Tendon edema occurs as a result of tendon injury followed by disruption of the structured arrangement and continuity of its fibers. Tendon edema is associated with fluid accumulation and consequently, enlargement of dimensions with blurring of fiber structures.
Most tendon injuries will be accompanied by fiber edema so numerous structural changes will be correlated with the presence of edema.
In radiological assessment, edema and excessive fluid accumulation within the tendon result in increased MR signal intensity in T2 and STIR sequences.
Assessment scale of changes in corresponding MRI images:
| Normal state | Mild changes | Moderate changes | Severe changes |
| No tendon edema | Mild tendon edema | Moderate tendon edema | Severe tendon edema |
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