of a synovial joint morphogenesis

Joints enable the relative movement between the connected bones. The shape of the joint is important for the joint movements since they facilitate and smooth the relative displacement of the joint's parts. The process of how the joints obtain their final shape is yet not well understood. Former models have been developed in order to understand the joint morphogenesis leaning only on the mechanical environment; however, the obtained final anatomical shape does not match entirely with a realistic geometry. In this study, a computational model was developed with the aim of explaining how the morphogenesis of joints and shaping of ossification structures are achieved. For this model, both the mechanical and biochemical environments were considered. It was assumed that cartilage growth was controlled by cyclic hydrostatic stress and inhibited by octahedral shear stress. In addition, molecules such as PTHrP and Wnt promote chondrocyte proliferation and therefore cartilage growth. Moreover, the appearance of the primary and secondary ossification centers was also modeled, for which the osteogenic index and PTHrP-Ihh concentrations were taken into account. The obtained results from this model show a coherent final shape of an interphalangeal joint, which suggest that the mechanical and biochemical environments are crucial for the joint morphogenesis process.

Should paediatricians initiate orthopaedic hip dysplasia referrals for infants with isolated asymmetric skin folds?

PURPOSE

Asymmetric skin folds (ASFs) have been linked to developmental dysplasia of the hip (DDH) in select studies, leading to their inclusion in paediatric practice guidelines regarding orthopaedic referral for hip evaluation. The purpose of this study was to investigate the utility of isolated ASFs as a screening tool for DDH in a series of patient referrals evaluated at a single institution.

METHODS

We performed a retrospective review of consecutive patients between 0 and 12 months of age referred to orthopaedic clinics for isolated ASFs. We recorded radiographic findings (acetabular inclination or alpha angle), diagnosis rendered and treatment administered.

RESULTS

A total of 66 patients were included (mean age 6.4 months; 2.47 to 10.76). All patients received pelvic radiographs or ultrasound. In all, 36 patients (55%) were considered normal by their treating physician and 25 (38%) were considered dysplastic and underwent brace treatment. One hip with an isolated ASF was found to have a dislocated hip on radiograph prior to their initial orthopaedic visit. None of the patients in this study have required surgery to date.

CONCLUSION

Using ASFs as a reason for referral led to increased diagnosis of mild dysplasia resulting in orthotic treatment. Thus, in our particular clinical environment, isolated ASFs can be an indicator of mild dysplasia and warrant further workup or referral. Because treatment philosophies regarding recognition and treatment of mild dysplasia vary amongst centres, the value of screening with ASFs likewise depends on the treating orthopaedic surgeon's threshold for treatment of mild dysplasia.

LEVEL OF EVIDENCE

Level IV- Retrospective.

Ultrasound Characteristics of Clinically Dislocated But Reducible Hips With DDH

BACKGROUND

Although ultrasound (US) is frequently used in diagnosis and management of infantile developmental dysplasia of the hip, precise ultrasonographic parameters of what constitutes a dislocation, subluxation etc remain poorly defined. The purpose of this study was (1) to describe the ultrasonographic characteristics of a large cohort of clinically dislocated but reducible hips and (2) to begin to develop ultrasonographic definitions for what constitutes a hip dislocation.

METHODS

A retrospective review of prospectively collected data from an international multicenter study group on developmental dysplasia of the hip was conducted on all patients under 6 months of age with hip(s) that were dislocated at rest but reducible based on initial physical examination (ie, Ortolani positive). Femoral head coverage (FHC), alpha angle (α), and beta angle (β) were measured on pretreatment US by the individual treating surgeon, and were recorded directly into the database.

RESULTS

Based on 325 Ortolani positive hips, the median FHC on presentation was 10% with an interquartile range of 0% to 23%. A total of 126 of the 327 hips (39%) demonstrated 0% FHC. The 90th percentile was found to be at 33% FHC. Of 264 hips with sufficient α data, the median α was 43 degrees with an interquartile range from 37 to 49 degrees. The 90th percentile for α was at 54 degrees. A total of 164 hips had documented β with a median of 66 degrees and an interquartile range of 57 to 79 degrees; the 90th percentile was at 94 degrees.

CONCLUSIONS

Analysis of a large cohort of patients with dislocated but reducible hips reveals a median percent FHC of 10%, a median α of 43 degrees, and a median β of 66 degrees on initial US. Using a threshold at the 90th percentile, a sensible ultrasonographic definition of a dislocated hip seems to be FHC≤33%, implying that FHC between 34% and 50% may be reasonably termed a subluxation. Although these findings are consistent with previous, smaller reports, further prospective research is necessary to validate these thresholds.

LEVEL OF EVIDENCE

Level IV-diagnostic study.

Secondary hip dysplasia increases risk for early coxarthritis after Legg-Calve-Perthes disease. A study of 255 hips

The biomechanical parameters of the hip joint articular surface were analysed in 141 adult hips after Legg-Calve Perthes Disease, and 114 contralateral unaffected hips (controls), by using HIPSTRESS mathematical models. Geometrical parameters, assessed from anteroposterior and axial radiograms, were used as input to models for resultant hip force and contact hip stress. Results confirm previous indications that head enlargement after the Legg-Calve-Perthes Disease compensates the values of hip stress. Furthermore, it was found that an increased risk for coxarthritis development after the disease is secondary to concomitant hip dysplasia, with considerable and statistically significantly lower centre-edge angle and unfavourable distribution of stress.

Screening program for neonates at risk for developmental dysplasia of the hip: comparing first radiographic evaluation at five months with the standard twelve week ultrasound. A prospective cross-sectional cohort study

Purpose

To assess whether delayed radiological hip screening at five months (versus ultrasound at 3 months) results in a higher incidence of persistent developmental dysplasia of the hip (DDH) at 18 months.

Methods

We analyzed 3536 screened neonates (2009–2013) at age two to three weeks. In the case of risk factors for DDH, 460 infants were assigned to a pelvic radiograph at five months between 2009 and 2010 and 651 infants were assigned to an ultrasound at three months (2011–2013). In the case of DDH, appropriate treatment was started and radiological follow-up occurred at eight, ten, 12, and 18 months. We compared incidence and severity of persistent DDH at 18 months. Analysis was performed using linear regression.

Results

Both groups were comparable for risk factors (breech, gender, twins, family history). Eighty-nine patients (2.5%) showed DDH (n = 43 (group 1), n = 46 (group 2)). At 18 months, ten patients showed persistent DDH (n = 8 (group 1), n = 2 (group 2) (7.7% vs. 0.3% respectively)). The mean acetabular index (AI) at 18 months in group 1 (left hip) is 22.4° (95% CI 20.6–24.3°) vs. group 2 at 22.3° (95% CI 21.2–23.4°) (p = 0.098). The mean AI in group 1 (right hip) is 21.9° (95% CI 18.9–24.9°) vs. 21.2° (95% CI 20.5–22.0°) in group 2 (p = 0.293). Adjusted for risk factors, there is no difference in incidence of persistent DDH between both groups after 18 months (OR 0.519; 0.07, 3.845).

Discussion

This study revealed no significant difference in incidence or severity of persistent DDH at 18 months between the two screening groups. These results suggest justification for delayed screening to prevent overtreatment of immature hips.

