Legg-Perthes-Calvé disease (MLPC)

Introduction

Legg-Perthes-Calvé disease is a pediatric orthopedic condition that affects the hip, causing significant disruption in the lives of children. This condition manifests itself as impaired blood flow to the head of the femur, the thigh bone, leading to avascular necrosis of the femoral head.

Legg-Perthes-Calvé disease can affect one or both hips, and characteristic symptoms include lameness, hip stiffness, and possibly pain, which can significantly affect the mobility and well-being of the hip. child.

Treatment of Legg-Perthes-Calvé disease primarily aims to restore vascularization of the femoral head and maintain a functional hip joint. Therapeutic approaches vary depending on the severity of the disease and may include conservative methods such as rest, the use of orthopedic appliances, osteopathy, and in some cases, surgical interventions.

Conservative measures often involve a period of rest and limitation of physical activities to allow the joint to recover. The use of orthopedic devices, such as splints or crutches, may be recommended to relieve pressure on the hip and aid the healing process. Osteopathy can also be incorporated to improve hip mobility and flexibility.

In more serious cases or when conservative approaches are not sufficient, surgical interventions may be considered. These procedures aim to restore the form and function of the femoral head, sometimes using repositioning or fixation techniques.

It is essential to emphasize that Legg-Perthes-Calvé disease can have a significant impact on the growth of the femoral head, and early management is crucial to minimize long-term complications. Regular medical monitoring is necessary to assess the progression of the disease and adjust the treatment plan accordingly.

In conclusion, Legg-Perthes-Calvé disease represents a delicate orthopedic challenge in children, requiring a multidisciplinary approach to ensure optimal recovery. Early identification, careful medical monitoring, and implementation of appropriate treatment methods are essential to mitigate the long-term effects of this condition on the health and well-being of affected children.

Impact

The incidence of Legg-Perthes-Calvé disease varies, but it is usually seen in children, most commonly between 4 and 8 years of age. Although less common, the disease can also occur earlier. Boys are affected more often than girls. Early identification and appropriate management are essential to minimize long-term complications and promote optimal recovery.

History of the discovery of Legg-Perthes-Calvé disease

Legg-Perthes-Calvé disease was described independently in 1910 by three eminent physicians: Arthur Thornton Legg, Jacques Calvé and Georg Clemens Perthes. Each of these medical pioneers has made significant contributions to the understanding of this pediatric orthopedic condition.

Arthur Thornton Legg (1874–1939) , a British surgeon, was the first to document this disease, observing its distinctive features and effects on the hip in children. His contribution to the clinical description of the disease laid the foundations for the later recognition of this condition.

Jacques Calvé (1875–1954) , a French orthopedic surgeon, also played a crucial role in the identification and characterization of Legg-Perthes-Calvé disease. His clinical observations made it possible to consolidate existing knowledge and detail the symptoms, thus contributing to a better understanding of this complex disease.

Georg Clemens Perthes (1869–1927) , a German orthopedic surgeon, also made significant contributions to the understanding of the disease that bears his name. His work laid the foundation for understanding the underlying mechanisms, particularly with a focus on the disruption of blood flow to the head of the femur.

These three physicians worked independently, but their findings and descriptions converged to establish Legg-Perthes-Calvé disease as a distinct medical entity. Their work has been crucial in raising awareness of this condition in the medical community, allowing for earlier diagnoses and advances in therapeutic approaches.

Today, Legg-Perthes-Calvé disease continues to be studied and treated thanks to the foundations laid by Legg, Calvé and Perthes. Their dedication to medical research has paved the way for advances in the understanding and management of this disease, improving the quality of life of affected children.

Demography

Stage of Legg-Perthes-Calvé disease

Stage 1

Mainly, hip pain. X-rays may show the beginning of necrosis.

Stage 2

Bone death is visible on x-ray, but the femoral head is intact.

Stage 3

Bone death is visible on x-ray, along with signs of cartilage damage and osteoarthritis.

Stage 4

The femoral head is collapsed and presents with severe osteoarthritis.

