Supraspinatus Tendinosis on MRI: Tendinopathy vs Tear

How the finding is worded

• “Mild supraspinatus tendinosis without tear”
• “Supraspinatus tendinopathy with intrasubstance signal”
• “Insertional tendinosis with a small partial-thickness articular-sided tear”
• “Tendinosis versus low-grade partial-thickness tear”

Tendinosis or tear: how the images differ

Radiologists look at how bright the signal is and where it goes. Intermediate signal that stays inside a thickened tendon fits tendinosis. Signal as bright as fluid that reaches the joint-side or bursal-side surface fits a partial-thickness tear, and signal crossing the whole tendon fits a full-thickness tear. Some patterns overlap, which is why a report may say “tendinosis versus low-grade partial tear”.

If a tear is reported, its depth and size are graded as explained in partial vs full-thickness rotator cuff tears.

Is tendinosis serious?

Rotator cuff changes become common with age, even in shoulders that do not hurt: in one MRI study of people without symptoms, 54% of those over 60 had a cuff tear. So tendinosis on a report is interpreted alongside your pain, strength and examination, and it often sits next to findings such as subacromial narrowing or bursitis.

What to ask at your follow-up

• Is this tendinosis only, or is there also a partial tear?
• How much of the tendon is involved, and is it at the insertion on the bone?
• Does the scan also show bursitis or calcium deposits?
• Which exercises or activity changes fit this finding?

Sources

1. Kjellin I, Ho CP, Cervilla V, et al. Alterations in the supraspinatus tendon at MR imaging: correlation with histopathologic findings in cadavers. Radiology. 1991;181(3):837-841.
2. Rafii M, Firooznia H, Sherman O, et al. Rotator cuff lesions: signal patterns at MR imaging. Radiology. 1990;177(3):817-823.
3. Morag Y, Jacobson JA, Miller B, et al. MR imaging of rotator cuff injury: what the clinician needs to know. Radiographics. 2006;26(4):1045-1065.
4. Sher JS, Uribe JW, Posada A, et al. Abnormal findings on magnetic resonance images of asymptomatic shoulders. J Bone Joint Surg Am. 1995;77(1):10-15.