[Femoroacetabular impingement in 2024 : concept and diagnosis]. / Conflit fémoro-acétabulaire : concept et diagnostic.

Femoroacetabular impingement (FAI) is a condition that predominantly affects young people between the ages of 20 and 40. It is characterized by hip pain associated with reduced range of movement of the hip joint. If left untreated, FAI leads to osteoarthritis. When first described in the scientific literature in 2003, the concept of FAI was based on two different anatomic features: cam-type deformity and pincer-type deformity. Since that initial description clinical experience and scientific investigation have identified a third pillar of FAI: abnormal femoral torsion. This first article reviews the concept and diagnosis of FAI.

Le conflit fémoro-acétabulaire (CFA) est une pathologie qui touche les sujets jeunes de 20 à 40 ans, entraînant des douleurs associées à une diminution de l'amplitude de mouvement de l'articulation de la hanche. Non traité, le CFA est responsable d'une coxarthrose précoce. Lors de sa première description dans la littérature scientifique en 2003, le concept du CFA était basé sur deux piliers : came et pince. Ces 20 dernières années, de nouvelles connaissances ont émergé, avec notamment la mise en évidence du rôle important de la torsion fémorale, considérée à présent comme le troisième pilier du CFA. Ce premier article fait le point sur le concept et le diagnostic du CFA.

[Systematic evaluation of the painful hip]. / Evaluación sistemática de la cadera dolorosa.

The painful hip has been a topic of study that has evolved from the beginning of the last century to the present. The clinical approach is complex, and requires a systematization process associated with good questioning, clinical maneuvers with their corresponding interpretation, and complementary imaging studies. The understanding of hip pathology, especially in young adults, is highly simplified and sometimes underdiagnosed, therefore, not treated in a timely manner. The prevalence of painful hip is more common in males (49 to 55%) than in females (25 to 28%), and the causes may vary according to demographic characteristics and the history of each patient. Bryan Kelly, made a topographic and anatomical description of the approach to the painful hip according to the theory or system of the layers: I. Osteochondral layer; II. Inert layer; III. Contractile layer; and IV. Neuro-mechanical layer. This system helps us understand the anatomical site of pain and its clinicopathological correlation. The semiological approach to hip pain is the fundamental pillar for differential diagnosis. We can divide it according to its topography into anterior, lateral and posterior, as well as according to its chronology and characteristics. The physical examination should be carried out systematically, starting from a generalized inspection of gait and posture to the evaluation of specific signs for alterations in each layer, which evoke pain with specific postures and ranges of mobility, or weakness and alterations in the arc of mobility of the joint. Image evaluation is initially recommended with radiographic projections that evaluate different planes, both coronal, sagittal and axial, complemented with panoramic views, and eventually dynamic sagittal ones if necessary. Requesting specific studies such as tomography to evaluate bone structure and reserve, or simple MRI when there is suspicion of soft tissue affection, or failing that, arthroresonance for joint pathology, will depend on the clinical symptoms and radiographic findings.

La cadera dolorosa ha sido un tema de estudio que ha evolucionado desde principios del siglo pasado hasta la actualidad. El abordaje clínico es complejo y exige un proceso de sistematización asociado a un buen interrogatorio, maniobras clínicas con su interpretación correspondiente y estudios de imagen complementarios. El entendimiento de la patología de cadera, sobre todo en adulto joven, es altamente simplificado y en ocasiones infradiagnosticado, por lo tanto, no tratado en tiempo y forma. La prevalencia de cadera dolorosa es más frecuente en el sexo masculino (49 a 55%) que en el femenino (25 a 28%), y las causas pueden variar de acuerdo a características demográficas y a los antecedentes de cada paciente. Bryan Kelly realizó una descripción topográfica y anatómica del abordaje de la cadera dolorosa de acuerdo con la teoría o sistema de las capas: I. Capa osteocondral; II. Capa inerte; III. Capa contráctil; y IV. Capa neuromecánica. Este sistema nos ayuda a entender el sitio anatómico del dolor y su correlación clínico-patológica. El abordaje semiológico del dolor de cadera es el pilar fundamental para el diagnóstico diferencial. Podemos dividirlo de acuerdo con su topografía en anterior, lateral y posterior, así como de acuerdo a su cronología y características. La exploración física debe realizarse de manera sistemática, iniciando desde inspección generalizada, de la marcha y postura hasta la evaluación de signos específicos para alteraciones en cada capa, los cuales evocan dolor con posturas y arcos de movilidad específicos, o bien debilidad y alteraciones en el arco de movilidad de la articulación. La evaluación por imagen se recomienda inicialmente con proyecciones radiográficas que evaluen diferentes planos, tanto coronal, sagital y axial, complementado con panorámicas, y eventualmente sagitales dinámicas de ser necesarios. Solicitar estudios específicos como tomografía para evaluar estructura y reserva ósea, o bien, resonancia simple cuando hay sospecha de afección a tejidos blandos, o en su defecto, artrorresonancia para patología articular, dependerá de la clínica y los hallazgos radiográficos.

