Clinical characteristics and natural history of Freeman-Sheldon syndrome

Freeman-Sheldon syndrome (FSS) is a rare, multiple congenital contracture syndrome that is nonetheless relatively well-known, because affected children have a striking appearance: it was historically called "whistling-face syndrome" because of involvement of the facial muscles. FSS is often confused with other congenital contracture syndromes and, as a result, the clinical characteristics and natural history are poorly understood. The objective of this study was to analyze the presentation, natural history, and outcome of a cohort of individuals ascertained using strict diagnostic criteria for FSS.

Data from questionnaires, medical charts, examination, and photographs were analyzed to describe the physical features, therapeutic interventions, and functional outcomes in 73 individuals referred with the diagnosis of FSS.

Only 32 referred cases (approximately 40%) met diagnostic criteria for FSS. In addition to contractures, common features in these cases included severe scoliosis (85%), strabismus (42%), and hearing loss (30%). Most infants required supplementary feedings via a nasogastric (45%) or gastrostomy tube (17%). Children walked by an average age of 19 months, but approximately 80% required ambulation-assist devices. An average of approximately 10 surgeries was performed on each child, and anesthetic and/or surgical complications were reported in 50% of individuals. All individuals were cognitively normal.

The clinical characteristics and natural history of FSS distinguish it from other forms of arthrogryposis, yet FSS is frequently misdiagnosed. Children with FSS require considerable nutritional, surgical, and rehabilitative intervention. Such intensive therapeutic demands differ substantially from most other congenital contracture syndromes. These findings underscore the necessity of making an accurate diagnosis.