The fetal akinesia/hypokinesia sequence (or Pena-Shokeir syndrome type I) is characterized by multiple joint contractures, facial anomalies and pulmonary hypoplasia. Whatever the cause, the common feature of this sequence is decreased foetal activity.

The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers cannot be extended to 180 degrees by either active or passive extension.