Intrasubstance tear
Intrasubstance rotator cuff tears are referred to as concealed partial-thickness rotator cuff tear neither extending to the articular nor the bursal side of the rotator cuff.
Terminology
Intrasubstance tears are also known as concealed interstitial delaminations (CID) .
Epidemiology
According to cadaver studies they are the most common form of partial-thickness rotator cuff tear.
Pathology
Intrasubstance tears are confined to the tendon substance and bursal as well as articular side appear normal at arthroscopy .
Location
Intrasubstance tears are most commonly found in the posterior supraspinatus tendon .
Radiographic features
Intrasubstance rotator cuff tears are difficult to detect.
Ultrasound
On ultrasound, a focal hypoechoic or anechoic slit of the rotator cuff within the tendon substance might be seen.
MRI
A typical finding is a linear non-transmural intrasubstance slit of fluid signal intensity of the rotator cuff on fat-saturated T2- weighted or intermediate-weighted images with intact articular-sided and bursal-sided fibers.
MR/CT arthrography
CT arthrography will not depict an intrasubstance rotator cuff tear since per definition it is concealed. MR arthrography should not have any additional advantage over MRI unless to prove the suspected tear is not a partial articular tear with intratendinous extension or PAINT lesion.
See also
