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Retroversion of the humeral head in children with an obstetric brachial plexus lesion

J A van der Sluijs1, W J R van Ouwerkerk, A de Gast

  • 1Department of Orthopaedic Surgery, Vrije Universiteit Medical Centre, Amsterdam, The Netherlands.

The Journal of Bone and Joint Surgery. British Volume
|June 5, 2002
PubMed

Insights

Infants with obstetric brachial plexus lesions (OBPL) show increased humeral retroversion in affected shoulders, particularly those over 12 months old. This finding is crucial for surgical planning in shoulder subluxation cases.

Area of Science:

  • Pediatric Orthopedics
  • Radiology
  • Neurology

Background:

  • Obstetric brachial plexus lesion (OBPL) can lead to shoulder abnormalities in infants.
  • Understanding the three-dimensional anatomy of the shoulder in OBPL is critical for effective management.

Purpose of the Study:

  • To prospectively measure humeral head retroversion in infants with OBPL using MRI.
  • To compare retroversion between affected and unaffected shoulders and analyze age-related differences.

Main Methods:

  • Prospective MRI study of 33 infants (mean age 1 year 10 months) with OBPL.
  • Standardized MRI protocol to assess glenoid and humeral retroversion in both shoulders.
  • Statistical comparison of retroversion measurements between affected and contralateral shoulders.

Main Results:

  • Significantly increased mean humeral retroversion in affected shoulders (-28.4° ± 12.5°) compared to contralateral shoulders (-21.5° ± 15.1°, p=0.02).
  • This increase was observed only in children over 12 months old.
  • In children >12 months, affected shoulders showed a mean retroversion of -29.9° ± 12.9° versus -19.6° ± 15.6° in normal shoulders (p=0.009).

Conclusions:

  • Infants with OBPL, especially those over 12 months, exhibit increased humeral retroversion.
  • This anatomical finding has significant implications for surgical considerations in shoulder subluxation associated with OBPL.
  • MRI measurement of humeral retroversion is a valuable tool in managing OBPL complications.

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