Effect of the presence of cysts in the hip joint on hip arthroscopy.

OBJECTIVES: The aim of this study was to investigate whether the presence and size of fibrous cysts affected postoperative results in patients undergoing hip arthroscopy. PATIENTS AND METHODS: Between January 2010 and December 2019, a total of 261 patients (138 males, 123 females; mean age: 39.5±11.9 years; range, 18 to 66 years) who underwent hip arthroscopy with the diagnosis of cam-pincer-mixed-type femoroacetabular impingement (FAI) and labral pathologies were retrospectively analyzed. The study groups (impingements and labral pathologies) and the presence of cyst (or cyst size: <5 mm, 5-8 mm, >8 mm) were used as the fixed effects, and the analysis was adjusted for baseline age, sex, and preoperative scores. Pre- and postoperative modified Harris Hip Score (mHHS) and Visual Analog Scale (VAS) scores that were applied to all patients were used as an indication of clinical results. RESULTS: The mean preoperative mHHS score of the patients with a cyst was significantly lower compared to the patients without a cyst (56.8±12.3 vs. 60.3±12.7, p=0.026). The mean change in the mHHS score and the mean percentage change in VAS score were significantly higher in the patients with a cyst compared to the patients without a cyst (mHHS score: 28.1±14.0 vs. 22.5±14.1, p=0.002; VAS score: 61.9±30.2 vs. 52.6±47.4, p=0.038). The increase in mHHS score over time for patients with a cyst was significantly higher than the patients without cysts in the pincer group (38.1±11.1 vs. 19.3±13.5, p<0.001). The patients with a cyst size of >8 mm had a significantly higher increase in the mHHS scores compared to the patients with a cyst size of <5 mm (29.5±12.9 vs. 23.5±13.8, p=0.043). CONCLUSION: Subchondral cysts in the femoral head and neck junction accompanied cam-type and mixed-type FAI, while subchondral cysts in the acetabulum accompanied pincer-type impingement. In all groups, the mean increase in mHHS scores and the mean decrease in VAS scores were higher in patients with subchondral cysts than in patients without cysts. In patients with subchondral cysts, if the lesion causing FAI is treated arthroscopically, it can positively affect the functional results.

Factors influencing the survival status of the hip joint in post-collapse femoral head necrosis.

