have you checked the obvious things such as his collar for anything that may be sticking in him sometimes they are stitched with something that looks like cat gut or clear fishing line and as it comes un stitched it pokes outand can be quite pointy , have you checked him for fleas , have you checked him for any signs of irritation under his collar ? thats the obvious over with ! the more obscure Hmmmmmm im at a loss he could just be doing it for effect as it gets him attention try ignoring it once you,ve assertained that there are no physical reasons for this display of behaviour , and once he walks again after scratching give him a good boy and a treat , but only if he walks properly again .
Andrea

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