Heterotopic ossification in paraplegia: a possible disturbance of the paravertebral venous plexus.

The distribution of the heterotopic ossifications that complicate paraplegia and other neurological disorders is remarkably similar to that of the paravertebral venous plexus of Batson. Stasis within this system consequent to immobilization and spinal trauma, combined with demineralization of the skeleton, are postulated to be the main factors promoting precipitation of calcium salts in the soft tissues in these conditions.