Related Experiment Video
Updated: Aug 24, 2026
Development of a Neonatal Rat Model for Brachial Plexus Birth Injury
Published on: March 27, 2026
Correlation between external rotation of the glenohumeral joint and deformity after brachial plexus birth palsy
1Shriners Hospital for Children, Philadelphia, Pennsylvania 19140, USA. skonzin@shrinenet.org
Insights
Physical exams can identify glenohumeral joint dysplasia in children with brachial plexus birth palsy. Loss of external rotation indicates malformation, correlating with retroversion and posterior subluxation.
Area of Science:
- Orthopedics
- Pediatric Medicine
- Radiology
Background:
- Brachial plexus birth palsy (BPBP) can lead to shoulder malformations.
- Glenohumeral joint dysplasia is a common complication in BPBP.
- Accurate assessment of shoulder structure is crucial for effective treatment.
Purpose of the Study:
- To investigate the correlation between physical examination findings and glenohumeral joint dysplasia in children with BPBP.
- To determine if clinical assessments can predict structural abnormalities in the shoulder joint.
Main Methods:
- Magnetic resonance imaging (MRI) was used to evaluate the glenohumeral joint in 33 children with residual BPBP.
- Measurements included glenoscapular angles (version) and humeral head positioning (PHHA).
- Physical examination findings, including external rotation, were recorded and correlated with MRI data.
Main Results:
- Involved shoulders showed significantly increased retroversion (average -24°) and posterior subluxation (average 28% PHHA) compared to uninvolved shoulders.
- A strong correlation (r=0.91) was found between glenoscapular version and humeral head subluxation.
- Reduced humeral head size and progressive loss of external rotation were significant indicators of shoulder malformation.
Conclusions:
- Physical examination, particularly the assessment of external rotation, can serve as an indicator of glenohumeral joint dysplasia in BPBP.
- Loss of external rotation correlates with increased retroversion and posterior subluxation, suggesting underlying malformation.
- These findings support the use of clinical assessment to identify structural shoulder abnormalities in children with BPBP.
Abstract:
The purpose of this study was to determine whether physical examination findings correlate with glenohumeral joint dysplasia after brachial plexus birth palsy. Thirty-three children with residual palsy underwent magnetic resonance imaging evaluation of both shoulders. Glenoscapular angles and humeral head measurements were calculated. Physical examination findings were recorded about the shoulder. Glenohumeral external rotation was measured during firm stabilization of the scapulothoracic joint. In the uninvolved shoulders, glenoscapular version averaged -8 degrees (range -16 degrees to -2 degrees) and percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) averaged 45% (range 34-54%). In the involved shoulders, glenoscapular version averaged -24 degrees (range -64 degrees to -7 degrees) and PHHA averaged 28% (range 0-51%). Both version and subluxation were significantly different (P < 0.001) between uninvolved and involved shoulders. There was a significant correlation between version and subluxation (r = 0.91, P < 0.001). Humeral head size was significantly less (P < 0.001) on the involved shoulder. Progressive loss of external rotation beyond neutral correlated with increased angles of retroversion and increased posterior subluxation of the humeral head and should be regarded as in indicator of shoulder malformation.
