Association of distal arthrogryposis, mental retardation, whistling face, and Pierre Robin sequence: evidence for nosologic heterogeneity.

We report on 3 unrelated patients with the heterogeneous fetal hypokinesia sequence. They have distal arthrogryposis, severe developmental retardation, facial anomalies as seen in the Freeman-Sheldon syndrome ("whistling face"), and Pierre Robin sequence. The present cases show a remarkable clinical resemblance to the 3 sibs described by Illum et al. (Illum N, Reske-Nielsen E, Skovby F, Askjaer SA, Bersen A (1988): Neuropediatrics 19:186-192), where calcium deposits were found in the nervous system and skeletal muscle. The presence of severe to profound developmental retardation in the present 3 patients is equally in favour of a central nervous system abnormality as the pathogenetic basis of the fetal hypokinesia sequence with secondary facial changes and distal arthrogryposis.