ROTATOR CUFF FULL THICKNESS TEARS

SOME ANATOMY TO BEGIN: There are three surfaces to a tendon

1.  Bursal ( Pink arrow)
2. Intrasubstance ( Yellow Arrow)
3. Articular ( Orange arrow)

The Blue arrow demonstrates the subacromial/ subdeltoid bursa

WHAT IS A FULL THICKNESS TEAR:

1. We are assessing the tendon from the superior ( bursal) to its inferior ( articular) surface.
2. A full thickness tear is a tear that  involves the entire tendon in the superior to inferior direction.
3. Another way to put it is that it extends all the way between the Articular and Bursal Surfaces.

Lets break it down to the individual words

FULL THICKNESS:

1. We are assessing the tendon from its superior ( bursal) to inferior ( articular) surface.
2. The tear extends from Bursal to Articular surface of tendon.

INCOMPLETE OR LOCALISED:

1.  We are now assessing the tendon in the Anterior to Posterior direction.
2. Incomplete means, in the AP direction only a part of the tendon is torn.

COMPLETE:

1. Complete means, in the AP direction the entire tendon is torn.

If you look at the image below of the rope and imagine its the Supraspinatus Tendon

1. The first image the SST is intact and not torn.
2. The second image would be a Full Thickness Incomplete/ Localised tear ( One part of the tendon has a full thickness tear whilst the rest of the tendon is still intact).
3. The tird image would be a Full Thickness Complete Tear. ( The tendon in its entirity has a full thicknes stear.)

WHAT  TO LOOK FOR:

1. FULL THICKNESS: Look for high signal ( Fluid type) extending from bursal to articular surface of tendon ( Pink arrow in image below).
2. INCOMPLETE/ LOCALISED: Involves only a portion of the tendon ( Pink arrow). The remainder of the SST ( Blue arrow) is intact.  Orange arrow = IST

WHAT TO LOOK FOR:

1. FULL THICKNESS: Look for high signal ( Fluid type) extending from bursal to articular surface of tendon( Blue arrows in image below).
2. COMPLETE: Involves the entire SS tendon. No component of the SST is continuous and intact.  The IST ( Yellow arrow) is intact.
3. MTJ RETRACTION: With a complete, full thickness tear the musculo tendinous junction is retracted ( Pink Arrow) because the tendon is no longer attached to the greater tuberosity.

WHAT TO LOOK FOR:

4. ATROPHY +/- FATTY INFILTRATION OF THE MUSCLE.

1. Atrophy and Fatty infiltration are important to report.
2. The worse the atrophy and fatty infiltration, the less chance of a good functional outcome if surgery is performed.
3. ATROPHY: Assess on Sagittal NON Fat Sat sequence, at level of the Mercedes Sign ( see below). There is no measurement
   1. Normal SS muscle should be above the pink line.
   2. Atrophy if muscle below level of pink line.
   3. Describe as mild, moderate or severe.
4. FATTY INFILTRATION: Assess on Sagittal NON Fat Sat sequence
   1. Normal muscle belly has minimal fat ( high signal T1 or PD).
   2. Look for fat in muscle ( Orange arrow in SS and Blue arrow in IS).
   3. Varying amounts of fatty infiltration. Describe as mild, moderate, severe.