Staged weaning versus immediate cessation of Pavlik harness treatment for developmental dysplasia of the hip

Resolving residual acetabular dysplasia following successful brace treatment for developmental dysplasia of the hip in infants

Aims

Radiological residual acetabular dysplasia (RAD) has been reported in up to 30% of children who had successful brace treatment of infant developmental dysplasia of the hip (DDH). Predicting those who will resolve and those who may need corrective surgery is important to optimize follow-up protocols. In this study we have aimed to identify the prevalence and predictors of RAD at two years and five years post-bracing.

Methods

This was a single-centre, prospective longitudinal cohort study of infants with DDH managed using a published, standardized Pavlik harness protocol between January 2012 and December 2016. RAD was measured at two years' mean follow-up using acetabular index-lateral edge (AI-L) and acetabular index-sourcil (AI-S), and at five years using AI-L, AI-S, centre-edge angle (CEA), and acetabular depth ratio (ADR). Each hip was classified based on published normative values for normal, borderline (1 to 2 standard deviations (SDs)), or dysplastic (> 2 SDs) based on sex, age, and laterality.

Results

Of 202 infants who completed the protocol, 181 (90%) had two and five years' follow-up radiographs. At two years, in 304 initially pathological hips, the prevalence of RAD (dysplastic) was 10% and RAD (borderline) was 30%. At five years, RAD (dysplastic) decreased to 1% to 3% and RAD (borderline) decreased to < 1% to 2%. On logistic regression, no variables were predictive of RAD at two years. Only AI-L at two years was predictive of RAD at five years (p < 0.001). If both hips were normal at two years' follow-up (n = 96), all remained normal at five years. In those with bilateral borderline hips at two years (n = 21), only two were borderline at five years, none were dysplastic. In those with either borderline-dysplastic or bilateral dysplasia at two years (n = 26), three (12%) were dysplastic at five years.

Conclusion

The majority of patients with RAD at two years post-brace treatment, spontaneously resolved by five years. Therefore, children with normal radiographs at two years post-brace treatment can be discharged. Targeted follow-up for those with abnormal AI-L at two years will identify the few who may benefit from surgical correction at five years' follow-up.

Prognostic factors for failed Pavlik harness treatment in infants with developmental dysplasia of the hip: a retrospective cohort study

PURPOSE

Pavlik harness treatment is the most common treatment in newborns diagnosed with developmental dysplasia of the hip (DDH). The success rates and predictors for failure have been debated over the last decade. In this study, we explored our treatment failure rate and potential prognostic factors that could predict the failure of Pavlik harness (PH) treatment in patients with DDH.

METHODS

Two hundred and sixty-five patients were treated with PH based on the Graf hip types of classification. Age, gender, first born status, family history, foot deformity, plagiocephaly, breech presentation, hip abduction, hip stability, Graf hip type, Galeazzi sign, bilateralism, and femoral nerve palsy were tested as predictors for failure in multivariate logistic regression mode. Success and failure were determined by the normalization of the hip based on the Graf hip classification.

RESULTS

The failure rate of patients treated with Pavlik harness was 16.6% which is within the reported range of failure rate. The mean age of patients who were successfully treated was 6.73 weeks in comparison to 8.84 weeks for those who failed. Age, plagiocephaly, hip instability, Graf classification, and the development of femoral nerve palsy were found to be predictors for failure of PH treatment upon univariate analysis only. However, only the presence of Galeazzi sign, hip instability, high grades of Graf hip classification, and the development of femoral nerve palsy proved to be independent predictors for failed PH treatment upon multivariate logistic regression analysis.

CONCLUSIONS

Pavlik harness treatment is a successful treatment with an average success of 83.4%. Several independent predictors for failure of PH treatment have been identified. These include a positive Galeazzi sign, a frankly dislocated hip, Graf types III and IV, and the development of femoral nerve palsy.

A comprehensive nonoperative treatment protocol for developmental dysplasia of the hip in infants

Aims

Brace treatment is the cornerstone of managing developmental dysplasia of the hip (DDH), yet there is a lack of evidence-based treatment protocols, which results in wide variations in practice. To resolve this, we have developed a comprehensive nonoperative treatment protocol conforming to published consensus principles, with well-defined a priori criteria for inclusion and successful treatment.

