Congenital Hip Dislocation Radiology: Guide

Congenital hip dislocation radiology, a critical field in pediatric healthcare, significantly relies on the Pavlik harness for early-stage management and treatment monitoring. The attribute of diagnostic precision in congenital hip dislocation radiology directly influences treatment strategies, as detailed in guidelines provided by organizations such as the Radiological Society of North America (RSNA). Ultrasound, a non-invasive imaging modality, offers real-time visualization crucial for assessing hip joint stability in infants, making it indispensable in congenital hip dislocation radiology. Furthermore, the Graf classification system provides a standardized method for evaluating hip dysplasia severity using ultrasound findings, thereby guiding therapeutic interventions in congenital hip dislocation radiology.

Developmental Dysplasia of the Hip (DDH) represents a spectrum of conditions affecting the hip joint, ranging from mild instability to complete dislocation. Understanding its intricacies is paramount for healthcare professionals, as early intervention significantly improves outcomes.

This section serves as a foundational overview, setting the stage for a deeper exploration of DDH, its diagnosis, and management.

Defining Developmental Dysplasia of the Hip (DDH)

DDH encompasses a range of abnormalities in the hip joint's development. It's not a single entity but rather a spectrum.

The hip joint, ideally, functions as a stable ball-and-socket mechanism. In DDH, the acetabulum (the socket) may be shallow or misshapen, preventing the femoral head (the ball) from seating properly.

This instability can lead to a variety of issues, from subtle hip clicks to complete dislocation, impacting a child's mobility and long-term musculoskeletal health.

The Indispensable Role of Early Detection

Early detection is the cornerstone of successful DDH management. The younger the child at diagnosis, the greater the likelihood of achieving a stable, well-formed hip joint through non-surgical interventions.

Early detection enables less invasive treatments, such as the Pavlik harness. This harness gently positions the hip, encouraging proper development.

Conversely, delayed diagnosis often necessitates more complex interventions, potentially including surgery. The window of opportunity for conservative management narrows as the child grows. Therefore, vigilant screening programs and awareness among healthcare providers and parents are crucial.

A Historical Perspective on DDH Understanding

The understanding and treatment of DDH have evolved considerably over time. Historically, DDH was often diagnosed late, leading to significant disability.

Early approaches to treatment were often aggressive and yielded inconsistent results. However, advancements in imaging technology, particularly ultrasound, have revolutionized early detection.

Modern treatment strategies emphasize gentle reduction and stabilization techniques, reflecting a deeper understanding of hip joint biomechanics and development. The evolution of DDH care underscores the importance of continuous research and refinement of clinical practices. This ensures the best possible outcomes for affected individuals.

Understanding Hip Anatomy and Biomechanics in DDH

Developmental Dysplasia of the Hip (DDH) represents a spectrum of conditions affecting the hip joint, ranging from mild instability to complete dislocation. Understanding its intricacies is paramount for healthcare professionals, as early intervention significantly improves outcomes. This section serves as a foundational overview, setting the stage for a deeper exploration of hip anatomy and biomechanics as it relates to DDH.

A comprehensive understanding of the hip's structural components and biomechanical function is crucial for grasping the complexities of DDH. When typical development deviates, it can lead to instability and dysplasia. Therefore, a firm grasp of normal hip anatomy and function is essential.

The Femoral Head and Acetabulum: A Critical Relationship

The hip joint is a ball-and-socket joint, where the femoral head (the "ball") articulates with the acetabulum (the "socket") of the pelvis. This articulation is the foundation of hip stability and function.

In a normally developed hip, the acetabulum provides ample coverage of the femoral head. This coverage ensures proper weight distribution and joint stability throughout the range of motion.

In DDH, the acetabulum may be shallow or poorly formed, resulting in inadequate coverage of the femoral head. This inadequate coverage leads to instability and an increased risk of subluxation or dislocation.

The resulting abnormal biomechanics place undue stress on the joint. This can accelerate cartilage wear and potentially lead to early-onset osteoarthritis.

The Significance of the Femoral Neck

The femoral neck connects the femoral head to the femoral shaft. Its angle and length are crucial for optimal hip biomechanics.

Variations in the femoral neck angle, such as coxa valga (increased angle) or coxa vara (decreased angle), can affect hip stability and increase the risk of DDH.

