Hello, Welcome and thank you for posting to HCM, From your description and the purple coloration beneath your big toe represents a zone of hypoxia whereby there is little or no blood/oxygen circulating in that area. It might be as a result of vascular obstruction due to vascular obstruction. The obstruction might be due to vasculitis or thrombophlebitis or vascular constriction due to mass effect ( intraluminal tumor or extraluminal tumor). Since this condition has been for several years, I will be in support of a mass effect which lead to the vascular obstruction hence little blood or oxygen circulation beneath your big toe nail. This would also result into pain as surrounding nerves will also be compressed and hence neuralgic pains. I will suggest you take antiinflammatory which has thrombolytic properties like aspirin for a couple of days to weeks ( but not too high doses or for long term so as to minimize side effects strongly associated with aspirin). You will need your toe examined by a doctor and an MRI done so as to determine the actual cause for proper treatment. Surgical intervention might be needed in order to release the pressure involved and also for possible definitive treatment. Hope this helps