Avascular necrosis rate in early reduction after failed Pavlik harness treatment of developmental dysplasia of the hip

Femoral nerve palsy during Pavlik harness treatment for developmental dysplasia of the hip is not an indication for harness abandonment

Objectives

The aim of this study was to report the incidence of femoral nerve palsy in developmental dysplasia of the hip children treated with Pavlik harness, to identify any possible associated risk factors, and to evaluate its outcome without any specific strap release.

Methods

A retrospective chart review was conducted on all cases of femoral nerve palsy in a consecutive series of children who underwent Pavlik harness treatment for developmental dysplasia of the hip. In unilateral cases, the developmental dysplasia of the hip was compared to the contralateral side. All hips with femoral nerve palsy were compared to the remaining hips of the series and any possible risk factor for paralysis was recorded.

Results

In total, 53 cases of femoral nerve palsy of various severity were identified from a group of 473 children with 527 hips treated for developmental dysplasia of the hip at an average age of 3.9 months. However, 93% occurred during the first 2 weeks of treatment. Femoral nerve palsy was more common in older and larger children with the most severe Tonnis type, and a hip flexion angle in the harness above 90° (p < 0.03 for all). All of them resolved spontaneously before completion of treatment without any specific measures. We found no correlation between the presence of femoral nerve palsy or the time taken for spontaneous resolution and treatment failure using the harness.

Conclusion

Femoral nerve palsy is most observed with higher Tonnis types and high hip flexion angles in the harness, but its presence by itself is not predictive of treatment failure. It resolves spontaneously before completion of treatment and does not require any strap release or harness discontinuation.

Level of evidence

Level III.

Closed reduction and plaster immobilization: an alternative solution for patients with developmental dysplasia of the hip who failed Pavlik harness treatment

BACKGROUND

The current study aims to investigate the clinical efficacy of closed reduction and cast immobilization for patients with developmental dysplasia of the hip (DDH) who failed Pavlik harness treatment.

METHODS

Patients with DDH who underwent cast immobilization under general anaesthesia after the failure of the Pavlik harness or Tübingen brace treatment between January 2015 and December 2020 were retrospectively recruited. General information, including Graf classification of initial diagnosis, initial treatment, age of cast immobilization, IHDI classification, AI index, avascular necrosis (AVN), and residual dysplasia, was collected. The incidence of AVN and late acetabular dysplasia (LACD) was also estimated. Moreover, factors related to AVN and LACD were investigated by multiple logistic regression analysis.

RESULTS

Thirty-four patients (47 hips) were finally included in the current study. Of these patients, 31 hips (66.0%) were successfully treated with closed reduction and cast immobilization. Open reduction was successfully performed in 16 hips (34.0%). Till the latest follow-up, LACD and AVN were found in 13 (27.7%) and 10 (21.3%) hips, respectively. In the open reduction group, type III and IV of the IHDI classification and type IV of the Ultrasound Graf classification were significantly higher when compared with the closed reduction group. Multiple logistic regression showed that failure of closed reduction was related to the initial types of the Ultrasound Graf and IHDI classifications.

CONCLUSIONS

Although the success rate of closed reduction after early harness failure in DDH is only 66%, we still advocate closed reduction as a first-line treatment for children who have failed sling treatment. Even if closed reduction fails, open reduction can still achieve acceptable results.

Radiological predictors associated with success of treatment for developmental dysplasia of hip using the Pavlik harness: A retrospective study

BACKGROUND

While various predictors of treatment outcome of Pavlik harness have been reported, appropriate indications for treatment and relationships between patient characteristics and outcome are unclear. The present study aimed to identify radiological predictors for successful Pavlik harness treatment of DDH at the initiation of treatment and investigate the progression of radiological characteristics after successful treatment.

METHODS

One-hundred-forty-two of 527 infants who visited our hospital for secondary screening of DDH were treated with the Pavlik harness. One-hundred-eight hips of 108 infants experienced successful treatment and could be followed up until 3 years of age (group S); treatment was unsuccessful within the first 2 weeks for 22 hips of 21 infants (group F). We investigated the Graf classification and radiological parameters.

RESULTS

We observed the ipsilateral-side measurements of distance A and B as defined by Yamamuro and Chene's method to be significantly smaller and greater, respectively, in group F compared with those of group S. Group F tended to exhibit the smaller distance A and larger distance B compared to the group S among the same Graf type. The cut-off values for successful treatment at were >7.4 mm at initiation of treatment for distance A and <11.2 mm for distance B. The acetabular index (AI) of the ipsilateral side at the initiation of treatment was significantly correlated with that at 1 and 3 years of age. Patients with an AI of >32° at the initiation of harness treatment were more likely to exhibit hip dysplasia at 3 years of age.

CONCLUSIONS

Radiographic parameters prior to the Pavlik harness could be predictors of treatment failure and DDH in the future. This study showed that AI at the initiation of treatment is associated with residual acetabular dysplasia, suggesting that radiographic assessment may be useful even considering the risks associated with radiation exposure.

Impact of Failed Pavlik Harness Treatment on the Outcomes Following Closed or Open Reduction in Developmental Dysplasia of the Hip

PURPOSE

To investigate the impact of failed Pavlik harness (PH) treatment on the outcomes following closed reduction (CR) or open reduction (OR) in developmental dysplasia of the hip (DDH).

METHODS

Ninety-three DDH patients treated with CR or OR were enrolled. One group of which received previous PH treatment (F group) and the other (L group) not. The clinical outcomes were evaluated according to McKay's criteria. Radiographs were evaluated for acetabular index (AI) and the degree of dislocation of the hips.

RESULTS

A higher rate of CR was found in F group (P = 0.034). Before CR/OR, the mean AI in F group was significantly lower than that in L group (P = 0.000), while at the last follow-up, the AIs in both groups were all improved. In F group, there were 7 (16.67%), 18 (42.86%) and 17 (40.48%) hips were classified as Graf type II, III and IV pathologic changes, respectively, when PH treatment started, while the corresponding data were 17 (40.48%), 17 (40.48%) and 8 (19.05%) after PH treatment (P = 0.024). At the last follow-up, no significant difference was found concerning the complications between the two groups (P > 0.05).

