Overhead Bryant's Traction Does Not Improve the Success of Closed Reduction or Limit AVN in Developmental Dysplasia of the Hip

Preoperative Gallows traction as an adjunct to hip open reduction surgery: Is it safe and is it effective?

Background

Traction is used at our hospital before open reduction in infants with developmental dysplasia of the hip. Theoretically, it reduces soft-tissue tension, allowing an easier surgical reduction and therefore lower surgical complications. Owing to extended hospital stays, potential complications, and lack of evidence, the use of traction has decreased. This study aims to quantify whether traction is safe and whether it has any demonstrable effect.

Methods

The perioperative course of 80 patients undergoing preoperative traction and hip open reduction were reviewed. The height of hip dislocation was classified using the International Hip Dysplasia Institute classification system on both radiographs taken before and after traction. Any complications related to traction were recorded, along with the requirement for femoral shortening osteotomies, incidence of re-dislocation, and longer-term rate of avascular necrosis.

Results

Traction lowered the resting position of the majority of hips, with the median International Hip Dysplasia Institute grade before traction improving from 4 to 3, a statistically significant improvement (p < 0.00001). There were no neurovascular complications. Two babies were complicated with broken skin sores; however, surgery still progressed uneventfully. Zero hips in the cohort required femoral shortening osteotomies to achieve a tension-free reduction, and the re-dislocation rate was 0%. However, 96% of hips were Severin 1 or 2 at 6-year follow-up.

Conclusion

Notably, 1 week of preoperative traction significantly improves the resting position of the hip in high dislocations. It is safe when used in infants weighing <12 kg, and subsequent surgical outcomes are excellent, thus supporting its use ahead of developmental dysplasia of the hip open reduction surgery.

Level of evidence

Level IV.

The efficacy of gradual reduction using two-stage traction for developmental dysplasia of the hip in southern China

Purpose

This study aimed to report the preliminary outcome of gradual reduction (GR) utilizing two-stage traction (TST) compared with traditional traction (TT) in the treatment of developmental dysplasia of the hip (DDH) and to evaluate whether the prognosis of the TST is better than that of TT.

Methods

The following information on children diagnosed with DDH who underwent treatment with GR using two-stage traction or traditional traction between June 2016 and August 2017 was collected: sex, age, weight, acetabular index (AI), International Hip Dysplasia Institute (IHDI) classification, femoral head ossification, traction time, reduction quality, and labrum shape in arthrography. The AI, IHDI classification, second operation rate, and incidence of femoral head avascular necrosis (AVN) were analyzed after the final comprehensive 1-year follow-up.

Results

In this study, 27 cases (31 hips: 18 left and 13 right) were enrolled, with 18 hips (16 cases) assigned to the TT group and 13 hips (11 cases) assigned to the TST group, with the corresponding average age at diagnosis of 5.56 ± 1.66 and 4.06 ± 1 months (p < 0.001). For both TT and TST groups, the average age at operation was 6.01 ± 1.67 and 65 ± 0.86 months (p = 0.435), the distribution of affected left and right sides was 10/8 and 8/5 hips (p = 1), and the average initial AI was 37.11 ± 3.26 and 36.77 ± 4.34 (p = 0.804), respectively. IHDI classification III/IV was observed in 15/3 and 11/2 hips, respectively (p = 1). Femoral head ossification was present in 6/18 hips in the TT group and 2/13 hips in the TT group (p = 0.412). The total traction time was 13.22 ± 2.6 days for the TT group and 49.23 ± 25.77 days for the TST group (p < 0.001). After GR, IHDI classification III/IV was observed in 9/9 and 12/1 hips, respectively (p = 0.02). AVN was present in 5/18 hips in the TT group and 0/13 hips in the TST group (p = 0.048), while the need for a second operation was approved in 5/18 hips in the TT group and 1/13 hips in the TST group (p = 0.359) at the final follow-up.

Conclusions

Two-stage traction can significantly decrease the ratios of IHDI classifications III and IV and the incidence of AVN compared to traditional traction; also, it significantly reduces the total traction time.