Conclusion

In clinically stable hips, delayed ultrasound between three and five months is regarded as safe and could prevent for overtreatment of mild dysplastic hips.

Socioeconomic Risk Factors for Poor Outcomes of Developmental Dysplasia of the Hip

OBJECTIVE

To examine the relationship between socioeconomic factors and outcomes of developmental dysplasia of the hip (DDH).

STUDY DESIGN

A retrospective review of patients with DDH at a tertiary pediatric hospital from 2003 to 2012 with 2 years minimum follow-up was conducted. The relationship between socioeconomic factors with late presentation, treatment, and outcomes was examined. Socioeconomic factors included insurance status, language, and ethnicity.

RESULTS

In total, 188 patients met criteria. Patients with late presentations were more likely to be Hispanic (P = .02). However, public insurance and a non-English language were not associated with late presentation. Hispanic patients (P = .01) and patients with a non-English language (P = .01) had a lower nonoperative treatment success rate. Hispanic patients had more surgical procedures performed than non-Hispanic patients (P = .04). Patients with range of motion limitations were more likely to have public insurance (P = .05) and be Hispanic (P = .04). On multiple logistic regression analysis controlling for late presentation, patients with public insurance had increased odds of range of motion limitations (OR 2.22, P = .04). Patients with public insurance (OR 0.44, P = .04), a non-English primary language (OR 0.30, P < .01), and Hispanic ethnicity (OR 0.37, P = .01) had decreased odds of successful nonoperative treatment.

CONCLUSIONS

Public insurance, a non-English language, and Hispanic ethnicity are risk factors for inferior outcomes for DDH. When controlling for late presentation, these were significant risk factors for nonoperative treatment failure.

Ultrasound screening for developmental dysplasia of the hip after 4 weeks increases exam accuracy and decreases follow-up visits

BACKGROUND

Developmental dysplasia of the hip (DDH) is a preventable and treatable disorder in children. Hip ultrasound is recommended for early detection of affected hips. The timing of the initial hip ultrasound and the frequency of subsequent ultrasounds are controversial topics when considering costs and efficiency.

METHODS

Registry data from the Taiwanese Screening and Audit System for Developmental Dysplasia of the Hip were obtained for biometry of hip ultrasounds using the Graf classification and relevant demographic data from 2016. Initial screening results and final case management outcomes were compared to determine screening accuracy and the number of visits needed to determine final outcomes.

RESULTS

In total, we screened 1683 newborns in 2016. Of the initial cases screened within 28 days (n = 1168), 86.6% were negative, 10.1% positive, and 3.3% intermediate, while of the cases screened after 28 days (n = 515), 97.3% were negative, 0.8% positive, and 1.9% intermediate. Screening of the newborns' final hip outcomes revealed that 1641 (97.6%) were negative, treatment was administered in 8 cases (0.4%), and 34 (2.0%) cases were lost to follow-up. When comparing screening times, screening after 28 days improved specificity (89%-97%), and later screenings were associated with fewer visits needed to confirm hip outcomes (aOR = 0.19, CI95% = 0.10-0.38, p < 0.001) and improved accuracy (aOR = 13.84, CI95% = 4.23-45.26, p < 0.001).

CONCLUSION

This study provides evidence of the benefits of screening for DDH after 28 days, namely: reduced false positives, improved screening accuracy, and a reduced requirement for follow-up visits. Delaying screening can also potentially reduce unnecessary parental anxiety, eliminate unnecessary healthcare burdens, and reduce costs. We recommend performing hip ultrasound screening for newborns after 28 days.

Developmental dysplasia of the hip: addressing evidence gaps with a multicentre prospective international study

There is a lack of high quality evidence available to guide clinical practice in the treatment and management of developmental dysplasia of the hip (DDH). Evidence has been limited by persistent confusion on diagnostic and classification terminology, variability in surgeon decision making and a reliance on single centre, retrospective studies with small patient numbers. To address gaps in knowledge regarding screening, diagnosis and management of DDH, the International Hip Dysplasia Institute began a multicentre, international prospective study on infants with hips dislocated at rest. This review discusses the current state of screening, diagnostic and management practices in DDH and addresses important unanswered questions that will be critical in identifying best practices and optimising patient outcomes. There is insufficient evidence to support universal ultrasound screening; instead, selective screening should be performed by 6-8 weeks of age on infants with risk factors of breech presentation, family history, or history of clinical hip instability. Follow-up of infants with risk factors and normal initial screening should be considered to at least 6 months of age. Brace treatment is a sensible first-line treatment for management of dislocated hips at rest in infants < 6 months of age. Early operative reduction may be considered as there is insufficient evidence to support a protective role for the ossific nucleus in the development of avascular necrosis.

Developmental Dysplasia of Hip: Perspectives in Genetic Screening

Development dysplasia of the hip (DDH) is a complex developmental disorder despite being a relatively common condition mainly caused by incompatibility of the femoral head and the abnormal joint socket. Development dysplasia of the hip describes a wide spectrum of disorders ranging from minor acetabular dysplasia to irreducible dislocation of the hip. Modern medicine still suffers from lack of information about screening and precise genetic examination. Genome wide linkage and association studies have brought significant progress to DDH diagnosis. Association studies managed to identify many candidate (susceptible) genes, such as PAPPA2, COL2A1, HOXD9, GDF-5, and TGFB1, which play a considerable role in the pathogenesis of DDH. Early detection of DDH has a big chance to help in preventing further disability and improve the psychological health and quality of life in those children. This emphasizes the importance to establish a universal screening program along with the genetic counseling.

A genome-wide association study identifies new genes associated with developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is one of the most common congenital malformations and covers a spectrum of hip disorders from mild dysplasia to irreducible dislocation. The pathological mechanisms of DDH are poorly understood, which hampers the development of diagnostic tools and treatments. To gain insight into its disease mechanism, we explored the potential biological processes that underlie DDH by integrating pathway analysis tools and performing a genome-wide association study (GWAS). A total of 406 DDH-associated genes (P < 0.001) were identified by our GWAS using a Chinese Han cohort consisting of 386 DDH cases and 500 healthy controls (Set A). We verified the significant loci (P < 10^-5 ) in another Chinese Han cohort consisting of 574 DDH patients and 569 healthy controls (Set B). An intronic Single Nucleotide Polymorphism (SNP) (rs61930502) showed significant association in Set A and Set B (P = 2.65 × 10^-7 and 2.0 × 10^-4 , respectively). The minor allele, rs61930502-A, which tended to prevent DDH showed a dominant effect. Heat shock 70 kDa protein 8 (HSPA8) showed the most direct interactions with other proteins which were coded by DDH-associated genes in the protein-protein interaction analysis. Interestingly, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested a relation between DDH and the genes involved in type II diabetes mellitus pathway (P = 0.0067). Our genetic and protein interaction evidence could open avenues for future studies of DDH.

Enhanced detection services for developmental dysplasia of the hip in Scottish children, 1997-2013

BACKGROUND

Developmental dysplasia of the hip (DDH) remains common. If detected early, DDH can usually be corrected with conservative management. Late presentations often require surgery and have worse outcomes.

OBJECTIVE

We estimated the risk of undergoing surgery for DDH by age 3 years before and after the introduction of enhanced DDH detection services.

DESIGN

Retrospective cohort study.

