Unilateral Developmental Dysplasia Of The Hip Research Articles

2D/4D Finger Length Ratio in the Screening of Developmental Dysplasia of the Hip.

To investigate whether there is a relationship between the 2nd finger and 4th finger length measurement ratios and developmental dysplasia of the Hip (DDH). Cross-sectional observational study. Place and Duration of the Study:Department of Orthopaedics and Traumatology, Meram Faculty of Medicine Hospital, Konya, Turkiye, from January 2020 to May 2023. Infants were screened for DDH with Graff method for the ultrasounds of both hips. Lengths of the 2nd and 4th fingers of both hands were measured and recorded. Patients with additional risk factors for developmental dysplasia of the hip (breech birth, family history, oligohydramnios, swaddling) were excluded. Two hundred and fifty-six babies were screened including 55.1% (n = 141) girls and 44.9% (n = 115) boys. Their mean age was 2.51 ± 0.80 months. The average lengths were 31.73 ± 3.05 mm, for the left 2nd finger and 34.26 ± 3.48 mm for the left 4th finger. In the hip USG measurements, the mean alpha angles were 62.91 ± 3.12° for the right hip and, 63.20 ± 3.55° for the left hip. Eighteen (7%) of babies who underwent hip ultrasound (USG) had unilateral or bilateral DDH. Among these cases, 2.7% (n = 7) had right, 2.3% (n = 6) had left, and 2% (n = 5) had bilateral DDH. There was no statistically significant correlation between the ratios of right 2/4 finger lengths and the right alpha angle (rs = 0.051; p = 0.421). There was a statistically positive and statistically significant correlation between the ratios of left 2/4 finger lengths and the left alpha angle (rs = 0.154; p = 0.013). Only the left-hand finger ratio among the parameters in the model had a statistically significant effect on DDH. Therefore, the left hand 2D/4D finger length may be of value in screening for DDH. Developmental dysplasia of the hip, Second to fourth finger digit ratio, Ring finger, Digit ratios.

Prediction of the Labrum Shape in Patients With Developmental Dysplasia of the Hip Based on Pelvic Radiography.

The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum. We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH. Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups. We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674. The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum. III.

Transgluteal Ultrasonography in Spica Cast in the Post-reduction Assessment of Hip Developmental Dysplasia

Concentric circle reduction is one of the outcomes after reduction of developmental dysplasia of the hip (DDH). Radiography and magnetic resonance imaging (MRI) are used to confirm the reduction results. In this study, we evaluated the reduction results of the coronal section of the hip using transgluteal ultrasonography. We enrolled 46 children admitted to our hospital for closed or open reduction plaster fixation of DDH between January 2021 and December 2022. Thirty-eight patients had unilateral DDH, and eight patients had bilateral DDH. Transgluteal ultrasonography, radiography and MRI were done on the patients during the 7 d after reduction, and the results were interpreted by different radiologists. The covering of the femoral head and the distance between the medial margin of the femoral head and the acetabulum (HSD) were measured after calculating the maximum coronal surface of the iliac bone. MRI is regarded as the gold standard for determining hip reduction or dislocation. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ultrasound and radiography were determined and compared. The sensitivity, specificity, PPV and NPV of transgluteal ultrasonography were 100% (confidence interval [CI]: 69.2%-100%), 97.7% (CI: 88%-99.9%), 90.9% (CI: 59%-98.6%) and 100%, respectively, higher than those of radiography, which were 50% (CI: 18.7%-81.3%), 86.4% (CI: 72.6%-94.8%), 45.5% (CI: 24%-68.7%) and 88.4% (CI: 80.2%-93.5%), respectively. Ultrasonography had a higher sensitivity (100% vs. 50%, p < 0.01) and positive predictive rate (90.9% vs. 45.5%, p < 0.01) than radiography. Ultrasonography revealed that a distance between the head and socket (HSD) >8 mm indicated a strong suspicion for a poor reduction. Transgluteal coronal ultrasound scan with semiquantitative assessment of acetabular femoral head coverage and measurement of HSD can effectively monitor the reduction relationship between the two in children after DDH reduction.

Acetabular index as an indicator of Pavlik harness success in grade I developmental dysplasia of the hip: A retrospective study.

