The incompletely fused bones of adolescence favor Osgood-Schlatter disease. Your husband can attest to the rest required for complete recovery. The condition has made many a summer miserable for young competitors. Besides sports, stair climbing, running and any activities causing pain are forbidden. If pain persists beyond two weeks of rest, then casting is done.
Complete healing takes two to four months.
I have tried various shampoos. The scales of psoriasis are remnants of skin cells that have grown in haste and shed in profusion, a matter of too-rapid cell turnover. Psoriasis can affect the scalp only, and you testify to the difficulty of treating such a scalp condition. If those remedies fail, cortisone might alter things, either in gel or shampoo form. Follow label instructions.