My husband has found a lump on his left buttock.  It is quite hard and about the size of a golf ball and a little bit tender .  There is no visible marks just when you put your hand over it you can feel it.  He is at present being treated for sciatica on the same side.  Thanks for your help/
Hi, This lump will not be related to sciatica. The sciatic nerve lies very deep in the thigh. The lump may be a lipoma, which is a fatty lump. Or it may be a sebaceous cyst. Chat Doctor.