Methods

This was a single-centre, prospective, longitudinal cohort study of a consecutive series of infants with ultrasound-confirmed DDH who underwent a comprehensive nonoperative brace management protocol in a unified multidisciplinary clinic between January 2012 and December 2016 with five-year follow-up radiographs. The radiological outcomes were acetabular index-lateral edge (AI-L), acetabular index-sourcil (AI-S), centre-edge angle (CEA), acetabular depth ratio (ADR), International Hip Dysplasia Institute (IHDI) grade, and evidence of avascular necrosis (AVN). At five years, each hip was classified as normal (< 1 SD), borderline dysplastic (1 to 2 SDs), or dysplastic (> 2 SDs) based on validated radiological norm-referenced values.

Results

Of 993 infants assessed clinically and sonographically, 21% (212 infants, 354 abnormal hips) had DDH and were included. Of these, 95% (202 infants, 335 hips) successfully completed bracing, and 5% (ten infants, 19 hips) failed bracing due to irreducible hip(s). The success rate of bracing for unilateral dislocations was 88% (45/51 infants) and for bilateral dislocations 83% (20/24 infants). The femoral nerve palsy rate was 1% (2/212 infants). At five-year follow-up (mean 63 months (SD 5.9; 49 to 83)) the prevalence of residual dysplasia after successful brace treatment was 1.6% (5/312 hips). All hips were IHDI grade I and none had AVN. Four children (4/186; 2%) subsequently underwent surgery for residual dysplasia.

Conclusion

Our comprehensive protocol for nonoperative treatment of infant DDH has shown high rates of success and extremely low rates of residual dysplasia at a mean age of five years.

Implementing the AAOS Guidelines for Screening of Developmental Dysplasia of the Hip Before the Age of 6 Months in Taiwan

BACKGROUND

The prevalence of developmental dysplasia of the hip (DDH) has been considered to be low in East Asia, but this may be incorrect because of inconsistent diagnostic definitions and testing criteria. In 2015, the AAOS released guidelines for systematic screening for DDH in newborns. We implemented these guidelines and compared DDH incidence and outcomes before and after their implementation.

METHODS

We used a historic comparison cohort of newborns with DDH between July 2015 and May 2017 before guideline implementation (the preguideline group); their data were retrieved using electronic medical records. In this group, the newborns received general hip screening without systemic follow-up. The postguideline group included newborns who were screened for hip dysplasia and followed up per the AAOS guidelines between July 2017 and May 2019. Their data were prospectively collected. The primary outcome in the postguideline group was DDH incidence. Other outcomes included rates of referral, surgery, and complications, and DDH prognosis.

RESULTS

The preguideline and postguideline groups included 3534 and 2663 newborns, respectively, of whom 49 (1.1%) and 225 (8.4%), respectively, were referred to the pediatric orthopaedic clinic enrolled. In the postguideline group, 35 patients were diagnosed as having DDH (incidence: 1.3%, 95% CI: 0.8%-1.9%). Both the incidence and referral rates were significantly higher in the postguideline group than in the preguideline group. Furthermore, the mean age at referral was 6.7±10.06 months and 0.9±0.25 months in the preguideline and postguideline groups, respectively, indicating a potential for early treatment in the postguideline group. Finally, the female sex was identified as a risk factor for residual hip dysplasia at 6 months of age.

CONCLUSION

DDH incidence in East Asia seems comparable to that in Western countries. Implementing the AAOS guidelines increased the diagnosis rate and opportunity for early treatment initiation, thus potentially avoiding surgical intervention. Nevertheless, residual DDH may be detected in some patients at 6 months of age, particularly in female infants.

LEVEL OF EVIDENCE

Level IV.

Splinting for the non-operative management of developmental dysplasia of the hip (DDH) in children under six months of age

BACKGROUND

Developmental dysplasia of the hip (DDH) describes the abnormal development of a hip in childhood, ranging from complete dislocation of the hip joint to subtle immaturity of a hip that is enlocated and stable within the socket. DDH occurs in around 10 per 1000 live births, though only one per 1000 are completely dislocated. There is variation in treatment pathways for DDH, which differs between hospitals and even between clinicians within the same hospital. The variation is related to the severity of dysplasia that is believed to require treatment, and the techniques used to treat dysplasia.

