Many different problems could cause big toe pain. If you have a hard bulge at the base of your toe, you may have a bunion. If the toe is stiff and moving it is uncomfortable, you may have arthritis. Sharp pain after an injury could be a fracture or a sprain, like turf toe. Sudden arthritis pain could be gout. Aching under the big toe at the ball of the foot could be sesamoiditis. The exact cause of your big toe pain will depend on the structures within it that are affected.