Fatty infiltration and rotator cuff atrophy

Area of Science:

• Orthopedic Surgery
• Musculoskeletal Imaging
• Biomedical Engineering

Background:

• Rotator cuff tears frequently involve fatty infiltration and muscle atrophy, negatively impacting clinical results and repair success.
• The origins of these muscle changes are complex, involving mechanical tendon detachment and potential suprascapular nerve injury.

Purpose of the Study:

• To review the etiology, evaluation methods, and clinical associations of fatty infiltration and rotator cuff atrophy.
• To discuss the current understanding of the irreversible nature of fatty infiltration and potential for muscle atrophy reversal post-repair.

Main Methods:

• Literature review of animal and human studies on rotator cuff pathology.
• Analysis of imaging modalities (CT, MRI, ultrasonography) and staging systems (Goutallier) for assessing fatty infiltration and atrophy.
• Correlation of fatty infiltration severity with patient factors and tear characteristics.

Main Results:

• Mechanical tendon detachment is the primary cause of fatty infiltration and atrophy.
• Factors like age, tear size, retraction, massive tears, and nerve injury correlate with increased fatty infiltration.
• Fatty infiltration is irreversible, while some muscle atrophy may show slight reversal after surgical repair.

Conclusions:

• Fatty infiltration and rotator cuff atrophy are significant indicators of poor prognosis in rotator cuff tears.
• Accurate assessment via imaging and staging is crucial for patient management.
• Ongoing research into novel therapies may offer future avenues to modify the natural progression and improve outcomes.