• AI
  • Molecular Imaging
  • CT
  • X-Ray
  • Ultrasound
  • MRI
  • Facility Management
  • Mammography

External fixation devices and MRI safety

Article

Most orthopedic implants and materials do not pose problems for patients undergoing MRI procedures. MRI may be hazardous for external fixation systems, however, because of the length of the implant or the formation of a conductive loop.

Frank Shellock, Ph.D.

Adjunct clinical professor of radiology and medicine, University of Southern California and Institute for Magnetic Resonance Safety, Education, and Research

www.MRIsafety.com

www.IMRSER.org

Most orthopedic implants and materials do not pose problems for patients undergoing MRI procedures. MRI may be hazardous for external fixation systems, however, because of the length of the implant or the formation of a conductive loop.

External fixation systems are specially designed frames, clamps, rods, rod-to-rod couplings, pins, posts, fasteners, wire fixations, fixation bolts, washers, nuts, hinges, sockets, connecting bars, screws, and other components used in orthopedic and reconstructive surgery.

Indications for external fixation systems are varied, including the following treatment applications:

  • open and closed fracture fixation

  • pseudoarthroses of long bones (congenital and acquired)

  • limb lengthening by metaphyseal or epiphyseal distraction

  • correction of bony or soft-tissue defects

  • correction of bony or soft-tissue deformities

The assessment of MRI safety issues for external fixation systems is especially challenging because of the myriad possible components, many of which are made from conductive materials, and the many configurations used for these devices.

The primary concern is MRI-related heating, which is dependent on the particular aspects of the external fixation system. The specific MRI conditions - strength of the static magnetic field, radiofrequency, type of RF transmit coil, pulse sequence, body part imaged - directly affect the safety aspects of scanning patients with external fixation systems.

For each external fixation device that has undergone MRI safety testing and applied for approval of labeling from the FDA, highly specific guidelines need to be followed relative to a given device configuration and the MRI conditions used for the imaging procedure. This information will be contained in the Instructions for Use for a given external fixation device. Imaging protocols will vary accordingly.

REFERENCE

Shellock FG. Reference manual for magnetic resonance safety, implants, and devices. 2006 ed.

Recent Videos
Addressing the Early Impact of National Breast Density Notification for Mammography Reports
Where the USPSTF Breast Cancer Screening Recommendations Fall Short: An Interview with Stacy Smith-Foley, MD
A Closer Look at MRI-Guided Transurethral Ultrasound Ablation for Intermediate Risk Prostate Cancer
Improving the Quality of Breast MRI Acquisition and Processing
Can Diffusion Microstructural Imaging Provide Insights into Long Covid Beyond Conventional MRI?
Emerging MRI and PET Research Reveals Link Between Visceral Abdominal Fat and Early Signs of Alzheimer’s Disease
Nina Kottler, MD, MS
Practical Insights on CT and MRI Neuroimaging and Reporting for Stroke Patients
Related Content
© 2024 MJH Life Sciences

All rights reserved.