Knee and
shoulder MRI exams are the most commonly requested
musculoskeletal MRI scans. Other
MR imaging of the extremities includes
hips, ankles, elbows, and wrists. Orthopedic imaging requires very high
spatial resolution for reliable small structure definition and therefore places extremely high demands on
SNR.
Exact presentation of
joint pathology expects robust and reliable
fat suppression, often under difficult conditions like
off-center FOV,
imaging at the edge of the
field homogeneity or in regions with complex
magnetic susceptibility.
MR examinations can evaluate meniscal dislocations, muscle fiber tears, tendon disruptions, tendinitis, and diagnose bone tumors and soft tissue masses. MR can also demonstrate acute fractures that are radiographically impossible to see. Evaluation of articular cartilage for traumatic injury or assessment of degenerative disease represents an imaging challenge, which can be overcome by
high field MRI applications. Currently, fat-suppressed 3D
spoiled gradient echo sequences and
density weighted fast
spin echo sequences are the gold-standard techniques used to assess articular cartilage.
Open
MRI procedures allow the kinematic imaging of
joints, which provides added value to any
musculoskeletal MRI practice. This technique demonstrates the actual functional impingements or positional subluxations of
joints. In
knee MRI examinations, the kinematical patellar study can show patellofemoral
joint abnormalities.
See also
Open MRI,
Knee MRI,
Low Field MRI.