Although researchers have been able to establish a clear syndrome with characteristic or “core” symptoms, much about the disorder is not fully understood. Several factors including the small number of people identified with this disorder, the lack of large clinical studies, and the underlying cause of the disorder being unknown prevent physicians from developing a complete picture of associated symptoms and prognosis. Therefore, it is important to note that affected individuals may not have all the symptoms discussed below. Parents should talk to their children’s physicians and medical team about their specific case, associated symptoms and overall prognosis. The major physical characteristics of Weismann-Netter-Stuhl syndrome include Short stature and bowing of the front (anterior) of the long portions (shafts) of the shinbone (tibia) and the smaller bone of the leg below the knee (fibula). Sometimes the long bone of the thigh (femur) is bowed. Many affected individuals do not have any major functional limitations, and a diagnosis of Weismann-Netter-Stuhl syndrome may not be made until adolescence or adulthood because of the lack of serious complications associated with this disorder. Usually both legs are affected (bilateral). In extremely rare instances, only one leg is affected (unilateral).
Along with the characteristic bowing of the tibia and fibula, affected individuals may also exhibit bowing of the sides (lateral bowing) of the thigh bones (femur) and/or outward curvature of the tibia (saber shins). Benign (non-cancerous) overgrowths of cartilage called exostoses may affect the tibias. Additional bones may also be affected including the ribs and pelvis.
Affected individuals may also exhibit bowing of certain bones in the forearms (i.e., ulna and radius), malformation of a part of the hip bone (ilium), improper development of bone toward the bottom of the spinal column (horizontal sacrum), widening of the marrow cavities inside bones, and/or Thickening of the outer layers (cortexes) of the long bones (diaphyseal dysplasia). Sometimes, a hip deformity in which the thigh bone is angled toward the center of body (coxa vara) is present.
In addition, some affected individuals may exhibit a sideways curvature of the spine (scoliosis), an inward curvature of the back (lordosis) so that the back curves into the body, and/or a front-to-back curvature of the spine (kyphosis) so that the upper back is rounded. Most affected individuals begin to walk later than is normally expected, however, the reason for this delay is not understood.
There have been reports of intellectual disability in some children as well as an enlarged thyroid (goiter) and low levels of circulating red blood cells (anemia). However, some researchers believe that these findings may be coincidental and not features of Weismann-Netter-Stuhl syndrome.