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Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Internal impingement of the shoulder
Benton E Heyworth1, Riley J Williams
1Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA. williamsr@hss.edu
The American Journal of Sports Medicine
|December 9, 2008
Summary
Internal impingement of the shoulder involves the greater tuberosity rubbing against the glenoid, often causing rotator cuff tears and labral lesions in athletes. Understanding its causes and management is key for effective treatment.
Area of Science:
- Orthopaedics
- Sports Medicine
- Biomechanics
Background:
- Internal impingement of the shoulder is a condition where the greater tuberosity contacts the glenoid during abduction and external rotation.
- This contact can lead to rotator cuff tears and glenoid labrum lesions, particularly in overhead athletes.
- The exact cause is unknown, but instability, capsular contracture, and scapular dyskinesis are suspected contributors.
Purpose of the Study:
- To review the pathomechanics, clinical presentation, and diagnostic findings of internal impingement.
- To present an overview of treatment outcomes.
- To provide a diagnostic and therapeutic algorithm for managing internal impingement.
Main Methods:
- Literature review of pathomechanics, clinical findings, and imaging.
- Review of treatment results.
- Development of a management algorithm.
Main Results:
- Internal impingement is characterized by specific contact patterns leading to rotator cuff and labral damage.
- Contributing factors may include glenohumeral instability, posterior capsular tightness, and altered scapular movement.
- A structured approach to diagnosis and treatment is proposed.
Conclusions:
- Internal impingement is a distinct pathologic entity affecting the shoulder joint.
- Multifactorial causes necessitate a comprehensive diagnostic and therapeutic strategy.
- The presented algorithm aims to guide clinicians in managing this condition effectively.
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