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Because not all infants can be screened for DDH by experts, early diagnosis of developmental dysplasia of the hip (DDH) by primary health care professionals is important. We developed a broadband electroacoustic sound transmission-detection (sonospectrography) system and explored its utility in 22 patients (average age, 5.9 years; range, 0.3–14 years) with unilateral DDH in this preliminary study. Distinct from ultrasonography, the sonospectrography system functions by sound transmission and recording through tissues to differentiate between normal and abnormal hips. All hips were examined at four different hip and knee positions. The normal hip served as the control. The sonospectrography system was able to detect unilateral DDH. Dysplastic hips had lower sound transmission values when compared to normal hips in all patients and all four positions; however, the highest (X = 88.8 ± 30.2 Hz) and lowest (X = 8.3 ± 5.4 Hz) sound transmission mean values were obtained at different positions in the normal hips and those with DDH. Sound transmission values of dysplastic hips were always lower than that of normal hips when the hip and knee was flexed during measurements. Sound transmission values decreased with age. The sonospectrography system may offer a new noninvasive method in the diagnosis of unilateral DDH but requires further study of sensitivity and specificity of detecting dysplastic hips without subluxation in newborn infants.

Level of Evidence: Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence.

Background

Type III growth disturbance (T3GD) following reduction for developmental dysplasia of the hip (DDH) is a relatively rare, but potentially devastating complication. This study evaluated the long-term outcomes of patients treated for DDH who developed a T3GD hip compared to those who didn't, with an emphasis on possible risk factors.

Methods

A case-control design was used. All radiographs of a consecutive set of patients with DDH were evaluated. Twenty-two patients (29 hips) developed T3GD. The control group consisted of 57 patients (72 hips) without any sign of growth disturbance. Variables examined included age at reduction, type of reduction and serial radiographic parameters reflecting pre- and post-reduction status. Average age at final follow up was 26 years in the T3GD group and 34 years in the control group.

Results

Evidence of T3GD was first noticed radiographically at 11 months after reduction and healing of the epiphysis occurred an average of 8.5 months later. Univariate analysis demonstrated no increased risk of T3GD related to age at presentation, presence or absence of the ossific nucleus, type of reduction, initial acetabular index or Smith’s centering ratios. However, the Tönnis grade was significantly associated with an increased risk of T3GD. Tönnis grade 4 hips (high-degree dislocations) had 3.43 times greater risk of developing T3GD compared to those with lower dislocations. At maturity, 90% of the T3GD hips were classified as Severin III/IV, compared to 35% of the controls. At last follow-up, 7 of the 29 T3GD hips (32%) had undergone total hip replacement at an average age of 39 years (range 19 to 57 years).

Conclusions

T3GD remains the most severe and devastating complication after treatment of DDH in children. In most cases, poor acetabular development and flattening of the femoral head lead to early degenerative changes in the hip joint. The risk increases in high-degree dislocations, independent of the treatment performed.

Purpose

There is no consensus in the literature regarding the diagnosis and treatment of developmental dysplasia of the hip (DDH). We designed a national questionnaire to assess the various opinions and current practice of paediatric orthopaedic surgeons in the Netherlands regarding the diagnosis and treatment of DDH in children less than 1 year old.

Methods

The questionnaire was sent to all members of the Dutch Paediatric Orthopaedic Society (DPOS). It discusses different methods and criteria used in the diagnosis of DDH, the use of different therapies and the use of different imaging techniques to evaluate the result of treatment.

Results

With 38 responders, the overall response rate to the survey was 67%. Most surgeons use clinical, radiographic and/or ultrasound examination for the diagnosis. The starting point of treatment is usually on the mild part of the DDH spectrum. The Pavlik harness is most popular in the treatment of dislocated hips, whereas in dysplastic hips, most surgeons use a rigid splint. The duration of treatment has a wide range and evaluation of the effect of treatment is predominantly done by radiography.