The Effect of Traction before Closed Reduction in Patients with Developmental Dysplasia of the Hip

Developmental dysplasia of the hip (DDH) with a dislocated hip can be treated with traction before closed reduction (CR). Currently, there is insufficient evidence supporting the use of preoperative traction treatment for a successful CR. The objective of this study was to determine the effect of preoperative traction on the success rate of primary CR in DDH patients with dislocated hips. A retrospective pair-matched study was performed in DDH patients with dislocated hips. Patients with preoperative traction treatment prior to primary CR were matched (based on age and the severity of DDH on the radiograph) to patients without preoperative traction treatment. The primary outcome was the presence or absence of maintained reduction after three weeks. A match was found for 37 hips, which resulted in the inclusion of 74 hips. No significant difference was found in the number of successful reductions after three weeks between the traction group and the control group (31 vs. 33 hips, p = 0.496). Traction treatment did not significantly improve the short-term or mid-term outcomes for closed reduction. Based on these results, we suggest that traction treatment should not be used as standard care for dislocated hips in DDH.

Avascular Necrosis of the Hip Compromises Gait Balance Control in Female Juveniles With Unilateral Developmental Dysplasia Treated in Toddlerhood

Avascular necrosis of the hip (AVN) is one of the most severe complications of surgical reduction when treating developmental dysplasia of the hip (DDH). The current study identified the differences in the balance control during walking in terms of the inclination angle (IA) of the center of pressure (COP) to the center of mass (COM), and the rate of change of IA (RCIA) between female juveniles with and without secondary AVN at the hip who were treated for unilateral DDH during toddlerhood as compared to their healthy peers. When compared to female healthy controls, the non-AVN group showed bilaterally similar compromised balance control with significantly decreased IA (p < 0.05) but increased RCIA (p < 0.04) in the sagittal plane during single-limb support (SLS) of the unaffected side, and in the frontal plane during terminal double-limb support (DLS) of the affected side. In contrast, the AVN increased between-side differences in the sagittal IA (p = 0.01), and sagittal and frontal RCIA during DLS (p < 0.04), leading to bilaterally asymmetrical balance control. Secondary AVN significantly reduced IA and RCIA in the sagittal plane (p < 0.05), and reduced range of RCIA in the frontal plane during initial DLS (p < 0.05). The trend reversed during terminal DLS, indicating a conservative COM-COP control in the sagittal plane and a compromised control in the frontal plane during body weight acceptance, with a compromised COM-COP control in the frontal plane during weight release. The current results suggest that increased between-side differences in the sagittal IA, and sagittal and frontal RCIA during DLS are a sign of AVN secondary to treated unilateral DDH in female juveniles, and should be monitored regularly for early identification of the disease.

Outpatient Bryant's Overhead Traction Does Not Affect the Rate of Open Reduction or Avascular Necrosis in Developmental Dislocation of the Hip

BACKGROUND

The efficacy of preliminary traction to increase the likelihood of closed reduction and/or decrease the incidence of avascular necrosis in the management of developmental dysplasia of the hip (DDH) is controversial. We sought to document compliance with and effectiveness of Bryant's outpatient traction in patients with idiopathic DDH.

METHODS

Patients presenting between 6 and 24 months of age with idiopathic irreducible DDH were prospectively enrolled in the study. Prereduction outpatient traction was prescribed at participating surgeons' preference and parents' expressed willingness to comply with a traction protocol of at least 14 hours/day for 4 weeks. Traction hours were documented using a validated monitor; parents also reported average daily usage. Rate of successful closed reduction and evidence of capital epiphyseal growth disturbance 1 year' and 2 years' postreduction were documented.

RESULTS

Ninety-six patients with 115 affected hips were enrolled. Reliable recorded traction hours were obtained in 31 patients with 36 affected hips. Defining compliance as 14 hours/day average use, 14 of 31 patients (45.2%) were compliant, 2 (6.5%) admitted noncompliance, while 15 (48.2%) claimed to be compliant, but were not. Overall, 68/115 hips (59.0%) were closed reduced. Age at treatment was the only demographic characteristic associated with an increased incidence of closed reduction (11.7 vs. 14.6 mo, P<0.01). Successful closed reduction was achieved in 10/16 hips (62.5%) of compliant patients, 12/20 (60.0%) of noncompliant patients, and 43/72 (59.7%) of no-traction patients. Irregular ossific nucleus development was noted 1-year postindex reduction in 5/16 (31.3%) of complaint-patient hips and 25/92 (27.2%) of noncomplaint and no-traction hips. Distorted proximal femoral epiphysis was noted at 2 years postreduction in 2/15 hips (13.3%) of compliant patients and 15/52 hips (28.8%) in noncompliant and no-traction patients. None of these differences was statistically significant.