CONCLUSIONS

PH treatment, even if failed, may have the ability of accelerating the development of the acetabulum and increasing the rate of successful CR. Thus we advocate a trial of PH treatment for all DDH patients less than 6 months of age. Meanwhile, a close monitoring by dynamic ultrasonography is required due to the risk of AVN.

Evaluation of the short-term curative effect of closed reduction in the treatment of developmental dysplasia of the hip based on three-dimensional magnetic resonance imaging finite element analysis

Background

Based on the Digital Imaging and Communications in Medicine (DICOM) data of three-dimensional magnetic resonance imaging (3D-MRI), finite element models of the hip joints of children with developmental dysplasia of the hip were established. The primary objectives included simulation and analysis of the finite element model pre- and post-closed reduction under different stances and loads, and evaluation of the size and distribution of von Mises stress in the acetabulum and femoral head pre- and post-operation and the short-term effects.

Methods

Acetabular index measurements of both the unaffected and affected sides were conducted, alongside International Hip Dysplasia Institute (IHDI) classification of the affected hip. Establishing the finite element model of both the affected and unaffected hips was based on the 3D-T1WI sequence DICOM data, using Mimics, 3-matic, and Ansys software, before and after closed reduction surgery. The size and distribution data of von Mises stress on the affected side of the acetabulum and femoral head were collected pre- and post-operation.

Results

The study indicated that the increasing acetabular index of the affected hip was directly proportional to the increasing severity based on IHDI classification (P < 0.05). Preoperative IHDI classification significantly correlated with the von Mises stress (r = 0.560–0.569, 0.562–0.564, P < 0.05). Under different stances and load conditions, the von Mises stress on the affected side post-operation was lower than that noted pre-operation (P < 0.01), while that on the acetabulum increased proportionally to the load. Although the magnitude and distribution of von Mises stress on the affected side of the acetabulum were similar to those on the healthy side post-operation, there were statistical differences between the two (P < 0.01). The von Mises stress of the lateral column of the femoral head post-operation was significantly lower than that noted pre-operation (P < 0.01). While the high-stress points of the lateral column disappeared post-operation, the von Mises stress was evenly distributed in the femoral head.

Conclusions

The 3D-MRI finite element could provide the von Mises stress value and distribution characteristics of the acetabulum and femoral head pre- and post-operation. Closed reduction can, therefore, improve the size and distribution of von Mises stress on the affected acetabulum and femoral head.

Principles of Bracing in the Early Management of Developmental Dysplasia of the Hip

Bracing is considered a gold standard in treating Developmental Dysplasia of the Hip (DDH) in infants under 6 months of age with reducible hips. A variety of braces are available that work on similar principles of limiting hip adduction and extension. This paper summarises the current evidence regarding bracing in DDH. Most of the literature pertains to the Pavlik harness (PH) and there are few studies for other brace types. Bracing eliminates dislocating forces from the hamstrings, the block to reduction of the psoas and improves the muscle line of pull to stabilise the hip joint. Recent studies have shown no benefit in bracing for stable dysplasia. The rates of PH treatment failure in Ortolani-positive hips have been reported to be high. Barlow positive hips have lower Graf grades and are more amenable to PH treatment. There is consensus that the earlier the diagnosis of DDH and initiation of PH treatment, the better the outcome. Failure rates due to unsuccessful reduction and AVN are higher with treatment initiated after age 4-6 months. Studies have shown no benefits of staged weaning of braces. While there is no maximum time in brace, current consensus suggests a minimum of 6 weeks. The key to successful bracing lies in education and communication with the family.

Should closed reduction of the dislocated hip be attempted after failed Pavlik harness treatment in developmental dysplasia of the hip?

Aims

To determine the likelihood of achieving a successful closed reduction (CR) of a dislocated hip in developmental dysplasia of the hip (DDH) after failed Pavlik harness treatment We report the rate of avascular necrosis (AVN) and the need for further surgical procedures.

Methods

Data was obtained from the Northern Ireland DDH database. All children who underwent an attempted closed reduction between 2011 and 2016 were identified. Children with a dislocated hip that failed Pavlik harness treatment were included in the study. Successful closed reduction was defined as a hip that reduced in theatre and remained reduced. Most recent imaging was assessed for the presence of AVN using the Kalamchi and MacEwen classification.

Results

There were 644 dislocated hips in 543 patients initially treated in Pavlik harness. In all, 67 hips failed Pavlik harness treatment and proceeded to arthrogram (CR) under general anaesthetic at an average age of 180 days. The number of hips that were deemed reduced in theatre was 46 of the 67 (69%). A total of 11 hips re-dislocated and underwent open reduction, giving a true successful CR rate of 52%. For the total cohort of 67 hips that went to theatre for arthrogram and attempted CR, five (7%) developed clinically significant AVN at an average follow-up of four years and one month, while none of the 35 hips whose reduction was truly successful developed clinically significant AVN.

Conclusion

The likelihood of a successful closed reduction of a dislocated hip in the Northern Ireland population, which has failed Pavlik harness treatment, is 52% with a clinically significant AVN rate of 7%. As such, we continue to advocate closed reduction under general anaesthetic for the hip that has failed Pavlik harness.

Cite this article: Bone Jt Open 2021;2(8):594–598.

The incidence of avascular necrosis following a cohort of treated developmental dysplasia of the hip in a single tertiary centre

PURPOSE

Avascular necrosis (AVN) may occur following treatment for developmental dysplasia of the hip (DDH). The primary aim of this study was to identify the incidence of AVN in a cohort of patients treated for DDH. Secondary aims were to classify AVN using available classification systems, analyze the correlation between the systems and investigate their relationship with the age at diagnosis of DDH.

METHODS

An 11-year retrospective study was carried out at a single tertiary centre, using data from the clinical portal (patient records database) and IMPAX (system used to store plain radiographic images). Clinical details (patient demographics and outcomes) and plain radiographic images were used to identify cases of DDH and categorize cases of AVN using available classification systems: Tonnis and Kuhlmann, Kalamchi and McEwen, Bucholz and Ogden and Salter. Severin was used to assess final clinical outcome.