BACKGROUND: Despite hip function typically deteriorating in the post-collapse stage of osteonecrosis of the femoral head (ONFH), some patients can still demonstrate long-term favorable hip function, a state termed "survival with collapse". This study aims to identify the characteristics of patients suitable for "survival with collapse" in cases of ONFH. METHODS: This cross-sectional study included 65 patients (87 hips) diagnosed with post-collapse ONFH for ≥ 3 years (average 9.1 years, range 3-23 years). Hip function was assessed using the Harris Hip Score (HHS). Demographic, clinical, and radiographic data were compared between the favorable group (HHS > 80) and the poor group (HHS ≤ 80). Independent protective factors for hip function were identified by multivariate analysis and receiver operating characteristic (ROC) curve analysis was further applied to evaluate these factors' diagnostic efficacy. RESULTS: The favorable and poor groups included 46 and 41 hips, respectively. Significant differences were found in body mass index (BMI), Association Research Circulation Osseous (ARCO) stage, collapse degree, Japanese Investigation Committee (JIC) classification, necrotic size, and hip subluxation between the two groups (p < 0.05). Multivariate logistic regression identified collapse < 3 mm(OR:14.49, 95%CI: 3.52-59.68, p < 0.001), JIC types B (OR: 11.08, 95% CI: 1.07-115.12, p < 0.05) and C1(OR: 5.18, 95% CI: 1.47-18.20, p < 0.05) as independent protective factors for hip function, while BMI (OR: 0.76, 95% CI: 0.59-0.97, p = 0.029) was an independent risk factor. ROC curve analysis demonstrated that both collapse degree (AUC = 0.798, sensitivity = 91.3%, specificity = 68.3%, p < 0.0001) and JIC classification (AUC = 0.787, sensitivity = 80.4%, specificity = 73.2%, p < 0.0001) had satisfactory diagnostic value for hip function. Combining JIC classification and collapse degree (AUC = 0.868, sensitivity = 76.1%, specificity = 85.4%, p < 0.0001) significantly enhanced diagnostic efficacy compared to using either alone (p < 0.05). CONCLUSION: In ONFH, femoral head collapse does not necessarily determine a poor prognosis. Patients with mild collapse (< 3 mm) and preserved anterolateral wall are more likely to retain satisfactory hip function, making them candidates for "survival with collapse."

The relationship between MRI-detected hip abnormalities and hip pain in hip osteoarthritis: a systematic review.

Magnetic resonance imaging (MRI) is increasingly used in the classification and evaluation of osteoarthritis (OA). Many studies have focused on knee OA, investigating the association between MRI-detected knee structural abnormalities and knee pain. Hip OA differs from knee OA in many aspects, but little is known about the role of hip structural abnormalities in hip pain. This study aimed to systematically evaluate the association of hip abnormalities on MRI, such as cartilage defects, bone marrow lesions (BMLs), osteophytes, paralabral cysts, effusion-synovitis, and subchondral cysts, with hip pain. We searched electronic databases from inception to February 2024, to identify publications that reported data on the association between MRI features in the hip joint and hip pain. The quality of the included studies was scored using the Newcastle-Ottawa Scale (NOS). The levels of evidence were evaluated according to the Cochrane Back Review Group Method Guidelines and classified into five levels: strong, moderate, limited, conflicting, and no evidence. A total of nine studies were included, comprising five cohort studies, three cross-sectional studies, and one case-control study. Moderate level of evidence suggested a positive association of the presence and change of BMLs with the severity and progress of hip pain, and evidence for the associations between other MRI features and hip pain were limited or even conflicting. Only a few studies with small to modest sample sizes evaluated the association between hip structural changes on MRI and hip pain. BMLs may contribute to the severity and progression of hip pain. Further studies are warranted to uncover the role of hip MRI abnormalities in hip pain. The protocol for the systematic review was registered with PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ , CRD42023401233).

Advances in Molecular Research on Hip Joint Impingement-A Vascular Perspective.

With the rise in longevity within the population, medicine continues to encounter fresh hurdles necessitating prompt actions, among which are those associated with hip joint aging. Age-related arthropathies encompass damage to bones' articulating extremities and their supporting structures, such as articular cartilage, and alterations in the quantity and quality of synovial fluid. This study aims to summarize the biomolecular methods of hip joint evaluation focused on its vascularization, using data correlated with biomolecular research on other joints and tissues, in order to reach an objective opinion of the study prospects in this field. Following a retrospective study on most modern biomolecular research methods on the synovium, the capsule, and the articular cartilage of the hip joint, we have hereby concretized certain future research directions in this field that will improve the qualitative and morphofunctional management of the hip joint at an advanced age, even within population categories at risk of developing various degenerative joint pathologies.

Bilateral transient osteoporosis of the hip: a neglected cause of hip pain during pregnancy.

Transient osteoporosis of the hip (TOH) is an important but often neglected cause of hip pain, which can gradually lead to debilitating mobility and carries risks such as fracture or avascular necrosis. A 39-year-old woman presented to the Rheumatology department two weeks post-cesarean delivery, reporting the onset of left mechanical hip pain since the 33rd week of pregnancy. After delivery, similar complaints emerged on the right side. Hip X-ray showed a decrease in bone density in the left hip. Later, Magnetic Resonance Imaging revealed bilateral bone marrow edema in both proximal femurs. The diagnosis of TOH was established, and the patient was treated with conservative measures. Seven months later, she was asymptomatic. Pregnancy is a recognized risk factor for TOH, especially in the last trimester. It is an important differential diagnosis to consider in cases of hip pain in pregnant or newly breastfeeding women.

