Developmental Dysplasia Of The Hip Group Research Articles

Specific pelvic shape in patients with developmental dysplasia of the hip on 3D morphometric homologous model analysis.

To clarify the morphological factors of the pelvis in patients with developmental dysplasia of the hip (DDH), three-dimensional (3D) pelvic morphology was analyzed using a template-fitting technique. Three-dimensional pelvic data of 50 patients with DDH (DDH group) and 3D pelvic data of 50 patients without obvious pelvic deformity (Normal group) were used. All patients were female. A template model was created by averaging the normal pelvises into a symmetrical and isotropic mesh. Next, 100 homologous models were generated by fitting the pelvic data of each group of patients to the template model. Principal component analysis was performed on the coordinates of each vertex (15,235 vertices) of the pelvic homologous model. In addition, a receiver-operating characteristic (ROC) curve was calculated from the sensitivity of DDH positivity for each principal component, and principal components for which the area under the curve was significantly large were extracted (p<0.05). Finally, which components of the pelvic morphology frequently seen in DDH patients are related to these extracted principal components was evaluated. The first, third, and sixth principal components showed significantly larger areas under the ROC curves. The morphology indicated by the first principal component was associated with a decrease in coxal inclination in both the coronal and horizontal planes. The third principal component was related to the sacral inclination in the sagittal plane. The sixth principal component was associated with narrowing of the superior part of the pelvis. The most important factor in the difference between normal and DDH pelvises was the change in the coxal angle in both the coronal and horizontal planes. That is, in the anterior and superior views, the normal pelvis is a triangle, whereas in DDH, it was more like a quadrilateral.

The usefulness of universal ultrasound before hospital discharge for early diagnosing hip dysplasia in Korean neonates with breech presentation in a single center: A retrospective study.

Developmental dysplasia of the hip (DDH) is a broad-spectrum disorder. Early diagnosis and treatment are important for improved prognosis and a lower risk of long-term complications. Selecting high-risk infants is important for the early diagnosis of DDH using ultrasonography; however, there are no standard international guidelines. This study aimed to identify the usefulness of universal ultrasound before hospital discharge in breech-born neonates and proposes selective ultrasound for high-risk patients. A retrospective chart review was conducted to identify breech-born neonates who underwent hip ultrasonography before discharge for the detection of DDH between 2019 and 2023. Patients were categorized into DDH and non-DDH groups according to the ultrasound results. We compared sex, gestational age, birth weight, first-born status, twin pregnancy, associated anomalies, presence of symptoms, physical examination results, and timing of the first hip ultrasound. The medical records of the mothers were reviewed to identify the amount of amniotic fluid and duration of breech presentation. This study included 102 patients, of whom 62 and 40 were assigned to the non-DDH and DDH groups, respectively. Congenital anomalies, positive symptoms, and positive physical examination results were significant risk factors. However, female sex, first-born status, and oligohydramnios were not statistically significant. The duration of breech presentation during pregnancy was not significant. Additionally, the risk of Pavlik harnesses was higher in patients who underwent a positive physical examination. Universal ultrasonography before discharge is not recommended for the early diagnosis of DDH in all breech-born neonates because of the high rate of overdiagnosis. We recommend that ultrasonography be performed in patients with congenital anomalies, except for foot problems, or in those with a positive physical examination conducted by trained specialists.

Does cranial bone ossification differ in children with developmental dysplasia of the hip?

This study aims to compare cranial bone ossification between patients with developmental dysplasia of the hip (DDH) and healthy individuals. Between September 2021 and April 2022, a total of 60 healthy female individuals (median age: 24.5 months; range, 18 to 36 months) and 56 female DDH patients (median age: 23 months; range, 18 to 35 months) were included. Age, head circumference, weight, height, and patency of the anterior fontanel were measured in groups. Percentiles were classified as very low, low, normal, high and very high. All patients were female and those with abnormal thyroid function test, vitamin D, calcium, phosphate and alkaline phosphatase values were not included in the study. For those diagnosed with DDH, they were included in the group regardless of the type of treatment. No statistically significant difference was found between the groups in terms of age and weight (p>0.05). The very low and very high head circumferences were more frequent, and the normal head circumferences were less frequent in the DDH group (p<0.05). There was no significant difference between groups in terms of fontanel closure (p>0.05). In open fontanels, no significant difference was found in both groups in terms of age (p>0.05). Our study results showed no significant difference between the fontanel ossifications of children with and without DDH; however, we found that the ossification of the skull bones of children with DDH was different compared to healthy children.

