Comparison of open reduction alone and open reduction plus Dega osteotomy in developmental dysplasia of the hip

Femoral Head Coverage Assessment in Healthy Children Younger than 6 Years

Introduction

Developmental dysplasia of the hip (DDH) is one of the commonest hip joint pathologies in children; to treat it properly, hip surgeons should know the normal femoral head (FH) coverage by the acetabulum. This paper aims to assess the femoral head coverage in healthy children younger than 6 years.

Methods

270 hip joint CT scans were selected, and digital pelvic models were created according to these scans. FH coverage by the five acetabular regions was assessed according to patient's age and sex.

Results

Normal reference values of FH coverage by different acetabular regions were obtained. It was found that the growth process of different acetabular regions occurs nonlinearly with the periods of acceleration. Anterior and superior-anterior acetabular regions grow more intensively in boys up to 3 years old and between 4 and 5 years old both in boys and girls; superior-posterior, posterior-superior, and posterior-inferior acetabular regions grow more intensively in boys and girls up to 3 years old and between 4 and 5 years old (p ≤ 0.005). The following sex differences in FH coverage by the acetabulum were found: more superior-anterior FH coverage was found in boys and posterior FH coverage in girls (p ≤ 0.005).

Acetabular remodeling after graft extrusion, rotation or impaction in Dega and Pemberton acetabuloplasties for developmental dysplasia of the hip

Traditionally graft displacement following Pemberton and Dega acetabuloplasties involves internal fixation for treatment of developmental dysplasia of hip (DDH). This study was performed to assess the acetabular remodeling by conservative management of graft displacement among patients with DDH. This was a retrospective study of 20 patients 17 (85%) women and 3 (15%) men; mean age 22.90 ± 6.96 months with DDH who underwent Pemberton and Dega acetabuloplasties at King Khalid University Hospital, Riyadh between January 2013 and January 2018. All patients after losing acetabular correction during immediate postoperative period were treated by conservative management. The management involved application of Spica cast for 6 weeks that was trimmed to broomstick cast for an extended period of time and finally replaced by nocturnal abduction brace until normal acetabular index (AI) was achieved. The patients were followed up for a mean period of 44.60 ± 12.36 months. Out of the total, 18 (90%) patients with DDH were successfully treated by conservative management. The mean preoperative AI of 43.70° ± 5.91° improved to 21.35o ± 6.32o at the final follow-up (P < 0.001) which was no different when compared to the mean of unaffected hips (19.70o ± 2.96o; P < 0.44). The mean preoperative CEA of all the patients was negative that improved during the conservative treatment to 29.20° ± 10.0° which was no different when compared with the mean of unaffected (31.70° ± 4.64o; P = 0.32) hips at the final follow-up. doption of less aggressive approach for management of displaced, rotated or impacted autograft following acetabuloplasties among children with DDH was not only a useful conservative approach for remodeling of hips but also obviated the need for additional surgical intervention.

Surgical treatment of developmental dysplasia of the hip in children - A monocentric study about 414 hips

INTRODUCTION

No consensus exists about the open reduction of developmental dysplasia of the hip (DDH; age of surgery and the need for additional bone surgery). We report clinical and radiological outcomes of a large monocentric study. The objectives are to analyze outcomes and to give recommendations.

MATERIALS AND METHODS

This was a retrospective review of 414 hips (301 patients) operated on for DDH between 2010 and 2018. The mean age at the time of surgery was 34.6 months (14-96 months). In all, 72 hips had open reduction (OR) alone, 130 had OR with femoral osteotomy, 37 had OR with pelvic osteotomy, and 175 hips OR was associated with femoral and pelvic osteotomy. The mean follow-up was 6.5 years (3-10 years). Clinical outcomes were evaluated according to Mckay's classification. The acetabular index was measured, and Severin classification was used for radiological outcomes. Reduction failure and residual dysplasia were noted, and avascular necrosis of femoral head (AVN) was assessed according to Kalamchi and MacEwen classification.

