Hello and hope you are doing well.
Why was the second surgery done? Normally, in cases where allergies are present, you will experience: hives ( raised red blotches, itchy or painful ) swelling of the tongue/ lips/ throat, dizziness, and other symptoms like wheezing or rhinitis. For titanium allergy, you should have reactions at the site of insertion. Also, studies are being done to see if titanium implants can affect the kidneys. Sciatica can also cause the symptoms described by you. There is back pain which radiates to the leg and foot. This can be caused due to spinal disc herniation, spinal stenosis and piriformis syndrome. You can try avoiding those postures and movements which aggravates your symptoms. Could try cold or hot compress for relief from pain. Please discuss this with your doctor am sure he will provide further assistance. Usually it is treated conservatively (without surgery).
Hope this helped and do keep us posted.