SETTING

Scotland, 1997/98-2010/11.

PATIENTS

All children.

METHODS

Using routinely collected national hospital discharge records, we examined rates of first surgery for DDH by age 3 by March 2014. Using a difference in difference analysis, we compared rates in two areas of Scotland before (to April 2002) and after (from April 2005) implementation of enhanced DDH detection services to those seen in the rest of Scotland.

RESULTS

For children born in the study period, the risk of first surgery for DDH by age 3 was 1.18 (95% CI 1.11 to 1.26) per 1000 live births (918/777 375).Prior to April 2002, the risk of surgery was 1.13 (95% CI 0.88 to 1.42) and 1.31 (95% CI 1.16 to 1.46) per 1000 live births in the intervention and non-intervention areas, respectively. In the intervention areas, from April 2005, this risk halved (RR 0.47; 95% CI 0.32 to 0.68). The risk remained unchanged in other areas (RR 1.01; 95% CI 0.86 to 1.18). The ratio for the difference in change of risk was 0.46 (95% CI 0.31 to 0.70).

CONCLUSIONS

The implementation of enhanced DDH detection services can produce substantial reductions in the number of children having surgical correction for DDH.

The incidence of associated abnormalities in patients with sacrococcygeal teratoma

BACKGROUND

Gross genetic causes for SCT are unknown; however, it might be associated with other abnormalities. We assessed the incidence of associated abnormalities in a large national cohort of neonates with SCT and aimed to identify predictive risk factors.

PROCEDURE

The medical records were reviewed of 235 consecutive neonates with SCT treated at the six pediatric surgical centers in the Netherlands from 1970 to 2010. Potential risk factors for associated abnormalities analyzed included sex, gestational age, tumor-volume/histology and Altman-classification.

RESULTS

In 76 patients (32.3%) at least one associated abnormality was diagnosed, with hydronephrosis as the most common (16.2%) and hip dysplasia in 4.3%. Multiple abnormalities were documented for 21 (9.0%). Prematurity and Altman type IV SCT were associated with an increased risk of any associated abnormality. No association between increased tumor-volume and hydronephrosis or hip dysplasia was found. Patients with type IV Altman SCT had a fourfold risk of suffering from hydronephrosis compared to Altman type I SCT.

CONCLUSIONS

SCT was associated with other abnormalities in one-third of children. Some were tumor-related while others were related to prematurity or occurred sporadically. In contrast to clinically obvious anomalies, hip dysplasia or hydronephrosis might be latently present with more subtle clinical presentation. We therefore suggest renal- and hip-ultrasound in all patients, certainly those with Altman type IV SCT.

LEVEL OF EVIDENCE RATING

Level II (retrospective study).

Neonatal screening and selective sonographic imaging in the diagnosis of developmental dysplasia of the hip

Aims

The aim of this prospective cohort study was to evaluate the effectiveness of the neonatal hip instability screening programme.

Patients and Methods

The study involved a four-year observational assessment of a neonatal hip screening programme. All newborns were examined using the Barlow or Ortolani manoeuvre within 72 hours of birth; those with positive findings were referred to a ‘one-stop’ screening clinic for clinical and sonographic assessment of the hip. The results were compared with previous published studies from this unit.

Results

A total of 124 newborns with a positive Barlow or Ortolani manoeuvre, clunk positive, or ‘unstable’ were referred. Five were found to have clinical instability of the hip. Sonographically, 92 newborns had Graf Type I hips, 12 had Graf Type II hips, and 20 had Graf Type IV hips. The positive predictive value (PPV) of clinical screening was 4.0% and the PPV of sonography was 16.1%. This has led to an increased rate of surgery for DDH.

Conclusion

Compared with previously published ten-year and 15-year studies, there has been a marked deterioration in the PPV in those referred with potential instability of the hip. There appears to be a paradox, with rising referrals and a decreasing PPV combined with an increasing rate of surgery in newborns with developmental dysplasia of the hip. Cite this article: Bone Joint J 2018;100-B:806–10.

Genetic Influence in Developmental Dysplasia of the Hip in Saudi Arabian Children Due to GDF5 Polymorphism

Developmental dysplasia of the hip (DDH) is quite common among Saudi Arabian babies. With an objective to assess the presence of SNP rs143383 and the alleles in the GDF5 gene among patients with DDH, parents, and unaffected siblings, we undertook this case-controlled study. We collected and analyzed for a functional single nucleotide polymorphism (SNP) in the 5'-untranslated region of the GDF5 gene (rs143383), 473 blood samples, (100 patients, 200 parents, 73 siblings and 100 healthy controls. We determined the association between the patients' genotype and their fathers', mothers' and siblings' genotype through Chi-square analysis. The majority of those screened possessed the TC genotype, and 61.8% of patients and their fathers had the TT genotype. There was no association between patients' and fathers' genotype, P value < 0.332, 95% CI (0.328-0.346), and between patients' and mothers', P < 0.006, 95% CI (0.004-0.007). When considering DDH patients' and the control group's genotypes, the odds ratios of TT versus other combined (0.641 > 1) and CC versus other combined (0.474 < 1) revealed that the TT genotype has higher risk of developing DDH compared with the CC genotype. The 95 percent confidence interval of TT versus other combined and CC versus other combined is 0.932-2.891 and 0.208-1.078, respectively. For patients' and fathers' genotypes, the odds ratios of TT versus other combined (1.275 > 1) and CC versus other combined (0.815 < 1) indicate that the TT genotype has higher risk of exhibiting DDH compared to the CC genotype. For patients' and siblings' genotypes, the odds ratios of TT versus other combined (1.669) and CC versus other combined (1.048) specify that the TT genotype possesses higher risk of developing DDH compared with the CC genotype. Our study shows that there exists a relationship between GDF5 (SNP rs143383) and DDH in our population. Second, we found for the first time that the genotype TT and the T allele were overly expressed in the patients and the fathers. More studies on the confirmation of this genetic marker for DDH are called for.

The positive predictive value of asymmetrical skin creases in the diagnosis of pathological developmental dysplasia of the hip

Aims

The aim of this study was to identify the association between asymmetrical skin creases of the thigh, buttock or inguinal region and pathological developmental dysplasia of the hip (DDH).

Patients and Methods

Between 1 January 1996 and 31 December 2016, all patients referred to our unit from primary or secondary care with risk factors for DDH were assessed in a "one stop" clinic. All had clinical and sonographic assessment by the senior author (RWP) with the results being recorded prospectively. The inclusion criteria for this study were babies and children referred with asymmetrical skin creases. Those with a neurological cause of DDH were excluded. The positive predictive value (PPV) for pathological DDH was calculated.

Results

A total of 105 patients met the inclusion criteria. There were 71 girls and 34 boys. Only two were found to have pathological DDH. Both also had unilateral limited abduction of the hip in flexion and a positive Galeazzi sign with apparent leg-length discrepancy. Thus, if the specialist examination of a patient with asymmetrical skin creases was normal, the PPV for DDH was 0%.

Conclusion

Isolated asymmetrical skin creases are an unreliable clinical sign in the diagnosis of pathological DDH. Greater emphasis should be placed on the presence of additional clinical signs to guide radiological screening in babies and children. Cite this article: Bone Joint J 2018;100-B:675-9.

