Steroidal joint injections are illegal, Hylarounic Acid (aka Legend) joint injections are not.
So Honaysuga, you are suggesting that instead of having my 50 year old mother (who has been riding for about 5 years (10 years on and off)) on a quiet schoolmaster who is a little arthritic, I should put her on a young, inexperienced horse with no lameness issues??
What you are failing to see is that it is nearly impossible to keep a dressage horse sound. Let alone an older one with many years under it's belt that is capable of packing around a Junior or AA rider.
Most dressage people that I know have their horses who are in a full time training schedule, regardless of age, on monthly IM/IV injections and have semi annually or quarterly vet checks. They are very concerned about their horse's soundness, as they should be! Like upnover says, bute is not used to cover up lameness!!
My mother's horse is not lame at home, but the stress of trailering and standing in a stall and showing is simply too much for his arthritis to handle. Yes it is selfish to a degree but the horse is not hobbling around on 3 legs, and once he is home and has a day to recover in the field he is back to 100%. The horse has to earn his grain somehow.
Honeysuga, I strongly suggest you go read some studies about arthritis, showing and using anti-inflammatories. What you are saying is the same as suggesting that an older, mildly arthritic person who has trained for a marathon should not be allowed to compete after taking an anti-inflammatory.