Correlation of postoperative magnetic resonance image measurements with persisting acetabular dysplasia in open reduction of developmental hip dysplasia

Objectives: The aim of this study was to evaluate correlation of post-reduction magnetic resonance imaging (MRI)-based parameters with residual acetabular dysplasia in developmental dysplasia of the hip (DDH) patients who underwent open reduction. Patients and methods: A total of 62 hips of 54 children (5 males, 57 females; mean age: 8.5±3.5 months; range, 0 to 24 months) with a diagnosis of DDH who underwent open reduction between January 2012 and January 2017 were retrospectively analyzed. The acetabular head index (AHI), head coverage index (HCI), sphericity, bony acetabular index (BAI), cartilage acetabular index (CAI), anterior acetabular index (AAI), posterior acetabular index (PAI), abduction angle (AA), and acetabular medial wall thickness were measured by MRI. The correlation between MRI measurements and residual acetabular dysplasia was evaluated. Results: The mean follow-up was 23.7±10.1 (range, 12 to 56) months. The mean age at the final examination was 47.6±10.4 months. The age at the time of operation (r=0.250, p=0.049), medial wall thickness (r=0.304, p=0.016), AAI (r=0.729, p<0.001), PAI (r=0.590, p<0.001), and early postoperative AI (r=0.900, p<0.001) at the third postoperative month were positively correlated with the last follow-up AI. The AHI (r=-0.512, p<0.001), sphericity (r=-0,661, p<0.001), and HCI (r=-0.554, p< 0.001) were negatively correlated with the last follow-up AI. Conclusion: Post-reduction MRI parameters can be used to evaluate correlation with persistent acetabular dysplasia in DDH patients.

Magnetic resonance imaging follow-up can screen for soft tissue changes and evaluate the short-term prognosis of patients with developmental dysplasia of the hip after closed reduction

Background Magnetic resonance imaging (MRI) can show the architecture of the hip joint clearly and has been increasingly used in developmental dysplasia of the hip (DDH) confirmation and follow-up. In this study, MRI was used to observe changes in the hip joints before and after closed reduction (CR) and to explore risk factors of residual acetabular dysplasia (RAD). Methods This is a prospective analysis of unilateral DDH patients with CR and spica cast in our hospital from October 2012 to July 2018. MRI and pelvic plain radiography were performed before and after CR. The labro-chondral complex (LCC) of the hip was divided into four types on MRI images. The variation in the thickening rate of the ligamentum teres, transverse ligaments, and pulvinar during MRI follow-up was analyzed, and the difference in cartilaginous acetabular head index was evaluated. The “complete relocation” rate of the femoral head was analyzed when the cast was changed for the last time, and the necrotic rate of the femoral head was evaluated after 18 months or more after CR. Lastly, the risk factors of RAD were analyzed. Results A total of 63 patients with DDH and CR were included. The LCC was everted before CR and inverted after CR, and the ligamentum teres, transverse ligaments, and pulvinar were hypertrophic before and after CR, and then gradually returned to normal shape. The cartilaginous acetabular head index gradually increased to normal values. Complete relocation was observed in 58.7% of femoral heads, while 8.6% had necrosis. The abnormalities in LCC was related to RAD (OR: 4.35, P = 0.03), and the rate of type 3 LCC in the RAD group was higher. However, the IHDI classification (P = 0.09); the “complete relocation” of femoral heads (P = 0.61); and hypertrophy of the ligamentum teres (P = 1.00), transverse ligaments (P = 1.00), and pulvinar (P = 1.00) were not related to RAD. Conclusions In this study, MRI can observe the variations of the abnormal soft tissue structures of the diseased hips after CR and spica casting, and can evaluate which hips will have RAD after CR. Therefore, we can utilize MRI in DDH patients appropriately.