OBJECTIVES

To determine the effectiveness of splinting and the optimal treatment strategy for the non-operative management of DDH in babies under six months of age.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, seven other electronic databases, and two trials registers up to November 2021. We also checked reference lists, contacted study authors, and handsearched relevant meetings abstracts.

SELECTION CRITERIA

Randomised controlled trials (RCTs), including quasi-RCTs, as well as non-RCTs and cohort studies conducted after 1980 were included. Participants were babies with all severities of DDH who were under six months of age. Interventions included dynamic splints, static splints or double nappies (diapers), compared to no splinting or delayed splinting.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, extracted data and performed risk of bias and GRADE assessments. The primary outcomes were: measurement of acetabular index at years one, two and five, as determined by radiographs (angle): the need for operative intervention to achieve reduction and to address dysplasia; and complications. We also investigated other outcomes highlighted by parents as important, including the bond between parent and child and the ability of mothers to breastfeed.

MAIN RESULTS

We included six RCTs or quasi-RCTs (576 babies). These were supported by 16 non-RCTs (8237 babies). Five studies had non-commercial funding, three studies stated 'no funding' and 14 studies did not state funding source. The RCTs were generally at unclear risk of bias, although we judged three RCTs to be at high risk of bias for incomplete outcome data. The non-RCTs were of moderate and critical risk of bias. We did not undertake meta-analysis due to methodological and clinical differences between studies; instead, we have summarised the results narratively. Dynamic splinting versus delayed or no splinting Four RCTs and nine non-RCTs compared immediate dynamic splinting and delayed dynamic splinting or no splinting. Of the RCTs, two considered stable hips and one considered unstable (dislocatable) hips and one jointly considered unstable and stable hips. No studies considered only dislocated hips. Two RCTs (265 babies, very low-certainty evidence) reported acetabular index at one year amongst stable or dislocatable hips. Both studies found there may be no evidence of a difference in splinting stable hips at first diagnosis compared to a strategy of active surveillance: one reported a mean difference (MD) of 0.10 (95% confidence interval (CI) -0.74 to 0.94), and the other an MD of 0.20 (95% CI -1.65 to 2.05). Two RCTs of stable hips (181 babies, very low-certainty evidence) reported there may be no evidence of a difference between groups for acetabular index at two years: one study reported an MD of -1.90 (95% CI -4.76 to 0.96), and another study reported an MD of -0.10 (95% CI -1.93 to 1.73), but did not take into account hips from the same child. No study reported data at five years. Four RCTs (434 babies, very low-certainty evidence) reported the need for surgical intervention. Three studies reported that no surgical interventions occurred. In the remaining study, two babies in the dynamic splinting group developed instability and were subsequently treated surgically. This study did not explicitly state if this treatment was to achieve concentric reduction or address residual dysplasia. Three RCTs (390 babies, very low-certainty evidence) reported no complications (avascular necrosis and femoral nerve palsy). Dynamic splinting versus static splinting One RCT and five non-RCTs compared dynamic versus static splinting. The RCT (118 hips) reported no occurrences of avascular necrosis (very low-certainty evidence) and did not report radiological outcomes or need for operative intervention. One quasi-RCT compared double nappies versus delayed or no splinting but reported no outcomes of interest. Other comparisons No RCTs compared static splinting versus delayed or no splinting or staged weaning versus immediate removal.

AUTHORS' CONCLUSIONS

There is a paucity of RCT evidence for splinting for the non-operative management of DDH: we included only six RCTs with 576 babies. Moreover, there was considerable heterogeneity between the studies, precluding meta-analysis. We judged the RCT evidence for all primary outcomes as being of very low certainty, meaning we are very uncertain about the true effects. Results from individual studies provide limited evidence of intervention effects on different severities of DDH. Amongst stable dysplastic hips, there was no evidence to suggest that treatment at any stage expedited the development of the acetabulum. For dislocatable hips, a delay in treatment onset to six weeks does not appear to result in any evidence of a difference in the development of the acetabulum at one year or increased risk of surgery. However, delayed splinting may reduce the number of babies requiring treatment with a harness. No RCTs compared static splinting with delayed or no splinting, staged weaning versus immediate removal or double nappies versus delayed or no splinting. There were few operative interventions or complications amongst the RCTs and the non-randomised studies. There's no apparent signal to indicate a higher frequency of either outcome in either intervention group. Given the frequency of this disease, and the fact that many countries undertake mandatory DDH screening, there is a clear need to develop an evidence-based pathway for treatment. Particular uncertainties requiring future research are the effectiveness of splinting amongst stable dysplastic hips, the optimal timing for the onset of splinting, the optimal type of splint to use and the need for 'weaning of splints'. Only once a robust pathway for treatment is established, can we properly assess the cost-effectiveness of screening interventions for DDH.