RESULTS

In total, 405 (522 hips) cases of DDH were identified, of which 213 resolved without treatment, 93 were treated conservatively and 99 surgically. Only treated cases were included in the analysis (n = 192). AVN (45/99; 45.5%) was found to occur only postoperatively. A positive correlation was present between age at presentation and severity of AVN as classified according to Salter's criteria (chi-squared p value < 0.01).

CONCLUSION

AVN incidence was 23.4% (45/192) and only occurred in surgically treated patients. Older age at diagnosis was associated with a higher incidence of AVN, as defined according to Salter's criteria. The classification systems appeared to show no correlation amongst each other (p-value < 0.01).

LEVEL OF EVIDENCE

III - Retrospective cohort study.

Recommendations for early diagnosis of Developmental Dysplasia of the Hip (DDH): working group intersociety consensus document

This consensus document has been prepared by a multidisciplinary group of experts (Paediatricians, Radiologists, Paediatric Orthopaedics) and it is mainly aimed at paediatricians, hospitals and primary care providers. We provide recommendations for the early diagnosis and treatment of Developmental Dysplasia of the Hip (DDH) and indications on its management.

The long noncoding RNA H19 attenuates force-driven cartilage degeneration via miR-483-5p/Dusp5

Developmental dysplasia of the hip (DDH) is a common hip disease characterized by abnormal development of the acetabulum and femoral head. In most cases, DDH ultimately leads to osteoarthritis. Anomalous biomechanical force plays an important role in cartilage degeneration in DDH. However, in addition to mechanical wear, the underlying molecular mechanisms in cartilage degeneration in DDH remain unclear. This study analyzed the effect of long noncoding RNA (lncRNA)-H19 on DDH cartilage degradation. To elucidate the specific role of lncRNA H19, we established an intermittent cyclic mechanical stress (ICMS) cell force model to simulate abnormal biomechanical environment in vitro. Then, the roles of lncRNA-H19 were also determined in vivo by establishing a model of swaddling DDH. We observed that patients with DDH possessed low levels of lncRNA-H19, COL2A1, and Aggrecan but high levels of MMP3 and Adamts5. The same results were also obtained in a DDH rat model. Furthermore, the data suggested that ICMS promoted cartilage degeneration and caused reorientation of the cytoskeleton, and lncRNA H19 helped inhibit cartilage degeneration. Bioinformatics analysis and lncRNA sequencing were performed, and luciferase assays showed that lncRNA H19 and Dusp5 are both direct targets of miR-483-5p. Moreover, Dups5 plays a negative role in ICMS-induced cartilage degradation by activating the Erk and p38 pathways. In vivo, lncRNA H19 had protective effects on the swaddling DDH model. These findings indicate that lncRNA-H19 played a positive role in cartilage degradation in DDH through the lncRNA H19/miR-483-5p/Dusp5 axis.

A Single Approach to Arthroscopic Reduction and Debridement for Developmental Dislocation of the Hip in 12 Infants

Background

Developmental dislocation of the hip (DDH) results in osteoarthritis in infants and children. This study aimed to investigate the effects of a single approach to arthroscopic reduction and debridement on clinical outcome in 12 infants with DDH.

Material/Methods

Twelve infants with irreducible DDH underwent single approach arthroscopic reduction and debridement followed by the use of a frog-leg position plaster cast with fixed flexion and abduction of the hips combined with external fixation for 6–8 weeks. Magnetic resonance imaging (MRI) or plain X-ray images were analyzed. Intra-articular obstructive factors for reduction were evaluated. The safety angle, medialization rate of the femoral head, and the acetabular angle were measured before and after arthroscopic reduction.

Results

Imaging showed that the signs of DDH were significantly improved following arthroscopic reduction. Obstructive factors included hypertrophy of the round ligament, fibrous tissue and fat in the acetabular base, arthrocapsular constriction, and varus deformity of the hip. The safety angle was significantly increased following arthroscopic reduction (53.5°) compared with the safety angle before treatment (18.5°) (p<0.05). Medialization of the femoral head was significantly increased (127%) compared with that before treatment (72%) (p<0.05). Arthroscopic reduction significantly reduced the acetabular angle (25°) compared with that before treatment (37.5°) (p<0.05).

Conclusions

Single approach arthroscopic reduction and debridement was an effective method for treating DDH that significantly improved the medialization rate of the femoral head, acetabular angle, and the outcome of external fixation when a plaster cast was used with fixed flexion and abduction of the 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.

Periacetabular Osteotomy Performed with Imageless Computer-Assisted Navigation: Case Report

Periacetabular osteotomy (PAO) is an effective surgical treatment for developmental hip dysplasia. The goal of PAO is to reorient the acetabulum to increase acetabular coverage of the femoral head, as well as to reduce contact pressures within the hip joint. The primary challenge of PAO is to accurately achieve the desired acetabular fragment orientation, while maximizing containment and congruency. As key parts of the procedure are performed out of direct field of view of the surgeon, combined with this challenge of precise spatial orientation, there is a potential role for technologies such as surgical navigation. Adjunctive technology may provide information on the orientation of repositioned acetabulum and may offer a useful assist in performing PAO. Here, we present a case of developmental dysplasia of the hip treated via PAO with the addition of an imageless computer navigation device. Surgery was successful, and, at 3 months after procedure, the patient was progressing well. To our best knowledge, this is the first case using imageless computer-assisted navigation in PAO surgery.

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.

Closed Reduction for Developmental Dysplasia of the Hip: Early-term Results From a Prospective, Multicenter Cohort

BACKGROUND

Closed reduction (CR) is a common treatment for infantile developmental dysplasia of the hip. The purpose of this observational, prospective, multicenter study was to determine the early outcomes following CR.

METHODS

Prospectively collected data from an international multicenter study group was analyzed for patients treated from 2010 to 2014. Baseline demographics, clinical exam, radiographic/ultrasonographic data, and history of previous orthotic treatment were assessed. At minimum 1-year follow-up, failure was defined as an IHDI grade 3 or 4 hip and/or need for open reduction. The incidence of avascular necrosis (AVN), residual dysplasia, and need for further surgery was assessed.

