Surgical correction of postradiation spinal deformity.

BACKGROUND Radiation to the juxtaspinal area in children with malignant tumors induces the appearance of a postradiation spinal deformity (PRSD) with drastic progression during the growth spurt, so surgical correction is mandatory. Methods of surgical treatment depend on the age of the patient, and the type and size of the spinal deformity. METHODS A long-term retrospective survey of 6 patients receiving surgical management of kyphoscoliosis was conducted. The original tumors were 3 Wilms' tumors, 2 neuroblastomas, and 1 lymphoma. The mean length of time for tumor excision and subsequent radiation was 2.2 years. The total radiation dose averaged 3566 rad. The mean age at initial presentation was 6.1 years and that at spinal correction was 11.8 years. Single posterior surgery was performed in 3 cases, while the other 3 required anteroposterior correction due to severe deformity and scar contracture. RESULTS The curves of PRSD were concave toward the side irradiated, and the kyphotic component was more severely involved than was the scoliotic component. Four patients had favorable correction without curve progression. However, in the other 2 younger patients, due to thinness of their back, rigid angulation of the spine, poor bony stock, and medical comorbidity, spinal instrumentation was rather difficult. Postoperative pseudarthrosis and subsequent rod protrusion occurred with progressive kyphosis. CONCLUSIONS PRSDs consist of uncommon developmental vertebral anomalies, of which curved patterns occur in any combination, but most severely involve the presence of collapsing kyphosis and soft tissue contracture. Surgical correction may be less effective, especially if the children are skinny and have low bone stocks.