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Brachial plexus birth injury: US screening for glenohumeral joint instability
Tiina H Pöyhiä1, Antti E Lamminen, Jari I Peltonen
1Department of Radiology, Helsinki Medical Imaging Center, Helsinki University Central Hospital, POB 281, Helsinki, FIN-00029 HUS, Finland. tiina.poyhia@hus.fi
Insights
Ultrasonography (US) effectively screens for posterior shoulder subluxation in infants with brachial plexus birth injury (BPBI). Early US screening at 3 and 6 months aids in diagnosing persistent symptoms and guiding treatment.
Area of Science:
- Pediatric Orthopedics
- Medical Imaging
- Neonatal Care
Background:
- Brachial plexus birth injury (BPBI) affects neonates, potentially leading to long-term complications.
- Posterior shoulder subluxation is a recognized complication of BPBI.
- Early detection and management are crucial for improving outcomes in infants with BPBI.
Purpose of the Study:
- To prospectively evaluate the efficacy of ultrasonography (US) for screening posterior shoulder subluxation in infants with BPBI.
- To determine the optimal timing for US screening in this population.
- To assess the correlation between US findings and clinical outcomes.
Main Methods:
- A prospective, population-based study involving neonates diagnosed with BPBI.
- Ultrasonography (US) examinations were conducted at 1, 3, 6, and 12 months of age.
- Measurements included humeral head size, ossification center, and glenohumeral joint congruency (alpha angle).
Main Results:
- BPBI occurred in 3.1 per 1000 neonates; 0.64 per 1000 had permanent injury.
- Posterior shoulder subluxation was detected by US in 9 patients with permanent BPBI (alpha angle >30 degrees).
- US detected subluxation in 55% of affected infants by 3 months and 89% by 6 months.
Conclusions:
- Ultrasonography is a valuable tool for diagnosing posterior shoulder subluxation in infants with BPBI.
- Screening the glenohumeral joint with US at 3 and 6 months is recommended for infants with persistent BPBI symptoms.
- Timely US diagnosis can aid in the management of this condition.
Purpose:
To prospectively evaluate the use and optimal timing of ultrasonographic (US) screening for posterior shoulder subluxation in infantswith brachial plexus birth injury (BPBI).
Materials And Methods:
Approval of the ethics committee and informed consent of guardians was obtained. This population-based prospective study included neonates with BPBI who were born in Helsinki from January 1, 2003 through December 31, 2006, and in whom BPBI was verified with sequential clinical examinations. US was performed at 1, 3, 6, and 12 months. Size (width and height) of the humeral head and its ossification center and congruency of the shoulder (alpha angle) were measured. Frequency of BPBI and permanent changes were evaluated. This study also included patients who were referred from the tertiary catchment area. For statistical analysis, 95% confidence intervals were calculated, and analysis of variance was performed.
Results:
BPBI was seen in 132 of 41980 neonates (3.1 per 1000). In 27 cases (0.64 per 1000), BPBI did not heal during the 1st year of life and was considered permanent. The humeral head and its ossification center were smaller on the affected side in permanent BPBI. Nine patients with permanent palsy had posterior subluxation of the humeral head depicted with US (alpha angle, >30 degrees ). In five patients, posterior subluxation [corrected] was detected at 3 months. Nineteen of 21 patients with BPBI from the tertiary catchment area had permanent palsy. Ten of 19 patients developed posterior subluxation of the shoulder, which was verified with US. Altogether, three of these cases were not detected by surgeons. Posterior subluxation of the humeral head developed during the 1st year of life in one-third of patients with permanent BPBI. In more than one-half (55% [five of nine]) of the patients, posterior subluxation [corrected] was detected with US at 3 months, and in 89% (eight of nine), it was detected at 6 months.
Conclusion:
US is a fast and useful tool for diagnosis of posterior subluxation of the humeral head, and examination of the glenohumeral joint should be performed at 3 and 6 months of age in infants with BPBI if symptoms persist.
