A syndrome of mental retardation, palatal defects,
micrognathia, and severe costovertebral abnormalities. Often lethal in
Smith-Theiler-Schachenmann Syndrome; Rib Gap Syndrome;
Rib Gap Defects with Micrognathia.
First described by D.W. Smith, K. Theiler, and G.
Schachenmann in 1966.
Approximately 60 cases have been described.
Familial cases with both autosomal recessive
and autosomal dominant patterns have been reported (clinically
indistinguishable). However, sporadic cases have been described, and the
disorder has been suggested to be genetically heterogeneous.
Based on clinical or radiologic findings of facial
malformations associated with severe costovertebral impairment (posterior
rib gap defects are mandatory for the diagnosis).
The disease mainly involves the head and neck
(brachycephaly, micrognathia, partial facial hypoplasia, multifocal growth
retardation involving vomer, nasoseptal cartilage, and mandibular condyles,
indicative of maxillomandibular growth arrest, short hard palate with
central defect, absent soft palate and uvula, glossoptosis, webbed neck,
posterior nuchal skin folds) and the skeleton (kyphoscoliosis, narrow rib
cage, severe costovertebral abnormalities, multiple posterior rib gap
defects filled with fibrovascular tissue resulting in flail chest, pectus
carinatum). Mental retardation, neural tube defects, absence of the
olfactory bulbs, impaired hearing, intrauterine and postnatal growth
retardation, pulmonary hypoplasia with neonatal respiratory distress, and
cardiac disease (ventricular septal defect) can be associated with this
disorder. One case was reported with hypoplastic left heart syndrome, and
another case involved omphalocele and cystic hygroma. In more than half of the
patients, death occurs in the first year of life and usually results from
Assess respiratory function
(clinically, chest radiographs, computed tomography scanning, arterial
blood gas analysis). Stridor may indicate tracheal stenosis. Evaluate the
anatomy with regard to airway management secondary to facial anomalies.
Signs and symptoms of spinal cord compression secondary to kyphoscoliosis
should be sought.
Anesthesia in this condition has not
been described. However, because the facial anomalies in these patients have
also been referred to as Pierre Robin anomaly, airway management should be expected to be
difficult. Alternative airway management techniques should be available
(e.g., fiberoptic bronchoscope, [intubating] laryngeal mask airway,
retrograde intubation) and spontaneous ventilation maintained until the
airway has been secured. Flail chest, restrictive lung disease, and tracheal
lesions predispose to perioperative respiratory complications and may result
in prolonged postoperative mechanical ventilation. Pulmonary hypoplasia and hyphoscoliasis could both
result in increased right ventricular pressures and indicate the need for echocardiography. Tracheal stenosis may require a smaller than predicted endotracheal tube. Central neuraxial
blockade should be expected to be difficult considering the vertebral
Muscle relaxants should be avoided
until the airway has been secured. Subacute bacterial endocarditis
prophylaxis may be necessary.
Pierre Robin Syndrome: A congenital syndrome with multiple etiologies
characterized by mandibular hypoplasia/aplasia. It is characterized by the
association of cleft palate, glossoptosis and micrognathia.
James PA, Aftimos S: Familial cerebro-costo-mandibular syndrome: A case