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Published on: January 4, 2017
The variable position of the ear in lambdoid synostosis
John C Koshy1, Chuma J Chike-Obi, Daniel A Hatef
1Division of Plastic Surgery, Baylor College of Medicine, Houston, TX, USA.
Annals of Plastic Surgery
|October 16, 2010
Summary
Distinguishing lambdoid craniosynostosis from positional plagiocephaly is crucial for proper treatment. Ear position, previously thought to be a reliable indicator, is now found to be variable in lambdoid synostosis cases.
Area of Science:
- Pediatric Neurosurgery
- Craniofacial Surgery
- Developmental Pediatrics
Background:
- Isolated unilateral lambdoid craniosynostosis and posterior positional plagiocephaly share overlapping clinical features, complicating diagnosis.
- Traditional diagnostic criteria suggest posterior ear displacement in lambdoid synostosis and anterior displacement in positional plagiocephaly.
- Recent observations challenge this historical understanding, necessitating a re-evaluation of diagnostic markers.
Purpose of the Study:
- To investigate the reliability of ipsilateral ear position in differentiating isolated unilateral lambdoid craniosynostosis from posterior positional plagiocephaly.
- To analyze the reported ear positions in cases of unilateral lambdoid craniosynostosis in the existing literature and recent case series.
- To determine if ear position remains a significant diagnostic indicator for unilateral lambdoid craniosynostosis.
Main Methods:
- A comprehensive review of medical literature was conducted to identify cases of unilateral lambdoid craniosynostosis with reported ear positions.
- Clinical data from recent cases presenting at Texas Children's Hospital with anterior ear position and suspected lambdoid synostosis were analyzed.
- The frequency and direction of ear displacement (anterior, posterior, inferior, nondisplaced) were tabulated and analyzed.
Main Results:
- A total of 37 cases of unilateral lambdoid craniosynostosis with reported ear positions were analyzed.
- A significant proportion of cases (32%) exhibited anteriorly displaced ears, contradicting historical assumptions.
- Varied ear positions were observed, including posterior, inferior, and nondisplaced, indicating a lack of consistent diagnostic pattern.
Conclusions:
- The diagnostic significance of external ear position in isolated unilateral lambdoid craniosynostosis is currently unclear.
- Observed variations in ear position challenge the historical reliance on this feature for differentiating lambdoid synostosis from positional plagiocephaly.
- Further research is needed to identify reliable clinical markers for accurate diagnosis and appropriate management of these conditions.
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