Persistent Acetabular Dysplasia Research Articles

Developmental Dysplasia of the Hip (DDH): Etiology, Diagnosis, and Management.

Developmental dysplasia of the hip (DDH) is a complex disorder that refers to different hip problems, ranging from neonatal instability to acetabular or femoral dysplasia, hip subluxation, and hip dislocation. It may result in structural modifications, which may lead to early coxarthrosis. Despite identifying the risk factors, the exact aetiology and pathophysiology are still unclear. Neonatal screening, along with physical examination and ultrasound, is critical for the early diagnosis of DDH to prevent the occurrence of early coxarthrosis. This review summarizes the currently practised strategies for the detection and treatment of DDH, focusing particularly on current practices for managing residual acetabular dysplasia (AD). AD may persist even after a successful hip reduction. Pelvic osteotomy is required in cases of persistent AD. It could also be undertaken simultaneously with an open hip reduction. Evaluation of the residual dysplasia (RD) of the hip and its management is still a highly active area of discussion. Recent research has opened the door to discussion on this issue and suggested treatment options for AD. But there is still room for more research to assist in managing AD.

Outcome of Surgical Treatment of Developmental Dysplasia of the Hip in Aden, Yemen

Background: Developmental dysplasia of hip is a common condition presenting to a pediatric orthopedic surgeon. Objective: To evaluate the outcome of surgical treatment of developmental dysplasia of the hip. Materials and Method: This retrospective study conducted at the Department of Orthopedic Surgery in Alnaqeeb private hospital in Aden. The study children were 52 who were operated in the period from January 2016 to December 2018. Patient charts were reviewed and the collected data were sex, age, side, avascular necrosis, stiffness, re-dislocations, persistent acetabular dysplasia, and infection. The operations were open reduction and Pemberton's osteotomy plus minus femoral osteotomy without rotation. Statistical analyses were performed using SPSS version 22. We expressed distribution of variables using means and standard deviation (SD). Fisher test was used and p-value ≤ 0.05 was considered as statistically significant. Results: The majority of study children were females (80.8%). The age of the children ranged between 18 – 72 months. The mean age of children at surgery was 37 ± 17.5 months. The mean age of females was 37.2 ± 18.9 months while the mean age of males was 37.5 ± 10.7 months. The most common side was in the left side (51.9%). The mean time of follow-up was 34.7 ± 6.4 (range 24-48) months. Avascular necrosis found in (5.8%) children and stiffness found in (3.8%) children. Re-dysplasia of the hip were found in (5.8%) children. Persistent acetabular dysplasia was found in (3.8%) children. Additionally, we found superficial infection in (5.8%) children. Conclusion: The open reduction approach produces a better clinical outcome. The outcome of treatment in our study was comparable to published studies. Keywords: Developmental Dysplasia, hip, surgical treatment, outcome.

Incidence and risk factors for persistent acetabular dysplasia in patients with developmental dislocation of the hip treated by Pavlik Harness.

Some patients with developmental dysplasia of the hip (DDH) before 6 months of age successfully treated by Pavlik Harness (PH) still had persistent acetabular dysplasia (PAD). This study aimed to investigate the incidence and risk factors for PAD in patients with DDH treated by PH. We retrospectively reviewed the data of 89 patients (109 hips; mean age, 3.2 ± 1.5 months) with DDH treated by PH. Prior to treatment, all patients underwent ultrasound examination and classified according to Graf's method. PH was terminated once the hip achieved imaging recovery criteria. At final follow-up, the acetabular index (AI), center-edge angle (CEA) of Wiberg were measured on radiograph. Overall, 67/109 hips (61.5%) had successful PH treatment. Among these 67 hips, 58 hips (86.6%) achieved satisfactory outcome, nine (13.4%) had PAD. Age of the patients with PAD (4.3 ± 1 months) was significantly higher than those without PAD (2.8 ± 1.5 months) ( P = 0.001). Hips with PAD had higher mean Graf grade than those with satisfactory outcome ( P = 0.014). Logistic regression-confirmed age and Graf classification were risk factors for PAD. Overall, 55/67 (82.1%) met imaging recovery criteria to stop PH treatment, whereas 12/67 hips (17.9%) did not. The rate of PAD at final follow-up in patients achieving recovery criteria (4/55; 7.3%) was significantly lower than those not achieving it (41.7%) ( P = 0.007). In conclusion, age and Graf classification are risk factors for PAD. If hips are not normal at the end of PH treatment, the risk of PAD increases further.