CONCLUSIONS

Parent-reported use of outpatient traction is unreliable. Four weeks of outpatient overhead Bryant's traction did not affect the rate of closed reduction or avascular necrosis in late-presenting DDH in this cohort.

LEVEL OF EVIDENCE

Level II-prospective cohort.

Bilateral Asymmetry in Balance Control During Gait in Children with Treated Unilateral Developmental Dysplasia of the Hip

INTRODUCTION

About 1% of the newborn population has developmental dysplasia of the hip (DDH), altering joint biomechanics, gait performance and balance control. Pemberton's osteotomy is used in early treatment but it remains unclear whether it will help the patient regain normal balance control during gait. The current study aimed to identify the changes of the whole-body balance control during level walking in children treated for unilateral DDH during toddlerhood, in terms of inclination angles (IA) of the line joining the body's center of mass (COM) and center of pressure (COP), and the rate of change of IA (RCIA).

MATERIALS AND METHODS

Twelve girls (DDH group; age: 7.1 ± 2.1 years) who had been treated with Pemberton's osteotomy for unilateral DDH during toddlerhood and twelve healthy controls (Control group; age: 7.6 ± 2.1 years) walked at their preferred walking speed while IA, RCIA and temporal-spatial parameters were calculated from measured kinematic and forceplate data, and were compared using independent t-tests.

RESULTS

Compared to the Control group, the DDH group showed significantly decreased sagittal IA (p = 0.042) but increased range of sagittal RCIA during SLS on the unaffected side (p = 0.006), and increased peak sagittal RCIA during DLS (p < 0.008). In the frontal plane, the altered COM-COP control occurred mainly during stance phase of the affected side, showing a decreased range of RCIA during SLS (p = 0.033) followed by decreased IA (p = 0.045) with an increased peak value of RCIA (p = 0.023) during terminal DLS.

CONCLUSIONS

The children with treated unilateral DDH showed compromised, bilaterally different balance control strategies with altered COM-COP control during gait, not only during stance in the frontal plane as expected, but even more so during swing in the sagittal plane. It is thus suggested that routine assessment of the morphological changes and/or altered balance control of both the unaffected and affected hips is equally important for early identification of any signs of insidious hip problems, deteriorating balance control or increased risk of loss of balance.

Petit-Morel method for hip development dysplasia in toddlers: A retrospective observational study in 34 patients

BACKGROUND

The Petit-Morel method allows the treatment of developmental hip dysplasia in toddlers by combining gradual traction to achieve reduction followed by immobilisation during which pelvic osteotomy is performed. The objective of this study was to assess the radiographic and clinical outcomes in a retrospective cohort of patients.

HYPOTHESIS

The Petit-Morel method is associated with low rates of avascular necrosis and residual acetabular dysplasia at skeletal maturity, as well as with satisfactory medium-term clinical outcomes.

MATERIAL AND METHODS

We conducted a single-centre retrospective study of 34 patients (35 hips) treated between 1997 and 2014. The radiological assessment criteria included an evaluation for avascular necrosis classified according to Kalamchi and MacEwan, the vertical centre edge (VCE) angle, femoral head sphericity according to Mose, and acetabular dysplasia at skeletal maturity according to Severin. Hip function was assessed by determining the Postel-Merle d'Aubigné (PMA) score.

