Magnetic resonance histologic correlation in rotator cuff tendons

Area of Science:

• Musculoskeletal imaging
• Orthopedic pathology
• Radiology

Background:

• Rotator cuff tendon pathology is common.
• Magnetic resonance imaging (MRI) is crucial for diagnosing rotator cuff abnormalities.
• Understanding the correlation between histology and MRI appearance is vital for accurate diagnosis.

Purpose of the Study:

• To correlate specific histologic changes in rotator cuff tendons with their appearance on various magnetic resonance imaging (MRI) sequences.
• To investigate the signal characteristics of mucoid degeneration and chondroid metaplasia on T1-weighted, T2-weighted fat-suppressed, and proton density-weighted fat-suppressed MRI.

Main Methods:

• Acquisition of T1-weighted, fat-suppressed T2-weighted, and fat-suppressed proton density-weighted MRI sequences from 18 cadaveric shoulders.
• Histological evaluation of supraspinatus, infraspinatus, and subscapularis tendons.
• Independent blinded evaluation of regions of interest (ROIs) by two musculoskeletal radiologists.

Main Results:

• Mucoid degeneration and chondroid metaplasia were the most common histologic abnormalities found in rotator cuff tendons.
• Mucoid degeneration demonstrated hyperintensity on T2-weighted fat-suppressed and proton density-weighted fat-suppressed images compared to normal tendon.
• Chondroid metaplasia showed hyperintensity across all evaluated MRI sequences compared to normal tendon.

Conclusions:

• Chondroid metaplasia is a more prevalent finding in rotator cuff tendons than previously recognized.
• Both mucoid degeneration and chondroid metaplasia can contribute to increased signal intensity observed on rotator cuff MRI.
• These histologic-imaging correlations aid in the interpretation of rotator cuff MRI findings.