welcome you to healthcare magic forum,
do you have any history of fall ,any other complaints like
stiffness and difficulty in movement early in the morning,family history of back pain?there are some causes of back pain in this age group.it may be simply
musculoskeletal pain from muscle spasm, inflammtory
arthritis or any problem in vertebral colomn.you better do some investigation like x ray of S-I joints,x ray D/l spine and a
complete blood count.it will dictate nature of your back pain.