Conclusions

The diagnosis and treatment of DDH in the Netherlands has as much diversity as the literature has recommendations about this subject. The lack of consensus on many aspects of DDH diagnosis and treatment should form the basis for a discussion among Dutch paediatric orthopaedic surgeons. Using the available evidence, it should be possible to formulate a more uniform protocol for the diagnosis and treatment of DDH.

Purpose

There is no consensus in the literature regarding the diagnosis and treatment of developmental dysplasia of the hip (DDH). We designed a national questionnaire to assess the various opinions and current practice of paediatric orthopaedic surgeons in the Netherlands regarding the diagnosis and treatment of DDH in children less than 1 year old.

Methods

The questionnaire was sent to all members of the Dutch Paediatric Orthopaedic Society (DPOS). It discusses different methods and criteria used in the diagnosis of DDH, the use of different therapies and the use of different imaging techniques to evaluate the result of treatment.

Results

With 38 responders, the overall response rate to the survey was 67%. Most surgeons use clinical, radiographic and/or ultrasound examination for the diagnosis. The starting point of treatment is usually on the mild part of the DDH spectrum. The Pavlik harness is most popular in the treatment of dislocated hips, whereas in dysplastic hips, most surgeons use a rigid splint. The duration of treatment has a wide range and evaluation of the effect of treatment is predominantly done by radiography.

Conclusions

The diagnosis and treatment of DDH in the Netherlands has as much diversity as the literature has recommendations about this subject. The lack of consensus on many aspects of DDH diagnosis and treatment should form the basis for a discussion among Dutch paediatric orthopaedic surgeons. Using the available evidence, it should be possible to formulate a more uniform protocol for the diagnosis and treatment of DDH.

Purpose

The aim of the study was to assess the role of residual hip dysplasia as a risk factor for osteoarthritis (OA) in developmental dysplasia of the hip (DDH).

Methods

Fifty-one patients (60 hips) with late-detected DDH were studied. Reduction had been performed at a mean age of 19 months (range 4–65 months). On radiographs at age 8–10 years, at skeletal maturity, and at long-term follow-up, femoral head coverage was assessed using the migration percentage (MP) and centre-edge (CE) angle. OA was diagnosed if the minimum joint space width of the upper part of the joint was <2.0 mm.

Results

The mean age at the last follow-up was 45 years (range 43–49 years) in patients who had not undergone total hip replacement (THR). Ten patients had developed OA and eight of them had undergone THR at a mean age of 40 years (range 32–47 years). There was a clear association between OA and residual hip dysplasia. At the last follow-up, 37 hips had normal CE angles (20° or higher) and OA had developed in only two of them (5%; 95% confidence interval [CI] 1–18%). Hip dysplasia without subluxation (CE angle 10–19°) was seen in 18 hips, of which 14 hips had good outcome and four had OA (22%; 95% CI 6–48%). Subluxation occurred in five hips, of which one had a good long-term outcome and four had OA (80%; 95% CI 28–99%). In patients without late reconstructive surgery, MP increased from the age of 10 years to skeletal maturity; thereafter, no significant change occurred. The CE angle did not change significantly between the age of 10 years and the last follow-up.

Conclusion

Hip dysplasia without subluxation has a relatively good long-term prognosis. Subluxation is a risk factor for osteoarthritis. Thus, children with MP above 33% and CE angle under 10° should be evaluated for reconstructive surgery in order to improve the long-term outcome.

Developmental dysplasia of the hip (DDH) is a spectrum of disorders affecting the proximal femur and/or acetabulum leading to an abnormal formation of the hip. Genetic factors are involved in the etiology of DDH. Early recognition of DDH affords the best results from treatment and a better knowledge of the genetics of DDH could enhance early diagnosis. Variants in the Type II collagen (COL2A1) and vitamin D receptor (VDR) genes have been associated with patients with osteoarthritis of the hip secondary to DDH, suggesting these genes could contribute to DDH. To see whether there was linkage between the COL2A1/VDR locus and nonsyndromic DDH, we conducted a linkage study on 11 families with multiple cases of DDH. We demonstrated no evidence of linkage between the COL2A1/VDR locus and nonsyndromic DDH (LOD score < −2), suggesting, although variants in these genes could play a role in osteoarthritis in patients with DDH, they do not contribute to nonsyndromic DDH. The search for causal gene variants should proceed with other candidates.