Some articles have focused on the effectiveness of the Pavlik harness treatment for unstable and dislocated hips, yet data on monitoring its effectiveness with the acetabular index remains elusive. Therefore, this study aimed to assess Pavlik harness effectiveness in infants ≤6 months diagnosed with grade I developmental dysplasia of the hip using acetabular index improvement and identify the possible predictors of successful Pavlik harness treatment. A retrospective review of infants with grade I acetabular dysplasia treated with a Pavlik harness and monitored with anteroposterior pelvis X-rays at presentation and follow-up. Successful treatment was defined as achieving an acetabular index <30°. A total of 231 infants with acetabular dysplasia were treated with a Pavlik harness. A successful outcome was achieved in 135 infants (58.4%). Younger age, lower initial acetabular index, and patients with unilateral developmental dysplasia of the hip were significant predictors of a successful outcome. An age of 4.5 months or older was found to be the threshold for an unsuccessful result following Pavlik harness treatment, with a sensitivity of 65.2% and specificity of 57.3%. An initial acetabular index of 35.5° was found to be the threshold for an unsuccessful result, with a sensitivity of 83.7% and specificity of 61.5%. Pavlik Harness's success in correcting the acetabular index in acetabular dysplasia patients was related to unilateral cases, a younger age at presentation, and a lower initial acetabular index. The thresholds for unsuccessful treatment were an age of 4.5 months or greater and an acetabular index of 35.5° or higher.

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.

Mechanical upside of PAO mainstream fixations: co-simulation based on early postoperative gait characteristics of DDH patients.

Purpose: To investigate the early postoperative gait characteristics of patients who underwent periacetabular osteotomy (PAO) and predict the biomechanical performance of two commonly used PAO fixation methods: iliac screw (IS) and transverse screw (TS). Methods: A total of 12 patients with unilateral developmental dysplasia of the hip (DDH) (mean age 27.81 ± 4.64years, 42% male) that were scheduled to undergo PAO surgery were included in this study. Their preoperative CT images and pre- and postoperative gait data were used to create subject-specific musculoskeletal models and complete the inverse dynamics analysis (IDA). Two patients with typical gait characteristics were selected using clustering analysis, and their IDA data were incorporated into finite element (FE) models of IS and TS fixations. Failure simulation was performed by applying iterative steps with increasing gait load to predict yield load. Stress results and yield loads were calculated for each FE model at different phases of the gait cycle. Results: Postoperative gait showed improvement compared to preoperative gait but remained inferior to that of healthy individuals. Postoperative gait was characterized by a lower hip range of motion, lower peri-ilium muscle forces, particularly in the abductors, and a sharper initial peak and flatter second peak of hip joint reaction force (HRF). Finite element analysis (FEA) showed a trend of increasing stress during the second-fourth phases of the gait cycle, with lower stress levels in other phases. At high-stress gait phases, the mean stress of maximum differed significantly between IS and TS (p < 0.05) and between coupled and uncoupled muscle forces (p < 0.05). Failure analysis predicted a slightly larger yield load for TS configurations (6.21*BW) than that for IS (6.16*BW), but both were well above the gait load. Coupled and uncoupled groups showed similar results, but uncoupled groups had lower yield loads (5.9*BW). Conclusion: PAO early postoperative gait shows a normalized trend, but abnormalities persist. IS and TS are both capable of resisting mechanical strain failure, with no significant mechanical advantage found for transverse screw fixation during PAO early postoperative gait. Additionally, it is important to note that the TS may have a higher risk of cyclic fatigue failure due to the localized greater stress concentration. Furthermore, the most medial screw is crucial for pelvic stability.

Assessing Leg Length Discrepancy Is Necessary Before Arthroplasty in Patients With Unilateral Crowe Type IV Hip Dislocation.

