Cleavage tear of the rotator cuff
Cleavage tears of the rotator cuff are delaminated rotator cuff tears characterized as horizontal intratendinous splits between the articular and bursal layers along the tendon filled with fluid.
Epidemiology
Intratendinous delaminations seem to be common in articular-sided and bursal-sided tears . They also occur in full-thickness rotator cuff tears seem to be more common in the posterior part of larger tears . Delaminated full-thickness supraspinatus tendon tears are often associated with delaminated partial-thickness tears of the infraspinatus tendon .
Clinical presentation
Clinical symptoms include shoulder pain, decreased range of motion, weakness and vary slightly with the extent of the tear similar to other rotator cuff tears.
Pathology
Different histopathological characteristics have been reported including the following :
- splits are often located between layers of different fiber orientation
- areas of necrosis next to the margins and the apex with adjacent fibrous tissue
- a synovial-like lining of the delamination in some cases
The exact pathomechanism seems not quite clear, shear stress and different strain patterns seem to play a role. Also, the articular layer seems to be more prone to retraction than the bursal sided fibers.
Location
Most intratendinous delaminations of the rotator cuff have been reported in the supraspinatus and infraspinatus tendons.
Classification
Delaminated rotator cuff tears can be classified according to their transmurality and the pattern of retraction of affected layers :
- full-thickness rotator cuff tear
- grade 1a: articular layer more medially retracted than the bursal layer
- grade 1b: bursal layer more medially retracted than the articular layer
- grade 1c: articular and bursal layer equally retracted with a horizontal split
- partial-thickness rotator cuff tear
- grade 2a: articular-sided rotator cuff tear with horizontal intratendinous split
- grade 2b: bursal-sided rotator cuff tear with horizontal intratendinous split
- grade 2c: isolated intratendinous horizontal split tear consistent with an intrasubstance tear
Radiographic features
Radiographic features of cleavage tears feature a fluid or contrast filled horizontal slit of the rotator cuff tendon and different degrees of retraction of the affected layers .
Ultrasound
Rotator cuff tears are shown as focal hypoechoic or anechoic defects on ultrasound, expected imaging findings of intratendinous delaminations and cleavage tears are associated fluid-filled horizontal slits arising from the area of the torn supraspinatus or infraspinatus tendon .
MRI
The typical finding is a linear non-transmural intrasubstance slit of fluid signal intensity of the rotator cuff on fat-saturated T2 weighted or intermediate images associated with either a full-thickness or partial-thickness rotator cuff tear .
MR/CT arthrography
MR arthrography is preferred over CT arthrography since it is also able to depict bursal-sided tears and it depicts intrasubstance tears better.
Intraarticular contrast will extend into the tear, particularly in case of an articular-sided tear.
The ABER (abduction external rotation) position is useful to demonstrate intratendinous extensions due to the lax tendon fibers and the contrast filling into the delaminated space.
Indirect MR arthrography performed after intravenous administration of a gadolinium-based contrast agent followed up with gentle movements of the shoulder for 15 min was found to have good sensitivity and specificity of 92% and 94%. In addition, it might have an advantage compared to direct MR arthrography due to enhancement of synovial lining of the split .
Radiology report
Each radiological report on a rotator cuff tear should include a description of the presence of tendon delamination and a statement about the pattern of retraction.
Treatment and prognosis
The presence of a cleavage tear or delaminated rotator cuff tear is considered to be to have a negative impact on functional and morphologic outcome after rotator cuff repair .
Indications for a surgical repair typically include recalcitrant pain and functional disability, failing to respond to conservative management .
Different surgical approaches were suggested, such as the double-row repair technique, where each layer of delaminated rotator cuff tear is sutured separately, the dual-layer suture bridge repair or the en mass suture bridge repair, where the suture is passed through the entire tendon .