Waldenström classification

Initial

Sclerotic epiphysis with enlargement of the joint
(x-rays may not show changes until 4-6 months). Following the interruption of arterial flow at the level of the superior femoral epiphysis, the epiphyseal bone becomes necrotic. Over time, as a result of shear forces, a subchondral fracture occurs, which is often the first sign.

Fragmentation

Due to bone resorption and collapse.

Reconstruction

The necrotic bone is resorbed and gradually replaced by new bone (may last up to 18 months).

Healing

Continuous remodeling until maturity. The epiphysis is completely vascularized again, but can present significant deformations. The rest of the growth will allow the femoral head to remodel. At bone maturity, no more remodeling is possible.

A Journey Through the Stages of Legg-Perthes-Calvé Disease

Legg-Perthes-Calvé Disease (LCPD) is a complex pediatric orthopedic condition that affects the hip, causing significant disruption in children’s lives. This disease begins with a devastating process known as Avascular Necrosis (AN), where the blood supply to the femoral head is disrupted, leading to avascular necrosis of this essential region.

The first step in this complex journey is Avascular Necrosis. It is here that blood flow to the femoral head is impaired, initiating a chain of events that characterize the progression of LCPD. Deterioration of the femoral head triggers an inflammatory response, marking the onset of inflammation and pain. These two elements become the distinctive motif of the symphony of illness.

As the disease progresses, Muscle Spasms and Contractures come into play. Muscles respond to persistent pain and mechanical adjustments by contracting involuntarily, contributing to the complexity of the clinical picture. These spasms modify Joint Mechanics, altering the biomechanics of the hip joint and leaving lasting imprints.

Joint Instability becomes inevitable as the shape and structure of the femoral head undergoes changes. The joint, once stable, becomes vulnerable to instability, marking a turning point in the course of the disease. This instability leads to a Reduction in Weight Bearing on the affected hip, an attempt by the body to relieve the normal pressure placed on the painful joint.

Finally, the last stage of this journey is characterized by Secondary Modifications and Deformations. Prolonged adjustments in joint mechanics, muscular imbalances resulting from spasms, and reduction in weight carried lead to lasting changes in the hip joint, leaving visible after-effects.

This sequence forms a continuous cycle, each step being intrinsically linked to the previous one, thus creating a self-perpetuating dynamic. Breaking this complex cycle requires targeted therapeutic interventions, careful pain management, and a thorough understanding of the particularities of each individual case. Although the number of stages may vary from case to case, each child going through this complex journey of LCPD does so with nuances unique to their development. It is a journey where every step counts, where every therapeutic intervention can make a difference, offering a glimmer of hope in the management and understanding of this delicate disease.

Risk factors for Legg-Perthes-Calvé disease (MLPC)

Risk factors for Legg-Perthes-Calvé disease (LPLD) are diverse and play a crucial role in understanding this pediatric orthopedic condition. Although the exact cause of MLPC is not fully understood, several elements have been identified as potential contributors to its development.

Age is one of the main risk factors, with PCML mainly affecting children aged 2 to 12 years, with a peak incidence around 6 to 7 years of age. Boys are also more likely to be affected than girls, with an incidence ratio of around 4:1. This higher prevalence in boys remains a notable feature of the disease.

A family history of PCML is another significant risk factor. Children with family members who have known the disease are at increased risk of developing PCML themselves. This suggests a potential genetic component in predisposition to this condition.

Factors related to vascularization also play a role. Children with vascular problems, such as blood clotting disorders or circulatory problems, may be more predisposed to PCML. Additionally, environmental factors, such as passive smoking, have been studied for their association with increased risk of MLPC.

Strenuous physical activities, especially those that involve repetitive impacts on the hip, can also be triggers. Children participating in sports or high-impact physical activities may be at increased risk, although the exact relationship between physical activity and MLPC requires further study.

Early identification of these risk factors is crucial for the proactive management of MLPC. Doctors can assess family history, monitor early signs in at-risk children, and recommend adjustments in lifestyle or physical activities to reduce potential risk.