THA for high-riding developmental dysplasia of the hip (DDH) is challenging in terms of length equalization. Although previous studies suggested preoperative templating on AP pelvic radiographs is insufficient in patients with unilateral high-riding DDH because of hypoplasia of the hemipelvis on the affected side and unequal femoral and tibial length on scanograms, the results were controversial. The EOS™ (EOS™ Imaging) is a biplane X-ray imaging system using slot-scanning technology. Length and alignment measurements have been shown to be accurate. We used the EOS to compare the lower limb length and alignment in patients with unilateral high-riding DDH. (1) Is there an overall leg length difference in patients with unilateral Crowe Type IV hip dysplasia? (2) In patients with unilateral Crowe Type IV hip dysplasia with an overall leg length difference, is there a consistent pattern of abnormalities in the femur or tibia that account for observed differences? (3) What is the impact of unilateral high-riding Crowe Type IV dysplasia on femoral neck offset and knee coronal alignment? Between March 2018 and April 2021, we treated 61 patients with THA for Crowe Type IV DDH (high-riding dislocation). EOS imaging was performed preoperatively in all patients. Eighteen percent (11 of 61) of the patients were excluded because of involvement of the opposite hip, 3% (two of 61) were excluded for neuromuscular involvement, and 13% (eight of 61) had previous surgery or fracture, leaving 40 patients for analysis in this prospective, cross-sectional study. Each patient's demographic, clinical, and radiographic information was collected with a checklist using charts, Picture Archiving and Communication System, and an EOS database. EOS-related measurements that were related to the proximal femur, limb length, and knee-related angles were recorded for both sides by two examiners. The findings of the two sides were statistically compared. The overall limb length was not different between the dislocated and nondislocated sides (mean 725 ± 40 mm versus 722 ± 45 mm, mean difference 3 mm [95% CI -3 to 9 mm); p = 0.08). Apparent leg length was shorter on the dislocated side (mean 742 ± 44 mm versus 767 ± 52 mm, mean difference -25 mm [95% CI -32 to 3 mm]; p < 0.001). We observed that a longer tibia on the dislocated side was the only consistent pattern (mean 338 ± 19 mm versus 335 ± 20 mm, mean difference 4 [95% CI 2 to 6 mm]; p = 0.002), but there was no difference between the femur length (mean 346 ± 21 mm versus 343 ± 19 mm, mean difference 3 mm [95% CI -1 to 7]; p = 0.10). The femur of the dislocated side was longer by greater than 5 mm in 40% (16 of 40) of patients and shorter in 20% (eight of 40). The mean femoral neck offset of the involved side was shorter than that of the normal side (mean 28 ± 8 mm versus 39 ± 8 mm, mean difference -11 mm [95% CI -14 to -8 mm]; p < 0.001). There was a higher valgus alignment of the knee on the dislocated side with a decreased lateral distal femoral angle (mean 84° ± 3° versus 89° ± 3°, mean difference - 5° [95% CI -6° to -4°]; p < 0.001) and increased medial proximal tibia angle (mean 89° ± 3° versus 87° ± 3°, mean difference 1° [95% CI 0° to 2°]; p = 0.04). A consistent pattern of anatomic alteration on the contralateral side does not exist in Crowe Type IV hips except for the length of the tibia. All parameters of the limb length could be shorter, equal to, or longer on the dislocated side. Given this unpredictability, AP pelvis radiographs are not sufficient for preoperative planning, and individualized preoperative planning using full-length images of the lower limbs should be performed before arthroplasty in Crowe Type IV hips. Level I, prognostic study.

MRI hip morphology is abnormal in unilateral DDH and increased lateral limbus thickness is associated with residual DDH at minimum 10-year follow-up.

The purpose of the study was to compare the post-reduction magnetic resonance imaging morphology for hips that developed residual acetabular dysplasia, hips without residual dysplasia, and uninvolved contralateral hips in patients with unilateral developmental dysplasia of the hip undergoing closed or open reduction and had a minimum 10-year follow-up. Retrospective study of patients with unilateral dysplasia of the hip who underwent open/closed hip reduction followed by post-reduction magnetic resonance imaging. Twenty-eight patients with a mean follow-up of 13 ± 3 years were included. In the treated hips, residual dysplasia was defined as subsequent surgery for residual acetabular dysplasia or for Severin grade > 2 at latest follow-up. On post-reduction, magnetic resonance imaging measurements were performed by two readers and compared between the hips with/without residual dysplasia and the contralateral uninvolved side. Magnetic resonance imaging measurements included acetabular version, coronal/ axial femoroacetabular distance, acetabular depth-width ratio, osseous/cartilaginous acetabular indices, and medial/lateral (limbus) cartilage thickness. Fifteen (54%) and 13 (46%) hips were allocated to the "no residual dysplasia" group and to the "residual dysplasia" group, respectively. All eight magnetic resonance imaging parameters differed between hips with residual dysplasia and contralateral uninvolved hips (all p < 0.05). Six of eight parameters differed (all p < 0.05) between hips with and without residual dysplasia. Among these, increased limbus thickness had the largest effect (odds ratio = 12.5; p < 0.001) for increased likelihood of residual dysplasia. We identified acetabular morphology and reduction quality parameters that can be reliably measured on the post-reduction magnetic resonance imaging to facilitate the differentiation between hips that develop with/without residual acetabular dysplasia at 10 years postoperatively. level III, prognostic case-control study.

