<s>[INST] I have severe mid lower back pain that is worse when standing 8/10 and 2/10 when sitting . I did have prostate cancer and received radiation and implantable seeds for treatment in 2015. I also had bilateral hip replacements in 2014,for severe arthritis.Any thoughts? [/INST] Hi I am Chat Doctor. .  In my opinion that might be sciatica due to nerve compression which is common for post-operative hip replacement patients. You may begin with relaxation, Advil tab when needed, hot massages with topical gels, some cases may need steroid injections, physiotherapy will be effective. Please consider a 5-star rating with some positive feedback if the information was helpful. Wish you good health, Any further clarifications feel free to ask. </s>