Femurs in patients with hip dysplasia have fundamental shape differences compared with cam femoroacetabular impingement

ABSTRACT Femoral deformities are common in developmental dysplasia of the hip (DDH), but decisions about how to treat them are not standardized. Of interest are deformities that may be akin to cam femoroacetabular impingement (FAI). We used three-dimensional and two-dimensional measures to clarify the similarities and differences in proximal femur shape variation among female patients with DDH (n = 68) or cam FAI (n = 60). Three-dimensional measures included femoral head asphericity, as well as shape variation using statistical shape modeling and principal component analysis (PCA). Two-dimensional measures included the α-angle, head–neck offset (HNO) and the neck–shaft angle (NSA). Significant shape variations were captured in the first five PCA modes, with the greatest shared variation between groups being the length from the lesser trochanter to the femoral head and greater trochanter height. Variations unique to DDH were irregularities at different areas of the femoral head, but not at the lateral femoral head–neck junction where variation was strong in FAI. The FAI group also had unique variations in greater trochanter shape. DDH femoral heads were less spherical, as indicated by larger sphere-fitting errors (P &amp;lt; 0.001). Radiographically, the DDH group had significantly smaller α-angles (P &amp;lt; 0.001), larger head–neck offsets (P = 0.02) and larger NSAs (P &amp;lt; 0.001). Both the articular and extra-articular regions of the proximal femur have distinct shape features in DDH and cam FAI that can uniquely affect the biomechanics of each disorder. Accordingly, approaches to addressing each disorder should be unique.

A Novel Method for Assessing the 3-dimensional Morphology of Cartilaginous Acetabulum Via Childhood Magnetic Resonance Imaging.

Periarticular cartilage is abundant in children, making evaluations of 3-dimensional (D) cartilaginous acetabular morphology using x-ray or computed tomography (CT) difficult. The study aimed to visualize the 3D cartilaginous acetabular morphology in normal children and patients with pediatric developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) of 17 female children without acetabular dysplasia at 7.5 years and CT of 33 normal female adolescents with mature bones at 14.6 years were used as controls. Subjects were 26 female patients with unilateral DDH who underwent angulated Salter innominate osteotomy (A-SIO) at 5.5 years. Preoperative and postoperative MRIs were performed at 5.2 and 7.0 years, respectively. The MRI sequence was 3D-MEDIC. The medial intersection (point A) of the line connecting the centers of the bilateral femoral head and the femoral head were defined as point zero. The 3D coordinates (X, Y, Z) of the cartilaginous acetabular edge (point C) from anterior to posterior were calculated. Subsequently, a 3D scatter plot was created using 3D graph software. The subjects were divided into 6 groups, including control MRI, control CT, unaffected DDH before and after A-SIO, and affected DDH before and after A-SIO. The femoral head coverage ratio (FHCR: AC/AB) was used to quantify coverage and was compared in each group. In the control MRI group, the acetabular coverage was small anteriorly, largest anterolaterally, and gradually decreased posteriorly, similar to the bony acetabulum in adolescents. In the affected DDH before A-SIO group, the coverage was significantly lower than that of the control MRI and unaffected DDH groups. After A-SIO, the morphology improved beyond the unaffected DDH and the control MRI group. The global defect of the cartilaginous acetabulum in the affected DDH group was significantly improved to normal morphology after A-SIO. Evaluating the cartilaginous acetabulum using MRI was useful for assessing hip morphology in childhood. Level III-retrospective comparative study.

