Osseous Manifestations of Tuberous Sclerosis Complex

Bony manifestations of tuberous sclerosis complex include both sclerotic and lucent lesions. The sclerotic lesions are most commonly found in the axial skeleton, while the lucent lesions are found most commonly in the hands and feet.

Other skeletal manifestations include hyperostosis of the inner table of the calvaria, scoliosis, and macrodactyly.

Sclerotic Bone Lesions

Sclerotic bone lesions are the third most common imaging finding in patients with tuberous sclerosis (after brain tubers and renal angiomyolipomas). Histologically, they represent areas of concentric osteosclerosis in the medullary cavity.

Sclerotic bone lesions are almost always located in the spine and commonly in the pelvis, but can also be seen in the ribs (as in the left posterior 5th rib in the case above), sternum and the axial skeleton. Involvement of the skeleton is usually extensive. The lesions are usually round or oval, but can also be flame-shaped.

Lucent Lesions

Lucent lesions are thought to represent hamartomas and are found in the phalanges of the hands and feet in 2/3 of patients. Because they are asymptomatic, they are seen incidentally on radiographs of the hands and feet obtained for other reasons.

On radiographs, they are irregularly circumscribed lucent lesions with a sclerotic appearance peripherally. A distinct wavy periosteal reaction has been described along the shafts of the metacarpals and metatarsals. While the lucent lesions are more common in the hands, the periosteal reaction tends to be more common in the feet.

References

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