Background

The purpose of this study was to analyze whether hips treated for developmental dysplasia of the hip (DDH) during infancy, which were clinically and radiologically fully normalized by walking age, may become dysplastic again during later growth.

Materials and methods

A total of 150 patients were randomly selected out of a collective of 386 patients treated for DDH at the Department of Orthopaedics at the University of Zurich between 1993 and 2004. Treatment was started at birth and continued for 6 months. All patients had clinically and radiographically normal hips by walking age. The patients did not suffer from other diseases, in particular, neurological or neuromuscular diseases.

Results

We detected four female subjects among the 150 patients who had been successfully treated for DDH, who had developed dysplastic hips in early adolescence, necessitating acetabular surgery.

Conclusion

The successful treatment of DDH in infancy does not ensure normal hip development; therefore, follow up into maturity may be recommended.

Level of evidence

Level IV.

Although the use of ultrasound in the diagnosis and early treatment of developmental dysplasia of the hip (DDH) has reduced the number of patients diagnosed late and decreased the number of operative procedures, surgical treatment is still needed in some patients. Late cases continue to occur as a result of missing the screening examination, being normal at initial screening and missing followup. Dysplasia may persist despite appropriate nonoperative or operative treatment. Many of these patients subsequently undergo closed or open reduction and femoral or acetabular reconstruction. Ultrasound of the hips is generally used up to 6 or 8 months of age, during which time the hips are largely cartilaginous, and radiographs after that time when bony development is more complete. Options to supplement ultrasound and radiography include arthrography, computed tomography, and magnetic resonance imaging. Several advances have been made in the imaging of DDH and its complications including acetabular labral pathology and of femoroacetabular impingement (FAI). We review imaging techniques other than ultrasound used in the management of DDH.

Level of Evidence: Level V, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Developmental dysplasia of the hip (DDH) is a neonatal condition with various causes. Neuromuscular dysplasia of the hip (NDH) is a sequel of neuromuscular disease, and generally presents later in childhood than DDH. Some evidence, however, supports a concept of a neuromuscular etiology of DDH: (1) a high prevalence of spinal dysraphism in DDH; and (2) abnormal sensory evoked potentials in 31% of DDH patients. To explore this suggestion we ascertained the presence of neuromuscular disease within a cohort of DDH patients, and asked whether the neuromuscular condition is the initial etiology of the dysplasia or a coincidental finding. We retrospectively reviewed patients presenting with DDH. Only those with an initial diagnosis of DDH and a subsequent diagnosis of a neuromuscular condition were assessed. Fifteen of 560 patients fulfilled the criteria, however the presence of true DDH within this group was minimal, as several cases emerged as early presenting NDH. We therefore believe it unlikely DDH has a substantial neurological etiology.

Level of Evidence: Level III, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Purpose

Developmental dysplasia of the hip (DDH) is a leading cause of disability in childhood and early adult life. Clinical and sonographic screening programmes have been used to facilitate early detection but the effectiveness of both screening strategies is unproven. This article discusses the role for screening in DDH and provides an evidence-based review for early management of cases detected by such screening programmes.

Methods

We performed a literature review using the key words ‘hip dysplasia,’ ‘screening,’ ‘ultrasound,’ and ‘treatment.’

Results

The screening method of choice and its effectiveness in DDH still needs to be established although it seems essential that screening tests are performed by trained and competent examiners. There is no level 1 evidence to advise on the role of abduction splinting in DDH although clinicians feel strongly that hip instability does improve with such a treatment regime. The definition of what constitutes a pathological dysplasia and when this requires treatment is also poorly understood.

