Weismann-Netter-Stuhl Syndrome

At a glance

It is a medical condition characterized by osseous dysplasia causing variable size dwarfism, bowed legs, saber shins, mental retardation, short stature, and dural calcification. Other osseous dysplasia may include the ribs, pelvis, spinal column, and/or bones in the arms.

Synonyms

Anterior Bowing of the Legs with Dwarfism Syndrome; Toxopachyosteose Diaphysaire Tibio-Peroniere (French); Weismann-Netter Syndrome; Skeletal Dysplasia Weismann Netter Stuhl Type Syndrome.

History

This disorder was first observed in 1954 in seven patients. Its eponym comes from the names of two French doctors R. Weismann-Netter and L. Stuhl. It was initially mistakenly diagnosed as congenital syphilis, rickets, and in some cases Paget’s disease (see below). This remains the primary considerations in the differential diagnosis of this syndrome until today.

Incidence

The exact incidence remains unknown. Since its initial description in 1954, 82 cases have been reported, including only 14 pediatric patients. It affects males and females in equal numbers. However, it is suspected that, due to its rarity, it is often under-diagnosed, making it difficult to determine the true frequency in the general population.

Genetic inheritance

Presumed inherited as an autosomal dominant trait or X-linked. Most cases appear to have been sporadic and the relatively small number of familial cases suggests incomplete penetrance.

Pathophysiology

The pathogenesis is unknown. Assumed to be a primary metabolic abnormality of bone development.

Diagnosis

Clinical features consistent with the syndrome. Radiological examination is characteristic (anterior bowing of tibiae and fibulae, with cortical hyperostosis on the concave side of the curvature, slight bowing of the radius, ulna and humerus). Inconsistent radiological findings include squaring of the iliac wings, low position of the fifth lumbar vertebra in relation to the ilia, horizontal sacrum, kyphoscoliosis, and dural calcification. Alkaline phosphatase is normal or raised; bone biopsy is normal.

Clinical aspects

Short stature is the most constant manifestation (males averaging 151 cm [59.4 inches] and females 142 cm [56 inches]). The final height of the individuals affected varies significantly according to the bone involvement. Features include anterior bowing of tibiae (saber shins) and lateral bowing of femora (usually bilateral), occasional mild bowing of ulna, radius, and humerus, and delayed ambulation in childhood. Of those affected, 20% have mental retardation of variable severity. Kyphoscoliosis is present in approximately 30% of cases. Age at diagnosis has ranged from 2 weeks to 94 years. The skeletal deformities do not seem to progress during adult life. Individuals affected have a normal life expectancy.

Precautions before anesthesia

Detailed clinical history and physical examination must be performed to determine the progression of the syndrome and assess the presence of unrelated medical conditions. ...