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 Syndrome.
Unknown. Only a few affected families reported.
Autosomal recessive and dominant forms exist.
Otospondylomegaepiphyseal dysplasia (OSMED) is a type XI collagenopathy with mutations in the procollagen XI genes (COL11A1 and COL11A2—mapped to chromosome 6p21.3). Type XI collagen is a fibril-forming collagen found mainly in the cartilage extracellular matrix and is important for the integrity and development of the skeleton. However, the exact mechanism 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.
Precautions before anesthesia
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.
No reports are available; however, 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.
Other conditions to be considered
Otospondylomegaepiphyseal dysplasia (OSMED) is allelic with Stickler Syndrome and Weissenbacher-Zweymüller Syndrome.