RESULTS

A total of 78 patients undergoing CR for 87 hips were evaluated with a median age at initial reduction of 8 months (range, 1 to 20 mo). Of these, 8 hips (9%) were unable to be closed reduced initially. At most recent follow-up (median 22 mo; range, 12 to 36 mo), 72/79 initially successful CRs (91%) remained stable. The likelihood of failure was unaffected by initial clinical reducibility of the hip (P=0.434), age at initial CR (P=0.897), or previous treatment in brace (P=0.222). Excluding those hips that failed initial CR, 18/72 hips (25%) developed AVN, and the risk of osteonecrosis was unaffected by prereduction reducibility of the hip (P=0.586), age at CR (P=0.745), presence of an ossific nucleus (P=0.496), or previous treatment in brace (P=0.662). Mean acetabular index on most recent radiographs was 25 degrees (±6 degrees), and was also unaffected by any of the above variables. During the follow-up period, 8/72 successfully closed reduced hips (11%) underwent acetabular and/or femoral osteotomy for residual dysplasia.

CONCLUSIONS

Following an initially successful CR, 9% of hips failed reduction and 25% developed radiographic AVN at early-term follow-up. History of femoral head reducibility, previous orthotic bracing, and age at CR did not correlate with success or chances of developing AVN. Further follow-up of this prospective, multicenter cohort will be necessary to establish definitive success and complication rates following CR for infantile developmental dysplasia of the hip.

LEVEL OF EVIDENCE

Level II-prospective observational cohort.

The H19/let-7 feedback loop contributes to developmental dysplasia and dislocation of the hip

Developmental dysplasia and dislocation of the hip (DDH) is the most common type of lower limb deformity in pediatric orthopedics. The mechanism of the signaling pathway has been studied in depth. However, the role of epigenetic regulation, such as lncRNA, is still far from clear. In this study, we successfully established a rat model of DDH and demonstrated that H19 was down-regulated in the development of DDH. Further, we constructed H19 knockdown (KD) and overexpression chondrocytes. H19 KD suppressed the proliferation of normal chondrocytes, while overexpression of H19 promoted cell proliferation of DDH chondrocytes. Finally, we revealed that H19 bound to let-7 and inhibited its function, acting as a competing endogenous RNA. Down-regulation of H19 is closely associated with DDH progression and H19 is an important epigenetic factor that regulates the proliferation of chondrocytes. H19 may thus be a potential clinical marker for DDH diagnosis and treatment.

Treatment of developmental dysplasia of the hip with the Pavlik harness in children under six months of age: indications, results and failures

PURPOSE

The aim of this article is to review the current concepts in the indications, results and failure causes of the treatment of developmental dysplasia of the hip (DDH) with the Pavlik harness.

METHODS

The reported variables influencing the outcome in the Pavlik harness treatment were analyzed.

RESULTS

Significant discrepancies about the clinical and radiological outcomes, the rates of failure and complications as well as the variables influencing the treatment outcome occur in the published studies due to the heterogeneity of the data and the differences in the methods used. The overall short-, mid- or long-term success rate of the treatment ranges from 45% to 100% and it is commonly over 75%. The rate of osteonecrosis of the femoral head ranges from 1% to 30%. Age, gender, laterality, radiological or clinical severity of the initial hip pathology and parents' compliance are the commonly reported determinants of failure of the treatment.

CONCLUSION

The failure in treatment with the Pavlik harness is multifactorial, initial type of hip dysplasia being the most prominent followed by the treatment initiation age. This type of treatment cannot be considered as the best option in Graf IV hips (hip ultrasonography) or highly dislocated hips (plain radiography) and in infants older than three months of age, as the risk of failure and development of complications including osteonecrosis and femoral nerve palsy seem to increase in such circumstances. Large-scale, comparative studies including homogenous data are needed to answer the unsolved questions concerning indications.

Pavlik Harness Disease Revisited: Does Prolonged Treatment of a Dislocated Hip in a Harness Adversely Affect the α Angle?

BACKGROUND

Current dogma contends that prolonged treatment of a dislocated hip in Pavlik harness beyond 3 weeks will cause "Pavlik harness disease." To our knowledge, however, no previous studies have documented objective morphologic changes to the acetabulum from continued treatment of a persistently dislocated hip.

METHODS

We retrospectively reviewed a consecutive series of infants with developmental dysplasia of the hip, below 6 months old, who failed Pavlik treatment from a single, tertiary-care pediatric hospital and a multicenter, international study group. Inclusion criteria were dislocated hips confirmed by ultrasound (both initially and at Pavlik termination) and a minimum of 2 ultrasounds during harness treatment at least 3 weeks apart. As a global measure of acetabular morphology, α angle (AA) was compared between initial and final ultrasound. The final means of obtaining successful hip reduction was recorded from the medical records.

RESULTS

Forty-nine hips in 38 patients were identified. Median age at Pavlik initiation was 4 weeks (range, 0 to 18 wk); median time in harness was 6 weeks (range, 3 to 14 wk). Surprisingly, a mean of 4 degrees improvement in AA (95% CI, 2-6 degrees; P=0.001) was observed between first and final ultrasound. We found no difference in AA change between those in harness 3 to 5 weeks and those with prolonged wear >5 weeks (P=0.817). There was no significant association between change in AA and time in harness (P=0.545), age at Pavlik initiation (P=0.199), clinical reducibility of the hip (P=0.202), or initial percent femoral head coverage (P=0.956). Following harness failure, 22/49 hips (45%) were successfully treated with rigid abduction bracing, 16 (33%) by closed reduction/spica casting, and 10 (20%) by open reduction; 1 hip (2%) spontaneously reduced and required no further treatment.

CONCLUSIONS

On the basis of the lengths of harness treatment in our series, most hips did not exhibit negative changes in the acetabular AA in response to prolonged treatment of a dislocated hip in harness. Furthermore, 80% of hips failing Pavlik treatment were successfully reduced through closed means, indicating that subsequent treatment was not compromised.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

Investigating the need for routine ultrasound screening to detect developmental dysplasia of the hip in infants born with breech presentation

Objectives

Breech presentation is a recognized risk factor for developmental dysplasia of the hip (DDH). Within North America, there is a lack of consensus on screening guidelines for DDH in infants with a negative physical examination of the hips. This study evaluates the need for ultrasound screening in all breech born infants to detect DDH and whether this is influenced by gender, gestational age and mode of delivery.