RESULTS

Mean age at treatment was 19±4 months (range, 14-29). Mean follow-up was 11 years (range, 5-20). There were two failures including one case of recurrent dislocation requiring surgical reduction. Group II avascular necrosis occurred in 1 (3%) patient. Tönnis Grade IV dysplasia was significantly associated with resolving irregularity of the ossification centre, seen in 19 (54%) cases (p=0.002). In the 18 patients followed-up to skeletal maturity, with a mean follow-up of 15 years (range, 12-20 years), 17 hips were Severin Class I. The mean VCE angle was 29° (range, 15°-38°), and the head was spherical for 34 (98%) hips. The PMA score at last follow-up was excellent (17-18). The mean VCE angle was greater in all 5 patients who experienced pain during long walks (35° [range, 32°-37°]) than in the asymptomatic patients (28° [range, 15°-38°]) (p=0.009).

DISCUSSION

The Petit-Morel method is a reliable treatment that provides good clinical and radiological outcomes. Overcorrection of the VCE angle was noted in the patients who experienced walking-related pain in adulthood.

LEVEL OF EVIDENCE

IV, retrospective observational cohort study.

Narrative Review of Complications Following DDH Treatment

BACKGROUND

The purpose of this narrative review was to survey the literature for common complications following treatment of DDH in children less than 4 years old.

METHODS

The Pubmed database was queried. Search result titles were reviewed to identify papers that were pertinent to the topic. Abstracts for these papers were obtained and read, and a subset of these were selected for review of the complete manuscript.

RESULTS

92 manuscripts were reviewed. Residual dysplasia, redislocation, and osteonecrosis are the primary complications of treatment in this age group. In the long term, hips without complications related to DDH treatment tend to do well, although a significant percentage of them will inevitably require joint replacement surgery.

CONCLUSION

Although there is excellent potential for a good outcome when DDH is diagnosed and treated under age 4 years, osteonecrosis continues to be a concern with all treatment methods. A subset of patients from this young cohort will continue to have residual dysplasia or recurrent dislocation requiring return to the operating room.

The effectiveness of preliminary traction in the treatment of congenital dislocation of the hip

Background

Historical papers on the treatment of congenital dislocation of the hip suggest the use of preliminary traction to facilitate closed reduction or to decrease the risk of avascular necrosis (AVN) of the femoral head. In the 1980s, some authors questioned the role of preliminary traction and suspended its use, yielding satisfactory results. Since then, several studies called into question this method, and some authors have continued to recommend preliminary traction while other authors have discouraged its use.

Materials and methods

We reanalysed the full set of radiographs of 71 hips (52 patients) surgically treated by a medial approach after 4 weeks of preoperative longitudinal traction. The mean age at operation was 16 months. Before and after traction, the height of the dislocation was graded according to the Gage and Winter method. The hips were divided into two groups: group 1, in which the traction was effective, and group 2, in which the traction was not effective. These two groups were statistically analysed regarding the severity of the dislocation, the age of the patient at surgery and the incidence of AVN.

Results

Preliminary traction was effective in 48 hips (68%, group 1), while it was not effective in the remaining 23 (32%, group 2). The effectiveness of preliminary traction was statistically related to the height of the dislocation and to the age of the patient at surgery, with traction being less effective in more severe dislocations and in older children. The incidence of AVN was statistically lower in group 1 than in group 2.

Conclusions

In our study population, despite not having a control group, preliminary traction—when effective—seemed to reduce the incidence of AVN in patients surgically treated for congenital dislocation of the hip. The effectiveness of the traction was influenced by the severity of the dislocation and the age of the patient; it worked better for less severe dislocations and in younger children. To reduce hospital costs, traction should be applied at home.

Level of evidence

3.

Efficacy of closed reduction for developmental dysplasia of the hip: midterm outcomes and risk factors associated with treatment failure and avascular necrosis

BACKGROUND

The purpose of this study was to evaluate the efficacy of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) and to investigate risk factors associated with CR failure and avascular necrosis (AVN) occurrence in follow-ups.

METHODS

The study retrospectively included 110 patients and 138 hips with DDH diagnosis that underwent closed reduction between February 2012 and November 2015 in our single tertiary medical institution. The failure rate of CR and the underlying risk factors were evaluated. Meanwhile, the incidence of AVN and the related risk factors among the successful CR cases were assessed.

RESULTS

The overall failure rate of DDH treated by CR in the present study was 31.16% (43/138). Risk factors for the CR failure were older age at the time of CR (≥ 18.35 month), large medical interval before CR (≥ 35.35 mm), and severer dislocation of the affected hip (IDHI grades III and IV). The incidence of AVN was 8.33% (6/72) in patients with successful CR at the last follow-up. No significant risk factors had been established in the present study that associated with the AVN occurrence.