An abnormal femoral neck angle alters the biomechanical forces acting on the hip joint. It compromises the efficiency of muscle action and joint loading.

These altered forces contribute to instability and abnormal acetabular development. This, in turn, worsens the dysplasia and increases the risk of dislocation.

The Role of the Labrum

The labrum is a fibrocartilaginous rim that surrounds the acetabulum. It deepens the socket and enhances hip joint stability.

The labrum acts as a seal, creating a negative pressure within the joint that further stabilizes the hip. It also protects the articular cartilage from excessive stress and impact.

In DDH, the labrum may be underdeveloped, torn, or inverted. These issues can further compromise hip joint stability and contribute to pain.

A compromised labrum loses its ability to effectively seal the joint and distribute forces. This causes increased stress on the articular cartilage and the surrounding soft tissues.

Ossification Centers and Skeletal Maturity

Ossification centers are areas within developing bones where bone formation begins. The timing and progression of ossification are critical indicators of skeletal maturity.

Delays or abnormalities in the ossification of the femoral head and acetabulum can be indicative of DDH. They can also affect treatment strategies and outcomes.

Assessing skeletal maturity through radiographic evaluation is essential for guiding treatment decisions. It ensures interventions are timed appropriately to maximize the potential for normal hip development.

Understanding the stages of skeletal maturity helps predict the hip's response to various treatments. This allows healthcare professionals to tailor interventions to optimize the outcome for each patient.

Imaging Modalities for Diagnosing DDH

Developmental Dysplasia of the Hip (DDH) represents a spectrum of conditions affecting the hip joint, ranging from mild instability to complete dislocation. Understanding its intricacies is paramount for healthcare professionals, as early intervention significantly improves outcomes.

This section explores the crucial role of imaging modalities in diagnosing DDH, outlining their respective advantages, limitations, and key measurements used in clinical practice.

Radiography (X-ray) in DDH Assessment

Radiography remains a fundamental imaging technique for DDH, particularly in older infants and children where ossification of the femoral head and acetabulum has progressed. It offers a readily available and cost-effective method for visualizing bony structures.

Key Radiographic Landmarks and Measurements

Several key radiographic landmarks and measurements are used to assess hip alignment and acetabular development. These include:

• Hilgenreiner's Line: A horizontal line drawn through the superior aspect of the triradiate cartilages. It serves as a reference point for other measurements.

• Perkin's Line: A vertical line drawn perpendicular to Hilgenreiner's Line, extending inferiorly from the acetabular roof. The femoral head should lie in the inferomedial quadrant formed by these lines.

• Shenton's Line: A continuous curved line formed by the medial border of the femoral neck and the superior pubic ramus. Disruption of this line suggests hip subluxation or dislocation.

• Acetabular Index (AI): The angle between Hilgenreiner's Line and a line drawn from the triradiate cartilage to the acetabular rim. An elevated AI indicates acetabular dysplasia.

Importance of Proper Positioning and Technique

Accurate imaging is crucial for reliable diagnosis. Proper positioning, including ensuring the pelvis is not rotated and the legs are in a neutral position, is essential. Additionally, appropriate collimation and exposure settings are vital to optimize image quality and minimize radiation exposure.

Ultrasound (Sonography) for Early Detection

Ultrasound is a valuable tool for evaluating hip stability in infants, particularly those under six months of age, as it can visualize the cartilaginous structures of the hip before they ossify.

Alpha and Beta Angles in Ultrasound Assessment

The Alpha Angle measures the degree of acetabular coverage of the femoral head. An Alpha Angle of less than 60 degrees suggests dysplasia. The Beta Angle reflects the position of the labrum and its relationship to the femoral head.

Technique and Interpretation of Ultrasound Images

The dynamic nature of ultrasound allows for real-time assessment of hip stability during stress maneuvers, such as the Barlow and Ortolani tests. Careful attention to technique and interpretation, along with the use of standardized criteria, is vital for accurate diagnosis.

Magnetic Resonance Imaging (MRI) for Advanced Assessment

MRI provides detailed visualization of soft tissues and cartilage, making it a valuable tool for assessing DDH, especially in cases where radiography and ultrasound findings are equivocal.

MRI Sequences and Protocols for DDH

Specific MRI sequences, such as T1-weighted, T2-weighted, and cartilage-sensitive sequences, are used to evaluate the morphology of the acetabulum, femoral head, and labrum. Protocols often include coronal, axial, and sagittal imaging planes to provide a comprehensive assessment of the hip joint.