Deep Learning Reconstruction of Accelerated MRI: False-Positive Cartilage Delamination Inserted in MRI Arthrography Under Traction.

OBJECTIVES: The radiological imaging industry is developing and starting to offer a range of novel artificial intelligence software solutions for clinical radiology. Deep learning reconstruction of magnetic resonance imaging data seems to allow for the acceleration and undersampling of imaging data. Resulting reduced acquisition times would lead to greater machine utility and to greater cost-efficiency of machine operations. MATERIALS AND METHODS: Our case shows images from magnetic resonance arthrography under traction of the right hip joint from a 30-year-old, otherwise healthy, male patient. RESULTS: The undersampled image data when reconstructed by a deep learning tool can contain false-positive cartilage delamination and false-positive diffuse cartilage defects. CONCLUSIONS: In the future, precision of this novel technology will have to be put to thorough testing. Bias of systems, in particular created by the choice of training data, will have to be part of those assessments.

Case 326: Intra-Articular Osteoid Osteoma.

HISTORY: A 15-year-old male patient presented with a 3-week history of inner left thigh pain provoked by activity and experienced occasionally at rest. The patient denied nighttime pain, fever, or chills. Laboratory investigation revealed the following normal values: hemoglobin level of 15.6 g/dL (normal range, 13-16 g/dL), platelet count of 240 × 103/µL (normal range, 140-440 × 103/µL), and total leukocyte count of 7100 cells/µL (normal range, 4500-11 000 cells/µL). The percentage of neutrophils was considered low at 44% (normal range, 54%-62%), and the percentage of eosinophils was slightly high at 3.7% (normal range, 0%-3%). An anteroposterior radiograph of the left hip is shown. Physical therapy was initiated, with no improvement after 2 weeks of therapy. The patient was referred to an orthopedist for further evaluation. At physical examination, the patient endorsed marked left hip pain with hip flexion to 90°, limited internal and external rotation (5° and 15°, respectively), and antalgic gait favoring the left leg. Hip MRI and further serologic analysis were requested for further evaluation. Although the serologic testing was performed at an outside laboratory, the physician reported positive immunoglobulin-G Lyme titers, normal C-reactive protein level, and normal erythrocyte sedimentation rate. Pelvic CT was requested. The patient was prescribed a course of doxycycline (100 mg twice daily for 28 days), with reported resolution of symptoms 2 weeks after initiation of treatment. Three weeks later, the patient presented to our department with recurrent left hip pain, which was similar in severity compared with the initial presentation. A second MRI examination of the left hip was performed 4 months after the initial presentation.

Diagnostic and prognostic relevance of plain radiographs for periprosthetic joint infections of the hip: a literature review.

Conventional radiography is regularly used to evaluate complications after total hip arthroplasty. In various recent consensus meetings, however, plain radiographs of a potentially infected hip joint have been judged as being only relevant to exclude diagnoses other than infection. Solid data on radiographic presentations of periprosthetic joint infection (PJI) are scarce. As a result, the prognostic value of radiological features in low-grade PJI remains uncertain. The present review article aims to present an overview of the available literature and to develop ideas on future perspectives to define the diagnostic possibilities of radiography in PJIs of the hip. The primary outcome of interest of this systematic review was the radiologic presentation of periprosthetic joint infections of the hip. As secondary outcome of interest served the sensitivity and specificity of the radiologic presentation of periprosthetic joint infections. Of the included articles, 26 were reviews, essays, or case reports and only 18 were clinical studies. Typical radiologic abnormalities of PJI were a periosteal reaction, a wide band of radiolucency at the cement-bone or metal-bone interface, patchy osteolysis, implant loosening, bone resorption around the implant, and transcortical sinus tracts. The frequency of their occurrence is still inadequately defined. A deeper understanding of the underlying causes and the relation between microorganisms to radiologic abnormalities can probably help clinicians in the future to diagnose a PJI. This is why further research shall focus on the radiographic features of PJI.