Conclusion

Further research needs to establish whether early splintage of clinically stable but sonographically dysplastic hips affects future risk of late-presenting dysplasia/dislocation and osteoarthritis. There is a need for high quality studies in the future if these questions are to be answered.

Background

Osteonecrosis (ON) of the femoral head is one of the main complications associated with treatment of developmental dysplasia of the hips (DDH). The reported rates of ON vary widely between 6% and 48%, suggesting varying factors in these studies influence the rate. Several studies suggest open reduction combined with femoral shortening provides protection against ON. However, it is unclear whether confounders such as failed Pavlik harness treatment, preliminary traction, closed versus open reduction, and redislocation influence the rate of ON.

Questions/purpose

We therefore asked whether open reduction with concomitant osteotomies without femoral shortening, redislocation, and secondary surgical procedures for residual acetabular dysplasia influenced the rate of ON.

Methods

We retrospectively reviewed 64 children (78 hips) hospitalized with developmental dislocation of the hip between January 1998 and February 2007. Patients younger than 12 months were treated with closed or open reduction. Open reduction combined with concomitant pelvic and femoral osteotomies was performed in patients past walking age. ON was diagnosed from radiographs obtained at last followup. We used logistic regression analysis to identify predictors for the development of ON. The minimum followup was 3.2 years (mean, 6.8 years; range, 3.2−11.5 years).

Results

The overall rate of ON was 40%. Patients who underwent open reduction combined with concomitant osteotomies, experienced redislocation, or required secondary reconstructive procedures after initial reduction were at higher risk for having ON develop.

Conclusions

We advocate early reduction of the dislocated hip in the first year of life to avoid the need for concomitant osteotomies combined with open reduction.

Level of Evidence

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

We have reviewed 17 patients (18 hips) who required repeat open reduction for recurrent or persistent dislocation after a previous attempt at open reduction for developmental dysplasia of the hip (DDH). The mean follow-up was 5.5 (3–15) years. At the review, five patients were limping and had limited hip motion but no pain. Six hips were classified as Severin class III or more, and avascular necrosis was evident in 11. We suggest that technical failure is usually the cause for re-dislocation in unilateral cases, as we discovered at repeat open reduction in five of six patients with unilateral dislocation. The biological behaviour of bilateral dislocations may in someway be different since in nine of 11 patients with bilateral dislocations, no obvious cause could be attributed. The outcome is usually poor.

Background

Previous studies show the shape of the femur in developmental dislocation of the hip (DDH) becomes more abnormal with increasing subluxation. Two kinds of high dislocations associated with DDH have been observed in clinical practice, one with (Type C1) and one without (Type C2) a false acetabulum. The presence or absence of a false acetabulum in high dislocated hips is associated with different loading patterns and could influence the development and shape of the proximal femur.

Questions/purposes

We therefore determined whether (1) the proximal femoral shape and dimension in Type C1 and Type C2 hips differ from each other, and (2) the femur dislocated with the same height in Types C1 and C2 hips.

Patients and Methods

We examined the following variables on 54 proximal femurs from 54 patients with high DDH (28 Type C1 hips and 26 Type C2 hips) on AP and lateral radiographs; the ML widths of the cortical and medullary canals, height of the femoral head, height of dislocation, and height of the greater trochanter. Reproducibility of the measurements was tested by two researchers with high interobserver and intraobserver agreement.

Results

The proximal femur in Type C2 hips was narrower and stovepipe shaped, with a smaller flare index (2.7 ± 0.6), compared with Type C1 hips (3.5 ± 1.2). The proximal femur migrated an average of 18 mm more superiorly in Type C2 than in Type C1 hips.

Conclusions

Our data confirm distinctions in the shape of the proximal femur in the presence and absence of a false acetabulum.

Clinical Relevance

Owing to the abnormal shapes, special implants of different geometries or modular stems may be needed for reconstruction Type C2 high dislocations.

