Joint fluid after aspiration. A disturbing factor in knee arthrography

Area of Science:

• Orthopedic imaging
• Radiology
• Knee arthrography

Background:

• Knee effusions can complicate arthrographic procedures.
• Assessing residual fluid volume post-aspiration is crucial for diagnostic accuracy.

Purpose of the Study:

• To quantify the average fluid volume remaining in the knee after effusion aspiration.
• To evaluate the impact of residual fluid on contrast medium dilution during knee arthrography.

Main Methods:

• Aspiration of knee effusions followed by measurement of residual fluid volume.
• Analysis of fluid volume in relation to the presence or absence of knee lesions.
• Evaluation of contrast medium dilution based on residual fluid volume.

Main Results:

• The average post-aspiration knee fluid volume was 6.8 ml.
• This fluid volume was independent of the presence of any detected knee lesion.
• Residual fluid can dilute contrast agents used in arthrography.

Conclusions:

• Residual knee fluid volume post-aspiration is consistently measurable and averages 6.8 ml.
• Dilution of contrast media by residual fluid can occur.
• Employing small volumes of high-concentration non-ionic contrast agents is advisable for optimal double-contrast knee arthrography.