Osteonecroses in childhood can be classified according to location and cause:

1. **Legg-Calvé-Perthes disease:** Necrosis of the femoral head, common in children between 4 and 10 years old.

2. **Osgood-Schlatter disease:** Necrosis of the tibial tuberosity, typical in physically active adolescents.

3. **Kienböck's disease:** Necrosis of the lunate bone in the wrist.

4. **Köhler disease I:** Necrosis of the navicular bone in the foot.

5. **Panner's disease:** Necrosis of the humeral head, especially in young athletes.

The exact causes are often not fully clarified, but various factors can contribute to the development:

• Circulatory disorders:
  • Reduced blood supply to the growth zone leads to tissue loss.
• Mechanical overload:
  • Excessive strain during sports activities can damage the vessels in the growth zone.
• Traumatic events:
  • Injuries such as falls or fractures can cause circulatory disorders.
• Systemic diseases:
  • Disorders such as sickle cell anemia or coagulation disorders increase the risk of osteonecrosis.
• Genetic predisposition:
  • Familial predisposition can increase the likelihood.

The symptoms vary depending on the affected region and stage of the disease:

- **Pain:** Load-dependent pain in the affected area, which may decrease at rest.

- **Swelling:** Local swelling, especially in the lower extremities.

- **Movement restrictions:** Reduced mobility of the affected joint, often gradually.

- **Gait changes:** Limping or protective postures in osteonecrosis of the lower extremities.

- **Muscle atrophy:** Decrease in muscle mass due to protection and reduced activity.

The diagnosis is based on a combination of medical history, clinical examination, and imaging techniques:

1. Medical History: The doctor inquires about symptoms, previous illnesses, and possible injuries.
2. Clinical Examination: Checking for tenderness, swelling, and movement restrictions in the affected area.
3. Imaging Techniques:
   • X-ray: Early stages often unremarkable, later changes in bone structure visible.
   • MRI: Highly sensitive method for detecting circulatory disorders.
   • CT: Detailed depiction of bone changes.

Conservative Therapy

In most cases, treatment can be done without surgery, especially in the early stages:

• Relief:
  • Avoidance of stressful activities through immobilization or crutches.
• Physiotherapy:
  • Exercises to strengthen muscles and promote mobility.
• Pain Therapy:
  • Use of NSAIDs to relieve pain and inflammation.
• Orthopedic Aids:
  • Insoles or orthoses for stabilization and pressure distribution.

Surgical Therapy

In advanced stages or persistent complaints, surgical intervention may be necessary:

• Corrective Osteotomy:
  • Change of bone axis to relieve the affected area.
• Drilling:
  • Promotion of blood circulation through small drill holes in the bone.
• Transplantation:
  • Replacement of necrotic tissue with bone or cartilage grafts.

To prevent osteonecrosis in childhood, the following measures can contribute:

1. Avoidance of overstrain: Regular breaks and appropriate strain during sports.
2. Early treatment of injuries: Timely care for trauma or swelling.
3. Regular exercise: Promotion of blood circulation and strengthening of muscles through gentle activities.
4. Nutritional optimization: Ensuring adequate supply of calcium and vitamin D.
5. Medical check-ups: Regular examinations for pre-existing conditions that may increase the risk.