If she will agree, sting your wife right on the L5 disc (the disc is between the vertabrae bone, not on the bone). Just try one sting and see what happens. From that, you should both be able to figure out how many and how often.
The pains in wrists and ankles are from the nerve damages in the spine I bet, I know mine are. When I get my spine all lined up and feeling better, then is when my knuckles, wrists, elbows, knees, ankles and toes flare up. Beestings help me better than all the meds and injections the doctors ever gave me. I sting myself in ankles, arches of feet, knuckles on hands, elbows, base of neck, tailbone, lumbar discs. I sting wherever it is hurting from. Disc pains can cause pain to shoot or streak. L5 will cause streaks in legs, sting the disc, not the streaks.
Best of luck, I know she's having a terrible time now. Hopefully she's not terribly allergic to beestings!
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