Legg-Perthes-Calvé disease is a condition that results from avascular necrosis (blood deprivation) of the femoral head, the upper part of the thigh bone. The exact causes of this condition are not always clear, but it is believed that it can be influenced by several factors, including:

1. Genetic factors: There is evidence suggesting a genetic predisposition to Legg-Perthes-Calvé disease. Some children have an increased genetic susceptibility, and there may be a family history of the disease.
2. Vascular problems: The disease is characterized by avascular necrosis of the femoral head, meaning blood flow to this area is compromised. Vascular problems, such as abnormalities in the blood supply to the hip, may contribute to the development of the disease.
3. Environmental factors: Certain environmental factors may play a role, although it is not always clear. Trauma, infections, or other environmental influences can potentially contribute to illness in some children.
4. Age: Legg-Perthes-Calvé disease usually occurs in children aged 4 to 10 years, during which bone growth is rapid. However, it can also occur in younger or older children.
5. Gender: The disease is more common in boys than girls.
6. Racial factors: Some studies have shown that Legg-Perthes-Calvé disease may be more common in Caucasian children compared to other ethnic groups.

Symptoms and warning signs in children

Early symptoms and signs play a vital role in the early identification of Legg-Perthes-Calvé disease (LPLD) in children. Although this pediatric orthopedic condition can begin insidiously, certain early indicators can alert parents and healthcare professionals to the need for a thorough evaluation.

One of the common first warning signs is limping, often seen when the child walks. Lameness may result from the pain associated with PCML, prompting the child to modify their gait to relieve discomfort at the hip. This lameness may initially be mild and intermittent, becoming more pronounced as the disease progresses.

Hip pain is a major symptom of CPML. Children may complain of pain in the hip, groin, or knee area, and this pain may be exacerbated by physical activity. Some children may also have joint stiffness, limiting their ability to perform normal hip movements.

Another sign to watch for is decreased hip mobility. Children with MLPC may experience a reduction in hip range of motion, which may be seen when flexion or extension of the leg. This limitation in mobility can contribute to lameness and difficulty in daily activities.

In some cases, early radiological signs can be detected by imaging tests such as x-rays. These signs may include changes in the shape of the femoral head, reflecting ongoing avascular necrosis. However, clinical symptoms and confirmation by imaging studies are often necessary to make a definitive diagnosis.

1. Hip or thigh pain: Children may feel pain in the hip or thigh, usually on the affected side. The pain may be mild at first and get worse over time.
2. Lameness: Children can develop lameness due to joint pain and stiffness. Lameness may be more obvious after a period of inactivity, such as getting up in the morning or after a nap.
3. Reduced mobility: There may be a decrease in the range of motion of the hip. Children may have difficulty performing normal movements such as flexion, extension, and rotation of the hip.
4. Muscle atrophy: Over time, muscle atrophy may develop in the hip area, due to limitation of physical activity caused by pain.
5. Joint stiffness: The hip may become stiff, and the child may have difficulty performing certain movements without feeling pain.
6. Tenderness to palpation: The area around the hip may be tender to touch, and palpation may trigger pain.

Pathophysiology of Legg-Perthes-Calvé disease (MLPC)

The pathophysiology of Legg-Perthes-Calvé disease (LPLD) involves a complex disruption of the vascularization process of the femoral head in growing children. This pediatric orthopedic condition usually begins with impaired blood flow to the head of the femur, the thigh bone. This vascular defect compromises the essential blood supply needed to nourish bone cells, thereby leading to progressive avascular necrosis of the femoral head.

The pathological process often begins insidiously, with a progressive decrease in vascularity to the femoral head. The absence of sufficient nutrients and oxygen triggers a cascade of cellular responses, leading to the progressive death of bone cells. The resulting avascular necrosis leads to significant structural changes in the head of the femur, altering its normal form and function.

As the disease progresses, local inflammatory reactions may occur, further worsening tissue damage. Inflammation may contribute to the pain, swelling, and reduced joint mobility seen in children with MLPC. The consequences of avascular necrosis and inflammatory changes can lead to deformity of the femoral head, thereby affecting the stability of the hip and leading to characteristic lameness.

