fetal clenched hands
Fetal clenched hands are an antenatal ultrasound observation where the fetal hands are in a constant (permanently) clenched position as if being unable to extend.
Pathology
Some authors suggest that the abnormal posture results in part from:
- muscle variations along the radial margin of the forearm and hand
- the absence of thenar muscles, anomalous tendons and attachments among the forearm groups
- fusion among the arm flexor group
Associations
Several conditions are associated with this observation which include:
- aneuploidic syndromic
- trisomy 18 / Edward syndrome: strong association
- trisomy 13 / Patau syndrome
- non aneuploidic syndromic
Radiographic features
Antenatal ultrasound
Real time images are best for assessment where the fetal hands can be directly observed in a persistent clenched position. Often there may also be overlapping fetal fingers (particularly 2 finger overlapping the 3). Its presence in an antenatal ultrasound scan is sometimes classified as a soft sign for aneuploidic anomalies.
Differential diagnosis
On antenatal imaging consider:
- fetal akinesia-hypokinesia syndromes: hand in a temporarily clenched position