Ludloff’s medial approach has been described as a simple procedure for open reduction of developmental dysplasia of the hip (DDH) requiring minimal dissection and tissue disruption. Many patients undergo subsequent reconstruction of the acetabulum after skeletal maturity for residual dysplasia. Femoral head deformity reportedly influences the long-term outcome of these osteotomies. The literature suggests this deformity may be related to the patient’s age at the time of a medial approach. We therefore asked whether femoral head deformity (roundness index, femoral head enlargement) at skeletal maturity correlates with patient age at surgery. We assessed the radiographs of 40 patients (42 hips). Their mean age at surgery was 14.3 months (range, 6–31 months); the minimum followup was 10 years (mean, 15.8 years; range, 10–27 years). The mean roundness index at skeletal maturity correlated with increased age at the time of the operation (mean index, 58.3; range, 47–79) while enlargement did not. Using a medial approach for correction of DDH in older patients increases the risk of femoral head deformity at skeletal maturity.

Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Background

Clinicians use various criteria to diagnose developmental dysplasia of the hip (DDH) in early infancy, but the importance of these various criteria for a definite diagnosis is controversial. The lack of uniform, widely agreed-on diagnostic criteria for DDH in patients in this age group may result in a delay in diagnosis of some patients.

Questions/Purposes

Our purpose was to establish a consensus among pediatric orthopaedic surgeons worldwide regarding the most relevant criteria for diagnosis of DDH in infants younger than 9 weeks.

Material and Methods

We identified 212 potential criteria relevant for diagnosing DDH in infants by surveying 467 professionals. We used the Delphi technique to reach a consensus regarding the most important criteria. We then sent the survey to 261 orthopaedic surgeons from 34 countries.

Results

The response rate was 75%. Thirty-seven items were identified by surgeons as most relevant to diagnose DDH in patients in this age group. Of these, 10 of 37 (27%) related to patient characteristics and history, 13 of 37 (35%) to clinical examination, 11 of 37 (30%) to ultrasound, and three of 37 (8%) to radiography. A Cronbach alpha of 0.9 for both iterations suggested consensus among the panelists.

Conclusion

We established a consensus regarding the most relevant criteria for the diagnosis of DDH in early infancy and established their relative importance on an international basis. The highest ranked clinical criteria included the Ortolani/Barlow test, asymmetry in abduction of 20° or greater, breech presentation, leg-length discrepancy, and first-degree relative treated for DDH.

Level of Evidence

Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

We reviewed long-term outcomes after open reduction by the medial approach for developmental dislocation of the hip (DDH). Forty-five hips in 43 patients with more than ten years of follow-up were assessed clinically and radiologically. The mean age at surgery was 14.0 (range 6–31) months, and the follow-up period ranged from ten to 28 years (mean 16.4 years). We compared the good (18 hips) and poor groups (27 hips) as classified by the Severin classification. The mean age at surgery was significantly older in the poor group than the good group (17.1 and 9.4 months, respectively, P < 0.001). Thirteen (29%) of 45 hips had avascular necrosis (AVN) of the femoral head. The mean age at surgery was significantly older in the patients with AVN than without AVN (20.0 and 11.6 months, respectively, P < 0.001). Another approach, such as the wide exposure method, should be selected for DDH with increased age at operation.

Radiographic evaluation provides essential information regarding the diagnosis and treatment of musculoskeletal disorders. We evaluated the ability of hip specialists to reliably identify important radiographic features and to make a diagnosis based on plain radiographs alone. Five hip specialists and one fellow performed a blinded radiographic review of 25 control hips, 25 hips with developmental dysplasia (DDH), and 27 with femoroacetabular impingement (FAI). On two separate occasions, readers assessed acetabular version, inclination and depth, position of the femoral head center, head sphericity, head-neck offset, Tönnis grade, and joint congruency. Observers made a diagnosis categorizing each hip as normal, dysplastic, FAI, or combined DDH and FAI (features of both). Reliability was determined using Cohen’s kappa coefficient. Intraobserver values were highest for acetabular inclination (κ = 0.72) and determination of femoral head center position (κ = 0.77). Interobserver reliability values were highest for acetabular inclination (κ = 0.61) and Tönnis osteoarthritis grade (κ = 0.59). All other measurements, including diagnosis, had kappa values less than 0.55. We concluded many of the standard radiographic parameters used to diagnose DDH and/or FAI are not reproducible. Accordingly, a more clear set of definitions and measurements must be developed to allow for more reliable diagnosis of early hip disease.