RESULTS

At the last follow-up, 331 hips (80.2%) had good clinical results, and 319 (77%) had satisfactory radiological results. The AI measured on the last follow-up radiograph was ≤25° in 350 hips. AVN was noted in 83 hips (20%). Redislocation was founded in 53 hips (12%). Overall: 293 hips (72%) had stable reduction without AVN with good clinical and radiological outcomes.

DISCUSSION

Clinical outcomes are better and the risk of AVN decreases significantly when a femoral osteotomy is performed. There were better radiological results when pelvic osteotomy was performed. The rate of residual dysplasia was higher when pelvic osteotomy was not performed. We recommend a femoral shortening osteotomy for high dislocations (Tönnis 3 or 4) for children over 18 months and a pelvic osteotomy for children over 36 months or over 18 months with an acetabular index > 25°.

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

Background

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

Methods

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

Results

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

Conclusions

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

Short-term outcomes of treatment in children presenting with DDH in walking age - An analysis of 84 hips

BACKGROUND

Developmental Dysplasia of Hip (DDH) presenting at walking age is not uncommon, particularly in developing countries. The available treatment modalities in this age group are closed reduction (CR), open reduction (OR), OR with additional femoral and/or pelvic osteotomy. This study was done in patients who presented between 12 and 36 months of age to assess the following: 1) Percentage of hips amenable for successful CR, 2) failure rate after CR and OR in walking age DDH and 3) the need for secondary procedures to address subluxation and residual dysplasia within first 2 years.

METHOD

ology: After IRB approval, the institutional database was searched for patients admitted with a diagnosis of DDH from January 2009 to January 2019. We identified 142 patients, of which 65 patients with 84 hips formed the study cohort after applying inclusion and exclusion criteria. Demographic details, details of the interventions, brace wear, revision procedures and radiological data were collected from Hospital Information System. We divided the patients in three groups: Group I - CR, Group II -OR, and Group III - OR with an additional bony procedure in the form of femoral and/or pelvic osteotomy.

RESULTS

The mean age at presentation was 20.1 months. We had 10 (11.9%) hips in group I, 39 (46.4%) hips in group II and 35 (41.6%) hips in group III. The mean follow-up was 44.8 months (24-132 months). In Group I, 5 (50%) had re-dislocation and 2 (20%) needed revision intervention for residual dysplasia. In Group II, 4 (10%) had re-dislocation and 4 (10%) needed revision intervention. In Group III, 5 (14.2%) hips needed revision intervention for residual dysplasia. The mean final AI was 24.6°in Group I, 28.2° in Group II and 26.3°in Group III. There was no significant difference in the final AI between the groups (p > 0.05).

CONCLUSIONS

An attempted closed reduction has a 50% failure rate, and we recommend a low threshold for open reduction. There is a 10% rate of re-dislocation following open reduction with or without additional bony procedure. About 50% of the dysplastic hips treated without pelvic osteotomy at the time of index procedure fail to remodel and have residual acetabular dysplasia.

Salter osteotomy without open reduction in the Tönnis type II developmental hip dysplasia: A retrospective clinical study

PURPOSE

We aimed to evaluate the clinical and radiological outcomes of children older than 18 months who were treated with Salter osteotomy without open reduction for Tönnis type II hip dysplasia.

METHODS

Thirty-two type II hips of 24 patients were included in the study. The mean age was 43.22 (18-108) months. The mean follow-up period was 50 (24-142) months. Seven patients had left sided, nine had right sided, and eight had bilateral developmental dysplasia of the hip. All patients underwent closed reduction and Salter osteotomy. Preoperative and postoperative radiographs were assessed by measuring the center-edge (CE) angle of Wiberg, Smith's c/b and h/b ratio, and acetabular index (AI). Patients were evaluated clinically according to McKay's criteria and radiologically according to Severin criteria. The Kalamchi and MacEwen criteria were used in the evaluation of avascular necrosis.