Treatment of centered developmental dysplasia of the hip under the age of 1 year: an evidence-based clinical practice guideline

Despite the high incidence of developmental dysplasia of the hip (DDH), treatment is very diverse. Therefore, the Dutch Orthopedic Society developed a clinical practice guideline with recommendations for optimal and uniform treatment of DDH. This article summarizes the guideline on centered DDH (i.e. Graf types 2A–C).

The guideline development followed the criteria of Appraisal of Guidelines for Research and Evaluation II. A systematic literature review was performed to identify randomized controlled trials and comparative cohort studies including children <1 year with centered DDH. Articles were included that compared (1) treatment with observation, (2) different abduction devices, (3) follow-up frequencies, and (4) discontinuation methods. Recommendations were based on Grading Recommendations Assessment, Development, and Evaluation, which included the literature, clinical experience and consensus, patient and parent comfort, and costs.

Out of 430 potentially relevant articles, 5 comparative studies were included. Final guideline recommendations were (1) initially observe 3-month-old patients with centered DDH, start abduction treatment if the hip does not normalize after 6–12 weeks; (2) prescribe a Pavlik harness to children <6 months with persisting DDH on repeated ultrasonography, consider alternative abduction devices for children >6 months; (3) assess patients every 6 weeks; and (4) discontinue the abduction device when the hip has normalized or when the child is 12 months.

This paper presents a summary of part 1 of the first evidence-based guideline for treatment of centered DDH in children <1 year. Part 2 presents the guideline on decentered DDH in a separate article.

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.

Exploring infant hip position and muscle activity in common baby gear and orthopedic devices

Infant positioning in daily life may affect hip development. While neonatal animal studies indicate detrimental relationships between inactive lower extremities and hip development and dysplasia, no research has explored infant hip biomechanics experimentally. This study evaluated hip joint position and lower extremity muscle activity of healthy infants in common body positions, baby gear, and orthopedic devices used to treat hip dysplasia (the Pavlik harness and the Rhino cruiserabduction brace). Surface electromyography(EMG) and marker-based motion capture recorded lower extremity muscle activity and kinematics of 22 healthy full-term infants (4.2±1.6 months, 13M/9F) during five conditions: Pavlik harness, Rhino brace, inward-facing soft-structured baby carrier, held in arms facing inwards, and a standard car seat. Mean filtered EMG signal, time when muscles were active, and hip position (angles) were calculated. Compared to the Pavlik harness, infants exhibited similar adductor activity (but lower hamstring and gluteus maximus activity) in the Rhino abduction brace, similar adductor and gluteus maximus activity (but lower quadriceps and hamstring activity) in the baby carrier, similar but highly variable muscle activity in-arms, and significantly lower muscle activity in the car seat. Hip position was similar between the baby carrier and the Pavlik harness. This novel infant biomechanics study illustrates the potential benefits of using inward-facing soft-structured baby carriers for healthy hip development and highlights the potential negative impact of using supine-lying container-type devices such as car seats for prolonged periods of time. Further study is needed to understand the full picture of how body position impacts infant musculoskeletal development.

Evidence based treatment for developmental dysplasia of the hip in children under 6 months of age. Systematic review and exploratory analysis

INTRODUCTION

Developmental dysplasia of the hip (DDH) is a common paediatric orthopaedic condition that attracts a substantive amount of controversy. The treatments vary because of the wide spectrum of the condition and the age of children at presentation. Although conservative and surgical treatments exist; it is widely accepted that conservative treatment is the first line of treatment in the first 6 months of life. Several devices have been proposed as the treatment of choice; however, to the best of our knowledge these have not been critically appraised. Therefore, we conducted this review.