Level of Evidence: Level III, diagnostic study. See the guidelines for authors for a complete description of the levels of evidence.

Three different types of congenital hip disease in adults have been distinguished based upon the position of the femoral head relative to the acetabulum and the underlying pathoanatomy of the joint: (1) dysplasia; (2) low dislocation; and (3) high dislocation. To facilitate classification of borderline or ambiguous cases, we studied the morphologic variations of low and high dislocation as observed on the radiographs of 101 hips with low and 74 hips with high dislocation. In low dislocation, 54 hips (53.5%) had extended coverage of the true acetabulum (Type B1) and 47 hips (46.5%) had limited coverage (Type B2). Among the cases with high dislocation, a false acetabulum with an adjacent femoral head occurred in 46 hips (62.2%) (Type C1), and the femoral head was floating within the gluteal muscles in 28 hips (37.8%) (Type C2). The kappa value for interobserver agreement between two raters who made radiographic measurements was 0.963, and for intraobserver agreement between the two evaluations of the same observer it was 0.946 and 0.971, respectively. The two types of low and high dislocation were associated with high intra- and interobserver agreement. Whether these distinctions have clinical utility requires further validation.

Level of Evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Hip stresses are generally believed to influence whether a hip develops osteoarthritis (OA); similarly, various osteotomies have been proposed to reduce contact stresses and the risk of OA. We asked whether elevated hip contact stress predicted osteoarthritis in initially asymptomatic human hips. We identified 58 nonoperatively treated nonsubluxated hips with developmental dysplasia (DDH) without symptoms at skeletal maturity; the control group included 48 adult hips without hip disease. The minimum followup was 20 years (mean, 29 years; range, 20–41 years). Peak contact stress was computed with the HIPSTRESS method using anteroposterior pelvic radiographs at skeletal maturity. The cumulative contact stress was determined by multiplying the peak contact stress by age at followup. We compared WOMAC scores and radiographic indices of OA. Dysplastic hips had higher mean peak contact and higher mean cumulative contact stress than normal hips. Mean WOMAC scores and percentage of asymptomatic hips in the study group (mean age 51 years) were similar to those in the control group (mean age 68 years). After adjusting for gender and age, the cumulative contact stress, Wiberg center-edge angle, body mass index, but not the peak contact stress, independently predicted the final WOMAC score in dysplastic hips but not in normal hips. Cumulative contact stress predicted early hip OA better than the Wiberg center-edge angle.

Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

The radiological and clinical picture of a developmental hip dislocation and a severe subluxation are identical. According to Leveuf and Wiberg the diagnosis can only be made by arthrography. The differential diagnosis is critical, as treatment differs dependent on the diagnosis. In this study, the diagnosis of subluxation was based on a plain radiograph of the pelvis. A radiograph of the pelvis with the hips abducted at least 45° and internally rotated (AIR view) was used to differentiate these two entities. In subluxations, the femoral head will relocate into the acetabulum with perfect or near perfect reconstitution of the Shenton's line. It will fail to do so in true dislocations. Five patients, mean age 14.6 months (range 9 to 20 months), presented with delayed diagnosis of hip dysplasia. The examination revealed minimal or no limitation of hip abduction, a leg length discrepancy, and a Trendelenburg gait in the three walking age girls. The radiograph suggested a hip dislocation. The diagnosis of hip subluxation was based on the relocation of the femoral head with the abduction/internal rotation radiograph. All were successfully treated with an Ilfeld abduction splint. None had examination with general anesthesia, arthrograms, traction or immobilization in spica cast. Avoiding over diagnosis of hip dislocation in cases of subluxation is important. This is necessary to prevent overtreatment and to accurately assess the results of treatment. The abduction/internal rotation view may achieve this goal while avoiding diagnostic and therapeutic procedures, such as arthrograms, cast immobilization and surgery.

