Prenatal Sonographic Diagnosis of Focal Musculoskeletal Anomalies

Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies. Isolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including focal limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1) ]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5) ]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2) ]; amniotic band syndrome (n=3) ; and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1) ]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) ] were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review.

Ultrasonographic Measurement of Fetal Foot Length and Femur/Foot Length Ratio in Second Trimester of Normal Pregnancy in Korean Women

PURPOSE: The aim of this study was to determine, using prenatal ultrasongraphy, normal fetal foot length and the femur length ratio during the second trimester of a normal pregnancy in Korean women. MATERIALS AND METHODS: From May to July 1999, and in September of the same year, 1018 normal Korean singleton pregnancies showing no abnormality on prenatal sonograms were included in this study. The gestational age ranged from 19 to 30 weeks. Femur and foot length were measured by one radiologist. Regression analysis was performed for foot length and gestational age, and the mean value of the femur/foot length ratio and 95th percentile confidence interval of that mean value were calculated. The data obtained was compared with that obtained from caucasians. RESULTS: Foot length correlated with gestational age (r 2=0.87, p value = 0.0001). The regression formula was as follows; Gestational age (days) = 70.98-2.15 x foot length (mm). Mean foot length at each gestational week was not different from the corresponding figure for Cancasians. The mean (+/-SD) value of the femur/foot length ratio was 0.96 (+/-0.05) and the 95th percentile confidence interval of that mean value was 0.96+/-0.000301, figures which are significantly lower than those for Caucasians. CONCLUSION: Fetal foot length during the second trimester of a normal pregnancy in Korean women is a reliable parameter for use in the assessment of gestational age. In our study the fetal foot length was not different from that of caucasians, while the femur/foot length ratio was lower than the value in that group. The nomogram depicted in of this study will serve as a useful adjunct in the screening of chromosomal abnormality or skeletal dysplasia among Koreans.

The Difference in the Appearance of Proximal Humeral Epiphyseal Ossification Center on Chest Radiograph between the preterm and Full-term Infants

PURPOSE: To assess the difference in the appearance of the proximal humeral epiphyseal ossification center, as seen on chest radiograph, between preterm and full-term infants at the same corrected ages. MATERIALS AND METHODS: Forty two preterm infants born at 26-35 weeks of gestational age and 218 normal full-term infants born at 38-42 weeks were investigated. Because of various perinatal problems, the preterm infants were treated at a neonatal intensive care unit. Proximal humeral epiphyseal ossification centers were evaluated from chest radiographs, and in cases of preterm infants, the corected age of 0 month was defined as postconceptional 40 weeks. In preterm infants, the numbers of chest radiographs obtained were 42 at 0 month, 40 at 1 month, 37 at 2 months and 36 at 3 months of corrected age, while in those who were full-term, the numbers were 103 cases at 0 month, 42 at 1 month,42 at 2 months and 31 at 3 months of age. In the preterm group, alkaline phosphatase, calcium, phosphorus levels and simple wrist radiographs were checked. We then evaluated the difference of appearance of the proximal humeral epiphyseal ossification center between preterm and full-term infants at the same corrected ages, as well as the difference between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group in preterm infants at the same corrected ages. Using Fisher's exact test, the data were analysed. RESULTS: The incidences of the proximal humeral epiphyseal ossification center in preterm infants were 2.4% (1/42) at 0 month, 20.0% (8/40) at 1 month, 43.2% (16/37) at 2 months and 69.4% (25/36) at 3 months; infull-term infants, the figures were 24.3% (25/103) at 0 month, 66.7% (28/42) at 1 month, 83.3% (35/42) at 2 months and 90.3% (28/31) at 3 months. At 0, 1, and 2 months, the incidences were thus seen to be lower in preterm than infull-term infants(p0.05). In preterm infants, there were no statistical differences between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group(p>0.05). CONCLUSION: Up to the age of two months, the proximal humeral epiphyseal ossification center of preterm infants appears later than that of full-term infants at the same corrected age.