Role of MRI in Treatment Planning

MRI can help determine the severity of DDH, assess the presence of labral tears or cartilage damage, and guide treatment planning, particularly in cases requiring surgical intervention.

The Multidisciplinary Team: Collaborative Care in DDH Management

Following the accurate diagnosis of DDH through appropriate imaging modalities, the journey toward effective treatment and management requires a cohesive, multidisciplinary approach. The complexity of DDH necessitates the expertise of various medical professionals working in concert to achieve the best possible outcomes for patients.

This section highlights the critical roles each specialist plays in the diagnosis, treatment, and long-term care of individuals with DDH, emphasizing the importance of collaboration and communication within the healthcare team.

Orthopedic Surgeons: The Primary Caregivers

Orthopedic surgeons are central to the diagnosis, treatment, and overall management of DDH. They possess the surgical skills and in-depth knowledge of musculoskeletal anatomy to assess the severity of the condition and determine the most appropriate course of action.

Their responsibilities encompass everything from initial clinical evaluation and diagnostic imaging interpretation to surgical intervention and post-operative rehabilitation.

Orthopedic surgeons often act as the point of contact for families, coordinating care with other specialists and providing ongoing support throughout the treatment process.

Pediatric Orthopedic Surgeons: Specialized Expertise for Children

Within the field of orthopedics, pediatric orthopedic surgeons possess specialized expertise in treating musculoskeletal conditions in children, including DDH.

Their training focuses on the unique challenges and considerations of the growing skeleton, ensuring that treatment strategies are tailored to the specific needs of each child.

Pediatric orthopedic surgeons are particularly adept at managing the non-operative and operative aspects of DDH in infants and young children, including Pavlik harness application, closed reduction techniques, and open surgical procedures when necessary.

The Vital Role of Radiologists in DDH Diagnosis

Radiologists play a crucial role in the diagnosis of DDH through their expertise in image interpretation.

Accurate and timely reporting of radiographic, ultrasound, and MRI findings is essential for guiding clinical decision-making and treatment planning.

The Importance of Accurate and Timely Reporting

Radiologists are responsible for identifying key anatomical landmarks, measuring angles and indices, and detecting subtle abnormalities that may indicate DDH.

Their reports provide crucial information about the severity of the condition, the presence of associated pathologies, and the potential for successful treatment.

Effective communication between radiologists and orthopedic surgeons is paramount for ensuring that patients receive the most appropriate and timely care.

Pediatric Radiologists: Specialized Training and Experience

Pediatric radiologists possess specialized training and experience in interpreting images of infants and children.

They are familiar with the unique imaging characteristics of the developing skeleton and are skilled at differentiating normal variations from pathological findings.

Their expertise is particularly valuable in the early diagnosis of DDH in infants, where ultrasound is often the primary imaging modality.

Musculoskeletal Radiologists: Expertise in Musculoskeletal Imaging

Musculoskeletal radiologists specialize in the imaging and interpretation of the musculoskeletal system, including bones, joints, muscles, and soft tissues.

Their expertise is particularly useful in evaluating complex cases of DDH, where advanced imaging techniques such as MRI may be required to assess the extent of cartilage damage and soft tissue involvement.

By providing detailed and accurate reports, musculoskeletal radiologists contribute to informed decision-making and improved patient outcomes.

Related Conditions and Pathologies Associated with DDH

Beyond the classic presentation of Developmental Dysplasia of the Hip (DDH), a spectrum of related conditions and pathologies can complicate diagnosis and management. Understanding these associated conditions is crucial for a comprehensive approach to patient care. This section explores the nuances of hip subluxation, acetabular dysplasia, and other contributing factors, enhancing the understanding of hip instability beyond the typical DDH framework.

Hip Subluxation: Navigating the Spectrum of Instability

Hip subluxation represents a state where the femoral head is partially displaced from the acetabulum. It's an instability that falls short of complete dislocation but still indicates abnormal hip mechanics.

The challenge with subluxation lies in its variable presentation. It may be subtle on imaging, requiring careful attention to radiographic measurements and clinical examination. Early detection and appropriate intervention are vital to prevent progression to more severe dysplasia or dislocation.

