Freeman-Sheldon syndrome (FSS) is a very rare, congenital contractures syndrome characterized by dysmorphic status combining bone anomalies and joint contractures with typical facies features. FSS is the most severe form of distal arthrogryposes. Approximately 100 cases have been reported in the medical literature. It affects male and female equally. Symptoms and physical findings associated with this disorder are usually present at birth and vary greatly from case to case. The three basic abnormalities are microstomia with pouting lips, camptodactyly with ulnar deviation of the hand and talipes equinovarus. Other FSS symptoms include scoliosis, H-shaped dimpling of the chin, deep nasolabial folds, and blepharophimosis. Infants with FSS may suffer from dysphagia, failure to thrive, growth deficit, and life-threatening respiratory complications due to structural anomalies of the oropharynx and upper airways. Affected people also have an increased risk of developing malignant hyperthermia; a severe reaction to certain drugs used during surgery and other invasive procedures.
The diagnosis of FSS is based on the medical history and physical examination that reveal characteristic dysmorphic status combining bone anomalies and joint contractures with typical facies features.
Mutations in the MYH3 gene, located on 17p13.1, have been identified in patients with Freeman-Sheldon syndrome.
In a study on nine patients with congenital flexion deformity of the metacarpophalangeal joint of the middle finger, Al-Harthy and Rayan (2003) included three patients with FSS.
Al-Sajee et al (2010) described an infant with FSS born to consanguineous parents. At the age of 8-days, this female child presented with dysmorphic features and seizures. The dysmorphic features included a puckered mouth, prominent forehead, low-set ears, widely spaced eyes, flat face, long philtrum, short neck and micrognathia. In addition, she had arthrogryposis of hands and bilateral talipes equinovarus. The intractable seizures needed anticonvulsants. Brain imaging studies revealed thrombotic areas and focal white matter necrosis, along with generalized mild reduction of the cerebral volume. The parents were phenotypically normal. However, three of her siblings were dysmorphic. One of them had an abnormal facies and had died at birth, while another had talipes equinovarus. At 6-months follow-up the patient was found to have delayed milestones and growth parameters. The authors speculated that the craniofacial malformations of FSS could alter cerebral morphology, resulting in a predisposition to thrombotic events.
Salati and Hussain (2013) reported a 15-month Saudi boy with Freeman-Sheldon syndrome (FSS), who was the only child after 14 years of non-consanguineous marriage. He presented with feeding difficulty, chest infection, and congenital defects. Parents faced difficulties in introducing solid foods to him. He had abnormal whistling facies including an extremely small puckered mouth; thin, pursed lips with long and well developed philtrum of upper lip, unusually prominent cheeks, and broad forehead. His eyes were widely spaced deep set with down slanting palpebral fissures and blepharosynechia. His nose was broad and saddle shaped with prominent nasal-labial folds. His ears were low set. Both of his upper limbs had camptodactyly with ulnar deviation of fingers and wrists with contracture of thumbs in adduction. There were also other significant anomalies such as: scoliosis of thoracic spine, deformed rib cage, bilateral talipes equinovarus and cryptorchidism.