Interobserver and Intraobserver Reliability in the Salter Classification of Avascular Necrosis of the Femoral Head in Developmental Dysplasia of the Hip.

Avascular necrosis (AVN) of the femoral head is a concerning complication that can result from treatments for developmental dysplasia of the hip (DDH). AVN can lead to degenerative osteoarthritis, persistent acetabular dysplasia, reduced function, and continuing hip pain. The incidence of AVN reported in the DDH literature is widely varied (0% to 73%). This variability may arise from lack of consensus on what constitutes true AVN in this patient population, and lack of clear criteria provided in studies reporting incidence rates. A multicentre, prospective database of infants diagnosed with DDH between 2010 and 2014 from 0 to 18 months of age was analyzed for patients treated by closed reduction (CR). Twelve pediatric orthopaedic surgeons completed 2 rounds of AVN assessments. Deidentified anteroposterior radiographs at most recent follow-up were provided to surgeons along with patient age at radiographic assessment, length of follow-up, ands affected hip. Ten of 12 surgeons completed a third round of assessments where they were provided with 1 to 2 additional radiographs within the follow-up period. Radiographic criteria for total AVN described by Salter and colleagues were used. Surgeons rated the presence of AVN as "yes" or "no" and kappa values were calculated within and between rounds. A total of 69 hips in 60 patients were assessed for AVN a median of 22 months (range: 12 to 36) post-CR. Interobserver kappa values for rounds 1, 2, and 3 were 0.52 (range: 0.11 to 0.90), 0.61 (range: 0.21 to 0.90), and 0.53 (range: 0.10 to 0.79), respectively. Intraobserver agreement for AVN diagnosis was an average of 0.72 (range: 0.31 to 0.96). Despite using the most commonly referenced diagnostic criteria, radiographic diagnosis of AVN following CR in DDH patients demonstrated only moderate agreement across surgeons. The addition of sequential radiographs did not improve cross-observer reliability, and while substantial agreement was seen within observers, the range of intraobserver kappa values was large. Level I-diagnostic study.

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.

Developmental dysplasia of the hip: update of management.

The term ‘developmental dysplasia of the hip’ (DDH) includes a wide spectrum of hip alterations: neonatal instability; acetabular dysplasia; hip subluxation; and true dislocation of the hip.DDH alters hip biomechanics, overloading the articular cartilage and leading to early osteoarthritis. DDH is the main cause of total hip replacement in young people (about 21% to 29%).Development of the acetabular cavity is determined by the presence of a concentrically reduced femoral head. Hip subluxation or dislocation in a child will cause an inadequate development of the acetabulum during the remaining growth.Clinical screening (instability manoeuvres) should be done universally as a part of the physical examination of the newborn. After two or three months of life, limited hip abduction is the most important clinical sign.Selective ultrasound screening should be performed in any child with abnormal physical examination or in those with high-risk factors (breech presentation and positive family history). Universal ultrasound screening has not demonstrated its utility in diminishing the incidence of late dysplasia.Almost 90% of patients with mild hip instability at birth are resolved spontaneously within the first eight weeks and 96% of pathologic changes observed in echography are resolved spontaneously within the first six weeks of life. However, an Ortolani-positive hip requires immediate treatment.When the hip is dislocated or subluxated, a concentric and stable reduction without forceful abduction needs to be obtained by closed or open means. Pavlik harness is usually the first line of treatment under the age of six months.Hip arthrogram is useful for guiding the decision of performing a closed or open reduction when needed.Acetabular dysplasia improves in the majority due to the stimulus provoked by hip reduction. The best parameter to predict persistent acetabular dysplasia at maturity is the evolution of the acetabular index.Pelvic or femoral osteotomies should be performed when residual acetabular dysplasia is present or in older children when a spontaneous correction after hip reduction is not expected.Avascular necrosis is the most serious complication and is related to: an excessive abduction of the hip; a force closed reduction when obstacles for reduction are present; a maintained dislocated hip within the harness or spica cast; and a surgical open reduction.Cite this article: EFORT Open Rev 2019;4:548-556. DOI: 10.1302/2058-5241.4.180019