Dynamic Instability in Young Adults with Symptomatic Hip Dysplasia: Analysis using a Computer-Assisted Image-Matching Procedure

Background: Repeated microtrauma often causes damage to the periarticular soft tissues. This damage, together with the lack of acetabular bony coverage, such as developmental dysplasia of the hip (DDH), can contribute to various degrees of dynamic instability of the hip joint and cause progressive osteoarthritic changesThe purpose of this study was to use an image-matching procedure to compare dynamic instability of the hip joint in patients with DDH who did or did not undergo periacetabular osteotomy (PAO). Methods: Six patients (6 hips) with symptomatic DDH were enrolled. A 6-month trial of nonsurgical management was initiated at the first visit. PAO was performed in 3 patients who experienced persistent pain after conservative treatment. The dynamic instability of all 6 hips was evaluated. Results: Japanese Orthopaedic Association hip scores improved significantly in all hips regardless of PAO. At the first visit, the center-edge angle, Sharp angle, vertical-center-anterior angle, and acetabular head index were not significantly different between the PAO and non-PAO groups. Dynamic instability was defined as the 3D translation of the femoral head center for the acetabular center at hip abduction angles from 0° to 30°. In the non-PAO group, the mean sagittal, axial, and coronal translations were 2.4 mm, 2.2 mm, and 1.1 mm, respectively, and in the PAO group they were 2.4 mm, 7.2 mm, and 2.7 mm, respectively. There was a significant difference in axial translation between the 2 groups. Conclusion:Dynamic instability leads to periarticular soft tissue damage and insufficient bony coverage, and causes progressive osteoarthritic changes. Dynamic instability in the axial plane induces persistent hip pain after nonsurgical management. Affected patients should undergo PAO as soon as possible.

Clinico-radiological correlation during the course and healing of Legg-Calve-Perthes’ disease treated by a non-intensive conservative method

Introduction. The purpose of this study is to signify any clinical and radiological correlation, if present, in patients of Legg-Calve-Perthes’ disease (LCPD) who underwent an ambulatory conservative method of containment and their final outcome. Material and methods. Retrospective study over an 8-year period including patients of LCPD who were treated by an ambulatory conservative method showing signs of healing in the last radiological assessment was done. Clinically, gait, limb length discrepancy, range of motion of the hip, and Harris hip score were noted. The radiological parameters assessed in this study were epiphyseal index, epiphyseal quotient, acetabular head index, and epiphyseal extrusion index. Stulberg criteria was used to assess final outcome. Results. A total of 24 patients (17 males, 7 females) with a mean age of 7.9±3 years (5–9 years) who had a clinic-radiological diagnosis of LCPD were included in the study. There was a significant improvement of range of motion of the hip joint along with Harris hip score (t(18)= -16.77, p<0.001) but no significant changes in the radiological parameters during the course of the disease. There was no correlation between radiological parameters and Harris hip score. 79.1% (19/24) had a good outcome at final follow up. Conclusion. The function and clinical outcome during the course and healing of LCPD does not correlate with the radiographic changes and ambulatory conservative management leads to satisfactory improvement in functional activity. Age at onset and lateral pillar classification are important factors influencing final outcome in LCPD.

Investigation of the priority among the roentgenogram measurements in acetabular dysplasia

Purpose: There are many radiographic parameters to evaluate developmental dysplasia of the hip joint (DDH); however, the priority between the parameters is unclear. We evaluated the priority of radiographic parameters in DDH. Methods: We retrospectively reviewed the radiographs of 82 consecutive patients aged above 85 years without hip osteoarthritis (OA; no osteoarthritis (NO) group), and 28 patients with early stage hip OA were set as the control group (OA group). We used the linear discriminant analysis (LDA) to consider the priority of the following parameters: acetabular roof obliquity (ARO), center-edge (CE) angle, Sharp angle, acetabular head index (AHI), and acetabular depth ratio (ADR). Results: The LDA of five different parameters revealed that the NO and OA groups could be almost distinguished with 83.6% accuracy ( p < 0.0001, Wilks’ lambda test). The standardized scoring coefficients were as follows: ARO, −0.23; CE, −0.43; Sharp, −0.29; AHI, 0.97; and ADR, 0.11. The AHI was particularly noticeable in the NO group. Conclusion: Dissociation of the AHI in the OA group was significantly higher than that of the other parameters in the OA group compared to the parameters in the NO group. A small AHI may be a risk parameter for hip OA due to DDH.

