This 49-year-old reports with left shoulder pain. You are shown a coronal proton-density fat-suppression image. An orange and pink arrow are provided to help you with your descriptors.
Q1 – What shall we name the condition? If you need a hint, think about something you might look for on a Saturday afternoon in the hardware store.
Q2 – Is this abnormality concealed or nonconcealed?
A1 – This is a PAINT lesion. PAINT stands for partial articular-sided (orange arrow) with interstitial extension (pink arrow), thus the designation PAINT lesion.
This lesion begins just medial to the rotator cuff footprint (yellow arrow) which is intact and adherent to the humeral head. On the other hand, the orange arrow sits directly over the bare area of the humerus that is devoid of cartilage. So the tear actually begins in the region of the bare area and then propagates interstitially and medially as the pink arrow.
When a tear is isolated to the articular surface or bare area, it is then known as a supraspinatus tendon articular-sided lesion (STAS). Such lesions can also occur in the infraspinatus.
A2 – It is nonconcealed. In other words, if you looked in arthroscopically, you would see this tear along the undersurface of the rotator cuff, though interstitial components of it might be more difficult to visualize interstitially without probing. Concealed tears are ones that are not visible by approach from either the bursal or the articular surface. A now famous type of interstitial tear that occurs in the footprint commonly is called a concealed interstitial delamination or CID. Occasionally, these CIDs will penetrate bone and have an irregular shape, giving them a “rim-rent” adjective descriptor.
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