Subluxation highlights the continuum of hip instability in DDH. It serves as a reminder that even partial displacement can have long-term consequences. It reinforces the need for vigilance in monitoring at-risk infants.

Acetabular Dysplasia: Deconstructing Abnormal Acetabular Development

Acetabular dysplasia refers to an abnormality in the shape or depth of the acetabulum. This impacts its ability to adequately cover the femoral head. It's a significant factor in hip instability and a key component of DDH.

The normal acetabulum should be deep and well-formed, providing stable coverage for the femoral head. In acetabular dysplasia, the acetabulum may be shallow, oblique, or otherwise malformed, leading to inadequate support.

Types of Acetabular Dysplasia

Several types of acetabular dysplasia exist, each with unique characteristics:

• Global Dysplasia: The entire acetabulum is shallow and poorly developed.

• Posterolateral Deficiency: The posterior and lateral aspects of the acetabulum are deficient, leading to instability in these directions.

• Focal Deficiencies: Specific areas of the acetabulum are underdeveloped, creating localized instability.

The Acetabular Index: Quantifying Dysplasia

The Acetabular Index (AI) is a radiographic measurement used to quantify the degree of acetabular dysplasia. It measures the angle between Hilgenreiner's line and the acetabular roof.

An elevated AI indicates a more oblique acetabulum. This suggests greater dysplasia and increased risk of hip instability. Monitoring the AI during development helps guide treatment decisions. It also helps assess the effectiveness of interventions aimed at improving acetabular development.

Clinical Significance of Acetabular Dysplasia

Acetabular dysplasia is a primary cause of hip instability and can lead to early osteoarthritis if left untreated. The abnormal biomechanics place excessive stress on the hip joint. This causes cartilage damage and eventual joint degeneration.

Early diagnosis and treatment are essential to promote normal acetabular development and prevent long-term complications. Interventions such as the Pavlik harness or surgical reconstruction can improve hip stability. This allows the acetabulum to remodel and provide adequate coverage of the femoral head.

Treatment Strategies and Devices for DDH

Following a comprehensive diagnosis, the journey of managing Developmental Dysplasia of the Hip (DDH) pivots toward implementing targeted treatment strategies. These approaches range from non-surgical interventions designed to guide natural development, to surgical procedures aimed at correcting more severe anatomical misalignments.

This section provides a crucial overview of the various treatment options available, shedding light on their mechanisms, applications, and the factors influencing their selection. It is important to note that early and appropriate intervention is generally associated with better outcomes in DDH management.

Non-Surgical Management: Harnessing Natural Development

Non-surgical management is often the first line of treatment for infants diagnosed with DDH, particularly those under six months of age. The goal is to leverage the infant's natural growth and remodeling potential to achieve stable hip reduction.

The Pavlik Harness: A Gentle Guide

The Pavlik Harness is a dynamic orthosis that encourages hip flexion and abduction, guiding the femoral head into the acetabulum.

Its effectiveness relies on the infant's ligamentous laxity and the potential for the hip to spontaneously reduce and stabilize within the harness.

Application & Mechanism: The Pavlik harness gently positions the infant's hips in a flexed and abducted position. This encourages the femoral head to center itself within the acetabulum, promoting proper hip joint development. It's crucial that application is done by experienced medical staff, following specific guidelines.

Monitoring and Follow-Up: Regular monitoring is essential to assess harness effectiveness and skin integrity. Adjustments are made based on clinical and radiographic findings. Ultrasound imaging is commonly used in the early stages to assess hip reduction within the harness.

Potential Challenges with Pavlik Harness Treatment

While the Pavlik harness is highly effective, challenges can arise. These include harness intolerance, skin irritation, and, in some cases, failure to achieve or maintain reduction.

Careful monitoring and adjustments are required to mitigate these potential issues.

Closed Reduction: Manual Realignment

When non-surgical methods like the Pavlik harness are insufficient or when DDH is diagnosed at an older age, closed reduction may be considered.

Technique and Indications

Closed reduction involves manually manipulating the femoral head back into the acetabulum without surgical incision. This procedure is typically performed under general anesthesia to relax the surrounding muscles and facilitate gentle manipulation.

Indications for closed reduction include persistent hip instability despite Pavlik harness treatment, or when the diagnosis is made later in infancy.

