it seems to me as iliotibial band syndrome as it rubs against outside of the knee joint
Tight muscles in your hips or along the side of the leg can be a major contributing factor to IT band syndrome. All of these tissues are connected, so even though the location of the pain
is in the knee, the hips can very well be the area that need the most attention.
muscles can be one of the biggest reasons people get IT band syndrome.
To strengthen the muscles most commonly affected, you can try some of the exercises suggested .
Further evaluation like walking video analysis and shoe or orthotic issues need to see and give you the best treatment. Hope this helps you. Regards.