1. Ischemia and Necrosis: MLCP usually begins with a decreased blood supply to the head of the femur, leading to ischemia (lack of blood supply) in this region. Decreased blood flow can lead to avascular necrosis, where bone tissue gradually dies due to lack of oxygen and nutrients.
2. Repair and Remodeling: In response to necrosis, the body attempts to repair damaged bone tissue. This can lead to the formation of new bone tissue and remodeling of the head of the femur. However, this repair process may not proceed uniformly, leading to deformities of the femoral head.
3. Inflammation and Pain: Necrosis and the repair process can cause an inflammatory reaction in the affected area. Inflammation contributes to pain and other symptoms associated with MLCP.
4. Growth Impairments: MLCP commonly occurs in growing children, and the disease can affect normal growth of the femur. Growth alterations can lead to permanent deformities of the femoral head and hip joint.

Early diagnosis: why is it crucial in this disease?

Early diagnosis of Legg-Perthes-Calvé disease is crucial due to several factors that can influence treatment and long-term outcomes. Here are some reasons why early diagnosis is important in this disease:

1. Early intervention to prevent permanent deformity: Legg-Perthes-Calvé disease can lead to permanent deformities of the femoral head and hip joint. Early intervention, usually through conservative or surgical means, can help minimize these deformities and preserve normal joint function.
2. Promotion of normal growth: Legg-Perthes-Calvé disease usually occurs in growing children. Early diagnosis allows doctors to implement treatment strategies that aim to support normal growth of the femoral head and minimize disruptions in bone development.
3. Reduced risk of complications: Early treatment can help reduce the risk of complications associated with the disease, such as early arthritis. By intervening quickly, we can minimize the long-term deleterious effects on the hip joint.
4. Improved quality of life: By identifying Legg-Perthes-Calvé disease early and implementing an appropriate treatment plan, we can improve the child’s quality of life. This includes pain management, preservation of mobility and reduction of psychosocial impacts linked to the disease.
5. Possibility of less invasive treatments: In some cases, early diagnosis may allow for less invasive and more conservative treatments, which may be beneficial, particularly in young, growing children.

Differential diagnostics

1. Juvenile idiopathic arthritis (JIA): JIA is a chronic inflammation of the joints that can also affect children. It may present with similar symptoms, such as joint pain and stiffness.
2. Joint infection: An infection of the joint, such as osteomyelitis or septic arthritis, can cause symptoms similar to PCML.
3. Blood clotting disorders: Certain clotting disorders can cause problems with vascularization, leading to avascular necrosis. These disorders must be considered in the differential diagnosis.
4. Bone tumors: Although rare in children, some bone tumors can affect the head of the femur and cause symptoms similar to MLCP.
5. Hip Dysplasia: Developmental abnormalities of the hip, such as hip dysplasia, may present with similar symptoms and require differential evaluation.

Treatment Options for Legg-Perthes-Calvé Disease

Treatment for Legg-Perthes-Calvé disease depends on several factors, including the stage of the disease, the age of the child, and the severity of the symptoms. Treatment options can be divided into conservative and surgical approaches. It is important to note that treatment must be personalized according to the specific characteristics of each case. Here is an overview of treatment options:

Conservative approaches

1. Rest and activity restriction: Particularly during the early stages of the disease, it may be recommended to limit physical activities and allow the hip to rest to reduce pressure on the femoral head.
2. Osteopathy: Osteopathy exercises may be prescribed to improve hip mobility, strengthen surrounding muscles and promote proper posture.
3. Orthotics: The use of orthotics, such as splints or casts, may be recommended to stabilize the hip and reduce the load on the femoral head.
4. Anti-inflammatory medications: Nonsteroidal anti-inflammatory medications (NSAIDs) may be prescribed to reduce pain and inflammation.