Blood Transfusion Incidence, Risk Factors, and Associated Complications in Surgical Treatment of Hip Dysplasia

BACKGROUND

Perioperative bleeding requiring blood transfusion is a known complication of hip dysplasia (HD) surgery. Here we examine rates of, risk factors for, and postoperative complications associated with transfusion during HD surgery.

METHODS

The National Surgical Quality Improvement Program (NSQIP) Pediatric database was queried for patients treated by an orthopaedist from 2012 to 2013. HD cases were categorized by Current Procedural Terminology codes into femoral osteotomies, acetabular osteotomies, combined femoral/acetabular osteotomies, and open reductions. Patients were grouped by comorbidities: neuromuscular (NM) disease (eg, cerebral palsy) group, non-NM with other comorbidity (Other) group, and no known comorbidity (NL) group. Patients were stratified by weight-normalized transfusion volume. Multivariate regression analysis of transfusion association with procedures, demographics, comorbidities, preoperative laboratory values, and 30-day complications was performed.

RESULTS

A total of 1184 HD cases were included. Transfusion rates for the NL, Other, and NM groups, respectively, were 44/451 (9.8%), 61/216 (28.2%), and 161/517 (31.1%). Transfusion volumes (mean±SD) for the NL, Other, and NM groups, respectively, were 8.4±5.4, 13.9±8.8, and 15.5±10.0 mL/kg (P<0.001). Combined osteotomies had the highest transfusion rates in the NM and Other groups (35.7% and 45.8%, respectively), whereas acetabular osteotomies had the highest rate in the NL group (15.8%). Open reductions had the lowest transfusion rate (all groups). Longer operations were independently associated with transfusion (all groups, per hour increase, OR>1.5, P<0.001). Independent patient risk factors included preoperative hematocrit <31% (NM group, OR=18.42, P=0.013), female sex (NL group, OR=3.55, P=0.008), developmental delay (NM group, OR=2.37, P=0.004), pulmonary comorbidity (NM group, OR=1.73, P=0.032), and older age (NL group, per year increase: OR=1.29, P<0.001). In all groups, transfusion was associated with longer hospitalization (P<0.001). We observed a volume-dependent increase in overall complication rate within the Other group for transfusion volumes >15 mL/kg (25.0% vs. 5.4% for <15 mL/kg, P=0.048).

CONCLUSIONS

We identified several risk factors for transfusion in HD surgery. The incidence of transfusion in HD surgery and its association with adverse outcomes warrants development of appropriate patient management guidelines.

LEVEL OF EVIDENCE

Level III-prognostic.

Prevalence of Developmental Dysplasia of the Hip in Chinese Adults: A Cross-sectional Survey

Background:

The prevalence of developmental dysplasia of the hip (DDH) is unknown in China. We aimed to determine the prevalence of DDH in Chinese adults.

Methods:

In this study, we performed a cross-sectional survey of a nationally representative sample of Chinese adults. All participants underwent questionnaire investigation, physical examination, and X-ray examination. Factors associated with DDH were analyzed with logistic regression.

Results:

We invited 29,180 individuals aged 18 years and over to participate, randomly selected from 18 primary sampling units (street districts in urban areas and townships in rural areas). The survey and examination were completed in 25,767 people (10,296 men and 15,471 women). DDH was diagnosed in 391 people, yielding an overall DDH prevalence of 1.52%. Based on this information, we estimate the number of individuals with DDH in China to be approximately 16.05 million. DDH prevalence increased with age (odds ratio = 1.53 [1.03–2.27], P = 0.036), was significantly higher among women than men (2.07% vs. 0.75%, P < 0.001), and was higher among rural residents than urban residents (1.75% vs. 1.29%, P < 0.001). Economic development was independently associated with the presence of DDH. There was no evidence of an association between body mass index alone, education, or current smoking or drinking and risk of DDH (P > 0.05).

Conclusions:

DDH has become an important public health problem. Special attention should be paid to residents with DDH. Screening for DDH should be performed in China.

Whole genome sequencing of pairwise human subjects reveals DNA mutations specific to developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is a common congenital malformation characterized by mismatch in shape between the femoral head and acetabulum, and leads to hip dysplasia. To date, the pathogenesis of DDH is poorly understood and may involve multiple factors, including genetic predisposition. However, comprehensive genetic analysis has not been applied to investigate a genetic component of DDH. In the present study, 10 pairs of healthy fathers and DDH daughters were enrolled to identify genetic hallmarks of DDH using high throughput whole genome sequencing. The DDH-specific DNA mutations were found in each patient. Overall 1344 genes contained DDH-specific mutations. Functional enrichment analysis showed that these genes played important roles in the cytoskeleton, microtubule cytoskeleton, sarcoplasm and microtubule associated complex. These functions affected osteoblast and osteoclast development. Therefore, we proposed that the DDH-specific mutations might affect bone development, and caused DDH. Our pairwise high throughput sequencing results comprehensively delineated genetic hallmarks of DDH. Further research into the biological impact of these mutations may inform the development of DDH diagnostic tools and allow neonatal gene screening.

How to use… Hip examination and ultrasound in newborns

Developmental dysplasia of the hip (DDH) ranges from a clinically detectable dislocation of the hip to radiologically diagnosed hip abnormalities. It is caused by both antenatal and postnatal factors. The Neonatal and Infant Physical Examination Screening Programme recommends that newborns should undergo a hip ultrasound (USS) when risk factor or clinical features suggestive of DDH are present. The aim of hip ultrasonography is to detect DDH early and prevent late complications through early treatment. Here, we discuss how to use hip examination and USS in newborns.

Early childhood anomalies of the hip occur at a similar frequency in patients with idiopathic scoliosis and in healthy individuals – questionnaire for parents

Introduction: Improper hip joint development may lead to numerous unfavourable changes in the musculoskeletal system. The aim of this research was to determine how often adolescents with idiopathic scoliosis and their healthy counterparts experienced anomalies of the hip in their infancy period and to examine the correlation between the occurrence of hip anomalies and idiopathic scoliosis. Material and methods: The research was conducted in medical centres as well as in schools. The parents of adolescents with idiopathic scoliosis and parents of healthy adolescents completed a questionnaire on the basis of their child’s development history included in the medical records book and other medical documentation. Results: 533 questionnaires were taken into consideration, included 145 questionnaires completed by parents of adolescents with scoliosis (121 girls - 13.8 years, SD 1.9; 24 boys - 12.9 years, SD 2.5) and 388 questionnaires from the group of adolescents without scoliosis (194 girls - 13.5 years, SD 2.0; 194 boys - 13.4 years, SD 2.1). No significant differences were noted in the incidence of hip anomalies between the groups of girls and boys with and without scoliosis, no correlations between anomalies of the hip and scoliosis were found (girls χ2=0.840; Cramer V=0.052; p=0.36; boys χ2=1.205; Cramer V=0.074; p=0.27). Conclusions: Hip anomalies such as hip dysplasia, movement asymmetry or range of motion limitations diagnosed in the infancy period did not correlate with idiopathic scoliosis. Further research aimed at a separate analysis of the influence of hip dysplasia on the occurrence of idiopathic scoliosis should be carried out.

