Narrowing of the spine...Degenerative Myelopathy

I have a German Shepard/Lab mix that is 15 yrs old.  She is in good health other than the fact she has Degenerative Myelopathy.  He brother past away last year from this and she is starting to show signs of having it also.  I heard about Sanus-Biotex and it is supposed to really help dogs with this problems.  I have been reading alot and I want to know if anyone has really had good results from using this.  It is hard to tell if what I am reading on the internet is just someone pushing to sell it.  So if you could please help us, well we and Ginger (our four legged baby) would really appreciate it.  She is a part of our family and it is just heartbreaking to see her having problems.  Thank you in advance for any help!