Do prp injections work on achilles tendonosis?

Sometimes: Mixed results reported in medical literature.

Not In My Experience: Prp was thought to be a revolutionary cure for most types of tendinitis. But, studies have shown it to be no more effective than just using the needle alone (dry needling). There is a treatment called topaz which works very much the same way but usually has better results. If you have a heel spur, however, usually the best invasive intervention is to have the spur removed.