They identified themselves as from "Pain Relief" - said that I might qualify for a topical pain creme. Since I had recent knee problems, I thought that it was legit. They asked questions to see if I was part of medicare, medicaid or had private insurance. Asked for a BIN# off my insurance card then told me that I didn't qualify. Sounds suspicious.... and you are right, the number is probably spoofed as it is listed as a fax line for a Pain Relief Clinic in TX.
To Cheri and Smith: yes can find a Pain Relief Center of TX is located at Matagorda (county) Reg(ional) M(edical) Center in Bay City, TX. And yes, 9792452079 is listed as Pain Relief Center's fax number when you go to their website.
Problem is, phone company registers this number as a landline for an individual (won't list their name since number appears to be spoofed). Granted this person resides (or resided) in Bay City. One theory is that the number is a very recent disconnect so the phone company websites have not updated their listing. This gives one pause to think that a phone company employee or contractor who has access to recently disconnected numbers will sell/trade/whatever those numbers to bad guys.
It is interesting that you mention that they are cold calling you for a topical pain medication. In the latest AARP Bulletin, south Texas is considered a huge hotspot for Medicare fraud involving--yes, you guessed it, topical pain cream. Also other arthritis relief "kits" and such. Reportedly investigators are recovering billions in dollars from these sorts of Medicare scams.
As a quick review, Centers for Medicare and Medicaid Services do not allow legitimate doctors to cold call asking for your Medicare number. AND no state allows legitimate medical professionals to cold call about remedies of any kind be it for pain, common cold or breast cancer. You bet they are suspicious and your first action should have been hang up right after they identified who they were and what they were trying to scam you with.