Relationships among hip instability, iliofemoral ligament, and pain in patients with developmental dysplasia of the hip

BackgroundTo evaluate the relationships among hip instability, pain, and morphology of the iliofemoral ligament (ILFL) in patients with developmental dysplasia of the hip (DDH) using ultrasonography (US). MethodsWe reviewed 86 patients (109 hips) with DDH (Group D), 40 patients (46 hips) with borderline hip dysplasia (BDDH) (Group B) and 20 patients (23 hips) without hip pain and bony abnormality (control group). Group D was classified into three subgroups—the severe (group SP), moderate (group MP), and none/mild (group NMP) hip pain groups—using the visual analogue scale (VAS). For evaluating hip instability and ILFL morphology, the distance between the anterior edge of the anterior inferior iliac spine (AIIS) and the horizontal line to the femoral head, and ILFL thickness were measured using US. The difference between the distance in the neutral position and Patrick position was calculated and defined as the femoral head translation distance (FTD). ResultsFTD and ILFL thickness in group D were significantly larger than those in the control group and group B (P < 0.05). There was a significant positive correlation between FTD and ILFL thickness in three groups (r = 0.57, P < 0.05; r = 0.55, P < 0.05; r = 0.62, P < 0.05, respectively). FTD and ILFL thickness in group SP were significantly larger than those in group NMP (P < 0.05). FTD and ILFL thickness in group D had significantly negative correlations with the lateral center edge (r = −0.54, P < 0.05; r = −0.40, P < 0.05, respectively) and vertical-center-anterior angle (r = −0.51, P < 0.05; r = −0.43, P < 0.05, respectively). ConclusionsAcetabular bony deficiency, especially in the anterior and lateral region can result in antero-posterior hip instability, leading to thickened ILFL and hip pain, even in patients with BDDH. These findings may facilitate our understanding and treatment of patients with DDH. When hip instability is suspected, hip US examination may help confirm the diagnosis and assist in providing objective clinical diagnostic evidence.

An Explorative Study into the Aetiology of Developmental Dysplasia of the Hip Using Targeted Urine Metabolomics

Developmental dysplasia of the hip (DDH) is the most prevalent congenital musculoskeletal disorder, yet its cause remains unknown. Adequate nutrient provision and coordinated electron exchange (redox) processes are critical for foetal growth and tissue development. This novel study sought to explore specific biochemical pathways in skeletal development for potential involvement in the aetiology of DDH. Spot urine samples were collected from infants, aged 13-61 days, with and without DDH. Ion chromatography-mass spectrometry was used to quantify thiosulphate, sulphate, nitrate, and phosphate, whilst nitrite was quantified using high-performance liquid chromato-graphy. Thiobarbituric acid reactive substances (TBARS) were measured as markers of lipid peroxidation. Creatinine and osmolality were determined by a 96-well plate assay and micro-osmometer to potentially normalise values for renal function, lean body mass, and hydration status. Urine samples were analysed from 99 babies: 30 with DDH and 69 age-matched non-DDH controls. Thiosulphate, TBARS, and creatinine concentrations differed between the DDH group and the controls (p = 0.025, 0.015, and 0.004 respectively). Urine osmolality was significantly lower in DDH compared to the controls (p = 0.036), indicative of the production of a more diluted urine in DDH infants. Following adjustment for osmolality, significant differences became apparent in urinary sulphate levels in DDH (p = 0.035) whereas all other parameters were similar between the groups. This is the first study to assess the potential role of these inorganic anions in DDH. The higher levels of sulphate found in infants with DDH suggests either enhanced intake from milk, increased endogenous formation, or impaired renal reabsorption. This investigation demonstrates the power of urine metabolomics and highlights the importance of normalisation for hydration status to disentangle developmental disorders. Our results strongly suggest that DDH is a systemic disease associated with altered uptake, formation, or handling of sulphate. There is potential for new opportunities in the prevention or treatment of DDH via nutritional intervention.

Femoral head translation in borderline and definite dysplastic hips during weight-bearing: 2D/3D image registration analysis

PurposeThe aims of this study were to 1) assess femoral head translation during weight-bearing in symptomatic developmental dysplasia of the hip (DDH) and 2) compare it between borderline DDH and definite DDH.MethodsThe study included four individuals with borderline DDH and nine with definite DDH, scheduled for periacetabular osteotomy. Anteroposterior X-ray images of the hip joint were obtained in the standing position, and computed tomography images of the pelvis were obtained in the supine position. Femoral head translation from the supine to a standing position was measured using 2D/3D X-ray image registration.ResultsFrom a supine to a standing position, the femoral head translated 0.3 mm laterally, 0.5 mm anteriorly, and 0.5 mm superiorly on average. The mean femoral head translation in 3D between the supine and standing positions was 1.5 mm. The 3D femoral head translation in the borderline DDH group was significantly greater than that in the definite DDH group. In the definite DDH group, there was a significant correlation between the center edge (CE) angle and 3D femoral head translation (ρ = -0.78, P = 0.012).ConclusionsSymptomatic DDH showed femoral head translation in the anterior, lateral, and superior directions during weight-bearing. In definite DDH, the amount of femoral head translation was negatively correlated with the CE angle. The amount of 3D translation in patients with borderline DDH was larger than that in definite DDH. Dynamic joint instability during weight-bearing was observed in borderline DDH as well as definite DDH. Treatment to enhance joint stability during weight-bearing is important in both cases.