RESULTS

The mean preoperative AI, CE angle, c/b, and h/b ratio were 36.7° (±4.1), 7.2° (±5.9), 0.9 (±0.08), and 0.05 (±0.04), respectively. The mean latest follow-up AI, CE angle, c/b, and h/b ratio were 18.2° (±1.7), 38.8° (±5.4), 0.6 (±0.03), and 0.19 (±0.04), respectively. The comparison of preoperative and postoperative radiological values revealed statistically significant improvement ( p < 0.01). On the latest physical examinations of the patients, 25 (78.1%) hips were rated excellent, and 7 (21.9%) were rated good according to the McKay criteria. The Severin classification determined 25 (78.1%) hips were grade I and 7 (21.9%) hips were grade II. Type I avascular necrosis (AVN) was seen in four (12.5%) hips. Three of these four hips were more superolateral in preoperative radiographs (c/b > 1 and h/b < 0.05).

CONCLUSIONS

Salter osteotomy without open reduction is a good surgery option for Tönnis type II hip dysplasia, in which closed reduction can be performed. However, the risk of AVN should be kept in mind in more superolateral type 2 hips.

Comparison of Open Reduction Alone and Open Reduction Plus Pemberton Osteotomy Techniques in the Treatment of Developmental Hip Dysplasia at Walking Age

Objective

Open reduction (OR) alone and OR plus Pemberton periacetabular osteotomy (PPO) techniques are commonly used in the treatment of developmental dysplasia of the hip at walking age. However, discussions on the timing of acetabular osteotomy are still ongoing. The aim of the present study was to compare the results of patients who underwent Ferguson OR (FOR group) and OR plus PPO group.

Materials and Methods

Between 2008 and 2017, we performed surgery on the hips, which we thought were used for closed reduction but could not be reduced as closed, or that the reduction was not stable. Patient follow-up was ≥12 months. The study included 75 hips of 57 patients of which 20 (26.7%) patients with FOR and 55 (73.3%) patients with PPO. Preoperative and postoperative acetabular indices (AIs), additional surgical intervention rates, and avascular necrosis (AVN) rates were compared. The Kalamchi-McEwen classification system was used to evaluate AVN.

Results

The average age of the patients was 12.38 (9-14) months. The mean follow-up period was 38.95 (12-140) months. AVN developed in 21 (24%) hips (6 (8%) type 1, 13 (17.3%) type 2, and 2 (2.7%) type 3). AVN developed in 7 (35%) hips in the FOR group and 14 (25.5%) hips in the PPO group. No statistically significant difference was found between the two groups (p=0.416). Revision surgery was performed in 2 (3.7%) cases of the PPO group and 6 (31.5%) cases of the FOR group. Statistically, the PPO group had less revision surgery (p=0.004). The PPO group had an AI of 13.33° (5°-27°) that was significantly lower (p<0.001) than that of 27.98° (18.39°) of the FOR group.

Conclusion

Ferguson and Pemberton techniques are current and effective in the treatment of patients with developmental hip dysplasia at walking age. There was no significant difference between the two groups when examined from the point of view of AVN, but the results of PPO surgery were found to be better with respect to AI and revision surgery.

Use of iliac crest allograft for Dega pelvic osteotomy in patients with cerebral palsy

Background

Dega pelvic osteotomy is commonly performed procedure in patients with cerebral palsy (CP) undergoing hip reconstructive surgery for hip displacement. However, there has been no study investigating the outcomes after Dega pelvic osteotomy using allograft in patients with CP. This study investigated the outcomes of Dega pelvic osteotomy using iliac crest allograft in CP with hip displacement and the factors affecting allograft incorporation.

