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
  • Pena-Shokeir syndrome
  • Smith-Lemli-Opitz syndrome

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

Siehe auch:

• fetal akinesia-hypokinesia syndromes

und weiter:

• Pätau-Syndrom
• Arthrogryposis multiplex congenita