Hi, I'm trying to buy shin guards for my girlfriend. She is aprox. 5'6. All the shin guards I've seen on the net come in limited sizes such as Child size (tried them and way too small) Adult size (too big) Some guards come in medium and large but she's tried on two pair of mediums and they were big as well. Can some one here that's around that height point me to some shin guards that should work for her? Thanks!