METHODS

A modified Cochrane method was followed with a preplanned detailed research protocol that was developed to guide all aspects of the review. Treatment failure of the devices was chosen as the primary outcome. Secondary outcomes included femoral nerve palsy (FNP), avascular necrosis of the femoral head (AVN), residual dysplasia, skin problems, failure of subsequent surgical treatment, compliance and tolerance issues. Results are reported according to the PRISMA guidelines.

RESULTS

A total of 30 studies were included in the review comparing 5 devices (The Pavlik harness, the Von Rosen splint, the Tubingen brace, the Frejka pillow, and the Aberdeen splint). The devices were compared in terms of success rate, AVN rate and residual dysplasia. The von Rosen splint has been shown to be superior to other devices in term of success rates and residual dysplasia (Χ2: P < 0.05).

CONCLUSION

The review findings should be interpreted with caution as there are substantive flaws in the literature and a randomized control trail is warranted to confirm the best device to treat DDH. This is feasible given the magnitude of the problem, the clear diagnostic criteria and the treatment options.

Is There a Benefit to Weaning Pavlik Harness Treatment in Infantile DDH?

BACKGROUND

Following successful treatment of developmental hip dysplasia with a Pavlik harness, controversy exists over the benefit of continued harness use for an additional "weaning" period beyond ultrasonographic normalization versus simply terminating treatment. Although practitioners are often dogmatic in their beliefs, there is little literature to support the superiority of 1 protocol over the other. The purpose of this study was to compare the radiographic outcomes of 2 cohorts of infants with developmental hip dysplasia treated with Pavlik harness, 1 with a weaning protocol and 1 without.

METHODS

This was a comparative review of patients with dislocated/reducible hips and stable dysplasia from 2 centers. All patients had pretreatment ultrasounds, and all started harness treatment before 3 months of age. On the basis of power analysis, a sufficient cohort of hips were matched based on clinical examination, age at initiation, initial α angle, and initial percent femoral head coverage. Patients from institution W (weaned) were weaned following ultrasonographic normalization, whereas those from institution NW (not weaned) immediately ceased treatment. The primary outcome was the acetabular index at 1 year of age.

RESULTS

In total, 16 dislocated/reducible and 16 stable dysplastic hips were matched at each center (64 total hips in 53 patients). Initial α angle and initial femoral head coverage were not different between cohorts for either stable dysplasia (P=0.59, 0.81) or dislocated/reducible hips (P=0.67, 0.70), respectively. As expected, weaned hips were treated for significantly longer in both the stable dysplasia (1540.4 vs. 1066.3 h, P<0.01), and dislocated/reducible cohorts (1596.6 vs. 1362.5 h, P=0.01). Despite this, we found no significant difference in the acetabular index at 1 year in either cohort (22.8 vs. 23.1 degrees, P=0.84 for stable dysplasia; 23.9 vs. 24.8 degrees, P=0.32 for Ortolani positive).

CONCLUSIONS

Despite greater total harness time, infants treated with additional Pavlik weaning did not demonstrate significantly different radiographic results at 1 year of age compared with those who were not weaned. However, differences in follow-up protocols between centers support the need for a more rigorous randomized controlled trial.

LEVEL OF EVIDENCE

Level III.

The treatment of neonatal hip dysplasia with splints in the United Kingdom: time for consensus?

PURPOSE

To understand the variation in the management of hip dysplasia identified from the United Kingdom neonatal selective screening programme.

METHODS

Having been designed and tested by the research committee of the British Society for Children's Orthopaedic Surgery (BSCOS), a nationwide online survey was conducted of BSCOS members to ascertain their treatment strategies for neonatal hip dysplasia.

RESULTS

There were 111 responses (60% of members), which illustrated wide variation in care. In all, 91 (over 80%) of respondents treat more than ten cases per year, yet only 61 (55%) work to an agreed protocol. A total of 90 (81%) use the Graf classification and 103 (93%) use the Pavlik harness initially. Consensus is lacking in key areas including duration of harness use, hours per day, clothing and weaning. Importantly, notable differences of opinion even exist regarding which hip pathologies need treatment.