Methods

A retrospective chart review was conducted to identify breech born infants who underwent routine hip ultrasound to detect DDH between 2010 and 2015. Patients were grouped by physical exam and ultrasound findings and compared based on gender, gestational age and mode of delivery.

Results

Three hundred and eighteen patients were identified (191 female, 127 male; 26 preterm, 57 late preterm, 235 term; 263 caesarean section delivery, 55 vaginal delivery). Three hundred and eight patients had a negative physical exam of which 27 were diagnosed with DDH based on screening ultrasound with females predominant (P<0.05). 12.50% of females with a negative physical exam had DDH compared to 3.23% of males (P<0.05). There was no difference in the rate of DDH detected by screening ultrasound based on gestational age (P=0.94) or mode of delivery (P=0.59).

Conclusions

The diagnosis of DDH in breech born infants by screening ultrasound in those with a negative physical exam of the hips is more predominant in females, with no apparent association with gestational age or mode of delivery. Future analyses with larger sample sizes are needed before conclusions can be made on screening protocols.

Guided bone regeneration using a bone tissue engineering complex consisting of a poly-dl-lactide membrane and bone mesenchymal stem cells

Developmental dysplasia of the hip (DDH) is one of the most common diseases encountered in pediatric orthopedic departments. Current treatment strategies seek to improve acetabular coverage, the principal defect of acetabular dysplasia, but are not very successful. We developed a guided bone regeneration (GBR) strategy to improve acetabular coverage via bone tissue engineering (BTE). Poly-dl-lactide (PDLLA) membranes were seeded with bone marrow mesenchymal stem cells (BMSCs) to form a BTE complex, which was then implanted into the superior margin of the acetabulum in a rabbit DDH model. Twelve weeks later, a small amount of high-density shadowing was evident on X-rays of the superior margin of the acetabulum, specimens of which exhibited new bone formation. Micro-computed tomography yielding three-dimensional images revealed that new bone had formed in the superior acetabulum, the basal part of which had fused with (and thus reconstructed) the autogenous bone, and new trabecular bone featuring transverse interlacing was evident in the interior of the hip. No clear evidence of bone formation was observed in rabbits that underwent sham operations or that were implanted with PDLLA only. Thus, it may be possible to improve acetabular coverage via BTE-based bone regeneration.

Presence of the Ossific Nucleus and Risk of Osteonecrosis in the Treatment of Developmental Dysplasia of the Hip: A Meta-Analysis of Cohort and Case-Control Studies

BACKGROUND

Concern for increased risk of osteonecrosis in hips with an absent ossific nucleus has led some surgeons to delay reduction in the treatment of developmental dysplasia of the hip (DDH) until the ossific nucleus is present. A previous meta-analysis reported a potential protective effect against high-grade osteonecrosis (II to IV) when the ossific nucleus was present. With a greater number of publications on this topic, revisiting this analysis is warranted. The aim of this meta-analysis was to systematically review and analyze the best clinical evidence regarding the association between the status of the ossific nucleus and development of osteonecrosis following the treatment of DDH.

METHODS

MEDLINE, Embase, and Cochrane databases were systematically searched for studies including the status of the ossific nucleus and rate of osteonecrosis after open and closed reductions for the treatment of DDH. Study characteristics and risk estimates were extracted. Study quality was assessed using the Newcastle-Ottawa Scale. Pooled effect estimates were calculated using a random-effect model. Meta-regression assessed the relationships of reduction method, study quality, mean age at reduction, surgical approach, method of ossific nucleus assessment, and duration of follow-up to the odds of osteonecrosis.

RESULTS

In the 21 observational studies (18 retrospective, 3 prospective) that were included, osteonecrosis developed in 20.4% of the hips in which the ossific nucleus was present at reduction compared with 21.2% of the hips in which the ossific nucleus was absent. Presence of the ossific nucleus was not associated with decreased odds of any grade of osteonecrosis (odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.43 to 1.12) or of more severe osteonecrosis of Grades II to IV (OR = 0.70, 95% CI = 0.30 to 1.17). Meta-regression did not show any effect of the mean age at reduction, reduction method, surgical approach, study quality, minimum or mean duration of follow-up, method of ossific nucleus imaging, or osteonecrosis classification system on the relationship between presence of the ossific nucleus and the risk of osteonecrosis.

CONCLUSIONS

The current literature does not support the hypothesis that presence of the ossific nucleus at reduction is associated with lower risk of osteonecrosis. Prospective studies with long-term follow-up and blinded assessors are warranted to optimally evaluate the relationship between potential risk factors and the development of osteonecrosis.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Risk factors for avascular necrosis after closed reduction for developmental dysplasia of the hip

PURPOSE

The purpose of this study was to identify and evaluate risk factors of avascular necrosis (AVN) after closed treatment for developmental dysplasia of the hip (DDH).

METHODS

A retrospective review of children diagnosed with DDH at a tertiary-care children's hospital between 1986 and 2009 was performed. The presence of AVN was assessed according to Salter's classification system.

RESULTS

Eighty-two affected hips in 70 children with an average age of 10 months at closed reduction (range 1-31 months) and 5 years (range 2-19 years) of follow-up met the inclusion criteria. Twenty-nine (of 82, 35 %) affected hips developed AVN. The use of pre-reduction traction (p = 0.019) increased the risk of AVN, while preoperative Pavlik harness or brace trial (p = 0.28), presence of ossific nucleus at the time of closed reduction (p = 0.16), and adductor tenotomy (p = 0.37) were not significant factors. Laterality (right vs. left) was also not a significant risk factor (p = 0.75), but patients who underwent closed reduction for bilateral DDH were less likely to develop AVN (p = 0.027). Overall, the degree of abduction did not affect the rate of AVN (p = 0.87). However, in patients treated with closed reduction younger than 6 months of age, the rate of AVN was increased with abduction ≥50° (9/15, 60 %) compared to abduction <50° (0/8, 0 %) (p = 0.007). Patients who developed AVN were more likely to require subsequent surgery (p = 0.034) and more likely to report a fair/poor clinical outcome (p = 0.049).

