Hi.. The pain what your wife suffers us due to lack of stability in glute muscle resulting in loading more on hamstring muscle... Sometimes irritation in the back..facet joint or neural irritation can give rise to similar symptoms... If I were your treating doctor then I would like to be sure with certain things.... Nature of pain whether the pain is getting increased slowly of all of a sudden it started... 24 hr pattern of the pain Factors that increases the pain Factors that reduce her pain was there any investigation done before... I would like to suggest you to Do lot of icing on your back as well as over the painfully area frequently... Gently knead her painful area at the end of the day...follow that up with icing... Take frequent breaks from standing... Do regular physical exercises like walking .swimming etc.. core stability exercises like...lying on your back air cycling..golding table top position... and lying on stomach and do back extension.. glute stability exercises like Bridging...clamshell..single leg raise while lying sideways...leg kick backs..etc 15 times each..3 sets... stretching low back.. hamstrings...gluteus and calf regularly... Hope this is helpful for you... Kindly revert back incase you need further clarification.... wishing you a speedy recovery...