Coronal and sagittal spinopelvic alignment in the patients with unilateral developmental dysplasia of the hip: a prospective study

BackgroundHow the hip dysplasia affects the spinopelvic alignment in developmental dysplasia of the hip (DDH) patients is unclear, but it is an essential part for the management of this disease. This study aimed to investigate the coronal and sagittal spinopelvic alignment and the correlations between the spinopelvic parameters and the extent of hip dysplasia or the low back pain in unilateral DDH patients.MethodsFrom September 2016 to March 2021, 22 unilateral patients were enrolled in the DDH group with an average age of 43.6 years and 20 recruited healthy volunteers were assigned to the control group with an average age of 41.4 years. The Cobb angle, seventh cervical vertebra plumbline–central sacral vertical line (C7PL–CSVL), third lumbar vertebra inclination angle (L3IA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK) and lumbar lordosis (LL) were measured on the standing anteroposterior and lateral full-length standing spine radiographs. Additionally, the Oswestry Disability Index (ODI) and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) were used to assess the degree of low back pain.ResultsCobb angle (8.68 ± 6.21° vs. 2.31 ± 0.12°), L3IA (4.80 ± 5.47° vs. 0.83 ± 0.51°), C7PL–CSVL (1.65 ± 1.57 cm vs. 0.48 ± 0.33 cm), PT (15.02 ± 9.55° vs. 9.99 ± 2.97°) and TLK (7.69 ± 6.66° vs. 3.54 ± 1.63°) were significantly larger in DDH patients, whereas LL (37.41 ± 17.17° vs. 48.79 ± 7.75°) was significantly smaller (P < 0.05). No correlation was found between significantly different spinopelvic parameters and the extent of dysplasia. Statistical analysis revealed correlations between ODI and Cobb angle (r = 0.59, P < 0.01), PT (r = 0.49, P = 0.02), TK (r = −0.46, P = 0.03) and TLK (r = 0.44, P = 0.04). Correlations between JOABPQE score and the Cobb angle (r = −0.44, P = 0.04), L3IA (r = −0.53, P = 0.01), PT (r = −0.44, P = 0.04), and TK (r = 0.46, P = 0.03) were also observed.ConclusionsCobb angle, L3IA, C7PL–CSVL in coronal plane and PT, TLK in sagittal plane increased, while LL decreased in unilateral DDH patients. These significantly different spinopelvic parameters have no correlation with the extent of dysplasia. Changes in coronal and sagittal plane including Cobb angle, L3IA, PT, TK and TLK were associated with the low back pain in the patients with unilateral DDH.

Characteristics of surface electromyogram signals after Pemberton pelvic osteotomy combined with femoral osteotomy in children with unilateral developmental dysplasia of the hip.

This study aimed to assess the surface electromyogram (sEMG) signal characteristics of the muscle around the hip joint after Pemberton osteotomy in children with unilateral developmental dysplasia of the hip (DDH). A total of 21 children with unilateral DDH who had received Pemberton osteotomy were selected as the DDH group, and 21 healthy children of the same age were selected as the control group. The children in both groups were tested using sEMG, the Root mean square (RMS) values of the tensor fascia lata, rectus femurs, and medial head of the hamstring and gluteus maximum on both sides in standing and walking status were recorded. The value on the affected side in the DDH group was compared with the value on the healthy side himself and the value in the control group. The mean postoperative follow-up in the DDH group was 27.76 ± 24.30 months. The RMS value of the affected gluteus maximum muscle in the DDH group was significantly larger while standing (P < 0.05), the RMS value of bilateral tensor fascia lata muscle was significantly larger while walking (P < 0.05), and the RMS value of the affected hamstring muscle medial head was significantly less in the DDH group compared with the control group (P < 0.05). An asymmetry and compensatory increase in the sEMG activity of the muscles around the hip joint when standing and walking was noted in children with unilateral DDH who underwent Pemberton osteotomy combined with a femoral osteotomy. The rehabilitation training of the muscles around the hip joint after unilateral DDH should be strengthened.