Limitations and Considerations

Despite its value, closed reduction is not without limitations. Factors like the presence of soft tissue interposition or significant acetabular dysplasia can hinder successful reduction.

Moreover, there is a risk of avascular necrosis (AVN) of the femoral head, a serious complication that can compromise long-term hip health. Therefore, meticulous technique and careful patient selection are paramount.

Potential Complications of DDH and its Treatment

Following a comprehensive diagnosis, the journey of managing Developmental Dysplasia of the Hip (DDH) pivots toward implementing targeted treatment strategies. These approaches range from non-surgical interventions designed to guide natural development, to surgical procedures aimed at correcting more severe hip dislocations or dysplastic acetabula. While the goal is always to achieve a stable, well-formed hip joint, it's crucial to acknowledge the potential complications that can arise either from the condition itself or as a consequence of the interventions used to treat it. Understanding these risks, and proactively implementing strategies to mitigate them, is paramount to ensuring the best possible outcome for the patient.

One of the most concerning complications, particularly in the context of DDH treatment, is avascular necrosis (AVN) of the femoral head.

Avascular Necrosis (AVN) of the Femoral Head

Avascular Necrosis, or AVN, is a condition where the blood supply to the femoral head is disrupted, leading to bone cell death.

This can significantly impact the long-term health and function of the hip joint.

It’s important to understand that AVN can occur both as a consequence of DDH itself, or as a result of interventions used to correct it.

Risk Factors for AVN in DDH

Several factors can increase the risk of AVN in the context of DDH:

• Severity of the Initial Dislocation: More severe dislocations often require more forceful reduction maneuvers, potentially compromising blood flow.

• Age at Treatment: Infants and young children have a delicate blood supply to the femoral head, making them more vulnerable to injury during treatment.

• Method of Reduction: While both closed and open reduction techniques aim to restore normal hip anatomy, each carries a risk of disrupting the blood supply. The choice of technique and the surgeon's experience play critical roles.

• Prolonged or Excessive Pressure: Maintaining the hip in a reduced position, especially with devices like the Pavlik harness or spica cast, can sometimes exert excessive pressure on the femoral head, compromising circulation.

• Repeat Manipulations: Multiple attempts at closed reduction can increase the risk of vascular damage.

Prevention Strategies

Preventing AVN requires a multifaceted approach:

• Gentle Reduction Techniques: Employing gentle, atraumatic reduction maneuvers is crucial. Surgeons should prioritize techniques that minimize force and avoid excessive stretching of the surrounding soft tissues.

• Careful Monitoring of Hip Position: During treatment with a Pavlik harness or spica cast, it is critical to regularly monitor the position of the hip and adjust the device as needed to avoid excessive pressure on the femoral head.

• Judicious Use of Traction: In some cases, traction may be used prior to reduction to gently stretch the surrounding tissues and reduce the force required for reduction. However, traction should be applied carefully and monitored closely to avoid over-stretching.

• Prompt Recognition and Management of Complications: Any signs of vascular compromise, such as persistent pain or stiffness, should be promptly investigated and managed to minimize the risk of AVN.

Management Strategies

If AVN does occur, early and appropriate management is essential to minimize long-term damage. Management strategies may include:

• Activity Modification: Reducing weight-bearing and avoiding high-impact activities can help to protect the femoral head and promote healing.

• Physical Therapy: Physical therapy can help to maintain range of motion and strength in the hip joint.

• Bisphosphonates: These medications can help to improve bone density and reduce the risk of further bone collapse.

• Surgical Intervention: In some cases, surgical intervention may be necessary to address the AVN. Procedures may include core decompression (drilling holes into the femoral head to relieve pressure and promote blood flow), osteotomy (cutting and reshaping the bone to redistribute weight-bearing forces), or, in severe cases, hip replacement.

• Regular Monitoring with Imaging: Serial radiographs and MRI scans are essential for monitoring the progression of AVN and assessing the effectiveness of treatment.

Emphasizing Patient Safety and Long-Term Well-being

Navigating the complexities of DDH treatment requires a delicate balance between achieving a stable hip and minimizing the risk of complications. Open communication between the medical team and the family is critical. Parents should be fully informed about the potential risks and benefits of each treatment option, and their concerns should be addressed thoroughly. The goal is to empower families to make informed decisions that prioritize the long-term health and well-being of their child.

