Rotator cuff muscle atrophy grading
The Goutallier classification is a classification system used to quantify the amount of fatty degeneration of the rotator cuff muscles, particularly in the context of rotator cuff tendon tears. Although originally described in shoulder CT , it is applicable and now most commonly used in MR. It is based mainly on the percentage of atrophy and fatty degeneration of the involved muscle . The grading increases in severity and higher grades correlate with poorer function outcomes following rotator cuff tear surgical repair.
Classification
- grade 0: normal muscle
- grade 1: some fatty streaks
- grade 2: less than 50% fatty muscle atrophy
- grade 3: 50% fatty muscle atrophy
- grade 4: greater than 50% fatty muscle atrophy
It should be noted that this estimation is based on the aspect of the muscle itself and not on the space it occupies within its normal compartment. For example, the supraspinatus muscle itself can have decreased in size, occupying less than half of the supraspinatus fossa, while still being mostly muscular in content. This would correspond to a Goutallier stage 0 or 1.
The Goutallier grade is most easily assessed on non-fat saturated oblique-sagittal T1 sequences which have superior fat-to-muscle contrast.
Practical points
Increasing stage number indicates a more severe level of degeneration, with grade 3 and 4 correlated with poorer post-repair return to normal function, thus serving as a possible contraindication for surgical repair.
See also