Application of AI-assisted MRI for the identification of surgical target areas in pediatric hip and periarticular infections.

OBJECTIVE: To develop an AI-assisted MRI model to identify surgical target areas in pediatric hip and periarticular infections. METHODS: A retrospective study was conducted on the pediatric patients with hip and periarticular infections who underwent Magnetic Resonance Imaging(MRI)examinations from January 2010 to January 2023 in three hospitals in China. A total of 7970 axial Short Tau Inversion Recovery (STIR) images were selected, and the corresponding regions of osteomyelitis (label 1) and abscess (label 2) were labeled using the Labelme software. The images were randomly divided into training group, validation group, and test group at a ratio of 7:2:1. A Mask R-CNN model was constructed and optimized, and the performance of identifying label 1 and label 2 was evaluated using receiver operating characteristic (ROC) curves. Calculation of the average time it took for the model and specialists to process an image in the test group. Comparison of the accuracy of the model in the interpretation of MRI images with four orthopaedic surgeons, with statistical significance set at P < 0.05. RESULTS: A total of 275 patients were enrolled, comprising 197 males and 78 females, with an average age of 7.10 ± 3.59 years, ranging from 0.00 to 14.00 years. The area under curve (AUC), accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 1 were 0.810, 0.976, 0.995, 0.969, 0.922, and 0.957, respectively. The AUC, accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 2 were 0.890, 0.957, 0.969, 0.915, 0.976, and 0.972, respectively. The model demonstrated a significant speed advantage, taking only 0.2 s to process an image compared to average 10 s required by the specialists. The model identified osteomyelitis with an accuracy of 0.976 and abscess with an accuracy of 0.957, both statistically better than the four orthopaedic surgeons, P < 0.05. CONCLUSION: The Mask R-CNN model is reliable for identifying surgical target areas in pediatric hip and periarticular infections, offering a more convenient and rapid option. It can assist unexperienced physicians in pre-treatment assessments, reducing the risk of missed and misdiagnosis.

Joint-specific regulation of homeobox D10 expression in rheumatoid arthritis fibroblast-like synoviocytes.

Rheumatoid arthritis (RA) is a systemic immune-mediated disease characterized by joint inflammation and destruction. The disease typically affects small joints in the hands and feet, later progressing to involve larger joints such as the knees, shoulders, and hips. While the reasons for these joint-specific differences are unclear, distinct epigenetic patterns associated with joint location have been reported. In this study, we evaluated the unique epigenetic landscapes of fibroblast-like synoviocytes (FLS) from hip and knee synovium in RA patients, focusing on the expression and regulation of Homeobox (HOX) transcription factors. These highly conserved genes play a critical role in embryonic development and are known to maintain distinct expression patterns in various adult tissues. We found that several HOX genes, especially HOXD10, were differentially expressed in knee FLS compared with hip FLS. Epigenetic differences in chromatin accessibility and histone marks were observed in HOXD10 promoter between knee and hip FLS. Histone modification, particularly histone acetylation, was identified as an important regulator of HOXD10 expression. To understand the mechanism of differential HOXD10 expression, we inhibited histone deacetylases (HDACs) with small molecules and siRNA. We found that HDAC1 blockade or deficiency normalized the joint-specific HOXD10 expression patterns. These observations suggest that epigenetic differences, specifically histone acetylation related to increased HDAC1 expression, play a crucial role in joint-specific HOXD10 expression. Understanding these mechanisms could provide insights into the regional aspects of RA and potentially lead to therapeutic strategies targeting specific patterns of joint involvement during the course of disease.

Rapidly destructive hip osteoarthritis: a diagnosis not to miss.