CONCLUSIONS

The risk of AVN (35 %) following closed reduction and spica casting for DDH is high. The degree of abduction in spica casts appears to be a risk factor in patients ≤6 months old. The authors recommend that abduction in spica casts should be limited to <50° in children younger than 6 months of age.

LEVEL OF EVIDENCE

IV.

Surgical Outcomes of Developmental Dysplasia of the Hip With or Without Prior Failed Closed Reduction

BACKGROUND

Osteonecrosis of the femoral head is a major complication in the treatment of developmental dysplasia of the hip (DDH). Redislocation and secondary surgeries were regarded as risk factors of osteonecrosis. This study aims to clarify whether prior failed closed reduction is a risk factor of osteonecrosis in subsequent surgery.

METHODS

We retrospectively studied 124 patients treated by open reduction and pelvic osteotomy for unilateral DDH before 3 years old. Twenty-five patients had failed closed reduction before the surgery (secondary surgery group), and the other 99 patients had the same surgery as the first treatment (primary surgery group). Osteonecrosis was defined by broadening of femoral neck and fragmentation of epiphysis in the first 3 years after operation. The background data and rate of osteonecrosis were compared between the 2 groups using t test and χ2 test.

RESULTS

Age at surgery and Tönnis grade were not significantly different between the 2 groups. Broadening of the femoral neck was observed in 63 of the 99 hips (63.6%) in the primary surgery group and 7 of the 25 hips (28.0%) in the secondary surgery group (P=0.001). Rate of epiphyseal fragmentation was 34% in primary surgery group and 24% in secondary surgery group (P=0.323).

CONCLUSIONS

Soft tissue tension could be reduced by previous closed reduction, and redislocation would not carry a greater risk of osteonecrosis in the subsequent open reduction.

Is Age or Surgical Approach Associated With Osteonecrosis in Patients With Developmental Dysplasia of the Hip? A Meta-analysis

BACKGROUND

Osteonecrosis of the femoral head is a major complication that negatively impacts the clinical and radiographic long-term outcome after treatment of developmental hip dysplasia (DDH). There are conflicting results in the literature whether age at the time of closed or open reduction and a specific surgical approach are associated with osteonecrosis. Better understanding of the impact of age at reduction and surgical approach is important to reduce the risk of osteonecrosis in patients with DDH.

QUESTIONS/PURPOSES

We aimed to evaluate the association between occurrence of osteonecrosis and (1) age at closed reduction; (2) age at open reduction; and (3) medial versus anterior operative approaches.

METHODS

A systematic review identified studies reporting osteonecrosis occurrence after treatment of DDH and at least 2 years of followup. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Methodologic quality was assessed using the methodologic index for nonrandomized studies. Generalized logistic models were used to estimate pooled odds ratios (ORs) in the meta-analysis. Sixty-six studies were included in the systematic review and 24 in the meta-analysis. Data on 481 hips treated by closed reduction and 584 hips treated by open reduction were available to evaluate the association between osteonecrosis and age. The association between osteonecrosis and operative approach was assessed using data on 364 hips treated by medial open reduction and 220 hips treated by anterior open reduction.

RESULTS

Age at reduction (> 12 months versus ≤ 12 months) was not associated with osteonecrosis after closed reduction (OR, 1.1; 95% confidence interval [CI], 0.4-3.2; p = 0.9) or open reduction (OR, 1.1; 95% CI, 0.7-1.9; p = 0.66). The overall, adjusted incidence of osteonecrosis (≥ Grade II) was 8.0% (95% CI, 2.8%-20.6%) among patients treated with closed reduction at or before 12 months of age and 8.4% (95% CI, 3.0%-21.5%) among those treated after 12 months. Similarly, the odds of osteonecrosis after open reduction did not differ between patients treated after the age of 12 months compared with those treated at or before 12 months (OR, 1.1; 95% CI, 0.7-1.9; p = 0.7). The incidence of osteonecrosis (≥ Grade II) was 18.3% (95% CI, 11.7%-27.4%) among patients who had index open reduction at or before 12 months of age and 20.0% (95% CI, 13.1%-29.4%) among those who had index open reduction after 12 months of age. Among hips treated with open reductions, there was no difference in osteonecrosis after medial versus anterior approaches (18.7% medial versus 19.6% anterior; OR, 1.1; 95% CI, 0.5-2.2; p = 0.9). Conclusions We did not find an association between closed or open reduction performed at or before 12 months of age and an increased risk of osteonecrosis of the femoral head. Delayed treatment past 1 year of age as a strategy to reduce the development of osteonecrosis was not supported by this meta-analysis. Open reduction through a medial or anterior approach may be recommended based on surgeon's preference, because we found no association between development of osteonecrosis and the type of surgical approach. However, many of the studies in the current literature are nonrandomized Level III or IV observational studies of inconsistent quality. Higher quality evidence is needed to better understand the effects of age at reduction and operative approach on the development of osteonecrosis after DDH treatment.

LEVEL OF EVIDENCE

Level III, therapeutic study.

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.

Ultrasound-guided gradual reduction using flexion and abduction continuous traction for developmental dysplasia of the hip: a new method of treatment

We describe our experience in the reduction of dislocation of the hip secondary to developmental dysplasia using ultrasound-guided gradual reduction using flexion and abduction continuous traction (FACT-R). During a period of 13 years we treated 208 Suzuki type B or C complete dislocations of the hip in 202 children with a mean age of four months (0 to 11). The mean follow-up was 9.1 years (five to 16). The rate of reduction was 99.0%. There were no recurrent dislocations, and the rate of avascular necrosis of the femoral head was 1.0%. The rate of secondary surgery for residual acetabular dysplasia was 19.2%, and this was significantly higher in those children in whom the initial treatment was delayed or if other previous treatments had failed (p = 0.00045). The duration of FACT-R was significantly longer in severe dislocations (p = 0.001) or if previous treatments had failed (p = 0.018). This new method of treatment is effective and safe in these difficult cases and offers outcomes comparable to or better than those of standard methods.