Closed Reduction as Therapeutic Gold Standard for Treatment of Congenital Hip Dislocation

Background Congenital hip dislocation (luxation) has an incidence of 0.4 – 0.7% and is regarded as a prearthrotic deformity. Thus, if not being diagnosed and treated at a very early age, extensive surgical measures are inevitable in childhood and early adulthood. Methods In the time between 01/2013 and 02/2019 we performed 28 600 hips sonographies in babies as part of general screening measures at U2 or U3. There were 71 instable, dysplastic or dislocated hips diagnosed that were treated by arthrographic, closed reduction. After a hip spica cast was applied, reposition was controlled by MRI, estimating the acetabular head index (ACI), the head coverage index (HCI) as well as the femoral headʼs sphericity or by sonography using the Graf method. Results Overall success rate was 91.6% for primary closed reduction. Patients with primarily irreducible hips were significantly older (p < 0.003) than patients with primarily successful reducible hips. Congenital dislocated hips had significantly higher ACIs (p < 0.001) and HCIs (p = 0.03) as well as significantly less well rounded femoral heads (sphericity; p < 0.001) compared to stable hips. Conclusion Early diagnosis and treatment of congenital dislocated hips by closed reduction is essential for a sufficient and regular maturation of the hips without further surgical interventions.

Transpositional Periacetabular Osteotomy with Allografting in Patients with Severe Dysplasia: Mid-Term Results

Aim The purpose of this study was to analyse the extent of surgical correction and the early clinical results obtained using periacetabular osteotomy with allogenic bone grafting in patients with severe acetabular dysplasia. Methods 44 hips in 38 patients were confirmed to have severe acetabular dysplasia and underwent this procedure. The mean follow-up period was 4.2 (range 1.5-8.2) years. Severe acetabular dysplasia was defined as a centre-edge angle less than 0°, an acetabular-head index less than 50% and an acetabular roof obliquity greater than 30°. Periacetabular osteotomy was performed with transpositional osteotomy of the acetabulum. The patients were divided into 2 groups according to the radiographic appearance: 34 hips in the early stage group and 10 hips in the advanced stage group. Postoperatively, the hips were radiographically assessed for dysplasia correction. The clinical results and hip function were measured using the Harris Hip Score. Results The average pre-operative Harris Hip Score improved from 70 to 91 points at the latest follow-up. The average centre-edge angle, acetabular-head index and acetabular roof obliquity improved from −9° to 36°, 41% to 91% and 31° to 2°, respectively. Continuity of the Shenton line improved from 15 to 35 hips. No instances of nonunion or of transported segment collapse were encountered in this series; however, a grafted allogenic bone was absorbed in 1 case. Conclusions The usage of allogenic bone grafting combined with periacetabular osteotomy is an effective technique for treating severe acetabular dysplasia. In this series, the early clinical and radiographic results were excellent.

HIP MORPHOLOGY: COMPARATIVE STUDY BETWEEN EGYPTIANS AND JAPANESE ADULTS

The prevalence of osteoarthritis appears to vary widely among ethinic groups. Many studies had been published describing the acetabular morphology of Chinese, Nigerians, Singaporeans and Japanese. No previous studies comparing Egyptian Arabs and Japanese Orientals work available. Purpose: The aim of this study was to determine the ethnic variations of acetabular morphology between Egyptian and Japanese populations. Patients and Methods: A total of 844 Egyptian and 757 Japanese consecutive patients with no clinical evidence of hip osteoarthritis and who underwent pelvic radiography in the supine position for hip trauma or a routine health check were analyzed for the relationships between the center-edge (CE) angle, Sharp angle, acetabular head index, as well as the relationships of the above-mentioned variables with age, gender, body height. Results: Comparing the measurements of those three parameters in both populations showed statistically significant values (all Egyptian versus Japanese, all female versus male are significant). Conclusion: Our data confirm the presence of ethnic variations in acetabular morphology which predispose to various pathologies of the hip joint.