Radiological findings in NAO syndrome.
BACKGROUND
Diseases exhibiting osteolysis in children are rare hereditary conditions. Several types have been recognised with different clinical manifestations. One type includes subcutaneous nodules, arthropathy and osteolysis and has been termed NAO syndrome. Previous radiological reports have described the affected bones, usually the carpal and tarsal regions, but a detailed analysis of the radiological findings of both the axial as well as the appendicular skeleton has not been reported.


OBJECTIVE
To describe the radiological findings in a large group of children with an autosomal recessive disease characterized by nodules, familial arthropathy and osteolysis.


METHODS
The study comprises 14 patients from 9 families and all patients had the triad of nodulosis, arthropathy and osteolysis (NAO).


RESULTS
The most common radiological manifestations were osteopenia, undertubulation of long bones, arthritic changes, sclerotic sutures of the calvaria, osteolysis and muscle contractures. Other common findings were squared vertebrae, broad medial clavicles and brachycephaly. Progress of disease was documented in more than half of the patients.


CONCLUSIONS
Our study is the first report of the detailed radiological findings of NAO syndrome. In NAO syndrome, both the axial and appendicular skeleton are involved
Al-Otaibi
Leftan
L
Department of Radiology, MBC no.28, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia. lefian@hotmail.com
Al-Mayouf
Sulalman M
SM
Majeed
Mahmoud
M
Al-Eid
Wea'am
W
Bahabri
Sultan
S
Hugosson
Claes O
CO
D000293:Adolescent; D001168:Arthritis / Q000000981:diagnostic imaging / Q000473:pathology; D001177:Arthropathy, Neurogenic / Q000000981:diagnostic imaging* / Q000473:pathology; D001851:Bone Diseases, Metabolic / Q000000981:diagnostic imaging / Q000473:pathology; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010014:Osteolysis / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography; D012529:Saudi Arabia; D013577:Syndrome