Clicky hip alone is not a true risk factor for developmental dysplasia of the hip

AIMS

A clicky hip is a common referral for clinical and sonographic screening for developmental dysplasia of the hip (DDH). There is controversy regarding whether it represents a true risk factor for pathological DDH. Therefore a 20-year prospective, longitudinal, observational study was undertaken to assess the relationship between the presence of a neonatal clicky hip and pathological DDH.

PATIENTS AND METHODS

A total of 362 infants from 1997 to 2016 were referred with clicky hips to our 'one-stop' paediatric hip screening clinic. Hips were assessed clinically for instability and by ultrasound imaging using a simplified Graf/Harcke classification. Dislocated or dislocatable hips were classified as Graf Type IV hips.

RESULTS

The mean age at presentation was 13.8 weeks (12.8 to 14.7). In all 351 out of 362 children (97.0%) had Graf Type I hips (normal) that required no treatment. Nine children (2.5%) had Graf Type II hips but all resolved to Graf Type I hips on follow-up scans. One child (0.3%) had Graf Type III hip dysplasia and one child (0.3%) had an irreducible hip dislocation. The two pathological hips were associated with unilateral limited hip abduction. Mean referrals increased from 12.9 to 23.3 each year (p = 0.002) from the first decade of the study to the second, driven by increasing primary care referrals (5.5 versus 16.7 per year, p < 0.001).

CONCLUSION

Most clicky hips required no treatment other than reassurance to parents. Clicky hips with a normal hip examination should be considered a variant of normal childhood and not a risk factor for DDH. However, an abnormal hip examination including unilateral limited hip abduction should prompt urgent further investigations. Cite this article: Bone Joint J 2017;99-B:1533-6.

Late presentation of developmental dysplasia of the hip

Aims

Despite the presence of screening programmes, infants continue to present with late developmental dysplasia of the hip (DDH), the impact of which is significant. The aim of this study was to assess infants with late presenting dislocation of the hip despite universal clinical neonatal and selective ultrasound screening.

Patients and Methods

Between 01 January 1997 to 31 December 2011, a prospective, longitudinal study was undertaken of a cohort of 64 670 live births. Late presenting dislocation was defined as presentation after three months of age. Diagnosis was confirmed by ultrasound and plain radiography. Patient demographics, referral type, reason for referral, risk factors (breech presentation/strong family history) and clinical and radiological findings were recorded.

Results

There were 31 infants with an irreducible dislocation of the hip, an incidence of 0.48 (95% confidence interval (CI) 0.34 to 0.68) per 1000 live births. Of these, 18 (0.28 (95% CI 0.17 to 0.44) per 1000 live births; 58%) presented late. All infants had a documented normal newborn clinical examination and no abnormality reported in the six to eight week check. Of the 18 late presenting cases 72% (n = 13) had no risk factors: 16 were referred by GPs and two were late due to administrative issues (missed appointments). The mean time to diagnosis was 62.4 weeks (19 to 84).

Conclusion

Despite universal clinical neonatal and selective ultrasound screening, late cases of irreducible hip dislocation still occur. We recommend an update of the national screening programme for DDH, a review of training and education of healthcare professionals involved in the physical examination of neonates and infants, and the addition of a further assessment after the six to eight week check. Cite this article: Bone Joint J 2017;99-B:1250–5.

Screening in Developmental Dysplasia of the Hip (DDH)

Screening for Developmental Dysplasia of the Hip (DDH) is a controversial subject. Screening may be by universal neonatal clinical examination (Ortolani or Barlow manoeuvres) with the addition of sonographic imaging of the hip (selective 'at risk' hips or universal screening in the neonate). In the UK, the NIPE guidelines recommend universal neonatal clinical assessment of the hip joints, a General Practitioner 6-8 week clinical 'hip check' and assessment clinically with sonographic imaging at 4-6 weeks for certain 'at risk' hips for pathological DDH. The effectiveness and difficulties arising from the UK current screening policy (clinical and sonographic) are highlighted. The purpose of the review was to assess the risk factors and efficacy of diagnostic methods in DDH, based on longitudinal cohort studies of 10 years or more.

CONCLUSION

Hip screening in DDH does not meet most of the World Health Organisation's criteria for an effective screening programme and should only be considered as surveillance due to its low sensitivity and positive predictive value (PPV). There is a significant risk of over diagnosis and over treatment. There is no International consensus on screening in DDH. Pathological DDH is mainly a female condition and 'at risk'/General Practitioner screening identifies few pathological cases in male subjects. The General Practitioner 6-8 week 'hip check' has a very low PPV for pathological DDH and is of doubtful value in screening and diagnosis. Unilateral limitation of hip abduction is a time dependent and useful clinical sign in the diagnosis of pathological DDH. The majority of the previously considered 'at risk' factors are not true risk factors with little or no association with pathological DDH.

Utilization of ultrasonography to detect developmental dysplasia of the hip: when reality turns selective screening into universal use

Background

Developmental dysplasia of the hip (DDH) occurs in 3–5 of 1000 live births and is associated with known risk factors. In most countries, formal practice for early detection of DDH entails the combination of risk factor identification and physical examination of the hip, while the golden standard diagnostic instrument is hip ultrasonography (US). This practice is commonly referred to as selective screening. Infants with positive US findings are treated with a Pavlik harness, a dynamic abduction splint.

The objective of our study was to evaluate hip US utilization patterns in Maccabi Healthcare Services (MHS), a large health plan.

Methods

Study population: All MHS members, born between June 2011 and October 2014, who underwent at least one US before the age of 15 months. Study variables: Practice specialty and number of enrolled infants. Positive US result was defined as referral to an abduction splint. Cost was based on Ministry of Health price list. Chi square and correlation coefficients were employed in the statistical analysis.

Results

Of the 115,918 infants born during the study period, 67,491 underwent at least one hip US. Of these, 60.6% were female, mean age at performance: 2.2 months. Of those who underwent US, 625 (0.93%) were treated with a Pavlik harness: 0.24% of the male infants and 1.60% of the female infants (p < 0.001). Analysis of physician practice characteristics revealed that referral to US was significantly higher among pediatricians as compared with general practitioners (60% and 35%, respectively). Practice volume had no influence on referral rate. Direct medical costs of the 107 hip US examinations performed that led to detection of one positive case (treated by Pavlik): US$10,000.

Conclusions

Current pattern of hip US utilization for early detection of DDH resembles universal screening more closely than selective screening. This can inform policy decisions as to whether a stricter selective screening or a formal move to universal screening is appropriate in Israel.

Exome sequencing identified rare variants in genes HSPG2 and ATP2B4 in a family segregating developmental dysplasia of the hip

Background

Developmental dysplasia of the hip (DDH) is a common pathological condition of the musculoskeletal system in infants which results in a congenital and developmental malformation of the hip joint. DDH is a spectrum of pathologies affecting the infant hip ranging from asymptomatic subtle radiographic signs through mild instability to frank dislocations with acetabular dysplasia. A Saudi family with three affected individuals with DDH was identified and genetic analysis was performed to detect the possible genetic defect(s) underlying DDH in the affected members of the family.

Methods

We performed whole genome genotyping using Illumina HumanOmni 2.5 M array and whole exome sequencing (WES) using Nextera Rapid capture kit and Illumina NextSeq500 instrument in four individuals of a family with DDH.