CONCLUSIONS

For the treatment of DDH with CR, patients with younger age might achieve better outcomes; early diagnosis and early treatment might be the key point in the DDH treatment.

Effect of age on radiographic outcomes of patients aged 6-24 months with developmental dysplasia of the hip treated by closed reduction

This study aimed to investigate the effect of age on the rates of redislocation, avascular necrosis (AVN) of the femoral head, and final radiographic outcomes in patients with developmental dysplasia of the hip (DDH) treated with closed reduction. A total of 308 hips (276 patients) with DDH treated with closed reduction were included and divided into three groups according to age (<12, 12-18, 18-24 months). Tönnis grade, rate of redislocation and AVN, Severin radiographic grade, and risk of surgery were evaluated on radiographs. Tönnis grade significantly increased with age (P < 0.001). Redislocation occurred in 17 (5.5%) and AVN occurred in 36 (11.7%) hips. The rate of redislocation and AVN was similar among the three age groups in all Tönnis grades. However, redislocation rate significantly increased with Tönnis grade (P = 0.027). Overall, 246 hips (79.9%) had satisfactory final outcomes, and 62 hips (20.1%) had unsatisfactory outcome; no difference was observed among three age groups. A total of 103 hips (33.4%) were found to be at risk for secondary surgery. The surgical risk (25%) in patients younger than 12 months was lower than that of older patients (12-18 months: 34.4%; 18-24 months: 37.9%). Logistic regression analysis also confirmed that age was not a risk factor for redislocation, AVN, or poor radiographic outcome. In conclusion, age has no significant impact on redislocation and AVN in patients aged 6-24 months with DDH treated by closed reduction. Although older patients have a higher risk developing residual acetabular dysplasia, secondary pelvic surgery provides favorable outcomes in most patients.

Does the size of the femoral head correlate with the incidence of avascular necrosis of the proximal femoral epiphysis in children with developmental dysplasia of the hip treated by closed reduction?

PURPOSE

The purpose of this study was to identify if any correlation between size of the proximal femoral epiphysis and avascular necrosis (AVN) exists.

METHODS

We retrospectively reviewed 111 patients with developmental dysplasia of the hip treated by closed reduction (124 hips). The diameter and height of both femoral head and ossific nucleus were assessed on preoperative MRI.

RESULTS

The diameter and the height of the femoral head as well as of the ossific nucleus of the contralateral side were significantly greater than the dislocated side. AVN occurred in 21 (16.9%) out of 124 hips. The rate of AVN gradually decreased with age: 30.0% at six to 12 months, 18.2% at 12 to 18 months and 3.7% at 18 to 24 months. Spearman correlation analysis showed that age is negatively correlated with the incidence of AVN (r = -0.274; p = 0.002) and the diameter of the femoral head has a significantly negative association with the incidence of AVN (r = -0.287; p = 0.001). No significant association was observed between the incidence of AVN and height of the femoral head or size of the ossific nucleus. Hips with AVN were significantly smaller than hips without AVN.

CONCLUSIONS

The size of both the femoral head and the ossific nucleus increase with age although the dislocated femoral head is smaller compared with the contralateral side. The diameter of the femoral head and not the size of the ossific nucleus negatively correlate with the risk of AVN, with a bigger femoral head showing lower risk of AVN.

LEVEL OF EVIDENCE

III.

Management of late-detected DDH in children under three years of age: 49 children with follow-up to skeletal maturity

AIMS

When the present study was initiated, we changed the treatment for late-detected developmental dislocation of the hip (DDH) from several weeks of skin traction to markedly shorter traction time. The aim of this prospective study was to evaluate this change, with special emphasis on the rate of stable closed reduction according to patient age, the development of the acetabulum, and the outcome at skeletal maturity.

