A comparative analysis of fatty infiltration and muscle atrophy in patients with chronic rotator cuff tears and suprascapular neuropathy

Silvan Beeler, Eugene TH Ek, Christian Gerber

Research output: Contribution to journalArticleResearchpeer-review

43 Citations (Scopus)

Abstract

Background: Little is known of the mechanisms that lead to the muscle changes associated with rotator cuff disorders. We have observed that the magnetic resonance imaging (MRI) appearance of fatty infiltration (FI) and muscle atrophy (MA) differ between chronic cuff tears and suprascapular neuropathy, suggesting different pathophysiology. This study compares the different MRI changes that occur in chronic cuff tears and suprascapular neuropathy. Methods: Two groups were retrospectively identified: (1) RCT group (20 shoulders): patients with chronic tears of the supraspinatus and/or infraspinatus without electromyographic (EMG) evidence of suprascapular neuropathy; (2) neuro group (17 shoulders): patients with EMG documented suprascapular nerve dysfunction and absence of a rotator cuff tear. Magnetic resonance arthrograms were analyzed for the degree of FI and MA, and the morphology of the muscle was assessed, in particular the muscle border, pattern of FI, and extent of involvement. Results: The muscle changes that occur following chronic cuff tears differ from that following denervation secondary to suprascapular neuropathy, especially with respect to the muscle border, degree of perineural fat, and overall distribution of FI. Highly specific and characteristic morphological patterns of FI exist for both chronic cuff tears and suprascapular neuropathy. Conclusion: Chronic rotator cuff tendon tears and suprascapular neuropathy are both associated with FIand MA of the rotator cuff muscles. The pattern of FI is markedly different in the 2 situations. These findings have diagnostic potential and may serve as a basis for further research concerning type, severity, and evolution of FI under different conditions and after treatment.
Original languageEnglish
Pages (from-to)1537 - 1546
Number of pages10
JournalJournal of Shoulder and Elbow Surgery
Volume22
Issue number11
DOIs
Publication statusPublished - 2013

Cite this