The vacuum arthrogram in the acutely injured knee: a case report

Area of Science:

• Radiology
• Orthopedic Trauma
• Medical Imaging

Background:

• Joint distraction during radiography can create a vacuum phenomenon.
• The presence of free fluid typically abolishes this phenomenon.
• This has led to the assumption that a vacuum phenomenon indicates the absence of serious acute injury.

Observation:

• A specific case demonstrated a vacuum arthrogram.
• This occurred despite the presence of significant acute intra-articular trauma.
• The vacuum phenomenon was observed in a context of severe injury.

Findings:

• The vacuum phenomenon can be present in cases of serious acute intra-articular trauma.
• The presence of free fluid does not always abolish the vacuum phenomenon in severe trauma.
• This challenges the established diagnostic assumption.

Implications:

• Radiologists and orthopedic surgeons should be aware of this exception.
• Relying solely on the absence of vacuum phenomenon to rule out severe trauma may be misleading.
• Further investigation may be warranted even when a vacuum phenomenon is observed in acute joint injuries.