METHODS

From 1996 to 2005, 49 children (52 hips) were treated for late-detected DDH. Their mean age was 13.3 months (3 to 33) at reduction. Prereduction skin traction was used for a mean of 11 days (0 to 27). Gentle closed reduction under general anaesthesia was attempted in all the hips. Concurrent pelvic osteotomy was not performed. The hips were evaluated at one, three and five years after reduction, at age eight to ten years, and at skeletal maturity. Mean age at the last follow-up was 15.7 years (13 to 21).

RESULTS

Stable closed reduction was obtained in 36 hips (69%). Open reduction was more often necessary in patients ≥ 18 months of age at reduction (50%) compared with those under 18 months (24%). Residual hip dysplasia/subluxation occurred in 12 hips and was significantly associated with avascular necrosis (AVN) and with high acetabular index and low femoral head coverage the first years after reduction. Further surgery, mostly pelvic and femoral osteotomies to correct subluxation, was performed in eight hips (15%). The radiological outcome at skeletal maturity was satisfactory (Severin grades 1 or 2) in 43 hips (83%).

CONCLUSIONS

Gentle closed reduction can be attempted in children up to three years of age, but is likely to be less successful in children aged over 18 months. There is a marked trend to spontaneous improvement of the acetabulum after reduction, even in patients aged over 18 months and therefore simultaneous pelvic osteotomy is not always necessary.

Traction does not decrease failure of reduction and femoral head avascular necrosis in patients aged 6-24 months with developmental dysplasia of the hip treated by closed reduction: a review of 385 patients and meta-analysis

This study aimed to investigate the effects of preliminary traction on the rate of failure of reduction and the incidence of femoral head avascular necrosis (AVN) in patients with late-detected developmental dysplasia of the hip treated by closed reduction. A total of 385 patients (440 hips) treated by closed reduction satisfied the inclusion criteria. Patients were divided in two groups according to treatment modality: a traction group (276 patients) and a no-traction group (109 patients). Tönnis grade, rate of failure reduction, AVN rate, acetabular index, center-edge angle of Wiberg, and Severin's radiographic grade were assessed on plain radiographs, and the results were compared between the two groups of patients. In addition, a meta-analysis was performed based on the existing comparative studies to further evaluate the effect of traction on the incidence of AVN. Tönnis grade in the traction group was significantly higher than in the no-traction group (P = 0.021). The overall rate of failure reduction was 8.2%; no significant difference was found between the traction (9.2%) and no-traction groups (5.6%) (P = 0.203). The rates of failure reduction were similar in all Tönnis grades, regardless of treatment modality (P > 0.05). The rate of AVN in the traction group (14%) was similar to that of the no-traction group (14.5%; P = 0.881). Moreover, the rates of AVN were similar in all Tönnis grades, regardless of treatment modality (P > 0.05). The meta-analysis did not identify any significant difference in the AVN rate whether preliminary traction was used or not (odds ratio = 0.76, P = 0.32). At the last follow-up visit, the two groups of patients had comparable acetabular indices, center-edge angles, and Severin's radiographic grades (P > 0.05). In conclusion, preliminary traction does not decrease the failure of reduction and the incidence of AVN in developmental dysplasia of the hip treated by closed reduction between 6 and 24 months of age.

Developmental Dysplasia of the Hip

Pediatricians are often the first to identify developmental dysplasia of the hip (DDH) and direct subsequent appropriate treatment. The general treatment principle of DDH is to obtain and maintain a concentric reduction of the femoral head in the acetabulum. Achieving this goal can range from less-invasive bracing treatments to more-invasive surgical treatment depending on the age and complexity of the dysplasia. In this review, we summarize the current trends and treatment principles in the diagnosis and treatment of DDH.

Closed reduction and dynamic cast immobilization in patients with developmental dysplasia of the hip between 6 and 24 months of age

BACKGROUND

Closed reduction and spica cast is still the preferred treatment option for children presenting with developmental dysplasia of the hip (DDH) after the age of 6 months. This study aims to investigate the outcomes of patients with DDH treated by closed reduction and dynamic cast immobilization.

METHODS

In total, 159 patients (mean age 15.6 ± 4.2 months; 172 hips) were treated with a dynamic cast immobilization for 3 months, followed by an abduction brace until a stable concentric reduction was achieved. Radiological examination was performed at each follow-up visit to assess reduction, redislocation rate and presence of avascular necrosis (AVN) of the femoral epiphysis. Final radiographic results were evaluated with the Severin classification.