Early Functional Outcomes of Periacetabular Osteotomy After Failed Hip Arthroscopic Surgery for Symptomatic Acetabular Dysplasia

Background: Persistent acetabular dysplasia is a common reason for the failure of hip arthroscopic surgery; however, the effect of prior hip arthroscopic surgery on functional outcomes after subsequent periacetabular osteotomy (PAO) is unknown. Hypothesis/Purpose: The purpose of this study was to (1) compare demographic and radiological findings in patients who had and had not undergone previous hip arthroscopic surgery before PAO for symptomatic acetabular dysplasia and (2) compare the short-term, hip-specific patient-reported outcomes in these same patient populations. It was hypothesized that prior hip arthroscopic surgery is associated with worse early functional outcomes in PAO. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective cohort study design was utilized. Patients undergoing PAO were enrolled from a single-center, prospective hip preservation registry from March 2011 to April 2015. Patients with a minimum of 1-year clinical follow-up with preoperative and postoperative outcome scores undergoing PAO were eligible for inclusion (n = 93 patients; mean clinical follow-up, 24 months [range, 11-58 months]). The study group consisted of patients undergoing PAO for symptomatic hip dysplasia after prior hip arthroscopic surgery (PREVSCOPE group; 22 patients, 25 hips). Patients undergoing PAO without prior hip arthroscopic surgery (PAOALONE group; 71 patients, 85 hips) were included as a comparison group. Demographic and radiological variables were recorded. Postoperative functional outcome scores (modified Harris Hip Score [mHHS], Hip Outcome Score [HOS], and International Hip Outcome Tool [iHOT-33]) were recorded at 6 months and annually postoperatively. Results: There were no demographic differences between the 2 groups at baseline. Acetabular version, femoral version, Tönnis grade, preoperative lateral center edge angle, and intraoperative procedures were not different between the 2 groups. At 1-year follow-up from the last hip surgical procedure, the mean (±SD) mHHS (73 ± 14 vs 86 ± 14, respectively; P < .001), HOS–Activities of Daily Living (84 ± 12 vs 93 ± 11, respectively; P = .007), HOS-Sport (62 ± 25 vs 85 ± 18, respectively; P < .001), and iHOT-33 (62 ± 21 vs 79 ± 20, respectively; P = .004) were decreased in the PREVSCOPE group versus the PAOALONE group. At last follow-up (mean, 18 months from the last hip surgical procedure), the mHHS and HOS-Sport were lower in the PREVSCOPE group versus the PAOALONE group. There was no difference in complication or reoperation rates between the 2 groups. Conclusion: Failed hip arthroscopic surgery before PAO for symptomatic hip dysplasia is associated with lower hip-specific functional outcomes within the first 1 year of follow-up despite similar baseline demographic and radiological characteristics. These differences persisted in certain outcome scores (mHHS, HOS-Sport) at last follow-up but were less pronounced than at 1 year.

Comparison of two different medial reference points for measurements of the acetabular index