A New Parameter of Hip Instability in Developmental Dysplasia of the Hip (DDH): Teardrop Distance.

BackgroundHip instability is one of the etiologies of accelerated onset of osteoarthritis in developmental dysplasia of the hip (DDH). There are some radiological parameters for hip instability in hip dysplasia like broken shenton’s line, elevated acetabular index, reduced lateral center edge angle (LCEA), upsloping lateral sourcil. We have discovered a new index of teardrop distance (TD) for assessing instability. Herein, we hypothesized that increased TD could be used as evidence of hip instability in DDH patients, which we verified using TD as an auxiliary diagnostic parameter for DDH, from supine to standing position.MethodsFemale DDH patients undergoing Bernese periacetabular osteotomy (PAO) were enrolled in the DDH group, and normal female volunteers were in the control group. Anteroposterior radiographs of the pelvis in the supine and standing positions were taken, and LCEA, Tönnis angle (TA), sharp angle (SA), and TD were tested using Stata software to analyze the changes between supine and standing anteroposterior pelvic radiographs.ResultsThere were 26 female volunteers with 52 hips in the control group: supine TD 6.80 ± 0.98 mm, standing TD 6.65 ± 1.3 mm (P > 0.05). A total of 78 patients with 135 hips were included in the DDH group: supine TD 10.51 ± 3.50 mm, standing TD 10.93 ± 4.23 mm (P < 0.05). In either supine or standing position, TD in the DDH group was significantly wider than that in the control group (P < 0.05). In the DDH group, TD was correlated with TA and LCEA (rp 0.494–0.588, P < 0.05); TD was not correlated with SA, weight, or BMI (P > 0.05). There was a weak correlation between TD difference and standing LCEA (rp −0.276, P < 0.05).ConclusionTD > 10 mm was a common imaging feature of DDH. It increased from supine to standing position, thus indicating hip instability in DDH patients. The hip parameters of both positions should be compared, fully considering the factors of hip stability.

Role of magnetic resonance imaging in assessment of acetabular and femoral version in developmental dysplasia of the hip.

To evaluate the role of magnetic resonance imaging (MRI) in the assessment of femoral and acetabular version in developmental dysplasia of the hip (DDH). This was a cross-sectional study of 20 consecutive patients with DDH (27 dysplastic hips) who were examined with MRI. In dysplastic and normal hips (DDH and comparison groups, respectively), we evaluated the following parameters: osseous acetabular anteversion (OAA); cartilaginous acetabular anteversion (CAA); femoral anteversion; osseous Mckibbin index (OMI); cartilaginous Mckibbin index (CMI); and the thickness of the anterior and posterior acetabular cartilage. The OAA was significantly greater in the dysplastic hips. The CAA, femoral anteversion, OMI, and CMI did not differ significantly between the normal and dysplastic hips. In the DDH and comparison groups, the OAA was significantly lower than the CAA, the OMI was significantly lower than the CMI, and the posterior acetabular cartilage was significantly thicker than the anterior cartilage. Our findings confirm that MRI is a valuable tool for the assessment of femoral and acetabular version in DDH. Preoperative MRI evaluation has great potential to improve the planning of pelvic and femoral osteotomies.

Characteristics of the patellofemoral joint of patients with DDH and the effects of Bernese periacetabular osteotomy on the patellofemoral joint

