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Updated: Aug 2, 2026
10:07
Measurement of Dynamic Scapular Kinematics Using an Acromion Marker Cluster to Minimize Skin Movement Artifact
Published on: February 10, 2015
The coracoacromial arch: MR evaluation and correlation with rotator cuff pathology
T E Farley1, C H Neumann, L S Steinbach
1San Francisco Magnetic Resonance Center, California.
Skeletal Radiology
|November 1, 1994
Summary
Rotator cuff tears show a tendency towards association with a type III acromion and significant links to thickened coracoacromial ligaments and acromioclavicular enthesophytes. The newly identified type IV acromion did not correlate with rotator cuff tears.
Area of Science:
- Orthopedics
- Radiology
- Anatomy
Background:
- Acromial morphology and associated pathologies are implicated in rotator cuff tears.
- Understanding the relationship between acromial shape, ligament status, and enthesophytes can aid diagnosis.
- Previous classifications of acromial shapes may not fully capture associations with rotator cuff pathology.
Purpose of the Study:
- To evaluate the prevalence of acromial shapes, coracoacromial ligament appearance, and acromioclavicular joint enthesophytes.
- To compare these findings in patients with and without rotator cuff tears.
- To investigate the association between these anatomical features and surgically confirmed rotator cuff tears.
Main Methods:
- Retrospective analysis of 76 patients with shoulder instability and impingement undergoing surgery.
- Comparison of surgical findings with magnetic resonance (MR) scans of 57 asymptomatic volunteers.
- Classification of acromial undersurface shapes into types I, II, III, and a newly proposed type IV.
Main Results:
- Patients with rotator cuff tears showed a tendential association with type III acromions (anteriorly hooked).
- Statistically significant associations were found between rotator cuff tears and thickened coracoacromial ligaments (17/45) and acromioclavicular enthesophytes (18/45).
- The newly classified type IV acromion (inferiorly convex) showed no recognizable association with rotator cuff tears.
Conclusions:
- Specific acromial shapes (type III) and associated pathologies like ligament thickening and enthesophytes are linked to rotator cuff tears.
- Age is a potential confounding factor in the association between acromioclavicular joint enthesophytes and rotator cuff tears.
- The type IV acromion classification may offer new insights but does not appear to be associated with rotator cuff tears.
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