The Importance of Monitoring and Factors That May Influence Leg Length Difference in Developmental Dysplasia of the Hip.

This study assessed long-leg radiographs at skeletal maturity. Radiographs were assessed for the articulo-trochanteric distance (ATD) and femoral and tibial length. AVN was classified according to Kalamchi-MacEwen. 109 patients were included. The affected/DDH leg was longer in 72/109 (66%) patients. The length difference was mainly in the subtrochanteric segment of the femur. AVN negatively influenced leg length. Older (≥three years) patients with multiple procedures were more likely to have AVN. LLD interventions were performed in 30 (27.5%) patients. AVN grade or type of DDH surgery did not influence the odds of needing a procedure to correct LLD. Procedures to correct LLD were performed irrespective of previous DDH surgery or AVN grades. In most patients, the affected/DDH leg was longer, mainly in the subtrochanteric segment of the femur, largely influenced by femoral osteotomy in patients with multiple operative procedures for DDH. We recommend careful monitoring of LLD in DDH.

Coxa Magna following treatment of developmental dysplasia of the hip: investigation for associated potential factors.

Coxa Magna (CM) is defined as a condition in which the horizontal (transverse) diameter of the femoral head is larger on the affected side than on the intact side. CM can occur as a manifestation of avascular necrosis (AVN) following treatment for the developmental dysplasia of the hip (DDH). Alternatively, it can also be secondary to other hip disorders, such as Perthes' disease. This study aimed to determine the prevalence and indicators of CM and AVN of the femoral head that can be detected during follow-up in patients with unilateral DDH treated with closed reduction (CR) or open reduction (OR) surgery. The files of 143 patients treated for unilateral DDH between January 1997 and December 2017 were reviewed retrospectively. A total of 104 patients, including Group 1 ( n = 49) patients who underwent CR under general anesthesia and Group 2 ( n = 55) patients who underwent OR were included in the study. CM; It was considered as the case where the femoral head was 15% or more larger than the intact side. A total of 104 patients were followed up for 77.27 ± 13.96 months, with a mean age of 15.43 ± 7.76 months. When Group 1 and Group 2 were compared, there was no statistical difference in terms of sex, side, adductor tenotomy, and AVN ( P > 0.05). CM developed in 22.4% ( n = 11) of the patients in Group 1 and in 49.1% ( n = 27) in Group 2, and the difference was statistically significant ( P = 0.008). When the effect of independent variables on the development of CM is evaluated with the multivariate logistic regression model, the risk of developing CM is 3474 times higher in those who underwent iliopsoas tenotomy compared with those who did not. The primary outcome of this study is that CM is more frequent in patients treated with OR for DDH. CM may be a nonpathological condition that occurs in connection with iliopsoas tenotomy or surgical treatment. Prospective studies with a larger number of cases, designed to minimize confounding factors, are required.

Biomechanical Characteristics of the Femoral Isthmus during Total Hip Arthroplasty in Patients with Adult Osteoporosis and Developmental Dysplasia of the Hip: A Finite Element Analysis

