Usefulness of a short femur in the in utero detection of skeletal dysplasias.
In 28 fetuses studied during a 4 1/2-year period, the initial femur was below 2 standard deviations (SDs) of the mean when compared with the biparietal diameter. These fetuses were considered at risk for skeletal dysplasias and were followed up. Studies were performed at a mean gestational age of 26.7 weeks (range, 15.3-41.0 weeks). Group 1 had a femur length 1-4 mm below the 2-SDs line (range, -2.0 to -4.0 SDs); no other abnormalities were detected. Interval examination of 12 femurs showed that 10 either remained shortened to the same degree or had a growth spurt. At birth, all subjects were healthy except one with mild growth retardation and one with a chromosomal abnormality. Of the two subjects that failed to continue normal growth, one was healthy and the other was a heterozygous achondroplastic dwarf. Group 2 had greater femoral shortness; all measurements were more than 5 mm below the 2-SD line (range, -4.3 to -31.0 SDs). All had fetal abnormalities and significant skeletal dysplasias. The authors conclude that the number of millimeters below the 2-SDs line is an accurate, easy criterion for evaluation of femoral length.
Department of Radiology, Jefferson Medical College and Thomas Jefferson University Hospital, Philadelphia, PA 19107.
A B
AB
Kurtz
L
L
Needleman
R J
RJ
Wapner
P
P
Hilpert
K
K
Kuhlman
P N
PN
Burns
R I
RI
Feld
D G
DG
Mitchell
S
S
Segal
L
L
Blum
D001848:Bone Diseases, Developmental / Q000000981:diagnostic imaging*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D005315:Fetal Diseases / Q000000981:diagnostic imaging; D005333:Fetus / Q000000981:diagnostic imaging*; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis; D011859:Radiography