Results

SNP data analysis did not identify any runs of homozygosity and copy number variations. Identity-by-descent (IBD) analysis on whole genome genotyping data identified a shared haplotypes on chromosome 1 in affected individuals. An analysis of the WES data identified rare heterozygous variants in HSPG2 and ATP2B4 genes in the affected individuals. Multiple prediction software predicted that the variants identified are damaging. Moreover, in silico analysis showed that HSPG2 regulates ATP2B4 expression using a variety of transcription factors.

Conclusion

Our results indicate that there might be a functional epistatic interaction between HSPG2 and ATP2B4, and DDH in the family studied is due to a combined effect of both variants. These variants are also present in the asymptomatic mother suggesting that the variants in HSPG2 and ATP2B4 are incompletely penetrant. This study provides the first evidence of digenic inheritance of DDH in a family and extends the spectrum of genetic heterogeneity in this human disorder.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-017-0393-8) contains supplementary material, which is available to authorized users.

Managing Developmental Dysplasia of the Hip

Developmental dysplasia of the hip (DDH) involves a spectrum of hip disorders that affect hip anatomy and development and can range from mild anatomical deformity with a reduced but subluxatable hip to a frankly dislocated hip. It was previously known as congenital dislocation of the hip (CDH) but this name is no longer used due to the fact that the hip may be anatomically abnormal whilst not being dislocated. The key aim of clinical management of DDH is early diagnosis and referral as this can often mean less invasive treatment is possible, and outcomes are significantly improved if treatment is initiated at an early stage and certainly before 6 wk of age.

Sonographic screening for developmental dysplasia of the hip in preterm breech infants: do current guidelines address the specific needs of premature infants?

OBJECTIVE

To assess the association between gestational age versus corrected age at the time of hip ultrasound with findings for developmental dysplasia of the hip (DDH) in preterm breech infants.

STUDY DESIGN

A retrospective medical chart review was conducted to examine hip ultrasounds of 318 premature breech infants for findings associated with DDH.

RESULTS

Positive findings for DDH occurred in 3/135 (2%) of infants <32 weeks gestational age and 17/183 (9%) of infants 32 to <37 weeks gestational age (odds ratio: 0.22, 95% CI: 0.04 to 0.79, P<0.015). No infants born <32 weeks gestational age had abnormal findings for DDH upon follow-up ultrasound. Infants <40 weeks corrected age at the time of hip ultrasound were more likely to have DDH findings compared with infants ⩾44 weeks corrected age (odds ratio: 7.83, 95% CI: 2.20 to 29.65, P<0.001).

CONCLUSION

Current hip ultrasonography policies that include screening of premature breech infants may need to be revised.

An index for diagnosing infant hip dysplasia using 3-D ultrasound: the acetabular contact angle

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common condition that is highly treatable in infancy but can lead to the lifelong morbidity of premature osteoarthritis if left untreated. Current diagnostic methods lack reliability, which may be improved by using 3-D ultrasound.

OBJECTIVE

Conventional 2-D US assessment of DDH has limitations, including high inter-scan variability. We quantified DDH on 3-D US using the acetabular contact angle (ACA), a property of the 3-D acetabular shape. We assessed ACA reliability and diagnostic utility.

MATERIALS AND METHODS

We prospectively collected data from January 2013 to December 2014, including 114 hips in 85 children divided into three clinical diagnostic groups: (1) normal, (2) initially borderline but ultimately normal without treatment and (3) dysplastic requiring treatment. Using custom software, two observers each traced acetabula twice on two 3-D US scans of each hip, enabling automated generation of 3-D surface models and ACA calculation. We computed inter-observer and inter-scan variability of repeatability coefficients and generated receiver operating characteristic (ROC) curves.

RESULTS

The 3-D US acetabular contact angle was reproduced 95% of the time within 6° in the same scan and within 9° in different scans of the same hip, vs. 9° and 14° for the 2-D US alpha angle (P < 0.001). Areas under ROC curves for diagnosis of developmental dysplasia of the hip were 0.954 for ACA and 0.927 for alpha angle.

CONCLUSION

The 3-D US ACA was significantly more reliable than 2-D US alpha angle, and the 3-D US measurement predicted the presence of DDH with slightly higher accuracy. The ACA therefore shows promising initial diagnostic utility. Our findings call for further study of 3-D US in the diagnosis and longer-term follow-up of infant hip dysplasia.

What Is the Impact of Center Variability in a Multicenter International Prospective Observational Study on Developmental Dysplasia of the Hip?

BACKGROUND

Little information exists concerning the variability of presentation and differences in treatment methods for developmental dysplasia of the hip (DDH) in children < 18 months. The inherent advantages of prospective multicenter studies are well documented, but data from different centers may differ in terms of important variables such as patient demographics, diagnoses, and treatment or management decisions. The purpose of this study was to determine whether there is a difference in baseline data among the nine centers in five countries affiliated with the International Hip Dysplasia Institute to establish the need to consider the center as a key variable in multicenter studies.

QUESTIONS/PURPOSES

(1) How do patient demographics differ across participating centers at presentation? (2) How do patient diagnoses (severity and laterality) differ across centers? (3) How do initial treatment approaches differ across participating centers?

METHODS

A multicenter prospective hip dysplasia study database was analyzed from 2010 to April 2015. Patients younger than 6 months of age at diagnosis were included if at least one hip was completely dislocated, whereas patients between 6 and 18 months of age at diagnosis were included with any form of DDH. Participating centers (academic, urban, tertiary care hospitals) span five countries across three continents. Baseline data (patient demographics, diagnosis, swaddling history, baseline International Hip Dysplasia Institute classification, and initial treatment) were compared among all nine centers. A total of 496 patients were enrolled with site enrolment ranging from 10 to 117. The proportion of eligible patients who were enrolled and followed at the nine participating centers was 98%. Patient enrollment rates were similar across all sites, and data collection/completeness for relevant variables at initial presentation was comparable.

RESULTS

In total, 83% of all patients were female (410 of 496), and the median age at presentation was 2.2 months (range, 0-18 months). Breech presentation occurred more often in younger (< 6 months) than in older (6-18 months at diagnosis) patients (30% [96 of 318] versus 9% [15 of 161]; odds ratio [OR], 4.2; 95% confidence interval [CI], 2.3-7.5; p < 0.001). The Australia site was underrepresented in breech presentation in comparison to the other centers (8% [five of 66] versus 23% [111 of 479]; OR, 0.3, 95% CI, 0.1-0.7; p = 0.034). The largest diagnostic category was < 6 months, dislocated reducible (51% [253 of 496 patients]); however, the Australia and Boston sites had more irreducible dislocations compared with the other sites (ORs, 2.1 and 1.9; 95% CIs, 1.2-3.6 and 1.1-3.4; p = 0.02 and 0.015, respectively). Bilaterality was seen less often in older compared with younger patients (8% [seven of 93] versus 26% [85 of 328]; p < 0.001). The most common diagnostic group was Grade 3 (by International Hip Dysplasia Institute classification), which included 58% (51 of 88) of all classified dislocated hips. Splintage was the primary initial treatment of choice at 80% (395 of 496), but was far more likely in younger compared with older patients (94% [309 of 328] versus 18% [17 of 93]; p < 0.001).

CONCLUSIONS

With the lack of strong prognostic indicators for DDH identified to date, the center is an important variable to include as a potential predictor of treatment success or failure.

