Of these two cases of solitary localized bone lesions, which were either congenital or occurred in early postnatal life, one was a case of localized osteitis fibrosa of the proximal third of the tibia and the other was a typical congenital pseudarthrosis in the lower third of the tibia. Both cases resulted in fracture and non-union.

Four similar cases have been reported in the literature. Three of these were described as cystic lesions. In the fourth case, there was no operative interference to demonstrate the presence or absence of cyst formation, and no fracture occurred.

In Case 1, bowing of the tibia was noted, suggesting that this lesion may have stimulated longitudinal growth from the proximal tibial epiphysis so that the tibia became relatively longer than the fibula and bowed, due to lack of support on the lateral side where the defect in the bone was most extensive.

Union was obtained, followed by normal function, through the use of full-thickness tibial bone grafts.

Each of these cases adds support to the contention of Stierlin, von Beust, and Frangenheim that fibrous or cystic disease of the bone is the underlying cause of congenital pseudarthrosis.