Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain there can be a number of reasons for pain in tailbone and hips and few common causes are
Coccydynia [inflammation of tailbone], sciatica, traumatic injury,
nerve damage, Sarcoilitis, pilonidal cysts etc..
I would suggest you to consult an Orthopedician and get evaluated and as you have already got MRI scan and xrays done you can get them evaluated for the diagnosis..
You can be advised to take painkillers like
Acetaminophen or
Ibuprofen, muscle relaxants like Chloxzoxasone,
physiotherapy to relieve tensed muscles, massage with medicated pain relieving oils can help..
You should also avoid long sitting sessions, bend a little forwards while sitting, try loose weight if obese..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.