Methods

This study included 110 patients (150 hips; mean age 8y7mo; 68 males, 42 females) who underwent hip reconstructive surgeries including Dega pelvic osteotomy using iliac crest allograft. To evaluate the time of allograft incorporation, Goldberg score was evaluated according to the follow-up period on all postoperative hip radiographs. The acetabular index, migration percentage, and neck-shaft angle were also measured on the preoperative and postoperative follow-up radiographs.

Results

The mean estimated time for allograft incorporation (Goldberg score ≥ 6) was 1.1 years postoperatively. All hips showed radiographic union at the final follow-up and there was no case of graft-related complications. Patients with Gross Motor Function Classification System (GMFCS) level V had 6.9 times higher risk of radiographic delayed union than those with GMFCS level III and IV. Acetabular index did not increase during the follow-up period (p = 0.316).

Conclusions

Dega pelvic osteotomy using iliac crest allograft was effective in correcting acetabular dysplasia, without graft-related complications in patients with CP. Furthermore, the correction of acetabular dysplasia remained stable during the follow-up period.

Duration of immobilization after developmental dysplasia of the hip and open reduction surgery

BACKGROUND

There is no consensus about the duration of post-operative immobilization in the treatment of DDH (developmental dysplasia of hip). Our aim in this study is to compare between two post-operative immobilization protocols for patients undergoing open reduction.

MATERIALS AND METHODS

Thirty-eight hips in 32 patients assigned to group A were immobilized in hip spica for four weeks followed by abduction brace application which was gradually weaned through the periods of several months and 29 hips in 24 patients assigned to group B immobilized in hip spica for 12 weeks without further bracing. Both groups were surgically reduced using anterior approach between the ages of 12-24 months.

RESULTS

There were non-significant statistical difference between both groups as regards clinical and radiological outcome but there is significant statistical difference as regards AVN (avascular necrosis) on follow-up between both groups. The rate of AVN cannot be related to the method of immobilization, as there are many factors can lead to AVN of the hip as immobilization in an extreme position and tight reduction.

CONCLUSION

Group A post-operative immobilization protocol is safer and associated with less complications and more comfortable to the patient and parents than that used in group B. Early removal of hip spica cast and application of hip abduction brace does not increase the rate of re-dislocation.

LEVEL OF EVIDENCE

Level III Retrospective comparative study.

The early radiological effects of Dega and Pemberton osteotomies on hip development in children aged 4-8 years with developmental dysplasia of the hip

We aimed to investigate the early radiological effects of Dega and Pemberton iliac osteotomies that were performed in patients aged 4-8 years with developmental dysplasia of the hip on development of hip joint. Dega osteotomy or Pemberton osteotomy was performed in 76 hips of 58 patients because of developmental dysplasia of the hip between September 2011 and June 2015 and were evaluated retrospectively. Of a total of 76 hips, Pemberton osteotomy was performed on 39 (19 unilateral) and Dega osteotomy was performed on 37 (21 unilateral). In all hips, the acetabular index, acetabular depth ratio, centre-edge angle of Wiberg, and Reimer's index values were recorded preoperatively and at the final follow-up. We measured the surface areas of the femoral head ossific nucleus in patients with unilateral dysplastic hips and compared results before both osteotomy procedures and at the final follow-up. There were no statistically significant differences between the groups in terms of the acetabular index and acetabular depth ratio values (P>0.05) preoperatively and at the final follow-up, but the mean centre-edge angle of Wiberg and Reimer's index values showed significant statistical differences in favor of the Dega procedure (P<0.05). There was a statistically significant difference in favor of the Pemberton procedure when the mean ratio of the surface area of the femoral head ossific nucleus on the dysplastic side in relation to the normal side was compared preoperatively (P=0.042) and at the final follow-up (P=0.027) in unilateral hips. Although Dega and Pemberton osteotomies produce satisfactory radiological outcomes at early stages in children aged 4-8 years with developmental dysplasia of the hip, a higher rate in the surface area of the femoral head ossific nucleus was observed in the Pemberton osteotomy group, which also had a lower mean age than the Dega osteotomy group.