Table 2.

Pycnodysostosis: Frequency of Select Features

Feature% of Persons w/Feature
Clinical Short limb, short stature~100%
Intrauterine growth restriction~30%
Brachydactyly>90%
Frontal bossing>80%
Persistently open anterior fontanelle80%
Convex nasal ridge~70%
Small jaw>70%
Midface retrusion60%
Proptosis60%
Blueish sclerae30%-40%
Obstructive sleep apnea>65%
Increased incidence of fractures~70%
Nail anomalies>50%
Dental anomalies30%-40%
Radiographic Osteosclerosis~100%
Acroosteolysis of the terminal phalanges>90%
Non-pneumatized mastoids80%
Delayed fusion of cranial sutures67%
Obtuse mandibular angle65%
Clavicular dysplasia25%

From: Pycnodysostosis

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