This study investigated the underlying mechanisms of high fracture incidence in the femoral isthmus from a biomechanical perspective. We retrospectively analyzed a total of 923 primary total hip arthroplasty (THA) patients and 355 osteoporosis (OP) patients admitted from January 2010 to January 2018. Through a series of screening conditions, 47 patients from each group were selected for inclusion in the study. The datasets on the unaffected side and affected side of the patients with unilateral developmental dysplasia of the hip (uDDH) were respectively classified as the normal group (Group I) and he tDDH group (Group II), and that of patients with osteoporosis were classified as the OP group (Group III). In this study, first, we collected computed tomography (CT) images and measured geometric parameters (inner and outer diameters) of the isthmus. Thereafter, to study biomechanical properties, we established six finite element models and calculated values of von Mises stress for each group with the methods of data conversion and grid processing. Compared with those of patients in the normal group, the values of the inner and outer diameters of femoral isthmus of patients in the DDH group were significantly lower (P < 0.001), while the inner diameters of patients in the OP group were significantly higher (P < 0.001) and the outer diameters of patients in the OP group showed no significant difference (P> 0.05). The cortical rates of patients in the normal group and the DDH group appeared insignificant (P > 0.05), and those of patients in normal group were significantly higher than those of patients in the OP group (P < 0.001). Moreover, patients in the DDH group showed a higher von Mises stress value than patients in the normal group (P < 0.001), but statistically speaking the values between patients in the OP and normal groups were insignificant (P > 0.05). The relatively shorter inner and outer diameters of the isthmus in DDH resulted in intensive von Mises stress under the torque of the hip location, and induced a high fracture incidence. However, in patients in the OP group, the geometric morphology exhibited no anatomical variation, and the fracture was not due to the intensity of von Mises stress.

Is Hip Medial Ultrasound More Accurate Than Radiography for Determining the Status of Hip Reduction in Children Treated With a Spica Cast? A Retrospective Diagnostic Accuracy Study.

Is Hip Medial Ultrasound More Accurate Than Radiography for Determining the Status of Hip Reduction in Children Treated With a Spica Cast? A Retrospective Diagnostic Accuracy Study.

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.

Learning Curve of Total Hip Arthroplasty in Direct Anterior Approach without Requiring Corrective Osteotomy for Hip Dysplasia.

ObjectiveTo explore the learning curve of total hip arthroplasty in direct anterior approach (DA‐THA) without requiring corrective osteotomy for patients with unilateral developmental dysplasia of the hip (DDH) through the evaluation of clinical and radiographic results.MethodFrom December 2015 to January 2021, we retrospectively evaluated a surgeon's first 100 patients with unilateral hip dysplasia (Crowe I‐III) who underwent DA‐THA. All procedures were performed by a fellowship‐trained joint surgeon. Cementless hemispheric porous‐coated acetabular cups and tapered cementless stems were used in all hips. The radiographic data, including leg length, the height of the center of rotation, femoral head offset, the cup anteversion and inclination angle, were measured. The cumulative sum analysis (CUSUM) and risk‐adjusted cumulative sum analysis (RA‐CUSUM) were used to determine the learning curve of DA‐THA for each patient's operation time. By analyzing the operation time, complication rate, postoperative length of hospitalization and creatine kinase (before surgery and the third day after surgery), estimated blood loss, Harris score, radiographic data were compared between the different stages of the learning curve.ResultsThe mean follow‐up time was 35.45 ± 16.82 months. The CUSUM method obtained the maximum turning point of the curve at 43 cases, which divided the learning curve into Learning Period and Mastery Period. The CUSUM learning curve was best modeled as a cubic curve with the equation: CUSUM (min) = 0.001x 3 − 0.495x2 + 33.60x − 10.00, which had a higher R 2 value of 0.967. The pre‐operative data, creatine kinase, estimated blood loss and postoperative Harris scores of the two stages were not statistically significant (P > 0.05). The mean operation time was 118 min in the Learning Period and 87 min in the Mastery Period. Statistically significant differences were detected in the operation time (P < 0.001), postoperative length of hospitalization(P = 0.024), and postoperative leg length discrepancy (P = 0.012) between the two stages. The overall complication rates were 27.9% in the Learning Period and 12.3% in the Mastery Period (p = 0.049). The overall outliers of radiographic data were 34 cases in the Learning Period and 31 cases in the Mastery Period (79.07% vs 54.39%, P = 0.010).ConclusionsThe DA‐THA is a valuable alternative to achieve satisfactory clinical results for mild‐to‐moderate DDH patients. Furthermore, accurate analysis of the learning curve of DA‐THA for hip dysplasia by the CUSUM method showed that the surgeons need to finish about 43 cases to master the technique.

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.