Failed Pavlik harness treatment for DDH as a risk factor for avascular necrosis

BACKGROUND

Avascular necrosis (AVN) of the femoral head is an irreversible complication seen in the treatment of developmental dysplasia of hip (DDH) with the Pavlik harness. Its incidence is reported to be low after successful reduction of the hip but high if the hip is not concentrically relocated. We aim to investigate its incidence after failed Pavlik harness treatment.

METHODS

We prospectively followed up a group of children who failed Pavlik harness treatment for DDH treated at our institution by the senior author between 1988 and 2001 and compared their rates of AVN with a group of children who presented late and hence were treated surgically. AVN was graded as described by Kalamchi and MacEwen and only grade 2 to 4 AVN was considered significant and included in the analysis.

RESULTS

Thirty-seven hips were included in the failed Pavlik group (group 1) and 86 hips in the no Pavlik group (group 2). Ten hips in group 1 developed AVN (27%), whereas only 7 hips in group 2 (8%) developed AVN; the odds of developing AVN after failed Pavlik treatment was 4.7 (95% confidence interval, 1.3-14.1) (P=0.009) with a relative risk of 3.32 (range, 1.37 to 8.05).

CONCLUSIONS

There was no statistically significant association observed with duration of splintage and severity of AVN (Spearman's correlation, -0.46; P=0.18). However, there was a positive correlation noted with age at presentation and severity of AVN. Therefore, we advise close monitoring of hips in the Pavlik harness and discontinue its use if the hips are not reduced within 3 weeks.

LEVEL OF EVIDENCE

Level III.

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.

Operative treatment and avascular necrosis of the hip development disorder

PURPOSE

The purpose of this research was (1) to evaluate the consequences of an operative treatment of hip developmental disorder in children, (2) to evaluate the significance of hip vascular supply in children through indirect radiological signs, such as morphological changes on femoral head, and to classify them with standard classification methods, and (3) to analyse the research results and make a recommendation for the following treatment dilemma: when is the optimal time for an operative treatment of a hip development disorder?

METHODS

The research is a retrospective and observational analysis based on the classification of indirect radiological signs of local vascular disorder by the Bucholz-Ogden's scale. Materials used for this research are medical records of treated patients at the Clinic for Orthopaedics and Traumatology of the Sarajevo University Clinical Centre. Using a random selection, two groups of 30 patients with hip development disorder were formed. The first group was comprised of patients aged six to 18 months and the second group of patients aged 18-60 months. The medical records used for this research included all necessary anamnestic details and postoperative state treatments with clinical findings and regular radiological check-up findings that include the presence or absence of the ossification nucleus as well as its position. All patients underwent surgery with the same operative technique. Data analysis points include the state at the beginning of the treatment, the postoperative state, the state at discharge as well as control findings that followed the development of the proximal femoral part up to 72 months on average. The analysis covered data such as age, sex, family anamnestic data, clinical findings and radiological findings regarding the femoral head morphology (appearance, size, shape, position and indirect signs showing lack of vascular supply). In addition, data analysis included the types of any previous conservative or operative treatments, the duration of previous conservative treatments and repeated hospitalization.

RESULTS

In group 1, 86.6 % were female patients and 80 % in group 2. Family history was positive in 15.6 % in group 1 and 13.3 % in group 2. A total of 51.6 % of all patients started walking on time, while the rest had problems with verticalization. Of all patients, 47 % did not undergo any kind of prior treatment. Only 62.2 % of group 1 patients had ossification nucleus present, while the entire group 2 had it present. Results showed that 24.32 % of group 1 patients had none or minimal signs of avascular necrosis (AVN) while 39.47 % of group 2 had none or minimal signs of AVN; 60.52 % of group 2 patients had signs of AVN.

CONCLUSION

The results of this study show that the performance of a surgical treatment during the age between 12 and 20 months is burdened by the highest percentage of avascular necrosis. Even though AVN can be noticed in other age groups, according to the results of our research, it seems that vascular supply of the hip is the most vulnerable in the period between 12 and 20 months.

Idiopathic hypertonicity as a cause of stiffness after surgery for developmental dysplasia of the hip

INTRODUCTION

There are various complications reported with surgical treatment of DDH. Most studied complication is avascular necrosis of the femoral head and hip stiffness. The purpose of this report was to describe a case with severe stiffness of the hip due to hypertonicity in periarticular muscles after it was treated for developmental dysplasia of the hip (DDH).

PRESENTATION OF CASE

Three-year-old patient referred to our institution with bilateral DDH. Two hips were operated separately in one year with anterior open reduction, femoral shortening osteotomy. Third month after last surgery, limited right hip range of motion and limb length discrepency identified. Clinical examination revealed that patient had limited range of motion (ROM) in the right hip and compensated this with pelvis obliquity. Gluteus medius, sartorius and iliofemoral band release performed after examination under general anesthesia. Symptoms were persisted at 3rd week control and examination of the patient in general anesthesia revealed full ROM without increased tension. For the identified hypertonicity, ultrasound guided 100IU botulinum toxin A injection performed to abductor group and iliopsoas muscles. Fifth month later, no flexor or abductor tension observed, and there was no pelvic obliquity.

DISCUSSION

Stiffness as a complication is rare and is usually resolved without treatment or simple physical therapy. Usually it is related with immobilization or surgery associated joint contracture, and spontaneous recovery reported. Presented case is diagnosed as hip stiffness due to underlying local hypertonicity. That is resolved with anesthesia and it was treated after using botulinum toxin A injection.

CONCLUSION

Hypertonicity with hip stiffness after surgical treatment of DDH differ from spontaneous recovering hip range of motion limitation and treatment can only be achieved by reduction of the muscle hypertonicity by neuromuscular junction blockage.

Treatment of developmental dislocation of hip: does changing the hip abduction angle in the hip spica affect the rate of avascular necrosis of the femoral head?