RESULTS

The redislocation rate was 4.1% (7/172); the overall AVN rate was 14.5% (grade II: 16 hips; grade III: 5 hips; grade IV: 3 hips). At last follow-up visit, the mean age of patients was 61.6 ± 21.3 months (range 30.8-141), and the mean acetabular index was 22.6° ± 5.6°; 67.3% of the hips had Severin type I radiographic criteria, 8.5% had type II, 23.6% had type III, and 0.6% had type IV.

CONCLUSIONS

Dynamic cast is an alternative to spica cast immobilization in DDH patients undergoing closed reduction. It has similar redislocation and AVN rates compared to standard spica cast immobilization, as reported by previous studies.

Prereduction traction for the prevention of avascular necrosis before closed reduction for developmental dysplasia of the hip: a meta-analysis

BACKGROUND AND PURPOSE

Avascular necrosis (AVN) is one of the common complications after closed reduction and hip spica cast for developmental dysplasia of the hip (DDH). Prereduction traction has been used to reduce a dislocated hip or decrease the risk of AVN, but there are conflicting results in prevention effects on AVN. The purpose of this study was to systematically review the current literature and evaluate the effect of prereduction traction in preventing AVN in children with DDH treated by closed reduction through a meta-analysis.

MATERIALS AND METHODS

A systematic review of the literature was performed using PubMed and EMBASE with variations of three major terms: 1) hip dislocation; 2) closed reduction; and 3) avascular necrosis. Seven studies that could compare the incidence of AVN between the traction and no-traction group were included. Methodological quality was assessed, a heterogeneity test was done (p=0.008), and the pooled risk ratios were estimated.

RESULTS

The association between traction and AVN was assessed, using data on 683 hips treated by closed reduction. The incidence of AVN in the traction and no-traction groups ranged from 5% to 47.7% and from 0% to 72.7%, respectively. A meta-analysis with a random effects model indicated no significant difference in the incidence of AVN between traction and no-traction groups (p=0.536).

CONCLUSION

There was insufficient evidence to decide the efficacy of prereduction traction before closed reduction in reducing the risk of AVN in patients with DDH in this meta-analysis. To recommend prereduction traction for the prevention of AVN, long-term follow-up studies considering age, severity of dislocation, and appropriate traction method are needed.

Evaluating the role of prereduction hip traction in the management of infants and children with developmental dysplasia of the hip (DDH): protocol for a systematic review and planned meta-analysis

INTRODUCTION

Developmental dysplasia of the hip (DDH) affects 4-6 per 1000 live births in developed countries. Effective treatment to realign the hip is necessary to avoid long-term morbidities and maximise functional outcome. Treatment options depend on patient age but typically involve hip bracing and/or reduction under general anaesthetic. Some centres also employ prereduction hip traction. Historical papers suggest traction reduces risk of avascular necrosis (AVN) femoral head and reduces requirement for open reduction. However, several studies including a large retrospective cohort study, dispute this. We propose to perform the first systematic review and meta-analysis to clarify the value of prereduction hip traction in the management of DDH in children under the age of 3 years by identifying whether it impacts on the rate of successful closed reduction (CR) and risk of AVN.

METHODS AND ANALYSIS

We will search MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials to identify potentially relevant studies. Studies reporting on incidence of successful CR, AVN femoral head and complications associated with prereduction hip traction in children of less than 3 years with DDH will be eligible for inclusion. Only randomised controlled trials, prospective and retrospective case-control and comparative cohort studies will be included in quantitative review. There will be no study design restrictions for inclusion in qualitative review. Following study selection, full-text paper retrieval, data extraction and synthesis, studies will be assessed for risk of bias and heterogeneity. If the included studies are sufficiently homogeneous, then we will perform meta-analysis. A narrative synthesis of the systematic review's results will also be presented.

ETHICS AND DISSEMINATION

Formal ethical approval is not required as primary patient data will not be collected. The systematic review's results will be disseminated through a peer-reviewed publication.

TRIAL REGISTRATION NUMBER

CRD42017064254; Pre-results.

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.