This review illustrates the imaging features of rapidly destructive hip osteoarthritis (RDHO) across different imaging modalities. RDHO is a rare joint disease of unknown aetiology resulting in rapid deterioration of the hip joints. Patients often present with severe hip pain and can progress to complete joint destruction in 6 months to 3 years causing disability. Since its clinical and imaging features often overlap with other conditions, the diagnosis is easily missed in daily practice. The purpose of this paper is to outline the characteristic imaging features of RDHO, aiming to enhance awareness of this disease entity and promote timely treatment for patients. Sequential radiographs are particularly important in demonstrating the rapid progression of radiographic findings and with the early recognition of characteristic features, diagnosis can be made to avoid treatment delay. Although CT scan is not necessary for diagnosis, it is useful in evaluating the extent of joint destruction and guiding surgical planning. MRI can provide additional information and rule out other pathologies with similar symptoms. Overall, radiographs, CT and MRI are common modalities used in the evaluation of RDHO.

A systematic review and cross-database analysis of single nucleotide polymorphisms underlying hip morphology and osteoarthritis reveals shared mechanisms.

OBJECTIVE: Understanding the mechanisms of hip disease, such as osteoarthritis (OA), is crucial to advance their treatment. Such hip diseases often involve specific morphological changes. Genetic variations, called single nucleotide polymorphisms (SNPs), influence various hip morphological parameters. This study investigated the biological relevance of SNPs correlated to hip morphology in genome-wide association studies (GWAS). The SNP-associated genes were compared to genes associated with OA in other joints, aiming to see if the same genes play a role in both hip development and the risk of OA in other lower limb joints. METHODOLOGY: A systematic literature review was conducted to identify SNPs correlated with hip morphology, based on the Population, Intervention, Comparison, Outcome, and Study (PICOS) framework. Afterwards, Gene Ontology (GO) analysis was performed, using EnrichR, on the SNP-associated genes and compared with non-hip OA-associated genes, across different databases. RESULTS: Reviewing 49 GWAS identified 436 SNPs associated with hip joint morphology, encompassing variance in bone size, structure and shape. Among the SNP-associated genes, SOX9 plays a pivotal role in size, GDF5 impacts bone structure, and BMP7 affects shape. Overall, skeletal system development, regulation of cell differentiation, and chondrocyte differentiation emerged as crucial processes influencing hip morphology. Eighteen percent of GWAS-identified genes related to hip morphology were also associated with non-hip OA. CONCLUSION: Our findings indicate the existence of multiple shared genetic mechanisms across hip morphology and OA, highlighting the necessity for more extensive research in this area, as in contrast to the hip, the genetic background on knee or foot morphology remains largely understudied.

Reliability of Radiologic Classifications of Sequelae of Septic Arthritis of the Hip in Children.

OBJECTIVE: To the best of our knowledge, there is no study comparing the inter and intraobserver reliability of current classifications for postseptic hip sequelae in children. The current study aims to assess the interobserver and intraobserver reliability of four current classifications and identify hips that could not be classified in each classification system. METHODS: The hip radiographs of 148 consecutive children with sequelae of sepsis of the hip from 2 centers were assessed after a minimum of 2 years of follow-up after sepsis. All hips (affected and normal sides) were classified according to the 4 original descriptions of the authors of the respective classifications. If a hip did not fall into any subtype of the classification, the rater was asked to mark it as nonclassifiable and state the reason for being unable to classify the hip in the respective classification. The intraclass correlation coefficient was computed to assess the reproducibility of each classification. RESULTS: Interrater reliability and intrarater reliability were moderate (0.57 to 0.72) while including all hips. The reliability was poor (0.35 to 0.49) in all 4 classifications, with an evaluation of only affected 180 hips. A few sequelae of infection, including caput valgus (n = 7), acetabular dysplasia (4), joint space narrowing (2), and bony ankylosis (1), were not included in any of the 4 current existing classification systems. CONCLUSION: The reliability of all current classifications of sequelae of septic arthritis of the hip is moderate. A proportion of sequelae do not find a place in all current classifications. LEVEL OF EVIDENCE: Level III.

Unilateral avascular necrosis of the right hip in an HIV patient with tearing of the rectus femoris and adductor longus muscles.

A man in his 20s with a medical history of syphilis, chlamydia and HIV presented to the emergency department (ED) with 2 months of right hip pain and was found to have advanced avascular necrosis (AVN) of the right femoral head with secondary haemorrhage. The patient lacked the common risk factors of AVN in patients with HIV (PWH): ≥10 years of HIV diagnosis, extended duration on highly active antiretroviral therapy, trauma, corticosteroid use, alcohol abuse, systemic lupus erythematosus, obesity, smoking and dyslipidaemia. Given the extensive destructive changes in the hip joint and muscles, a right hip resection arthroplasty was performed, and the patient recovered well postoperatively. This case presents a learning opportunity for understanding bone pathologies in PWH and offers clinical guidance for the management of HIV-infected patients with a focus on optimising bone health.

