Hi,
Thanks for your query.
Low back ache may be due to many reasons like musculoskeletal reasons,pelvic pathology etc.
You need proper clinical examination and routine investigations.
Investigations include routine hemogram,random blood sugar,liver function test,renal function test,urine RE/ME,
ultrasound of abdomen,X-ray L/S spine (AP/Lateral view),
Thyroid profile,serum calcium and vitamin D level.
MRI of L/S spine can be done after evaluation.Pain may be due to
intervertebral disc prolapse in lumbo-scaral region.
Proper treatment depend upon findings.
You may need to take few medicines and
physiotherapy.
I do hope that you have found something helpful and I will be glad to answer any further query.
Take care