Collagenous degeneration of rotator cuff ± biceps tendons with proteoglycan deposition

Supraspinatus > infraspinatus > biceps > subscapularis

Diffusely thickened tendon with diffuse hypoechogenicity and indistinct fibrillar pattern

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  Graded as mild, moderate, or severe

Cortical irregularity of tendon insertional area

Biceps tendinosis usually accompanies rotator cuff tendinosis

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  Proximal end of bicipital groove is most common site of biceps tendinosis

Subclinical tendinosis of similar severity often present on opposite side

Ultrasound is better than MR for assessing tendinosis as tendon detail, such as fibrillar pattern, is better appreciated

Calcific tendinosis: Focal echogenic mass within rotator cuff tendon with acoustic shadowing

Heel-toe ultrasound probe to remove anisotropy artifact and avoid mistaking for tendinosis

Tendinosis is associated with tendon tears and should also be assessed

Tears are more linear, hypoechoic, and sharper in outline than tendinosis; may or may not be associated with volume loss of tendon contour

Suggested protocol

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  Supraspinatus: Crass (arm extended and internally rotated) or modified Crass position (hand in back pocket)

  
  
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  Infraspinatus and teres minor tendons: Arm abducted and internally rotated (hand on opposite shoulder)

  
  
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  Subscapularis and long head of biceps tendons: External rotation of arm with elbow flexed

  
  
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  Confirm all findings in 2 planes