BackgroundSome patients with developmental dysplasia of the hip (DDH) complained of anterior knee pain (AKP) before and after Bernese periacetabular osteotomy (PAO) surgery. The purpose of this study was to (1) identify the characteristics of patellofemoral joint (PFJ) deformities in patients with DDH and (2) to determine the effects of PAO on the PFJ.MethodsSeventy patients (86 hips) were included in the DDH group. Thirty-three patients (33 knees) without AKP and hip pain were included in the control group. All patients underwent simultaneous CT scans of the hip and knee joints before PAO and after hardware removal surgery. The distance from the anterior inferior iliac spine to the ilioischial line (DAI), was measured in DDH patients. Imaging parameters of knees, including the sulcus angle (SA), femoral trochlear depth (FTD), patellar width (PW), tibial tuberosity-trochlear groove (TT-TG), patellar tilt angle (PTA) and lateral shift of the patella (LSP) were measured in patients in both the DDH and control group. TT-TG, PTA, and LSP of DDH patients were measured before PAO and after hardware removal. The DAI, PTA, LSP and TT-TG of all DDH patients before and after Bernese PAO were compared using paired t-tests. The FTD, PW, and SA of the DDH patients and the control group were analyzed using independent t-tests. PTA, TT-TG, and LSP between the control group and preoperative DDH patients, between the control group and post PAO patients were compared using independent t-tests.ResultsThe DAI changed from 4.04 ± 0.61 mm before PAO surgery to 5.44 ± 0.63 mm after PAO surgery. The SA of the DDH group (140.69 ± 11.30 degree) was greater than that of the control group (130.82 ± 6.43 degree). The FTD and the PW of the DDH group (5.45 ± 1.59 mm, 4.16 ± 0.36 mm) were smaller than that of the control group (7.39 ± 1.20 mm, 4.24 ± 0.38 mm). The changes in LSP, PTA, and TT-TG before and after surgery were not statistically significant. Both before and after PAO, there was no statistically significant difference in the parameters of LSP, PTA, and TT-TG compared with the control group.ConclusionThe knee joints of DDH patients presented a certain degree of femur trochlear groove dysplasia and patellofemoral instability. PAO surgery did not change PFJ stability, although the origination point of the rectus femoris muscle moved laterally during PAO surgery.

A Long-Term Study of Alignment Correction Following Proximal Femoral Varus Osteotomy and Pemberton Osteotomy in Children With Legg-Calvé-Perthes Disease and Developmental Dysplasia of the Hip.

Proximal femoral varus osteotomy (PFVO) is a common procedure performed in children with developmental dysplasia of the hip (DDH) and Legg–Calvé–Perthes disease (LCPD). However, the long-term effect on angular deformities of the knees and ankles following PFVO remains controversial. This study investigated the relationship between PFVO and alignment changes in the knee and ankle after the procedure. Twenty-five patients undergoing PFVO procedure with a minimum 4-year evaluation period were enrolled in the study, including 14 unilateral LCPD and 11 unilateral DDH. The standing scanogram examinations were collected before the operation, immediately following surgery, after a 1-year follow-up, after a 3-year follow-up, and at the final visit to the clinic. The radiographic parameters included leg length, femoral neck-shaft angle (FNSA), femorotibial angle (FTA), mechanical axis deviation (MAD), tibiotalar angle (TTA), and mechanical lateral distal femoral angle (mLDFA). At the final examination, FNSA demonstrated insignificant change between the operative and non-operative limbs in the DDH group. Compared with the postoperative result, FNSA significantly improved in the LCPD group (p = 0.039). Both groups did not develop statistical significance in TTA, mLDFA, MAD, and leg length discrepancy after more than a 5-year follow-up. From a biomechanical perspective that the foot passes more medial to the knee under the center of leg mass, varus knee was prone to develop. In order to correct the mechanical axis, the knee reverted to a valgus position gradually. Our study indicates that patients with LCPD or DDH receiving PFVO and Pemberton osteotomy narrow the gap of angular growth in knees and ankles between the operative and non-operative limbs after a long-term follow-up.

Early Emergent and Progressive Aberrant Subchondral Bone Remodeling Coupled with Aggravated Cartilage Degeneration in Developmental Dysplasia of the Hip.

ObjectiveDevelopmental dysplasia of the hip (DDH) is the most common skeletal development in children and could result in secondary osteoarthritis. This study aims to clarify the alternations of subchondral trabecular bone remodeling and microstructural properties during the development of DDH, and the potential influence of these alternations on the overlying cartilage degeneration and DDH progression.DesignTraditional straight-leg swaddling method was adopted to establish DDH model in newborn Sprague Dawley rats. Hip joint specimens from normal or DDH rats were used. Typical features of DDH in radiological examination were observed by x-ray analysis. Micro–computed tomography analysis was applied to evaluate the microstructural properties of subchondral bone at postnatal weeks 2, 4, and 6. Histological and immunohistochemical analyses were adopted to appraise subchondral bone remodeling activity and cartilage degeneration. The associations among subchondral bone, articular cartilage, and DDH severity were analyzed via multiple linear regression analysis.ResultsCompared with control group, the subchondral bone in DDH group displayed a gradual trend of deteriorated microstructure and worsening biomechanical properties along with aberrant bone remodeling, which might be responsible for the inhibition of stress transmission from the articular cartilage to the subchondral bone and thus leading to the cartilage degeneration and accelerated DDH progression.ConclusionsOur findings indicate that alternations of subchondral trabecular bone in a time-dependent manner could contribute to the DDH progression and the amelioration on subchondral bone might be a favorable therapeutic candidate for DDH.