What Risk Factors and Characteristics Are Associated With Late-presenting Dislocations of the Hip in Infants?

BACKGROUND

Most infants with developmental dysplasia of the hip (DDH) are diagnosed within the first 3 months of life. However, late-presenting DDH (defined as a diagnosis after 3 months of age) does occur and often results in more complex treatment and increased long-term complications. Specific risk factors involved in late-presenting DDH are poorly understood, and clearly defining an associated set of factors will aid in screening, detection, and prevention of this condition.

QUESTIONS/PURPOSES

Using a multicenter database of patients with DDH, we sought to determine whether there were differences in (1) risk factors or (2) the nature of the dislocation (laterality and joint laxity) when comparing patients with early versus late presentation.

METHODS

A retrospective review of prospectively collected data from a multicenter database of patients with dislocated hips was conducted from 2010 to 2014. Baseline demographics for fetal presentation (cephalic/breech), birth presentation (vaginal/cesarean), birth weight, maternal age, maternal parity, gestational age, family history, and swaddling history of patients were compared among nine different sites for patients who were enrolled at age younger than 3 months and those enrolled between 3 and 18 months of age. A total of 392 patients were enrolled at baseline between 0 and 18 months of age with at least one dislocated hip. Of that group, 259 patients were younger than 3 months of age and 133 were 3 to 18 months of age. The proportion of patients with DDH who were enrolled and followed at the nine participating centers was 98%.

RESULTS

A univariate/multivariate analysis was performed comparing key baseline demographics between early- and late-presenting patients. After controlling for relevant confounding variables, two variables were identified as risk factors for late-presenting DDH as compared with early-presenting: cephalic presentation at birth and swaddling history. Late-presenting patients were more likely to have had a cephalic presentation than early-presenting patients (88% [117 of 133] versus 65% [169 or 259]; odds ratio [OR], 5.366; 95% confidence interval [CI], 2.44-11.78; p < 0.001). Additionally, late-presenting patients were more likely to have had a history of swaddling (40% [53 of 133] versus 25% [64 of 259]; OR, 2.053; 95% CI, 1.22-3.45; p = 0.0016). No difference was seen for sex (p = 0.63), birth presentation (p = 0.088), birth weight (p = 0.90), maternal age (p = 0.39), maternal parity (p = 0.54), gestational age (p = 0.42), or family history (p = 0.11) between the two groups. Late presenters were more likely to present with an irreducible dislocation than early presenters (56% [82 of 147 hips] versus 19% [63 of 333 hips]; OR, 5.407; 95% CI, 3.532-8.275; p < 0.001) and were less likely to have a bilateral dislocation (11% [14 of 133] versus 28% [73 of 259]; OR, 0.300; 95% CI, 0.162-0.555; p = 0.002).

CONCLUSIONS

Those presenting with DDH after 3 months of age have fewer of the traditional risk factors for DDH (such as breech birth), which may explain the reason for a missed diagnosis at a younger age. In addition, swaddling history was more common in late-presenting infants. A high index of suspicion for DDH should be maintained for all infants, not just those with traditional risk factors for DDH. Further investigation is required to determine if swaddling is a risk factor for the development of hip dislocations in older infants. More rigorous examination into traditional screening methods should also be performed to determine whether current screening is sufficient and whether late-presenting dislocations are present early and missed or whether they develop over time.

LEVEL OF EVIDENCE

Level III, retrospective study.

Breech presentation is a risk factor for dysplasia of the femoral trochlea

BACKGROUND AND PURPOSE

Instability of the patellofemoral joint is a common disorder in children and young adults. Although it has multifactorial causes, a shallow femoral trochlea is the single most important factor for instability. There is no consensus as to the etiology of trochlear dysplasia. We assessed whether the presentation of the fetus at birth could be a predisposing factor for trochlear dysplasia.

SUBJECTS AND METHODS

We examined 348 knees in 174 newborns using ultrasonography, concentrating especially on the trochlea femoris. We measured the sulcus angle (SA) on a transverse scan. The way of fetal presentation at birth and standard parameters such as sex, gestational age, and length and weight at birth were registered. As breech presentation is a known risk factor for dysplasia of the hip, we also looked for an association between dysplasia of the femoral trochlea and dysplasia of the hips.

RESULTS

The mean SA was 148°. 17 knees in 14 children had an SA of >159°, which was defined as the threshold value for dysplasia. The incidence of breech position in these children was 15-fold higher. Of the different groups of breech positions, a child in frank breech with the knees locked in extension had a 45-fold increased risk of having trochlear dysplasia.

INTERPRETATION

For some newborns, a high sulcus angle can be found at birth, indicating that trochlear dysplasia can be found from birth. Breech presentation with knees extended appears to be a major risk factor for development of trochlear dysplasia.

Developmental dysplasia of the hip: What has changed in the last 20 years?

Developmental dysplasia of the hip (DDH) describes the spectrum of structural abnormalities that involve the growing hip. Early diagnosis and treatment is critical to provide the best possible functional outcome. Persistence of hip dysplasia into adolescence and adulthood may result in abnormal gait, decreased strength and increased rate of degenerative hip and knee joint disease. Despite efforts to recognize and treat all cases of DDH soon after birth, diagnosis is delayed in some children, and outcomes deteriorate with increasing delay of presentation. Different screening programs for DDH were implicated. The suspicion is raised based on a physical examination soon after birth. Radiography and ultrasonography are used to confirm the diagnosis. The role of other imaging modalities, such as magnetic resonance imaging, is still undetermined; however, extensive research is underway on this subject. Treatment depends on the age of the patient and the reducibility of the hip joint. At an early age and up to 6 mo, the main treatment is an abduction brace like the Pavlik harness. If this fails, closed reduction and spica casting is usually done. After the age of 18 mo, treatment usually consists of open reduction and hip reconstruction surgery. Various treatment protocols have been proposed. We summarize the current practice for detection and treatment of DDH, emphasizing updates in screening and treatment during the last two decades.

Concomitant achondroplasia and developmental dysplasia of the hip

Achondroplasia (ACH) is the most common form of hereditary dwarfism and presents with multiple musculoskeletal anomalies but is not normally associated with premature hip arthritis. Developmental dysplasia of the hip (DDH) is a spectrum of disease resulting in shallow acetabular depth and a propensity for chronic femoral subluxation or dislocation; it is among the most common causes of premature arthritis. This case report describes the diagnosis of symptomatic DDH in a patient with ACH and highlights difficulties of primary total hip arthroplasty (THA) as a treatment option. Intraoperative radiographic imaging is advised to ensure proper prosthesis placement. Femoral osteotomy may aid visualization, reduction, and avoidance of soft tissue injury. Concomitant ACH and DDH is a challenging problem that can be successfully treated with modified THA.