Introduction: Acetabular index (AI) is a commonly used quantitative measurement of acetabular inclination in plain radiographs. Repeated measurements of this index are used to determine dysplasia in children and for decision making about surgical management. Persistent acetabular dysplasia may be an indication for performing an acetabuloplasty. AI is commonly measured between the Hilgenreiner’s line (line that connects both triradiate cartilages) and the line joining lateral most ossified margin of the acetabulum and triradiate cartilage. Two different methods for measurement of AI with two different medial reference points at the triradiate cartilage have appeared in the literature. Aim: The specific aim of the study was to investigate the difference between AI measurements with two different methods and report on intraobserver and interobserver reliability of both the methods. Materials and Methods: Ninety-eight children with developmental dysplasia of the hip (DDH) (treated and untreated), younger than 9 years, were included in the study. Anteroposterior radiographs of the pelvis having acceptable pelvic rotation and pelvic tilt were included in the study. AI was measured using two different reference points for the affected and normal sides. AI was measured twice at 1-month interval by two investigators. The difference between the two measurement techniques was compared by the paired “t” test. Pearson’s correlation coefficient was calculated to test associations between the two measurement techniques. Results: The reproducibility of measurements of both the techniques was found satisfactory [intraclass correlation (ICC)-0.90 and 0.87]. Statistically significant difference (P value < 0.001) (5.7° for affected and 5.3° for normal side) between the indices measured by two techniques was noted. This difference was noted for all age groups. Significant positive correlations between both the techniques were noted in normal as well as dysplastic hips. Conclusion: Acetabular indices measured with two different medial points gave significantly different values. All subsequent assessment should be consistently carried out by the same method.

Pelvic osteotomies for the treatment of hip dysplasia in children and young adults.

Persistent acetabular dysplasia is a well-known cause of premature hip osteoarthritis. In the dysplastic hip, point loading occurs at the edge of the steep, shallow acetabulum. Pelvic osteotomies reduce this load by increasing the contact area, relaxing the capsule and muscles about the hip, improving the moment arm of the hip, and normalizing the forces of weight bearing. The orthopaedic surgeon can choose from among a variety of pelvic osteotomies (e.g., redirectional, reshaping, and salvage) for the purpose of restoring normal anatomy and biomechanical forces across the hip joint. Treatment of residual dysplasia is based on the patient's age and the presence or absence of congruent hip reduction. A Salter or Pemberton procedure is generally appropriate for a child between the ages of 2 and 10. A triple innominate osteotomy can be considered for the older child or adolescent in whom the triradiate cartilage remains open. After triradiate closure, the Ganz periacetabular osteotomy can be considered in addition to the triple innominate osteotomy.

Treatment of Hip Dysplasia in Older Children With a Combined One-Stage Procedure

This retrospective study was conducted to determine the efficacy and complication rates associated with treating children of ambulatory age with idiopathic developmental dysplasia of the hip with open reduction and combined femoral and pelvic osteotomies. Eighteen hips were reviewed in 13 patients. The average patient age at surgery was 29 months (range, 15-117 months), with an average followup of 43 months (range, 24-78 months). Preoperative Tonnis classification identified six Class II, seven Class III, and five Class IV hips. Followup Severin classification identified 16 Class 1A and two Class 2A hips. The average center edge angle on most recent followup was 47 degrees (range, 25 degrees-70 degrees), and the acetabular index was 5 degrees (range, 0 degree-20 degrees). Avascular necrosis developed in one (5.5%) patient. Clinically, all patients were pain free with ambulation and had excellent results by McKay criteria. No patient required a second surgical procedure for recurrent subluxation or persistent acetabular dysplasia. The treatment of children who are of ambulatory age with developmental dysplasia of the hip using open reduction and combined osteotomies was safe and effective.

