Induction of systemic bone changes by preconditioning total body irradiation for bone marrow transplantation.

BACKGROUND

Preconditioning total body irradiation (TBI) prior to bone marrow transplantation (BMT) has been believed to be a safe procedure that does not cause late morbidity; yet, a recent report raises the suspicion that TBI-induced chondroosseous abnormalities do occur.

OBJECTIVE

To evaluate the radiological manifestations of TBI-induced skeletal alterations and their orthopaedic morbidity.

MATERIALS AND METHODS

Subjects included 11 children with TBI-induced skeletal changes, including 9 in our hospital and 2 in other hospitals. The former were selected from 53 children who had undergone TBI with BMT. Radiographic examinations (n=11), MRI (n=3), CT (n=2), and medical records in the 11 children were retrospectively reviewed.

RESULTS

The skeletal alterations included abnormal epiphyseal ossification and metaphyseal fraying (8/11), longitudinal metaphyseal striations (8/11), irregular metaphyseal sclerosis (6/11), osteochondromas (4/11), slipped capital femoral epiphysis (2/10), genu valgum (3/10), and platyspondyly (2/3). MRI demonstrated immature primary spongiosa in the metaphysis. Of the 11 children, 9 had clinical symptoms.

CONCLUSION

TBI can induce polyostotic and/or generalized bone changes, mainly affecting the epiphyseal/metaphyseal regions and occasionally the spine. The epi-/metaphyseal abnormalities represent impaired chondrogenesis in the epiphysis and growth plate and abnormal remodelling in the metaphysis. Generalized spine changes may lead to misdiagnosis of a skeletal dysplasia.