Morphological features of the acetabulum with coxa profunda in women: a retrospective observational study.

BACKGROUND: The morphology of coxa profunda remains inadequately understood. However, knowledge about the characteristics of the acetabulum in coxa profunda can help to predict pelvic morphology in three dimensions based on radiographic findings, as well as help to diagnose and predict hip pathologies. Therefore, this study aimed to investigate the relationship between the morphological characteristics of the pelvis and coxa profunda. METHODS: We conducted a retrospective analysis including women who had undergone unilateral total hip arthroplasty. Only those with normal hip joint morphology on the opposite side, as evidenced by anteroposterior pelvic radiography showing a distance of ≥ 2 mm between the ilioischial line and acetabular floor, were included. Five parameters related to acetabular anteversion, thickness, and the position of the ilioischial line were measured using axial computed tomography at the central hip joint. The coxa profunda group (n = 39) and control group (n = 34) were compared. RESULTS: The mean acetabular anteversion angle was 12.5° ± 4° in the control group and 22.3° ± 5.6° in the coxa profunda group. The mean thickness from the acetabular fossa to the medial wall was 7.5 ± 1.7 mm in the control group and 3.9 ± 1.2 mm in the coxa profunda group. Furthermore, the bony region representing the ilioischial line was positioned more posteriorly in the coxa profunda group than it was in the control group. CONCLUSION: Our findings suggest that coxa profunda in women is associated with anterior acetabular dysplasia and a thin acetabulum, in contrast to previous interpretations of excessive coverage. This insight suggests a conversion of coxa profunda from a finding of pincer-type femoroacetabular impingement to a finding of acetabular dysplasia, a revelation that also draws attention to cup positioning for total hip arthroplasty.

Pioneering a chick embryo model to explore the intrauterine etiology of developmental dysplasia of the hip in oligohydramnios conditions.

OBJECTIVE: To explore the impact of oligohydramnios on fetal movement and hip development, given its association with developmental dysplasia of the hip (DDH) but unclear mechanisms. METHODS: Chick embryos were divided into four groups based on the severity of oligohydramnios induced by amniotic fluid aspiration (control, 0.2 mL, 0.4 mL, 0.6 mL). Fetal movement was assessed by detection of movement and quantification of residual amniotic fluid volume. Hip joint development was assessed by gross anatomic analysis, micro-computed tomography (micro-CT) for cartilage assessment, and histologic observation at multiple time points. In addition, a subset of embryos from the 0.4 mL aspirated group underwent saline reinfusion and subsequent evaluation. RESULTS: Increasing volumes of aspirated amniotic fluid resulted in worsening of fetal movement restrictions (e.g., 0.4 mL aspirated and control group at E10: frequency difference -7.765 [95% CI: -9.125, -6.404]; amplitude difference -0.343 [95% CI: -0.588, -0.097]). The 0.4 mL aspirated group had significantly smaller hip measurements compared to controls, with reduced acetabular length (-0.418 [95% CI: -0.575, -0.261]) and width (-0.304 [95% CI: -0.491, -0.117]) at day E14.5. Histological analysis revealed a smaller femoral head (1.084 ± 0.264 cm) and shallower acetabulum (0.380 ± 0.106 cm) in the 0.4 mL group. Micro-CT showed cartilage matrix degeneration (13.6% [95% CI: 0.6%, 26.7%], P = 0.043 on E14.5). Saline reinfusion resulted in significant improvements in the femoral head to greater trochanter (0.578 [95% CI: 0.323, 0.833], P = 0.001). CONCLUSIONS: Oligohydramnios can cause DDH by restricting fetal movement and disrupting hip morphogenesis in a time-dependent manner. Timely reversal of oligohydramnios during the fetal period may prevent DDH.

Utility of MRI for Patients 45 Years Old and Older With Hip or Knee Pain: A Systematic Review.

