Osteoarthritis. new bone spur, nerve pain radiating from ankle - worried will overdose on pain meds

Dear Ask The Doctor: I'm writing this for my mother because she's not a complainer and would think I'm silly for writing this in. My mother (55) has had osteoarthritis pain since her 30s. She will frequently get a new bone spur (in each finger, elbows, a shoulder, a knee) which will hurt while it is forming but then become bearable. She has been on Piroxicam (20mg) for over a year which helps with her run-of-the-mill joint pain. In recent months, a new bone spur appears to be forming on her right ankle which has begun to hurt a lot (much more pain than she has ever experienced - including 4 med-free childbirths and the pain that eventually led her to get a double hip replacement.) She feels searing ankle pain and numbness with tingling pain shooting down from her ankle to her toe and up from her ankle all the way to her hip. My limited anatomy understanding makes me wonder if her ankle bone spur is pushing on the bundle of nerves on the outside of the ankle and perhaps even the ligament holding them all in. To make the pain manageable enough to load the dishwasher or walk to the bathroom, she had been taking a LOT of Tylenol. However when I did the math, I realized she was taking 12g of Tylenol in 12 hours (when the so-called lethal dose is 6-10g and the max recommended for a day is 4g) I made her take less. She's since had her liver and kidneys tested and those short-term high doses appear to have done no lasting damage. She had been taking Tylenol rather than Advil because Advil and Piroxicam are both NSAIDs, better not to mix. But now, when she reaches her safe limit of Tylenol, she tries an Advil or two a few hours later, just so she can stand the pain without crying. She went to her PC doctor who checked her liver and kidneys (good), tested her for rheumatoid arthritis (even though she doesn't have the symptoms for that and her records prove that she tested negative for it years ago), x-rayed her back (not really indicated, but fine) and her right ankle (well, she tried to x-ray her left ankle until my mom stopped them and said "isn't this supposed to be my right ankle?" - the results of which were inconclusive). She's now scheduled for an MRI of the right ankle in a week and a half. Her doctor has also prescribed her Valium so she can sleep through the pain at night and not wake up and take more pain medication every few hours. The doctor did not increase her Piroxicam, called Tylenol "useless sugar pills," and when my mother asked whether an injection of cortisone in the ankle might decrease some of the pain and swelling, the doctor gave her an injection in her hip. When my mother asked what was in the injection, the doctor responded "I'm doctor. You're patient." So of course my mother is going to be switching PC doctors, and she has an appointment with a well-regarded rheumatologist in a month (the soonest available appointment). She had moved so had to start with new doctors here. My question is really a math question about pain management until then. Luckily she is now on spring break but needs to go back to her job as a middle school principal in a week. She's been icing and applying heat with mild relief for a few minutes. While on 20mg of Piroxicam, and with the daily recommended limit of Tylenol being 4g, can she take any Advil, too, without overdosing with the Piroxicam? What would be her daily limit of Advil? Is this the maximum dose of Piroxicam? Is there anything else she can take to get through the next few weeks? Is our only option spending the day in the emergency room? She's been using her old cane from the hip replacement for weeks now, and is considering digging out the old walker too, or maybe getting a pair of crutches. But she would still be experiencing massive, distracting pain. And you have to know my mother to know that talking about joint pain, crying when it gets too bad, and sitting with her feet propped up for days at a time are SO unlike her that it is clear this is very bad pain. She is very frustrated that this is interfering with her life and hates being waited on hand-and-foot. What can she do to ease this pain for the next few weeks before her rheumatologist appointment while she still has to be back at work? Thank you.

Dear Rebecca: I can understand the frustration and the pain your mother may be experiencing. It is definately good that you are scheduled to get checked up by a rheumatologist. You are right when you say that there seems to be some involvement of the nerve bundle which is leading to such immense pain . I would advice her to keep taking piroxicam and alternate advil with tyenol since advil has a longer duration of action ie 6 hours in comparison to 4 hrs which is provided by tylenol( do not take more than 3-4 per day). In this manner she will be able to cut back on the tylenol too and not overdose. In the mean time I also encourage her to use the walker/crutches temporarily as this may help put stress off that ankle with is involved. You will need further xrays as well as investigation into her symptoms. I hope this helps.