Objective

To review the effectiveness of, and make practice recommendations for, serial clinical examination and ultrasound screening for developmental dysplasia of the hip (DDH) in newborns. The effectiveness of selective screening of high-risk infants with hip and pelvic radiographs and treatment with abduction therapy are also examined.

Options

Screening: serial clinical examination, ultrasound screening, radiographic evaluation. Treatment: abduction therapy.

Outcomes

Rates of operative intervention, abduction splinting, delayed diagnosis of DDH (beyond 3–6 months), treatment complications and false diagnostic labelling. Long-term functional outcomes were considered important.

Evidence

MEDLINE was searched for relevant English-language articles published from 1966 to November 2000 using the key words “screening,” “hip,” “dislocation,” “dysplasia,” “congenital” and “ultrasound.” Comparative and descriptive studies and key reviews were retrieved, and their bibliographies were manually searched for further studies.

Benefits, harms and costs

Because most infants will have spontaneous resolution of nonteratologic DDH, early identification and intervention results in unnecessary labelling of newborns as having the problem and unnecessary treatment. Ultrasound screening is a highly sensitive but poorly specific measure of clinically relevant DDH. Abduction splinting is associated with a variety of problems, and its effectiveness in treating DDH is not clearly known. At least 20% of infants requiring operative intervention have had splint therapy. The harms of labelling, repetitive investigations, unnecessary splinting and resource consumption associated with screening are substantial.

Values

The strength of evidence was evaluated using the evidence-based methods of the Canadian Task Force on Preventive Health Care.

Recommendations

· There is fair evidence to include serial clinical examination of the hips by a trained clinician in the periodic health examination of all infants until they are walking independently (level II-1 and III evidence; grade B recommendation). · There is fair evidence to exclude general ultrasound screening for DDH from the periodic health examination of infants (level II-1 and III evidence; grade D recommendation). · There is fair evidence to exclude selective screening for DDH from the periodic health examination of high-risk infants (level II-1 and III evidence; grade D recommendation). · There is fair evidence to exclude routine radiographic screening for DDH from the periodic health examination of high-risk infants (level III evidence; grade D recommendation). · There is insufficient evidence to evaluate the effectiveness of abduction therapy (level III evidence; grade C recommendation), but good evidence to support a period of close observation for newborns with clinically detected DDH (level I evidence; grade A recommendation). However, there is insufficient evidence to determine the optimal duration of observation (level III evidence; grade C recommendation).

Validation

The members of the Canadian Task Force on Preventive Health Care reviewed the findings of this analysis through an iterative process. The task force sent the final review and recommendations to selected external expert reviewers, and their feedback was incorporated in the final draft of the manuscript.

Sponsors

The Canadian Task Force on Preventive Health Care is funded through a partnership between the Provincial and Territorial Ministries of Health and Health Canada.

Background

Implementation of medical interventions may vary with organization and available capacity. The influence of this source of variability on the cost-effectiveness can be evaluated by computer simulation following a carefully designed experimental design. We used this approach as part of a national implementation study of ultrasonographic infant screening for developmental dysplasia of the hip (DDH).

Methods

First, workflow and performance of the current screening program (physical examination) was analyzed. Then, experimental variables, i.e., relevant entities in the workflow of screening, were defined with varying levels to describe alternative implementation models. To determine the relevant levels literature and interviews among professional stakeholders are used. Finally, cost-effectiveness ratios (inclusive of sensitivity analyses) for the range of implementation scenarios were calculated.

Results

The four experimental variables for implementation were: 1) location of the consultation, 2) integrated with regular consultation or not, 3) number of ultrasound machines and 4) discipline of the screener. With respective numbers of levels of 3,2,3,4 in total 72 possible scenarios were identified. In our model experimental variables related to the number of available ultrasound machines and the necessity of an extra consultation influenced the cost-effectiveness most.

