12 C Syndrome
C Syndrome 609
Opitz trigonocephaly syndrome
Trigonocephaly, unusual facies, polydactyly, cardiac abnormality, cryptorchidism, limbs flexion deformi- ties
Frequency: Rare; fewer than 50 published cases.
Genetics
Possibly autosomal recessive (OMIM 211750), het- erogeneity not excluded.
Clinical Features
• Hypotonia, mental retardation
• Growth retardation
• Trigonocephaly, narrow and pointed forehead, biparietal widening
• Up-slanting palpebral fissures,epicanthus,strabis- mus, hypoplastic nasal root, low set, dysmorphic ears
• Shelf-like palate, broad alveolar ridge
• Short neck
• Congenital heart defects
• Cryptorchidism, prominent clitoris and labia majora
• Flexed elbows, wrists, fingers
• Polysyndactyly
• Central nervous system abnormalities
• Bridged palmar creases
• Redundant skin
• Vascular malformation Differential Diagnosis
• Trigonocephaly, autosomal dominant
• Trigonocephaly associated with chromosomal imbalances (del 9p, del 11q, dup13q, etc.)
Radiographic Features Skull
• Trigonocephaly
• ‘Heaped-up’ sagittal and metopic cranial sutures
• Incomplete bony fusion
• Bone defect between the orbits
• Microcephaly
C
Fig. 12.1 a, b. Patient 1, 1 year.
Micro-trigonocephaly, narrow and pointed forehead, up-slanting palpebral fissures, large nasal bridge. Note also large, low-set ears, with hypoplastic helices.
(Courtesy of Dr. O. Gabrielli, Uni- versity of Ancona, Italy)
a b
Chest
• Anomalous ribs
• Fused sternal ossification centers
• Scoliosis Extremities
• Hypoplastic metacarpals and phalanges
• Polydactyly
• Syndactyly
• Absent distal phalanges of fingers and toes
• Metaphyseal cupping of metacarpals
• Radial head dislocation
• Hip dislocation Generalized Bone Defects
• Retarded bone age
Bibliography
Antley RM, Hwang DS, Theopold W, Gorlin RJ, Steeper T, Pitt D, Danks DM, McPherson E, Bartels H, Wiedemann HR, Opitz JM. Further delineation of the C (trigonocephaly) syndrome. Am J Med Genet 1981; 9: 147–63
Lalatta F, Clerici Bagozzi D, Salmoiraghi MG, Tagliabue P, Tischer C, Zollino M, di Rocco C, Neri G, Opitz JM. “C”
trigonocephaly syndrome: clinical variability and possibil- ity of surgical treatment. Am J Med Genet 1990; 37: 451–6 Sargent C, Burn J, Baraitser M, Pembrey ME. Trigonocephaly
and the Opitz C syndrome. J Med Genet 1985; 22: 39–45 Schaap C, Schrander-Strumpel CTR, Fryns JP. Opitz-C syn-
drome: on the nosology of mental retardation and trigono- cephaly. Genet Counsel 1992; 3: 209–15
C Syndrome 610