Evaluation of antero-posterior instability of the hip using modified Lequesne's false profile view

BackgroundAccurate evaluation of hip instability is critical for the diagnosis and successful treatment of developmental dysplasia of the hip (DDH). However, dynamic evaluation of hip instability is not well established. This study aimed to use the lateral view from a radiograph to evaluate dynamic antero-posterior hip instability in patients with DDH. MethodsSeventy-four patients (92 hips) with DDH (DDH group) and 46 patients (59 hips) without hip pain and DDH (Control group) were examined. A false profile view (FPV) according to Lequesne was taken at standard and 90° flexion with the hip of interest defined as functional FPV; the translation of the center of the femoral head (CFH) obtained from the functional FPV was measured. As a validation test, we measured the anterior translation of the CFH using ultrasonography (US). ResultsThere was a significant difference between the two groups in the translation of the CFH (p < 0.01). The degree of CFH translation depended on the severity of DDH (lateral center edge angle, r = −0.56, p < 0.01; vertical center anterior margin angle, r = −0.57, p<0.01) and lateralization of the femoral head (head lateralization index, r = 0.54, p < 0.01). There was a significant correlation between functional FPV and US measurements (r = 0.71, p < 0.01). ConclusionThe present study confirmed that antero-posterior hip instability in DDH patients can be detected using functional FPV. Our novel measurement, as a new method for assessing hip instability, may be useful for evaluating hip dynamic instability in diagnosing the etiology, and determining and evaluating the treatment for DDH at lower cost and improved accessibility.

Three-Dimensional Evaluation of Innominate Bone Rotation in Female Patients with Developmental Dysplasia of the Hip.

BackgroundPatients with developmental dysplasia of the hip (DDH) are known to have abnormal pelvic morphologies; however, rotation of innominate bone features remains unclear. Thus, we investigated innominate bone rotation in patients with DDH by measuring the associated angles and distances using three-dimensional (3D) computed tomography.MethodsWe defined four straight lines in pelvic 3D models: from the anterior superior iliac spine to the posterior superior iliac spine, from the anterior inferior iliac spine to the posterior inferior iliac spine, from the pubic tubercle to the ischial spine, and from the pubic tubercle to the ischial tuberosity. Similarly, we measured the angles formed by these lines using the vertical axis of the anterior pelvic plane on the horizontal plane and the horizontal axis on the sagittal plane. Additionally, we measured the distances between the femoral head centers and the acetabular centers in the coronal plane.ResultsThe difference in internal rotation angle between the superior and inferior parts of the iliac bone was significantly lower, by approximately 1.7°, in the DDH group than in the control group (p = 0.007); the difference between the inferior and superior parts of the ischiopubic bone was significantly higher, by approximately 1.5°, in the DDH group (p < 0.001). In the sagittal plane, the sum of the superior aspect of the iliac bone and the inferior aspect of the ischium was significantly lower in the DDH group (p = 0.001) than in the control group. The distances between the femoral heads and the acetabula were significantly greater in the DDH group than in the control group (p = 0.03, p < 0.01, respectively).ConclusionsPatients with DDH had a more internally rotated ilium and ischiopubic bone than normal individuals; however, it should be emphasized that internal rotation was reduced near the acetabulum, and the acetabulum was shifted laterally. Similarly, it was shown that patients with DDH had different rotations of the ilium and ischiopubic bone in the sagittal plane.

