Otospondylomegaepiphyseal Dysplasia

Disease with peculiar facies and severe degenerative joint disease of the osteoarthritis type affecting predominantly the hips, knees, elbows, and shoulders.

Nance Insley Syndrome; Nance Sweeny Chondrodysplasia; Chondrodystrophy with Sensorineural Deafness; OSMED.

Unknown.

Autosomal recessive and dominant forms exist. The responsible gene is located on 6p21.3.

Otospondylomegaepiphyseal dysplasia (OSMED) is a type XI collagenopathy with mutations in the procollagen XI genes (COL11A1 and COL11A2). However, the exact pathomechanism remains unclear.

Based on the clinical association of peculiar facies (hypoplastic midface with short, upturned nose having depressed nasal bridge, prominent eyes, and prominent supraorbital ridges), progressive sensorineural deafness, and severe degenerative joint disease of the osteoarthritis type predominantly affecting the hips, knees, elbows, and shoulders.

Can involve head and neck (mandibular hypoplasia, Pierre-Robin sequence [micrognathia, glossoptosis, cleft palate/uvula], flattened nose and cheek bones, anteverted nares), limbs (shortening of the long bones, short fingers, and metacarpals, fusion of the carpal bones, restricted joint mobility, metaphyseal flaring, large tarsal bones, prominent interphalangeal joints), and axial skeleton (enlarged odontoid in childhood, platyspondyly, anterior vertebral wedging, coronal vertebral clefts, kyphosis, scoliosis, square iliac wings). Other features may include ventricular septal defect, recurrent lower respiratory tract infections, hemangiomas, and lacrimal duct abnormalities.

If cardiac disease is suspected, evaluate cardiac function (clinically, ECG, echocardiogram). Assess for signs of difficult airway management. If kyphosis/scoliosis is severe, obtain lung function tests and chest radiograph.

Features of the disease suggest that direct laryngoscopy and tracheal intubation may be difficult. Special precautions against corneal injury should be taken in the presence of prominent eyes and lacrimal duct abnormalities. Patient may have ventricular septal defect, which requires specific anesthesia precautions. Vascular access and patient positioning may be difficult because of joint contractures.

Avoid neuromuscular blockers and maintain spontaneous ventilation until the airway has been secured. Subacute bacterial endocarditis prophylaxis may be indicated in the presence of a cardiac lesion.

OSMED is allelic with Stickler syndrome and Weissenbacher-Zweymüller syndrome.

Stickler Syndrome: Autosomal dominant inherited disorder most often caused by mutation in the COL2A1 gene; mutations in the COL11A1 and COL11A2 are less common. The pathognomonic feature is an vitreous gel architecture, which is associated with high, congenital, and nonprogressive myopia and a significantly increased risk of rhegmatogenous (associated with retinal tears) retinal detachment. Other signs include midface hypoplasia, flat nasal bridge, short nose with anteverted nares, micrognathia, and cleft palate. Joint hypermobility usually improves with age, whereas degenerative osteoarthritic symptoms (mainly hip and knee) are progressive and become manifest in the third or fourth decade of life. Conductive (secondary to cleft palate with chronic otitis media) but predominantly sensorineural hearing loss is common. Patients are most often mentally normal and of normal height. Mitral valve prolapse syndrome (Barlow Syndrome) has been reported to be a common finding (patients may require subacute bacterial endocarditis prophylaxis ...