BACKGROUND. MRI utility for patients 45 years old and older with hip or knee pain is not well established. OBJECTIVE. We performed this systematic review to assess whether MRI-diagnosed hip or knee pathology in patients 45 years old and older correlates with symptoms or benefits from arthroscopic surgery. EVIDENCE ACQUISITION. A literature search (PubMed, Web of Science, Embase) of articles published before October 3, 2022, was performed to identify original research pertaining to the study question. Publication information, study design, cohort size, osteoarthritis severity, age (range, mean), measured outcomes, minimum follow-up length, and MRI field strength were extracted. Study methods were appraised with NIH's study quality assessment tools. EVIDENCE SYNTHESIS. The search yielded 1125 potential studies, of which 31 met the inclusion criteria (18 knee, 13 hip). Knee studies (10 prospective, eight retrospective) included 5907 patients (age range, 45-90 years). Bone marrow edema-like lesions, joint effusions, and synovitis on MRI were associated with symptoms. In patients with osteoarthritis, meniscal tears were less likely to be symptom generators and were less likely to respond to arthroscopic surgery with osteoarthritis progression. Hip studies (11 retrospective, two prospective) included 6385 patients (age range, 50 to ≥ 85 years). Patients with Tönnis grade 2 osteoarthritis and lower with and without femoroacetabular impingement (FAI) showed improved outcomes after arthroscopy, suggesting a role for MRI in the diagnosis of labral tears, chondral lesions, and FAI. Although this group benefited from arthroscopic surgery, outcomes were inferior to those in younger patients. Variability in study characteristics, follow-up, and outcome measures precluded a meta-analysis. CONCLUSION. In patients 45 years old and older, several knee structural lesions on MRI correlated with symptoms, representing potential imaging biomarkers. Meniscal tear identification on MRI likely has diminished clinical value as osteoarthritis progresses. For the hip, MRI can play a role in the diagnosis of labral tears, chondral lesions, and FAI in patients without advanced osteoarthritis. CLINICAL IMPACT. Several structural lesions on knee MRI correlating with symptoms may represent imaging biomarkers used as treatment targets. Osteoarthritis, not age, may play the greatest role in determining the utility of MRI for patients 45 years old and older with hip or knee pain.

Capsular attachment on the anterosuperior femoral head-neck junction: A hypothesis about femoroacetabular impingement.

Femoroacetabular impingement (FAI), characterized by a pathological contact between the proximal femur and acetabulum, is a common precursor of hip osteoarthritis. Cam morphology is a bony prominence that causes FAI and frequently forms on the anterosuperior femoral head-neck junction. Despite anatomical consensus regarding the femoral head-neck junction as a boundary area covered by the articular cartilage and joint capsule, it remains unclear whether the joint capsule is continuous with the anterosuperior articular cartilage. For the anatomical consideration of cam morphology formation, this study aimed to investigate the histological characteristics of the capsular attachment on the anterosuperior femoral head-neck junction, particularly focusing on the presence or absence of continuity of the joint capsule to the articular cartilage. A total of 21 anterosuperior regions (seven hips each for the 12:00, 1:30, and 3:00 positions) from seven hips (three males and four females; mean age at death, 68.7 years) were histologically analyzed in this study for quantitative evaluation of the capsular thickness using histological sections stained with Masson's trichrome, as well as qualitative evaluation of the capsular attachment. The present study showed that the joint capsule, which folded proximally to the femoral head-neck junction from the recess, exhibited a blend of the fibrous and synovial regions. Notably, it not only continued with the superficial layer of the articular cartilage, but also attached to the articular cartilage via the fibrocartilage. This continuous region was relatively fibrous with dense connective tissue running in the longitudinal direction. The capsular thickness at the recess point (mean, 1.7 ± 0.9 mm) and those at the distal end of the articular cartilage (0.35 ± 0.16 mm) were significantly greater than the control value for the most superficial layer thickness of the articular cartilage (0.019 ± 0.003 mm) (Dunnett's T3, both p-value <0.001). Based on the fibrous continuity between the joint capsule and articular cartilage and its thickness, this study suggests the anatomical possibility that some mechanical stress can be transmitted from the joint capsule to the articular cartilage at the frequent sites of cam morphology.