Criteria for radiologic diagnosis of hypochondroplasia in neonates
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A radiologic diagnosis of hypochondroplasia is hampered by the absence of age-dependent radiologic criteria, particularly in the neonatal period.
To establish radiologic criteria and scoring system for identifying neonates with fibroblast growth factor receptor 3 (FGFR3)-associated hypochondroplasia.
Materials and methods
This retrospective study included 7 hypochondroplastic neonates and 30 controls. All subjects underwent radiologic examination within 28 days after birth. We evaluated parameters reflecting the presence of (1) short ilia, (2) squared ilia, (3) short greater sciatic notch, (4) horizontal acetabula, (5) short femora, (6) broad femora, (7) metaphyseal flaring, (8) lumbosacral interpedicular distance narrowing and (9) ovoid radiolucency of the proximal femora.
Only parameters 1, 3, 4, 5 and 6 were statistically different between the two groups. Parameters 3, 5 and 6 did not overlap between the groups, while parameters 1 and 4 did. Based on these results, we propose a scoring system for hypochondroplasia. Two major criteria (parameters 3 and 6) were assigned scores of 2, whereas 4 minor criteria (parameters 1, 4, 5 and 9) were assigned scores of 1. All neonates with hypochondroplasia in our material scored ≥6.
Our set of diagnostic radiologic criteria might be useful for early identification of hypochondroplastic neonates.
KeywordsAchondroplasia FGFR3 Hypochondroplasia Neonate Radiography Radiologic diagnosis Scoring system
We would like to thank the following associates for their assistance with this study: Norio Shinozuka, MD, Akinori Taguchi, MD, Hidenori Haruna MD, and Kaoru Obinata, MD. This study was supported by the NNPL Growth Hormone Award 2010 and a grant-in-aid for Scientific Research from the Ministry of Health, Labour and Welfare of Japan, H26-Nanchitou (Nan)-Ippan-055.
Compliance with ethical standards
Conflict of interest
- 1.Hicks J (2003) Achondroplasia family of skeletal dysplasia. In: The National Organization for Rare Disorders. Inc., editors. NORD guide to rare disorders. Lippincott Williams & Wilkins, Philadelphia, p 144Google Scholar
- 12.Xue Y, Sun A, Mekikian PB (2014) FGFR3 mutation frequency in 324 cases from the International Skeletal Dysplasia Registry. Mol Genet Genomic Med 2:497–503Google Scholar