It wont be the chipping as said it goes into the fatty tisue in the scruff no deeper , our Daisy acquired a limp at about 9 months had her x rayed and it showed signs of OCD a form of cartilidge damage in the elbow joint , it can be cause through too much exercise while in the growing stage as bones are lenghtening and growing so restricting your dog to a lead for a while will give it time to settle if your worried about it getting worse or not getting better go back to the vet and have them look for anything else it could be .

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