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In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis
07:15

In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

Published on: October 20, 2013

MRI findings of septic arthritis and associated osteomyelitis in adults

Michael Karchevsky1, Mark E Schweitzer, William B Morrison

  • 1Department of Radiology, Thomas Jefferson University Hospital, 111 S 11th St., Ste. 3390, Philadelphia, PA 19107, USA.

AJR. American Journal of Roentgenology
|December 20, 2003
PubMed
Abstract

Insights

Magnetic resonance imaging (MRI) effectively identifies septic arthritis, with synovial enhancement and edema being key indicators. Abnormal bone marrow signals on MRI are highly indicative of associated osteomyelitis.

Area of Science:

  • Radiology
  • Orthopedics
  • Infectious Diseases

Background:

  • Septic arthritis is a serious joint infection requiring prompt diagnosis.
  • Magnetic resonance imaging (MRI) offers detailed visualization of soft tissues, synovium, and bone.

Purpose of the Study:

  • To characterize the magnetic resonance imaging (MRI) findings of soft-tissue, synovial, and osseous structures in cases of septic arthritis.
  • To correlate MRI findings with clinical and microbiological data.

Main Methods:

  • Fifty consecutive septic arthritis cases were evaluated using 1.5 T MRI, including T1-weighted, T2-weighted/STIR, and contrast-enhanced sequences.
  • Observers assessed synovial enhancement, edema, effusion, fluid collections, and synovial thickening.
  • Bone marrow signal abnormalities and changes in bare areas were analyzed.
  • MRI findings were compared with clinical, microbiological, and surgical diagnoses.

Main Results:

  • High frequencies of MRI findings included synovial enhancement (98%), perisynovial edema (84%), and joint effusions (70%).
  • Bone marrow abnormalities were common, with bare area changes (86%), abnormal T2 signal (84%), and abnormal gadolinium enhancement (81%).
  • Diffuse T1 signal abnormalities in the marrow were associated with osteomyelitis.

Conclusions:

  • Synovial enhancement, perisynovial edema, and joint effusion are highly correlated with septic arthritis diagnosis.
  • A significant minority of septic arthritis cases (nearly one-third) may lack joint effusions.
  • Abnormal marrow signal, especially diffuse T1 signal changes, strongly indicates concomitant osteomyelitis.

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