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Updated: Aug 6, 2026
10:07
Measurement of Dynamic Scapular Kinematics Using an Acromion Marker Cluster to Minimize Skin Movement Artifact
Published on: February 10, 2015
Acromial morphotype in the young asymptomatic athletic shoulder
K P Speer1, D C Osbahr, B J Montella
1Division of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA. kspeer@nc.rr.com
Journal of Shoulder and Elbow Surgery
|October 20, 2001
Summary
The type III acromion is rare in young, asymptomatic athletes. This suggests that observed higher rates in older individuals may be due to secondary acromial changes, not innate anatomy.
Area of Science:
- Orthopedics
- Radiology
- Sports Medicine
Background:
- An association between type III acromion and rotator cuff tears is documented.
- Controversy exists regarding whether acromial shape is an innate characteristic.
Purpose of the Study:
- To evaluate the prevalence of type III acromion in young, asymptomatic athletes.
- To investigate potential secondary changes contributing to acromial morphology.
Main Methods:
- Obtained bilateral supraspinatus outlet radiographs in 100 Division 1 collegiate athletes (average age 19.9 years).
- Classified acromial types using the Bigliani subjective classification and objective measurement criteria.
Main Results:
- Only 4% (2%) of shoulders exhibited type III acromion by subjective classification.
- 4% (8%) of acromia were type III by objective criteria.
- Type III acromion is rare in asymptomatic young athletes.
Conclusions:
- The low incidence in young athletes suggests type III acromion may not be solely an innate characteristic.
- Higher prevalence in older populations might be linked to secondary acromial changes.
- Further research is needed to understand incidence in the general population.
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