Sciatica and neoplasias of the spine

Like other forms of sciatica pain is caused when a neoplasia compresses the spinal roots. Patients present with typical symptoms of sciatica but may also have other symptoms including slight paralysis, spinal deformity (e.g. scoliosis, kyphosis), and fever. Sciatic pain can occur at rest, be worse at night, and may or may not be related to activity. Neoplasias need to be ruled out if sciatic pain does not resolve or if neurologic deficit is experienced (one of Murtagh’s ‘unmissables’).

There are three kinds of neoplasia that can affect the spin:
• Extradural (similar to epidural only does not have to be immediately outside the dura mater.
• Extramedullary (outside of any medulla oblongata)
• Intramedullary (within the bone or medullar oblongata)

Both extradural and extramedullary neoplasias can cause compression of the spinal cord. This generally takes weeks to months and typically present with root pain and sensory loss. Intramedullary tumours are rarer and typically progress over many years.

Neoplasias of the spine are typically secondary cancers formed by metastatic neoplasias of the bronchus, breast, prostate, lymphoid, thyroid or skin (melanomas), and so may often imply more serious implications.