(1) Common sites of metastases include liver, bone, bone marrow, extradural space, orbits and skin.(2) The placement of extradural intracranial pressure monitors is considered safer than subdural catheters.(3) The ganglia of the fifth lumbar and first four sacral lie within the vertebral canal, but these are also extradural .(4) Extraarticular locations for tophus formation included myocardium, pericardium, aortic valves, and extradural spinal regions.(5) Despite this, overall rates of survival among older patients with extradural haematoma or subdural haematoma were not insubstantial.