Semi-automated measurement and analysis of three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip

To evaluate the three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip (DDH) using a semi-automated measurement software, which provides data for the differential diagnosis, surgical planning, surgical instrument design, and postoperative evaluation of hip related diseases. Eighty-four cases of CT data in asymptomatic population (asymptomatic group) and 47 cases of CT data in DDH patients (DDH group) were collected. There was no significant difference in gender and age (including age of male and female subgroups) between the two groups ( P<0.05). MaxTHA, a semi-automatic measurement software, was used to measure acetabular inclination and anteversion, including operative inclination (OI), radiographic inclination (RI), anatomic inclination (AI), operative anteversion (OA), radiographic anteversion (RA), and anatomic anteversion (AA). Comparisons were made between the two populations, between different Crowe classification subgroups, between different gender subgroups, and between left and right sides of acetabula. The comparison between asymptomatic group, healthy side of DDH group, and affected side of DDH group showed that there was no significant difference in acetabular orientation between asymptomatic group and healthy side of DDH group ( P>0.05). The OI, RI, and AI of affected side of DDH group were significantly higher than those in healthy side of DDH group and asymptomatic group, and AA was significantly lower than that in healthy side of DDH group and asymptomatic group ( P<0.05). The comparison between the normal acetabula and DDH acetabula with different Crowe classifications showed that there was no significant difference in the acetabulum orientation between Crowe Ⅰ group and the normal group ( P>0.05). The OI, RI, and AI of Crowe Ⅱ, Ⅲ, and Ⅳ groups were significantly higher than those of normal group ( P<0.05), the OI of Crowe Ⅲ group, RI and AI of Crowe Ⅳ group were significantly higher than those of Crowe Ⅰ group ( P<0.05), the AI of Crowe Ⅳ group was significantly higher than that of Crowe Ⅱ group ( P<0.05), and the OA, RA, and AA of Crowe Ⅲ group were significantly lower than other subgroups ( P<0.05) except Crowe Ⅰ group. The OA, RA, and AA in asymptomatic female group, and the OA and AI in DDH female group were significantly higher than those in all male groups ( P<0.05). The OI, RI, AI, and OA of the right acetabula in asymptomatic male group, and the RI and AI of the right acetabula in asymptomatic female group were significantly higher than those on the left side ( P<0.05). There were significant differences in acetabular orientation between asymptomatic and DDH populations, inter-group differences among Crowe classification subgroups, inter-gender differences among subgroups, and bilateral differences among asymptomatic individuals.

Novel Minimally-Invasive Triple Pelvic Osteotomy: JiShuiTan Minimally-Invasive Approach.

Triple pelvic osteotomy (TPO) is often performed to improve femoral head coverage, correct deformity, and stabilize the hip joint in a variety of pediatric orthopaedic conditions. After the TPO was first reported, many modifications were developed to simplify or improve the procedure, however, because of the specific anatomy with several critical nerves and vessels passing through the approaches, extensive exposure and prolonged intraoperative fluoroscopy are often required for TPO. This report introduces a novel, minimally-invasive surgical approach that minimizes the time of intraoperative fluoroscopy and size of the surgical incision, and reviews our experience. A total of 48 hips in 43 patients with a mean age of 8.3±1.7 years (range: 6.0 to 12.2 y) were included in this study. Of these, 21 patients (22 hips) had Legg-Calvé-Perthes disease (LCPD) and 22 patients (26 hips) had developmental dysplasia of the hip (DDH). The TPOs were performed using the novel, minimally-invasive TPO approach, with a mean postoperative follow-up of 38 months (range: 24 to 54 mo) in the DDH group and 44 months (range: 23 to 58 mo) in the LCPD group. The acetabular index (AI), femoral head migration rate (MP), center edge angle (CEA) and the Severin and Stulberg classification systems were used to evaluate the preoperative and postoperative results. SPSS software was used to analyze the data. The AI decreased from 33.8 degrees±9.2 to 2.9 degrees±10.1, the lateral CEA increased from -10.8 degrees±23.8 to 34.1 degrees±9.9, and the femoral head MP decreased from 64.0%±19.8% to 1.1%±2.6% in the DDH group at last follow-up, indicating significant improvement. The AI decreased from 20.8 degrees±4.7 to -1.3 degrees±7.3, the lateral CEA increased from 6.8 degrees±11.5 to 42.3 degrees±6.4, and the femoral head MP decreased from 42.2%±13.0% to 1.3%±3.3% in the LCPD group at last follow-up, also indicating significant improvement. This approach can simplify the TPO, making the complex operation safer, more effective, and capable of achieving satisfactory correction.

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

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). 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. 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. 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.