Avascular necrosis (AVN) of the femoral head is a serious complication in the management of developmental dislocation of the hip. Increasing the abduction angle increases its stability but compromises the vascularity of the femoral head. From our database of 240 children treated for developmental dislocation of hip by the two senior authors between 1998 and 2008, we defined two groups of children who underwent closed or medial open reduction of the hip after a failed Pavlik treatment or if patients presented late. In group 1, the reduced hip was immobilized in around 90° flexion, 60° abduction, and 0-10° internal rotation. In group 2 the hip was immobilized in around 45° of hip abduction with flexion and internal rotation as before. The first and second authors independently analysed these two groups blinded to the hip abduction angle. Our hypothesis was that a reduction in the hip abduction angle would reduce the incidence of AVN in the second group without compromising the stability. All eligible children were included, and there were 42 children in group 1 and 44 children in group 2. An almost equal number of children underwent closed and medial open reduction in both the groups. The age at reduction was a mode of 6 months (range 6-13 months) and 7 months (range 7-12 months), respectively. The abduction angle in the first group had a mode of 60° (range 52-70°) and the second group had a mode of 45° (range 38-50°). Radiographic evidence of AVN as described by Salter and colleagues was seen in eight children (19%) in the first group and seven children (16%) in the second group (P=0.78). Redislocation occurred in one child in the second group and none in the first group. In summary, the results show a nonsignificant reduction in the incidence of AVN when the hip abduction angle was reduced with no significant increased risk of redislocation.

Predictive values for the severity of avascular necrosis from the initial evaluation in closed reduction of developmental dysplasia of the hip

The severity of avascular necrosis (AVN) after closed reduction of developmental dysplasia of the hip determines the final clinical outcomes. Our study aimed to correlate the possible predictors with the severity of AVN. After follow-up of the patients on skeletal maturity, 37 patients (39 hips) were included. Age at reduction is important to predict the severity of AVN. Older patients are at a greater risk of suffering from more severe AVN. Other values such as the degree of initial dislocation or the impact of the femoral head ossific nucleus show no precognition to the severity of AVN.

Delayed diagnosis of developmental dislocation of the hip: the Western Australian experience

BACKGROUND

A delay in the diagnosis of developmental dislocation of the hip has many long-term consequences. This retrospective study was undertaken in order to establish an incidence of late-presenting developmental dislocation of the hip in Western Australia, and investigate possible causes for missed diagnoses.

METHOD

Data were collected retrospectively from 1 January to 31 December 2010. Theatre records were searched for operative descriptions including the words 'arthrogram hip', 'EUA hip', 'closed reduction hip', 'open reduction hip' and 'spica'. Medical records were checked to establish the demographic details and background history of cases identified. Delayed diagnosis of developmental dysplasia of the hip (DDH) was defined as a dislocated hip requiring operative reduction, diagnosed at age greater than 3 months.

RESULTS

Seventeen children with 21 dislocated hips were identified. Age at diagnosis ranged from 6 months to 5 years. Girls accounted for 88.2% (15/17) and the left hip was involved two-thirds of the time (14/21). Bilateral dislocations were found in four children.

CONCLUSION

This study has identified an incidence of late-presenting developmental hip dislocation of approximately three times the previously established rate. Possible reasons for this are explored. Additional retrospective audit is now underway, and changes are already in place to ensure that infants with DDH born in Western Australia are identified and treated as early as possible.

Arthroscopic reduction of the dislocated hip in infants

We present our early experience of arthroscopic reduction of the dislocated hip in very young infants with developmental dysplasia of the hip (DDH).

Eight dislocated hips, which had failed attempts at closed reduction, were treated by arthroscopy of the hip in five children with a mean age of 5.8 months (4 to 7). A two-portal technique was used, with a medial sub-adductor portal for a 2.7 mm cannulated system with a 70° arthroscope and an anterolateral portal for the instruments. Following evaluation of the key intra-articular structures, the hypertrophic ligamentum teres and acetabular pulvinar were resected, and a limited release of the capsule was performed prior to reduction of the hip. All hips were reduced by a single arthroscopic procedure, the reduction being confirmed on MRI scan. None of the hips had an inverted labrum. The greatest obstacle to reduction was a constriction of the capsule. At a mean follow-up of 13.2 months (9 to 24), all eight hips remained stable. Three developed avascular necrosis. The mean acetabular index decreased from 35.5° (30° to 40°) pre-operatively to 23.3° (17° to 28°).

This study demonstrates that arthroscopic reduction is feasible using two standardised portals. Longer follow-up studies are necessary to evaluate the functional results.

Late diagnosis of developmental dysplasia of the hip: an analysis of risk factors

A neonatal clinical screening program for developmental dysplasia of the hip (DDH) operates in South Australia to diagnose DDH as early as possible. However, some cases of DDH are diagnosed late (>3 months of age). The aims of this study were to identify the specific risk factors for late diagnosis by comparing early diagnosed DDH, late diagnosed DDH, and normal controls in the South Australian population. There were 1945 children with DDH born between 1988 and 2003, of which 67 cases were late diagnosis (3.4%). Maternal characteristics, pregnancy, and delivery details were analyzed, and compared with controls (early diagnosed DDH and the general population). There was a trimodal pattern of age at presentation with a gradual increase in the incidence of late diagnosed DDH over the time period in this study. Birthweight (<2500 g), birth in a rural setting, and early hospital discharge following delivery (<4 days) were significant risk factors for late diagnosed DDH. Breech presentation and delivery by caesarean section were protective for late diagnosed DDH. Risk factors for late diagnosed DDH relate to factors that influence the screening program. A rigorous population-based hip surveillance program is important for early diagnosis of DDH.

Screening the newborn for developmental dysplasia of the hip: now what do we do?

The Pediatric Orthopaedic Society of North America recommends that all health care providers who are involved in the care of infants continue to follow the clinical practice guideline for early detection of developmental hip dysplasia (DDH) outlined by the American Academy of Pediatrics. Although evaluation of children with risk factors for DDH is important, most DDH occurs in infants who have no risk factors. For all infants, a competent newborn physical examination using the Ortolani maneuver is the most useful procedure to detect hip instability. Early treatment of an unstable hip with a Pavlik harness or similarly effective orthosis is effective, safe, and strongly advised. Despite having had normal newborn and infant hip examinations, there remains the possibility of a late-onset hip dislocation needing treatment in approximately 1 in 5000 infants.