CONCLUSION

This study quantifies the wide variation in many key elements of the initial treatment of neonatal hip dysplasia in the United Kingdom. This variation appears unnecessary and unacceptable as the Getting It Right First Time programme seeks to standardize care pathways. The charitable sector has called for consensus to mitigate parental anxiety, and it has been suggested that this could allow better integration of hip dysplasia into national screening pathways. Standardized care benefits patients and represents the platform from which we can begin understanding effectiveness and optimizing outcomes.

LEVEL OF EVIDENCE

Level V.

Late acetabular dysplasia after successful treatment for developmental dysplasia of the hip using the Pavlik method: A systematic literature review

The Pavlik method is the most common method used for treatment of developmental dysplasia of the hip (DDH). Late acetabular dysplasia despite successful treatment, however, has had varied reporting. A systematic review was performed, investigating the long-term outcomes of DDH treated with the Pavlik method. Seventeen studies met inclusionary criteria, including 6029 hips treated with an average of 5.29 years follow-up. Radiographic evidence of late dysplasia was present in 280 hips, with 109 hips requiring additional surgery. A specified treatment algorithm had significantly decreased rates of radiographic dysplasia (3.8% vs 17.6%, p = 0.004).

Level of evidence

IV.

Hip Mobilization at Preterm Age May Accelerate Developmental Dysplasia Recovery

PURPOSE

Few studies have described mobilization approaches in developmental dysplasia of the hip (DDH). The present study describes the hip mobilization of a preterm infant (born at 33 6/7 weeks of gestational age) diagnosed with DDH.

DESIGN AND METHODS

During the 43-day hospital stay, the infant was seen twice a week (ten sessions, 20 minutes each). All sessions included hip approximation maneuvers, with the hip positioned in abduction, lateral rotation and flexion, and lower limbs passive mobilization, which were taught to the mother. Early intervention with auditory, tactile, visual, and vestibular stimulations was also performed. The infant was assessed with hip ultrasound before and after treatment.

RESULTS

At 34 2/7 weeks of gestational age, she was classified as Graf IIa (left: alpha: 55°, beta: 68°; right: alpha: 59°, beta: 64°). At 40 5/7 weeks, she was classified as Graf I for left (alpha: 67°; beta: 42°) and right (alpha: 66°; beta: 42°) hips.

PRACTICAL IMPLICATIONS

The intervention seemed to accelerate the acquisition of stability of dysplasic hips in a preterm infant. The outcome supports further investigation of hip approximation maneuvers as part of early stimulation in preterm infants with DDH during hospital stay.

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.

Success of Pavlik Harness Treatment Decreases in Patients ≥ 4 Months and in Ultrasonographically Dislocated Hips in Developmental Dysplasia of the Hip

BACKGROUND

Treatment of developmental dysplasia of the hip (DDH) using the Pavlik harness has been a widely used method in patients between 0 and 6 months of age for many years. However, the factors influencing the success rate of this treatment modality have still not exactly been determined as a result of the limited number of clinical studies with higher level of evidence.

QUESTIONS/PURPOSES

We, therefore, asked whether (1) patient-related variables such as age, gender, and laterality; coexisting risk factors including family history, breech presentation, intrauterine packing, first-born girl, oligohydroamnios, and swaddling; and (2) the severity of hip dysplasia, defined by ultrasonography, are associated with differences in the success rate of Pavlik harness treatment in infants with DDH.

METHODS

Between 2012 and 2014, we treated 153 children (≤ 6 months of age) with DDH using the Pavlik harness. Hip dysplasia apart from coexisting neuromuscular disorders, congenital abnormalities, or syndromes was our inclusion criteria. Of patients thus treated, 130 (85%) were available for the evaluation of patient- and hip-related variables against the success of Pavlik harness treatment. Mean age of these patients on day of diagnosis and initiation of treatment was 108 days. The diagnostic and followup examinations of the hips were made by ultrasonography using Graf's method. Pavlik harness treatment was initiated in Graf Type IIa- and worse hips and treatment was considered "successful" when a Graf Type I hip was achieved. Pavlik harness treatment was successful in 92 (71%) patients (130 of 181 hips [72%]).