Open reduction technique

Closed reduction of a hip dislocation will prove even more difficult if the dislocation has existed over a longer period of time. The indication is based on several principles: An open reduction may be carried out only after an unsuccessful attempt to perform a closed reduction or at a fixed age limit (12 or 24 months) or based upon arthrographic findings. In our department, for babies up to the age of 12 months, we always try to perform a closed reduction. Between 12 to 24 months, arthrographic findings will determine the choice of method. After the age of two, as a rule, we use an open reduction. The preliminary treatment consists of longitudinal traction. Current methods of approach to the hip joint are the medial approach according to Ludloff or the frontal approach by means of an inguinal incision. With the medial approach, there is greater risk of damaging the circumflex artery; also, a higher rate of avascular necrosis of the femoral head has been observed. Therefore, we only practice the ventral approach. Mainly for cosmetic reasons, however, instead of using the Smith-Petersen procedure, we apply a pure inguinal incision proximal to the inguinal ligament. The approach is found by detaching the muscle tissue at the anterior and interior iliac spine. Medially and laterally of the pelvic ridge, though, the tissue may be left. The joint capsule may be opened in the shape of a T or a V. A t-shape incision offers a better survey, whereby the risk of damaging a vessel is somewhat higher. In addition to resection of the teres ligament, it is necessary to indent the transverse acetabular ligament. Often, aponeurotic recession of the psoas tendon must be performed as well and the labrum indented and pushed outwards before reduction. The risk of insufficient development of the acetabulum can be minimized only if the femoral head is optimally centered. If the femoral head is in a high position (i.e., if the upper ridge of the femoral metaphysis lies higher than the triradiate cartilage), a shortening osteotomy of the femur should always be performed. This is the only possibility of repositioning the femoral head without exercising exaggerated pressure. On the other hand, we are rather reticent to perform a pelvic osteotomy at the time of repositioning. For children under 2 years of age, we recommend to that the acetabulum be allowed to develop and that a pelvic osteotomy be performed at a lager period if necessary. Postoperative treatment is given for a period of 12 weeks in a hip-leg cast in the Fettweis position, followed by another 3 months in a splint. Possible complications are redislocations, avascular necrosis of the femoral head and persistent acetabular dysplasia. An optimal technique will considerably reduce the risks of such complications.

Congenital dislocation of the hip in boys.

Fifty-five boys with seventy-eight congenitally dislocated hips were treated between 1965 and 1990. The patients were divided into three groups according to the initial treatment. Group I included thirty hips (twenty-two boys) that had been treated initially with a Pavlik harness. Two hips (7 per cent) had a successful outcome, and twenty-eight (93 per cent) needed additional methods of treatment. Group II included forty-two hips (twenty-nine boys) that had been treated initially with closed reduction and immobilization in a hip-spica cast. After the closed reduction, twenty-nine hips (69 per cent) were considered stable, although fifteen (52 per cent) of them needed a secondary procedure because of residual subluxation or persistent acetabular dysplasia. Thirteen hips (31 per cent) were considered unstable after the closed reduction and subsequently had an open reduction. Group III included six hips (four boys) that had been treated initially with open reduction. Two of these hips redislocated after the open reduction, and they were reduced with an additional open reduction. A pelvic osteotomy was later performed to treat persistent acetabular dysplasia in these two hips. Two hips that had been treated with an open reduction and concomitant pelvic and femoral procedures did not need additional treatment. This study demonstrates that boys who have congenital dislocation of the hip do not always respond well to treatment and constitute a high-risk group.

The acetabular response to proximal femoral varus rotational osteotomy. Results after failure of post-reduction abduction splinting in patients who had congenital dislocation of the hip.

The acetabular response to proximal femoral varus rotational osteotomy was studied radiographically in twenty-eight patients who had had thirty-three congenitally dislocated hips. All of the patients had previously been managed with open or closed reduction followed by use of a spica cast and had worn an abduction orthosis for at least one year after the reduction. The indications for the femoral osteotomy were a persistently increased acetabular index or subluxation, or both. The average of the patients at the time of the femoral osteotomy was twenty-five months. The average preoperative acetabular index was 32 degrees. At an average of seven years after the osteotomy, the acetabular index had improved to an average of 16 degrees. Four hips had had one subsequent procedure for persistent acetabular dysplasia. Despite a failure of the acetabulum to respond to use of an abduction splint, the proximal femoral varus rotational osteotomy stimulated improvement in the acetabular index to within normal limits in twenty-nine of the thirty-three hips.

Computed tomography for early evaluation of developmental dysplasia of the hip.

Computed tomography (CT) provides an axial image of the dysplastic hip. We reviewed 130 CT scans performed after closed reduction for developmental dysplasia of the hip (DDH) in 42 patients (52 hips). We evaluated methods of measuring CT scans and found no described measurement that was predictive of development of avascular necrosis (AVN) or persistent acetabular dysplasia. The CT scan provides an excellent image of the infant hip when the child is in a spica cast and is useful to confirm an adequate reduction. No patient in this series lost reduction after 2 weeks.