Ultrasound for Infants at Risk for Developmental Dysplasia of the Hip

The best screening method for developmental dysplasia of the hip is controversial. Ultrasonography is sensitive, but cost-effectiveness may limit its use. This study assessed whether ultrasound screening would increase in effectiveness if targeted toward infants with established risk factors for developmental dysplasia of the hip and normal findings on physical examination. All ultrasound scans performed at the authors' institution from January 2007 through January 2011 to screen for developmental dysplasia of the hip were reviewed. Infants with risk factors for developmental dysplasia of the hip and normal findings on physical examination by orthopedic faculty or a pediatrician were selected. Of the 530 cases that were reviewed, 217 had risk factors for developmental dysplasia of the hip and normal findings on physical examination. Mean age of the 217 selected patients was 6.9 weeks. Of the patients, 83% were female, 77% had breech presentation, 30% were firstborn children, 13% had intrauterine packaging abnormalities, and 3% had a family history of developmental dysplasia of the hip. Of the 217 infants, 44 had 1 risk factor, 121 had 2 risk factors, 46 had 3 risk factors, and 6 had 4 risk factors. Dynamic ultrasound evaluation showed instability in 17 patients, for a 7.8% incidence of developmental dysplasia of the hip. All 17 patients were treated with a Pavlik harness. The results suggested that selective ultrasound screening may be effective in infants with risk factors and normal findings on physical examination. Selective ultrasound screening changed treatment management in almost 8% of patients and clinical follow-up in 6.5%. Analysis of the cost-effectiveness of screening is needed.

Ultrasound in detection of developmental hip dysplasia in premature born children

Introduction:

Developmental hip dysplasia represents the most common deformation of locomotor system in children. Developmental modulation of the hip is expressed during first year of life which is important for early diagnosis and treatment. Therefore, in the practice, it is very important to set a diagnosis early with application of simple and convenient methods (ultrasound) in order to achieve fast and efficient therapeutical effect and avoid permanent disability.

Aim:

The aim of this paper is to point out the increase of prematurely born infants and their survival thanks to the development of Unit for Intensive Neonatal Care at the Pediatric Clinics in Sarajevo.

Material and methods:

Clinical investigation included 150 infants (77 girls and 73 boys) in whom the developmental hip dysplasia was diagnosed with clinical exam, ultrasound exam and x-ray of the hips. The exams were done in period of January 2012 to August 2014.

Results:

Two groups of patients were formed. The first one consisted of premature infants, total number of 75 (34 girls and 41 boys), with developmental hip dysplasia that was diagnosed at the first exam at the Ultrasound unit of the Pediatric clinics and at the Intensive Neonatal Care Unit of the Pediatric Clinics in Sarajevo. Second (control) group consistsed of patients-on term infants who had diagnosed one of developmental hip dysplasia, total of 75 (43 girls and 32 boys) during first exam in the Ultrasound unit of the Pediatric clinics in Sarajevo.

Conclusion:

The frequency of premature birth is between 5 and 10% of all labors and demonstrates increasing trend. We suggest ultrasound examination of hips in each newborn, term or premature, at the age of 6 weeks after birth.

Treatment of the Developmental Dysplasia of the Hip with an Abduction Brace in Children up to 6 Months Old

Introduction. Use of Pavlik harness for the treatment of DDH can be complicated for parents. Any misuse or failure in the adjustments may lead to significant complications. An abduction brace was introduced in our institution, as it was thought to be easier to use. Aim. We assess the results for the treatment of DDH using our abduction brace in children of 0–6 months old and compare these results with data on treatments using the Pavlik harness. Method. Retrospective analysis of patients with DDH from 0 to 6 months old at diagnosis, performed from 2004 to 2009. Outcomes were rates of reduction of the hip and avascular necrosis of the femoral head (AVN). Follow-up was at one year and up to 4 years old. Results. Hip reduction was successful in 28 of 33 patients (85%), with no AVN. Conclusion. Our results in terms of hip reduction rate and AVN rate are similar to those found in literature assessing Pavlik harness use, with a simpler and comfortable treatment procedure.

Selective ultrasound screening is inadequate to identify patients who present with symptomatic adult acetabular dysplasia

PURPOSE

One goal of neonatal screening for developmental dysplasia of the hip (DDH) is the prevention of late surgery. However, the majority of patients with acetabular dysplasia at skeletal maturity are not diagnosed with DDH during infancy. Selective ultrasound screening may identify patients with neonatal hip instability, but may be ineffective for the prevention of dysplasia presenting in adulthood. The purpose of this study is to identify the prevalence of risk factors for DDH that would have warranted selective ultrasound screening in patients with symptomatic acetabular dysplasia after skeletal maturity.

METHODS

A prospective hip specialty center registry was used to identify 68 consecutive skeletally mature patients undergoing corrective osteotomy for symptomatic acetabular dysplasia. Risk factors for DDH evaluated in all patients included sex, family history of hip osteoarthritis or DDH, breech, method of delivery, previous hip treatments, and birth order. Radiographs [lateral center edge angle (CEA), anterior CEA, Tönnis grade, and Tönnis angle] were measured preoperatively.

RESULTS

Sixty-seven females and one male were identified. No patients were previously diagnosed with DDH or received treatment for their hips. The majority of patients (85.3 %) did not meet selective ultrasound screening guidelines following a stable neonatal hip exam and, therefore, would not have been screened in a selective screening program. Of the findings outside of screening guidelines, 98.5 % were females, 52.9 % were first born, and 36.8 % had a family history of hip osteoarthritis.

CONCLUSIONS

The majority (85.3 %) of patients with symptomatic acetabular dysplasia at skeletal maturity would not have met current recommendations for selective ultrasound screening in the USA had they been born today.

International variance in the treatment of developmental dysplasia of the hip

INTRODUCTION

Developmental dysplasia of the hip (DDH) is the most common congenital musculoskeletal abnormality. Recourse to definitive surgical treatment is not typically taken until over the age of 18-24 months. International consensus regarding age at surgery, degree of dysplasia requiring surgery and type of osteotomy is not available in the literature.

STUDY AIMS

To determine variation in timing and type of osteotomy for persistent DDH across the world.

METHODOLOGY

Senior authors of recent publications pertaining to hip dysplasia were sampled. Participants' practice relating to age and radiological indications for surgery were determined.

RESULTS

Thirty-two surgeons responded from five different geographical regions. No inter-regional consensus was established regarding investigations to determine the need for osteotomy, preferred osteotomy type or ideal age at which to perform an osteotomy.

CONCLUSION

International agreement regarding the surgical management of DDH does not exist. This common congenital condition warrants development of a treatment algorithm.

Immobilized chicks as a model system for early-onset developmental dysplasia of the hip

We have almost no understanding of how our joints take on their range of distinctive shapes, despite the clinical relevance of joint morphogenesis to postnatal skeletal malformations such as developmental dysplasia of the hip (DDH). In this study, we investigate the role of spontaneous prenatal movements in joint morphogenesis using pharmacological immobilization of developing chicks, and assess the system as a suitable model for early-onset hip dysplasia. We show that, prior to joint cavitation, the lack of dynamic muscle contractions has little impact on the shape of the hip joint. However, after the timepoint at which cavitation occurs, a dramatic effect on hip joint morphogenesis was observed. Effects in the immobilized chicks included flattening of the proximal femur, abnormal orientation of the pelvis relative to the femur and abnormal placement and coverage of the acetabulum. Although many clinical case studies have identified reduced or restricted movement as a risk factor for DDH, this study provides the first experimental evidence of the role of prenatal movements in early hip joint development. We propose that the immobilized chick embryo serves as a suitable model system for the type of early-onset DDH which arises due to neuromuscular conditions such as spinal muscular atrophy.