Spina bifida and unilateral focal destruction of the distal femoral epiphysis.

Focal destruction of the postero-lateral distal femoral epiphysis was present on radiographs in two children with spina bifida and objective lower limb sensory loss. Each patient presented with painless swelling of the knee. In one patient the epiphysis showed sclerosis and fragmentation associated with a defect. In the second patient the destructive change was the dominant radiographic abnormality and simulated bone tumor. Computed tomography in this patient showed a bone fragment occupying the defect suggesting epiphyseal fracture. The lesion in each patient was believed to be traumatic in origin and to represent a stage in the development toward neuropathic arthropathy.