<s>[INST] I have a place on my lower right back, over the pelvic bone to the right of my spine about 2 inches over and an inch wide that has a small tight lump in it and a bruise that never seems to go away, at times the right side will get very swollen and painful and can cause a decrease in movement [/INST] Hi. Thanks for your query. The lumps here can most probably be a sebaceous cyst. As per your history, the tight lump and a bruise never goes away and get swollen sometimes. This excludes Not present) lipoma or muscular one. The best way to get this diagnosed is to consult a Surgeon, get a clinical diagnosis and get operated. Ultrasonography is done only if your Surgeon this that it will help. This will help in 2 ways> you get disease -free, and you get a definite diagnosis. </s>