RESULTS

Age was the only patient-related variable influencing the success rate of the treatment; the mean age of children in whom Pavlik harness treatment succeeded (97 ± 38 days; 95% confidence interval [CI], 90-112) was lower than the age of those who failed (135 ± 37 days; 95% CI, 123-147; p < 0.001). The highest success rate was obtained in children younger than age 3 months (37 of 40 [93%]) and the lowest one older than age 5 months (nine of 24 [37%]) (p < 0.001). The threshold age value related to an increased risk of failure was found to be 4 months and older, which had a sensitivity of 66% and a specificity of 77% (p < 0.001). A higher initial α angle was observed in the hips in which the treatment succeeded (53° ± 6°; 95% CI, 51°-53°) than in those that failed (47° ± 7°; 95% CI, 45°-50°; p < 0.001). The threshold α angle value related to an increased risk of treatment failure was 46° and less, which had a sensitivity of 47% and a specificity of 86% (p < 0.001). Dislocated hips (Graf Type III and IV hips) had the lowest rate of treatment success (five of 19 [26%] and two of four [50%], respectively), whereas Graf Type IIa- hips had the highest (27 of 29 [93%]) (p < 0.001).

CONCLUSIONS

We conclude that Pavlik harness treatment is less effective in children at and over the age of 4 months at the time the harness is first applied as well as in hips with complete dislocations and hips with severely deficient acetabular bony roofs. In such older patients and worse hip types, the use of initial Pavlik harness treatment needs to be revisited. Future studies, comparing the outcomes of the Pavlik harness treatment and other types of interventions in such patients and hip types, are needed.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Developmental dysplasia of the hip in neonates: evolution of acetabular dysplasia after hip stabilization by brief Pavlik harness treatment

BACKGROUND

The recommended treatment duration in neonates with developmental dysplasia of the hip (DDH) varies depending on whether prolonged Pavlik harness therapy is believed to favourably affect the course of the acetabular dysplasia. According to one theory, several months of additional Pavlik harness therapy after achieving hip reduction contributes to correct the acetabular dysplasia. Another theory holds that hip dislocation induces the acetabular dysplasia, which corrects spontaneously once the femoral head is properly seated in the acetabulum. Here, we evaluated this second theory by studying outcomes after early brief Pavlik harness therapy.

HYPOTHESIS

Acetabular dysplasia associated with neonatal hip instability undergoes self-correction provided stable hip reduction is achieved very early after birth. Therefore, the duration of Pavlik harness therapy can be substantially shortened.

MATERIALS AND METHODS

We defined hip instability as either reducible hip dislocation or a very easily dislocatable hip with a soft clunk precluding determination of spontaneous hip position as dislocated or reduced. Static and dynamic ultrasound scans were obtained. Patients with ultrasonographic instability (pubo-femoral distance>5mm with less than 50% of coverage) underwent a second physical examination and received treatment. We re-evaluated 42 abnormal hips in 30 patients after a mean follow-up of 6.7 years (range, 5-14 years). Mean age at treatment initiation was 5 days (range, 1-15 days) and mean treatment duration was 34 days (range, 15-75 days).

RESULTS

Mean acetabular angle was 20° (range, 12°-30°) and mean Wiberg's lateral centre-edge angle was 30° (range, 22°-35°). Blunting of the lateral angle of the bony roof was noted in 8 hips at last follow-up. In 1 patient whose hip was stable clinically but unstable by ultrasonography at 21 days of age, recurrent dislocation occurred at 5 months of age. The Severin class was 1a in all patients.

DISCUSSION

Despite continuing controversy about whether hip dislocation induces dysplasia or vice versa, the need for early treatment is universally recognised. The optimal treatment duration, however, remains debated. Proponents of the familial determinism of DDH consider that acetabular shaping is genetically programmed when the femoral head is centred in the acetabular socket. Others advocate routine prolongation of Pavlik harness therapy for 2 months or longer, based on the opinion that this strategy decreases the dislocation recurrence rate and that mechanical hip unloading may promote correction of the dysplasia. Mean treatment duration in our population was 34 days and our sole objective was to treat the instability. The hip was reduced and held in its proper position long enough to allow sufficient capsule and ligament tightening to stabilise the hip. Under these conditions, the acetabular dysplasia underwent self-correction that was not related to treatment duration.

CONCLUSION

Very early Pavlik harness therapy to ensure rapid hip reduction and stabilisation optimises the potential of the acetabulum for spontaneous remodelling.

LEVEL OF EVIDENCE

Level IV, retrospective study.