Hello. Thank you for coming to JustAnswer with your question, and welcome.
Psoriasis is one possibility, and the areas your husband has a problem with would be typical for this.
Good quality moisturizers may help, even if this is an eczema. He should apply the moisturizer after bathing while the skin is still warm and damp. An emollient is usually better than a lotion. And he can also apply the moisturizer at least once more during the day.
However, for effective treatment, he should see his doctor for a diagnosis. Both psoriasis and eczema will do better with prescription medications, even if topical.
Here is a link with more information from Mayo Clinic's site: Psoriasis