Fly-by-night marketing attempts even occur in medical field!
For the past 20 years there has been a plethora of questionable studies suggesting that possibly hyaluronic acid originally derived from rooster comb could benefit arthritic joints (sold as Synvisc, Hyalgan and Euflexxa, etc.). Careful research discloses that actually, it is a very high-cost alternative with no better response and more side-effects than cortisone injections. A number of studies have now been published mostly in Europe comparing the rooster comb chemical to PRP but suggests that PRP is slightly better. No carefully performed study has been done to compare it with corticosteroid at much lower cost. Also, there is a dearth of information to compare simple use of well-researched, inexpensive and quite safe NSAIDs with PRP. Studies previously done with NSAID vs. rooster comb extract were using subtherapeutic (less than optimal) dosages of naproxen. Compare this to shady ads on television targeting elderly people with knee arthritis offering expensive knee "braces" that are guaranteed to be paid for by Medicare! Don't be fooled.
When the fog settles, at the end of the day maintaining an ideal body weight, i.e. avoidance of obesity, exercising and, if there is no medical reason/intolerance to taking NSAID (oral more so than topical due to cost), NSAID and possible use of a cane (mandated by Medicare and Blue Cross before paying for a joint replacement) are still the best alternatives.