Paediatrics: Cleidocranial dysplasia

Cleidocranial dysplasia

Also known as cleidocranial dysostosis. Characterized by deficient ossi-fication of the clavicle (cleido) and bones of skull (cranial). It is a rare congenital autosomal dominant condition.

Clinical features

• General: proportionate mild short stature. No mental retardation.

• Cranium: large skull, frontal and parietal bossing, delayed imperfect ossification of sutures and fontanelles.

• Face: underdeveloped/deficient facial bones leading to prominent forehead, pseudoexophthalmos, and hypertelorism (due to small wide nasal bridge and widely spaced shallow orbits); protruding mandible.

• Dental: high arched/cleft palate, late loss of deciduous teeth with slow disordered eruption of secondary teeth (= extra/absent teeth).

• Ears: hearing loss +/– frequent ear infections.

• Upper limb: mobile drooping shoulders; completely absent/partially absent clavicle (especially lateral part, usually unilateral); recurrent dislocation shoulder/elbow; short middle and distal phalanges; long second metacarpal.

• Torso: narrow thorax and pelvis.

• Spine: delayed vertebral ossification; scoliosis/lordosis; kyphosis; prominent cervical transverse processes.

• Lower limbs: tubular phalanges of feet.

Investigations

• Skull: multiple imperfect ossification centres (wormian bones); large open anterior fontanelle; absent/delayed development of sinuses; hypoplastic maxilla.

• Clavicle: total absence/partial absence of lateral aspect clavicle (commonest) or bipartite clavicle.

• Shoulder: subluxation of humeral heads.

• Pelvis: delayed ossification pelvic bones with widened symphysis pubis; coxa vara of hips.

• Spine: failure of union of neural arches. Association with syringomelia

• Renal tract: association with Wilm’s tumour requires imaging kidneys.

Treatment

Usually abnormalities cause little functional disability. Lateral part of clav-icle may cause brachial plexus problems (if so, for excision). Recurrent dislocations of the shoulder may require stabilization. Dental anomalies should be treated by maxillofacial surgeons. Coxa vara may require valgus osteotomy.

Prognosis 

Normal lifespan.