Surgical approaches

1. Osteotomy: This surgical procedure aims to reshape the bone to restore the normal shape of the femoral head. Different types of osteotomies may be considered depending on the specific characteristics of the disease.
2. Epiphysiolysis: This is a surgical procedure aimed at decompressing the femoral head and improving vascularization by removing part of the bone.
3. Resection or debridement: In some cases, surgery may be necessary to remove deformed or necrotic bone fragments.
4. Hip replacement: In severe cases and in adults, hip arthroplasty (hip replacement) may be considered.

Frequently asked questions about Legg-Perthes-Calvé disease

1. What is Legg-Perthes-Calvé disease?
   • Legg-Perthes-Calvé disease is a condition that involves avascular necrosis of the femoral head, usually in children.
2. What are the symptoms of Legg-Perthes-Calvé disease in children?
   • Symptoms include hip pain, lameness, reduced mobility, and sometimes tenderness to palpation.
3. What are the risk factors for Legg-Perthes-Calvé disease?
   • Risk factors include genetic predispositions, vascular problems, environmental factors, young age, male gender and particular ethnic origin.
4. Why is early diagnosis important in Legg-Perthes-Calvé disease?
   • Early diagnosis allows appropriate treatment to be initiated in the early stages of the disease, which can help prevent complications and minimize long-term after-effects.
5. What are the radiographic signs of Legg-Perthes-Calvé disease?
   • Radiographic signs include avascular necrosis, bone fragmentation, joint space reduction, callus formation, joint deformities, crescent sign, and osteophytes.
6. What are the treatment options for Legg-Perthes-Calvé disease?
   • Options include rest, physical therapy, orthotics, anti-inflammatory medications, osteotomy, epiphysiolysis, resection, debridement, and sometimes hip arthroplasty.
7. Which healthcare professional should I see if I suspect my child has Legg-Perthes-Calvé disease?
   • Consult a pediatrician, who can refer to a pediatric orthopedist for specialized evaluations and recommendations.
8. How is the disease monitored and treated over time?
   • Follow-up includes regular x-rays to assess disease progression. Treatment can be adjusted depending on the evolution of the child’s condition.
9. What are the expected results with the treatment of Legg-Perthes-Calvé disease?
   • Results vary, but early diagnosis and appropriate treatment can help minimize after-effects, preserve joint function and improve quality of life.
10. Can Legg-Perthes-Calvé disease affect adults?
    • Although the disease is more common in children, it can sometimes affect adults. Treatment may differ depending on age and severity of the disease.

Radiographic signs

Radiographic signs of Legg-Perthes-Calvé disease are usually observed using medical imaging tests, such as x-rays. These signs may change over time as the disease progresses. Here are some of the characteristic radiographic signs of Legg-Perthes-Calvé disease:

1. Avascular necrosis: Decreased bone density of the femoral head due to avascular necrosis.
2. Bone fragmentation: Presence of bone fragments detached from the femoral head.
3. Joint space reduction: Decrease in the space between the femoral head and the acetabulum.
4. Bone callus formation: Development of bone callus in response to necrosis and bone fragmentation.
5. Joint deformities: Changes in the shape of the femoral head and acetabulum.
6. Crescent sign: Crescent-shaped bony condensation located in the superior and anterior region of the femoral head, seen in advanced stages of the disease.
7. Osteophyte: Formation of additional bony growths, often seen in areas affected by Legg-Perthes-Calvé disease.

Conclusion

In conclusion, Legg-Perthes-Calvé disease represents a complex pediatric orthopedic condition that was first identified and described in the early 20th century by physicians Arthur Thornton Legg, Jacques Calvé, and Georg Clemens Perthes. Their dedication to medical research has laid the foundation for understanding this condition, enabling earlier diagnoses and significant advances in therapeutic approaches.

This disease, characterized by disruption of blood flow to the head of the femur, can lead to avascular necrosis, thereby affecting the growth and development of the thigh bone. It occurs most often in children between 4 and 8 years old, with a predominance in boys.

Treatment of Legg-Perthes-Calvé disease aims to restore vascularization of the femoral head and maintain a functional hip joint. Therapeutic approaches include rest, the use of orthopedic appliances, osteopathy, and in some cases, surgical interventions.

