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Winged scapula in patients with myotonic dystrophy type 1
Tadanori Hamano1, Tatsuro Mutoh, Mikio Hirayama
1Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Eiheiji-cho, Fukui, Japan. hamano@u-fukui.ac.jp
Neuromuscular Disorders : NMD
|June 12, 2012
Summary
This study details two myotonic dystrophy type 1 (DM1) patients with winged scapula, a rare presentation. Genetic analysis confirmed expanded CTG repeats, indicating a significant genetic basis for this muscular dystrophy manifestation.
Area of Science:
- Neurology
- Genetics
- Musculoskeletal Disorders
Background:
- Myotonic dystrophy type 1 (DM1) is a multisystem disorder.
- Winged scapula is typically associated with other neuromuscular conditions.
- The presentation of winged scapula in DM1 is uncommon.
Observation:
- Two patients from the same family presented with typical winged scapula.
- Both patients had genetically confirmed DM1 with significant CTG repeat expansions (1100 and 667 repeats).
- Muscle MRI showed notable serratus anterior muscle atrophy in both individuals.
Findings:
- Muscle biopsy revealed characteristic findings of DM1, including central nuclei and fiber size variation.
- Ragged red fibers were observed in one patient's biceps brachii muscle.
- This is the first documented report of typical winged scapula as a manifestation in DM1.
Implications:
- Highlights the phenotypic variability of myotonic dystrophy type 1.
- Suggests that winged scapula should be considered in the differential diagnosis of DM1 patients.
- Emphasizes the importance of genetic testing for DM1 in cases of unexplained winged scapula.
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