Is There a Difference in Femur Length Between Neglected Developmental Dysplasia of The Hip (DDH) And Contralateral Normal Hip-Femur Length?: A Radiographic Study

Background and Aim: There are several anatomical problems with the hip joint that are associated with developmental dysplasia (DDH), such as the femoral head being out of place in relation to the acetabulum. First-born status, female sex, a positive family history, breech presentation, and oligohydramnios are all risk factors for preterm labor and birth. DDH severity has been graded using a variety of classification systems, including the Crowe classification, the Hartofilakidis classification, and the Eftekhar and Kerboul classification. The purpose of this study was to determine whether there is a difference in femur length between patients with neglected developmental dysplasia of the hip (DDH) and the normal femur. Materials And Methods: This is a case series study of 14 patients with Unilateral DDH who did not have surgery. Between January 2017 and December 2020, data were retrieved and obtained from our hospital’s picture archiving and communication system (P.A.C.S). A Pelvis x-ray and a Full-Length Femur x-ray were taken for those patients. As a radiological landmark, a fulllength film from the tip of the greater trochanter to the intercondylar space was used in this study. The following were the inclusion criteria: 1. The patient must be an adult who is at least 18 years old. 2. The deformity should only occur on one side (Unilateral DDH). 3. They had never had surgery before. 4. Crowe types III and IV Results: The mean age of the patients was 34 (SD 12.4) years, with females outnumbering males (71.4 % vs 28.6 %). Additionally, the mean length of the affected femur was 41.6 (SD 3.88) and the mean length of the normal femur was 42.2. (SD 4.08). When we compared the baseline characteristics of patients by age group (35 years vs 35 years), we discovered that the BMI of the older age group (35 years) was statistically significantly higher than the younger age group (35 years) (P-value =0.028) Conclusion: As a result of our study, we found an approximately 1 to 2 cm difference in femur length between patients with unilateral DDH and normal hip, which was correlated with age and body mass index (BMI). Preoperative considerations for unilateral DDH include taking a long film of both femurs to determine their relative length differences. This will assist in determining the amount of subtrochanteric femoral osteotomy to perform.

The Course and Anatomical Characteristics of Sciatic and Femoral Nerves in Unilateral Crowe Type-IV Hip Dysplasia

BackgroundThis study aims to investigate the course and anatomical characteristics of sciatic and femoral nerves in unilateral Crowe type-IV developmental dysplasia of the hip (DDH) patients.MethodsWe conducted a retrospective own-control study of patients with unilateral Crowe type-IV DDH. Bilateral hip computed tomography (CT) of 21 female patients was reviewed in our institute from February 2018 to February 2020. The distances between nerves and bony landmarks were measured in different CT sections (anterior superior iliac spine, acetabular inner wall, teardrop, and ischial tuberosity) to analyze the anatomical position and course of sciatic and femoral nerves between bilateral hips.ResultsIn the section of the acetabular inner wall, the distance between the femoral nerve and the acetabular anterior wall in affected hip (13.20 ± 3.59 mm) was significantly smaller than that in the healthy hip (16.58 ± 5.12mm) (p < 0.001). In other sections, the distances between nerves and bony landmarks in affected hips were significantly larger than or equal to those in the healthy hips.ConclusionIn female patients with unilateral Crowe type-IV DDH, the femoral nerve in the affected hip runs closer to the anterior acetabular wall than that in the healthy hip.

Use of ultrasonography to evaluate early outcomes of reduction in developmental dysplasia of the hip.

To compare pubo-femoral distance (PFD) in normal hips and those treated for developmental dysplasia of the hip (DDH) and to investigate the value of ultrasonography from the medial hip in early follow-up of dislocated DDH after reduction. This study included 58 infants (49 females) with DDH who presented with 65 dislocated hips (51 unilateral and 7 bilateral). Dislocation was treated by closed reduction for 53 and open reduction for 12 hips. Ultrasonography on the medial side of the hip was performed within 1-2weeks and 4weeks after reduction. The distance from the pubic bone to the femoral head (PFD) was measured to assess the reduction and stability of the femoral head and compared to that on the contralateral side (control) in cases of unilateral DDH. The PFD value for the normal group (2.9 ± 0.4mm) was significantly less than that for the closed reduction group (4.9 ± 2.8mm, P<0.001) and that for the open reduction group (4.4 ± 1.6mm; P=0.02), but no difference in the PFD was observed between the closed reduction and the open reduction groups (P=0.73). Despite successful reduction, the PFD values in the successful reduction group remained higher than those of the normal hips. PFD measurement by ultrasonography of the medial hip can be used to evaluate the effectiveness of reduction procedures in DDH. The clinical implications of post-reduction ultrasound evaluation in the diagnosis and long-term follow-up of outcomes require further research.

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.