During Thorin's fight with the pale orc, Thorin wears his oak-limb shield on his left hand. This is typical. After Thorin falls, he is seen reaching for his sword with his right hand, consistent with his shield being on his left. However, when the eagles come & one grabs Thorin, his shield is suddenly seen on his right arm. As he's lifted off the ground, his left arm is pinned under the eagle's foot. But his right arm flops limply & his shield is seen falling off his right arm.