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Diseases of Subchondral Bone 2
Frantz Lerebours1, Neal S ElAttrache, Bert Mandelbaum
1*Cedars-Sinai Medical Center †Kerlan Jobe Orthopedics at Cedars-Sinai, Los Angeles ‡Santa Monica Orthopaedic and Sports Medicine Group, Santa Monica, CA.
Sports Medicine and Arthroscopy Review
|May 3, 2016
Summary
Osteonecrosis of the knee is classified into three types: Spontaneous Osteonecrosis of the Knee (SONK), secondary osteonecrosis, and postarthroscopic osteonecrosis. Understanding patient factors aids in diagnosis and treatment strategies for knee osteonecrosis.
Area of Science:
- Orthopedics
- Radiology
- Pathology
Background:
- Osteonecrosis of the knee (ONK) is a condition affecting subchondral bone.
- It can manifest in distinct forms, influencing diagnostic and therapeutic approaches.
- Classifying ONK is crucial for effective patient management.
Purpose of the Study:
- To categorize the different types of osteonecrosis of the knee.
- To highlight the distinguishing features of each category.
- To emphasize the role of patient characteristics and risk factors in classification.
Main Methods:
- Review of literature on osteonecrosis of the knee.
- Analysis of patient demographics and associated risk factors.
- Comparison of clinical and radiological findings across different ONK types.
Main Results:
- Osteonecrosis of the knee is categorized into primary (Spontaneous Osteonecrosis of the Knee - SONK), secondary osteonecrosis (ON), and postarthroscopic osteonecrosis.
- SONK typically affects older women, often involving the medial femoral condyle, and is characterized by subchondral bone ischemia.
- Secondary ON usually presents in younger patients (<55 years) with multifocal bone marrow involvement extending into the metaphysis and diaphysis.
Conclusions:
- Accurate categorization of knee osteonecrosis is essential for guiding treatment decisions.
- Spontaneous Osteonecrosis of the Knee (SONK) has specific demographic and clinical features.
- Secondary and postarthroscopic osteonecrosis present distinct patterns and etiologies requiring tailored management.
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