thanks for choosing health care magic.Joint pains
is young age are now increasing due to various issues like faulty life style,diet and lack of exercise.As per you your brother is fully investigated.You had mention about scan and x-ray,i hope blood investigation are also done.See in his age pain usually occur due to nutritional deficiency
and unusual and hurting physical activity.Give calcium rich diet like milk and milk products,banana and other fruits and food.If he is overweight
see that he does efforts to loose weight.Ask him to do exercise regularly,when in severe pain
no exercise.You can even see a physiotherapist who will guide him what exercise to be done.For immediate relief of pain you can ask your doctor for a medication.