Unless she's had orthopedic surgery before, you can't assume this. I never have pain killers in my home because my pain tolerance is really fairly remarkable, yet a joint replacement in my toe with a bunionectomy had me in such intense pain for three days that even morphine couldn't kick it. The key, IMO, is to discuss sensible pain management with the doctor before, and stick to the regimine. Once you get breakthrough pain in the first few days, the only way to likely manage it is through injected drugs like Demerol or Keterolac. This would mean returning to the clinic for pain management. It isn't unreasonable to ask for something like Oxycodone, but many providers are loathe to prescribe it.I will give this for my mom--she has a HIGH pain tolerance and will push through a lot, so I might be overly optimistic but I think she'll be OK.
Not trying to be an alarmist, but there is no need to suffer days of intense pain. Please do your Mother a favor and discuss with the doctor beforehand if he will be willing to prescribe stronger meds for at least the first week.