A schematic approach to hypotonia in infancy.

Hypotonia may be the presenting sign for many systemic diseases and diseases of the nervous system. The present paper discusses a rational, simple and accurate diagnostic approach to hypotonia in infancy, illustrated by the case of a five-month-old infant girl recently referred to the IWK Health Centre in Halifax, Nova Scotia. Key points in the history and physical examination are outlined to allow a tailored investigation both for the patient and for other hypotonic infants. A discussion of an important neuromuscular disease, diagnosed in the present patient, concludes the paper.