Following a comprehensive diagnosis, the journey of managing Developmental Dysplasia of the Hip (DDH) pivots toward implementing targeted treatment strategies. These approaches range from non-surgical interventions designed to guide natural development, to surgical procedures aimed at correcting more severe structural issues. However, underpinning the entire process, from initial screening to long-term management, are key concepts that significantly impact the outcome.

Key Concepts in DDH Management

Effective DDH management hinges on three fundamental pillars: Accurate Image Interpretation, Understanding Skeletal Maturity, and the unwavering importance of Early Detection. These elements are not isolated factors, but rather interconnected concepts that, when fully appreciated, enable informed decision-making and improve patient outcomes. Ignoring any of these tenets can lead to misdiagnosis, inappropriate treatment, and potentially long-term complications. Let’s delve into each of these pivotal ideas.

The Cornerstone: Accurate Image Interpretation

Image interpretation is arguably the cornerstone of DDH management. Radiographs, ultrasounds, and MRIs provide crucial visual data that inform diagnosis, guide treatment planning, and monitor progress. Inaccurate or incomplete interpretation of these images can have significant ramifications, leading to delayed or inappropriate interventions.

Mastering Radiographic Landmarks

Radiography remains a fundamental tool for DDH assessment. Mastering the key radiographic landmarks, such as Hilgenreiner's Line, Perkin's Line, and Shenton's Line, is paramount. The Acetabular Index (AI) provides a quantitative measurement of acetabular development. Accurate identification and measurement of these elements are essential for assessing hip dysplasia.

The Nuances of Ultrasound Assessment

Ultrasound plays a crucial role, particularly in infants, due to its non-invasive nature and ability to visualize cartilaginous structures. Familiarity with the Alpha and Beta angles, and understanding their significance in assessing hip stability, is critical for accurate ultrasound interpretation.

Advanced Imaging with MRI

MRI offers a detailed view of soft tissues and cartilage, providing valuable insights into the hip joint's condition. Understanding specific MRI sequences and protocols for DDH assessment is vital for utilizing this advanced imaging modality effectively.

The Role of Skeletal Maturity

Skeletal maturity plays a crucial, yet often nuanced, role in both the diagnosis and management of DDH. A child's age and stage of skeletal development significantly influence the interpretation of imaging studies and the selection of appropriate treatment strategies.

Adapting Treatment to Growth

Understanding that the hip joint undergoes significant changes as a child grows is paramount. Treatment approaches must be tailored to the child's specific stage of skeletal maturity. What might be appropriate for a neonate might be contraindicated for an older infant or child.

Ossification Centers and Their Significance

The presence and appearance of ossification centers provide valuable clues regarding skeletal age and hip development. Delayed or abnormal ossification can indicate underlying developmental issues that need to be addressed.

Long-term Considerations

Skeletal maturity must also be considered when evaluating long-term outcomes. The ultimate goal of DDH management is to achieve a stable, well-formed hip joint that will support normal function throughout the patient's life. Careful consideration of skeletal development is essential for achieving this goal.

The Imperative of Early Detection

Early detection is undeniably the cornerstone of successful DDH management. The earlier DDH is identified and addressed, the greater the likelihood of achieving optimal outcomes with less invasive interventions. Delay in diagnosis can lead to more complex and challenging treatment scenarios.

Newborn Screening Programs

Newborn screening programs play a vital role in identifying potential cases of DDH. Clinical examination, combined with selective imaging, can help identify infants at risk. These programs must be implemented effectively to ensure that all newborns receive appropriate screening.

Recognizing Risk Factors

Understanding the risk factors associated with DDH, such as breech presentation, family history, and oligohydramnios, is crucial for identifying infants who require close monitoring. Vigilance in assessing these risk factors can aid in early detection efforts.

Minimizing Long-Term Sequelae

Early intervention can significantly reduce the risk of long-term sequelae, such as hip pain, osteoarthritis, and functional limitations. By addressing DDH early, we can improve the quality of life for affected individuals and prevent the need for more extensive interventions later in life.

So, there you have it – a quick rundown of congenital hip dislocation radiology and how it helps us understand and address this condition. Hopefully, this guide has given you a clearer picture! Remember, if you're dealing with a possible case, always consult with experienced radiologists and orthopedic specialists. They're the real experts at navigating the nuances of congenital hip dislocation radiology.