Conclusions

Better information comes available for choosing optimised implementation strategies where organizational and capacity variables are important using the combination of simulation models and an experimental design. Information to determine the levels of experimental variables can be extracted from the literature or directly from experts.

Introduction

Developmental dysplasia of the hip (DDH) is a common skeletal disease, which is characterized by abnormal seating of the femoral head in the acetabulum. Genetic factors play a considerable role in the etiology of DDH. Asporin (ASPN) is an ECM protein which can bind to TGF-β1 and sequentially inhibit TGF-β/Smad signaling. A functional aspartic acid (D) repeat polymorphism of ASPN was first described as an osteoarthritis-associated polymorphism. As TGF-β is well known as an important regulator in the development of skeletal components, ASPN may also be involved in the etiology of DDH. Our objective is to evaluate whether the D repeat polymorphism of ASPN is associated with DDH in Han Chinese.

Methods

The D repeat polymorphism was genotyped in 370 DDH patients and 445 control subjects, and the allelic association of the D repeat was examined.

Results

From D11 to D18, eight alleles were identified. D13 allele is the most common allele both in control and DDH groups, the frequencies are 67.3% and 58.1% respectively. In the DDH group, a significantly higher frequency of the D14 allele and significantly lower frequency of D13 was observed. The association of D14 and D13 was found in both females and males after stratification by gender. There was no significant difference in any other alleles we examined.

Conclusions

Our results show an obvious association between the D repeat polymorphism of ASPN and DDH. It indicates that ASPN is an important regulator in the etiology of DDH.

Femoroacetabular impingement is a motion-based concept of conflict that occurs secondary to morphologic abnormalities of the proximal femur and/or acetabulum. Creating impingement-free motion through restoration of normal morphology serves as the goal of joint-preserving procedures. We retrospectively reviewed the short-term functional and radiographic outcomes of 46 patients (48 hips) with femoroacetabular impingement treated with a surgical dislocation and restoration of offset. The average Merle D’Aubigné-Postel score improved from a preoperative of 13 (range, 7–16 ± 1.7) to a postoperative score of 16.8 (range, 12–18 ± 1.3). Creating impingement-free motion via a surgical dislocation improves symptoms in patients with limited radiographic signs of arthritis who are experiencing impingement-related hip pain.

Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Background

Total hip arthroplasty (THA) in the presence of developmental dysplasia of the hip (DDH) can be technically challenging. Restoring the anatomic center of hip rotation may require femoral osteotomy. Techniques using cementless components are widely reported but less is known about using cemented components that may be more appropriate with osteopenic bone.

Questions/purposes

We therefore determined the rate of union, complications, and early functional score in a series of patients with DDH who underwent cemented THA and simultaneous subtrochanteric osteotomy.

Methods

We retrospectively reviewed 28 patients (35 hips) who underwent a cemented THA for DDH at a mean age of 47.3 years. Two patients (two hips) died within 12 months of surgery of unrelated conditions. The clinical notes and radiographs were reviewed with a minimum followup of 2 years (mean, 5.6 years; range, 2–14 years). Complications were noted. SF-12 and Oxford hip scores (OHS) were recorded for 18 patients preoperatively and after 6 and 12 months.

Results

Union occurred in 32 of 33 femora (97%); one patient had an infected nonunion. The overall revision rate was 20% (9% femoral revision rate). There were three dislocations, two of which had further surgery. Two patients had a transient neuropraxia. The mean SF-12 physical component score increased from 32 to 52 and mean SF-12 mental component score increased from 48 to 51. The mean OHS decreased from 40 to 27.

Conclusion

Combined subtrochanteric osteotomy and cemented THA is technically demanding with a higher complication rate than routine THA. The rate of union, complications, implant survival, and early OHS were comparable to those for similar techniques using cementless components.

Level of Evidence

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.