RadteraMRI Knee Without Contrast
MRNo contrastMSK
Indications
- Internal derangement (meniscal/ligament tear)
- ACL/PCL/collateral ligament injury
- Cartilage/chondral defect
- Patellofemoral pain
- Effusion / occult fracture / bone contusion
- Mass/cyst (Baker cyst)
Patient prep
- MRI safety screening
- Knee in dedicated extremity/knee coil
- Knee slightly flexed (~10-15°) and externally rotated ~15° to align ACL
Contrast
None / non-contrast
Technique
- Patient supine, knee centered in dedicated knee coil
- External rotation of foot helps display ACL on sagittal/oblique images
- Combination of fluid-sensitive (fat-sat PD/T2) for pathology and PD for anatomy
- Small FOV (~14-16 cm); thin slices 3-4 mm
Series / Sequences
| # | Series / Sequence | Plane | Weighting / Recon | Thickness | Notes |
|---|---|---|---|---|---|
| 1 | Sag PD fat-sat | sagittal | PD FS | 3-4 mm | Menisci, cartilage, marrow edema |
| 2 | Sag PD (or T1) | sagittal | PD | 3-4 mm | Meniscal/ligament anatomy |
| 3 | Cor T1 or PD | coronal | T1/PD | 3-4 mm | Collateral ligaments, menisci |
| 4 | Cor T2 fat-sat (or STIR) | coronal | T2 FS | 3-4 mm | Marrow edema, MCL/LCL |
| 5 | Ax PD/T2 fat-sat | axial | PD/T2 FS | 3-4 mm | Patellofemoral cartilage, retinacula |
Key points
- Fat-suppressed fluid-sensitive sequences in all three planes detect most pathology.
- Evaluate menisci primarily on sagittal/coronal; ACL on sagittal (consider oblique).
- Add contrast only for tumor/infection or MR arthrogram for postoperative meniscus/cartilage.
- Bone contusion pattern can indicate mechanism of ligament injury (pivot shift -> ACL).
References
• ACR-SSR Practice Parameter for MRI of the Knee
• Radiopaedia: Knee MRI protocol link
• ACR Appropriateness Criteria: Chronic Knee Pain
• Radiopaedia: Knee MRI protocol link
• ACR Appropriateness Criteria: Chronic Knee Pain
Source: Researched — verify against your institution
Reference template — verify and adapt to your scanner, vendor and institution before clinical use. Not a substitute for clinical judgment.