[Imaging and classification of avascular femoral head necrosis]

Area of Science:

• Radiology
• Orthopedic Surgery
• Medical Imaging

Background:

• Avascular femoral head necrosis (AVNFH) presents diagnostic challenges in early stages, often being clinically occult.
• Plain radiographs have limited sensitivity for early AVNFH detection, necessitating advanced imaging modalities.
• Accurate staging is crucial for guiding therapeutic decisions in adult AVNFH.

Purpose of the Study:

• To present the current diagnostic and classification status of adult AVNFH.
• To critically discuss the criteria for staging AVNFH according to the ARCO classification.
• To emphasize the role of advanced imaging in early AVNFH diagnosis.

Main Methods:

• Review of current diagnostic and classification standards for adult AVNFH.
• Discussion of imaging modalities including MRI and CT for diagnosis and staging.
• Application of the ARCO classification system for disease staging.

Main Results:

• MRI is essential for early AVNFH diagnosis and verification of clinical suspicion.
• CT may be used adjunctively with MRI in specific cases.
• Radiography remains important for follow-up and excluding other hip pathologies.

Conclusions:

• Early MRI is critical for timely AVNFH diagnosis, especially when clinical signs are subtle.
• The ARCO classification provides a standardized framework for staging adult AVNFH, guiding treatment.
• Accurate diagnosis and staging are paramount for effective management of AVNFH.