Prenatal sonographic diagnosis of clubfoot: implications for patient counseling.

This study was undertaken to determine the incidence of prenatally, sonographically diagnosed clubfoot; the incidence of associated anomalies; and the correlation with postnatal findings. Cases of prenatally diagnosed clubfeet were abstracted from a prospectively entered ultrasound database. Scans were reviewed for the presence of associated anomalies. Available neonatal charts were reviewed for correlation with prenatal findings. The incidence of prenatally diagnosed clubfoot was 0.43%. This was isolated in 33% of the cases and associated with other anomalies in 67%. All cases with associated anomalies were identified prenatally. There was a 40% false-positive rate for isolated clubfoot, all diagnosed in the third trimester of pregnancy. Prenatally diagnosed clubfoot was seen in 0.43% of this high-risk population. The correct identification of associated anomalies facilitates prenatal counseling, but limitations of prenatal ultrasound must be remembered. This information should be helpful to orthopaedic surgeons involved in the counseling of these patients.