The story of the discovery of this disease is a testament to the importance of international medical collaboration in understanding pediatric conditions. Thanks to the contributions of Legg, Calvé and Perthes, Legg-Perthes-Calvé disease is now better understood, which facilitates early diagnosis and appropriate treatment.

Although the disease can present significant challenges, including impacts on femoral head growth and long-term complications, early and appropriate management can minimize these effects and promote optimal recovery. Continuing research in the field of pediatric orthopedics aims to further improve treatment options and optimize the quality of life of children affected by Legg-Perthes-Calvé disease.

Questionnaire 1

1. Who first described Legg-Perthes-Calvé disease?
   has. Arthur Thornton Legg
   b. Jacques Calvé
   v. Georg Clemens Perthes
   d. All previous answers
2. What is the main characteristic of Legg-Perthes-Calvé disease?
   has. Avascular necrosis of the femoral head
   b. Early arthritis
   c. Bone fragmentation
   d. Joint space reduction
3. At what age does Legg-Perthes-Calvé disease usually appear in children?
   has. 1-3 years
   b. 4-8 years
   c. 9-12 years
   d. 13-16 years old
4. What is the main goal of treatment for Legg-Perthes-Calvé disease?
   has. Relieve pain
   b. Restore vascularization of the femoral head
   c. Minimize lameness
   d. All previous answers
5. What are the stages of Legg-Perthes-Calvé disease?
   has. Initial stage, fragmentation, reconstruction, healing
   b. Stage 1, stage 2, stage 3, stage 4
   c. Initial, fragmentation, reconstruction, healing
   d. Pain, stiffness, inflammation, deformation
6. What is the role of osteopathy in the treatment of disease?
   has. Strengthen muscles
   b. Improve mobility
   c. Facilitate the healing process
   d. All previous answers
7. What is the characteristic radiographic sign seen in advanced stages of Legg-Perthes-Calvé disease?
   has. Avascular necrosis
   b. Bone fragmentation
   c. Crescent sign
   d. Joint space reduction
8. What are the risk factors for Legg-Perthes-Calvé disease?
   has. Age
   b. Gender
   c. Heredity
   d. All previous answers
9. Why is early diagnosis crucial in Legg-Perthes-Calvé disease?
   has. To avoid permanent deformation
   b. To promote normal growth
   c. To reduce the risk of complications
   d. All previous answers
10. What is the main consequence of Legg-Perthes-Calvé disease on the femoral head?
    has. Osteophytes
    b. Avascular necrosis
    c. Bone fragmentation
    d. Joint space reduction

Here are the possible answers for each question:

1. Who first described Legg-Perthes-Calvé disease? Answer: d. All previous answers (Arthur Thornton Legg, Jacques Calvé, Georg Clemens Perthes)
2. What is the main characteristic of Legg-Perthes-Calvé disease? Respond to. Avascular necrosis of the femoral head
3. At what age does Legg-Perthes-Calvé disease usually appear in children? Answer: c. 9-12 years old
4. What is the main goal of treatment for Legg-Perthes-Calvé disease? Answer: d. All of the above (Relieve pain, restore vascularity, minimize lameness)
5. What are the stages of Legg-Perthes-Calvé disease? Answer: c. Initial, fragmentation, reconstruction, healing
6. What is the role of osteopathy in the treatment of disease? Answer: d. All previous answers (Strengthen muscles, improve mobility, facilitate the healing process)
7. What is the characteristic radiographic sign seen in advanced stages of Legg-Perthes-Calvé disease? Answer: c. Crescent sign
8. What are the risk factors for Legg-Perthes-Calvé disease? Answer: d. All previous answers (Age, gender, heredity)
9. Why is early diagnosis crucial in Legg-Perthes-Calvé disease? Answer: d. All of the above (Avoid permanent deformity, promote normal growth, reduce risk of complications)
10. What is the main consequence of Legg-Perthes-Calvé disease on the femoral head? Answer: b. Avascular necrosis

Questionnaire

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